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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2000 on: November 17, 2017, 10:51:27 PM »
The following is a short list of conceptual Catch 22's, associated with climate change, that may keep society on a pathway to socioeconomic collapse by 2050 (which will make it difficult to stay on any given assumed SSP pathway thru the end of this century):

1. For developing countries: Developing nations need to strengthen their economies to mitigate the issues facing their populations, issues that will be exacerbated by climate change. However strengthening their economies requires energy. Energy production currently causes greenhouse gas, which causes climate change.

2.  For consensus climate science:  Consensus climate science needs to be taken seriously by both the public and by decision makers; therefore they tend to err on the side of least drama.  Consequently, both the public and decision makers underestimate climate risks and tend to focus on other right-tailed risks such as those posed by terrorists, recessions, immigration, etc.  This results in the increase of climate risks with each passing month.

3. For military organizations: Military organizations facilitate the BAU fossil-fuel driven global economy that has set global population to have a 50-50 chance or reaching 9.8 billion by 2050.  However, the current socioeconomic landscape is generating increased tensions that result in epicenters of potential violence (stressed by climate change) that will require military organizations to increasing deal with such issues as food shortages (see the first image), water shortages (see the last three image) and nationalism/regionalism.

Title: "Epicenters of Climate and Security"

https://climateandsecurity.org/epicenters/

Extract: "… security experts identify 12 key climatic risks to international security that may shape the geostrategic landscape of the 21st century. In the wake of extraordinary upheaval in the international effort to address climate change, the report presents a compelling case for why tackling these climate and security “epicenters” – major categories of climate-driven risks to international security – should be a top priority for governments and institutions around the world. The report also outlines the key tools for managing systemic risks that should be included in every climate security practitioner’s and policy-maker’s toolbox."
« Last Edit: November 17, 2017, 11:12:44 PM by AbruptSLR »
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2001 on: November 19, 2017, 12:28:16 AM »
I have previously recommended that AR6 try to rank the accuracy (or bias) of the different climate models that it is referencing and weigh AR6's reliance on those projections based on such a ranking.  The linked references indicate that for the first time in the CMIP program, CMIP6 will at least try to account for this consideration:

Pincus, R., Forster, P. M., and Stevens, B.: The Radiative Forcing Model Intercomparison Project (RFMIP): experimental protocol for CMIP6, Geosci. Model Dev., 9, 3447-3460, https://doi.org/10.5194/gmd-9-3447-2016, 2016.

https://www.geosci-model-dev.net/9/3447/2016/

Abstract. The phrasing of the first of three questions motivating CMIP6 – “How does the Earth system respond to forcing?” – suggests that forcing is always well-known, yet the radiative forcing to which this question refers has historically been uncertain in coordinated experiments even as understanding of how best to infer radiative forcing has evolved. The Radiative Forcing Model Intercomparison Project (RFMIP) endorsed by CMIP6 seeks to provide a foundation for answering the question through three related activities: (i) accurate characterization of the effective radiative forcing relative to a near-preindustrial baseline and careful diagnosis of the components of this forcing; (ii) assessment of the absolute accuracy of clear-sky radiative transfer parameterizations against reference models on the global scales relevant for climate modeling; and (iii) identification of robust model responses to tightly specified aerosol radiative forcing from 1850 to present.

Complete characterization of effective radiative forcing can be accomplished with 180 years (Tier 1) of atmosphere-only simulation using a sea-surface temperature and sea ice concentration climatology derived from the host model's preindustrial control simulation. Assessment of parameterization error requires trivial amounts of computation but the development of small amounts of infrastructure: new, spectrally detailed diagnostic output requested as two snapshots at present-day and preindustrial conditions, and results from the model's radiation code applied to specified atmospheric conditions. The search for robust responses to aerosol changes relies on the CMIP6 specification of anthropogenic aerosol properties; models using this specification can contribute to RFMIP with no additional simulation, while those using a full aerosol model are requested to perform at least one and up to four 165-year coupled ocean–atmosphere simulations at Tier 1.


See also

Piers M. Forster et al. (27 October 2016), "Recommendations for diagnosing effective radiative forcing from climate models for CMIP6", JGR Atmospheres, DOI: 10.1002/2016JD025320 

http://onlinelibrary.wiley.com/doi/10.1002/2016JD025320/abstract

Abstract: "The usefulness of previous Coupled Model Intercomparison Project (CMIP) exercises has been hampered by a lack of radiative forcing information. This has made it difficult to understand reasons for differences between model responses. Effective radiative forcing (ERF) is easier to diagnose than traditional radiative forcing in global climate models (GCMs) and is more representative of the eventual temperature response. Here we examine the different methods of computing ERF in two GCMs. We find that ERF computed from a fixed sea surface temperature (SST) method (ERF_fSST) has much more certainty than regression based methods. Thirty year integrations are sufficient to reduce the 5–95% confidence interval in global ERF_fSST to 0.1 W m−2. For 2xCO2 ERF, 30 year integrations are needed to ensure that the signal is larger than the local confidence interval over more than 90% of the globe. Within the ERF_fSST method there are various options for prescribing SSTs and sea ice. We explore these and find that ERF is only weakly dependent on the methodological choices. Prescribing the monthly averaged seasonally varying model's preindustrial climatology is recommended for its smaller random error and easier implementation. As part of CMIP6, the Radiative Forcing Model Intercomparison Project (RFMIP) asks models to conduct 30 year ERF_fSST experiments using the model's own preindustrial climatology of SST and sea ice. The Aerosol and Chemistry Model Intercomparison Project (AerChemMIP) will also mainly use this approach. We propose this as a standard method for diagnosing ERF and recommend that it be used across the climate modeling community to aid future comparisons."
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2002 on: November 19, 2017, 06:37:41 AM »
If U.S. CLIVAR (see Reply #1997) gets a funding extension, maybe they could help to develop a better understanding of the glacial methane cycle; which is still not adequately understood:

Hopcroft et al. (2017), "Understanding the glacial methane cycle", Nature Communications 8, Article No. 14383, doi: 10.1038/ncomms14383

http://www.nature.com/articles/ncomms14383?WT.feed_name=subjects_climate-sciences

Abstract: "Atmospheric methane (CH4) varied with climate during the Quaternary, rising from a concentration of 375 p.p.b.v. during the last glacial maximum (LCM) 21,000 years ago, to 680 p.p.b.v. at the beginning of the industrial revolution.  However, the cause of this increase remain unclear; proposed hypotheses rely on fluctuations in either the magnitude of CH4 sources of CH4 atmospheric lifetime, or both.  Here we use an Earth System model to provide a comprehensive assessment of these competing hypotheses, including estimates of uncertainty. We show that in this model, the global LGM CH4 source was reduced by 28-46%, and the lifetime increased by 2-8%, with a best-estimate LGM concentration requires a 463-480 p.p.b.v. Simulating the observed LGM concentration requires a 46-49% reduction in sources, indicating that we cannot reconcile the observed amplitude.  This highlights the need for better understanding of the effects of low CO₂ and cooler climate on wetlands and other natural CH4 sources."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2003 on: November 19, 2017, 04:49:50 PM »
The linked reference implies that if global warming leads to an increase in SSTA in the subtropical Pacific then we will likely experience more frequent super El Nino events and more frequent hindered/suppressed La Nina events.  If so this would mean that the ECS this century would likely be significantly higher than AR5 indicates:

Jingzhi Su et al. (November 2017), "Sea surface temperature in the subtropical Pacific boosted the 2015 El Niño and hindered the 2016 La Niña", Journal of Climate, https://doi.org/10.1175/JCLI-D-17-0379.1

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-17-0379.1?utm_content=buffer801ff&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Abstract: "After the quick decaying of the 2015 super El Niño, the predicted La Niña unexpectedly failed to materialize to the anticipated standard in 2016. The diagnosis analyses, as well as numerical experiments, showed that such ENSO evolution of the 2015 super El Niño and the hindered 2016 La Niña may be essentially contributed by the sea surface temperature anomalies (SSTAs) in the subtropical Pacific. The self-sustaining SSTAs in the subtropical Pacific tend to weaken the trade winds during boreal spring-summer, leading to anomalous westerlies along the equatorial region over a period of more than one season. Such long-lasting wind anomalies provide an essential requirement for the ENSO formation, particularly before a positive Bjerkness feedback is thoroughly built up between the oceanic and atmospheric states. Besides the 2015 super El Niño and the hindered La Niña in 2016, there were several other El Niño/La Niña events that cannot be explained only by the oceanic heat content in the equatorial Pacific. However, the puzzles related with those eccentric El Niño/La Niña events can be well explained by suitable SSTAs in the subtropical Pacific. Thus, the leading SSTAs in the subtropical Pacific can be treated as an independent indicator for ENSO prediction, on the basis of the oceanic heat content inherent in the equatorial region. Because ENSO events have become more uncertain under the background of global warming and the Pacific Decadal Oscillation during recent decades, thorough investigations of the role of the subtropical Pacific in ENSO formation are urgently needed."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2004 on: November 19, 2017, 11:23:45 PM »
bligh8 cited the first reference in the "Hansen et al paper: 3+ meters SLR by 2100" thread; however, I cite it in this thread as I believe that it provides a great example of how, in my opinion, AR6 should present the significance of the 'deep uncertainty' of the potential impacts of the many dynamical Earth Systems that AR6 is almost certain to be overconfident about.  The Bakker et al (2017) reference presents a worked example of how to calibrate a scenario (see the first image for part of the calibration process using both paleo ,and observed, data) for the potential collapse of the WAIS this century.  Bakker et al (2017) then effectively summarize the findings from their calibrated scenario, w.r.t. to its impact on SLR, in an easily understood plot (see the second attached image) of Sea level with time and scenarios with varying degrees of 'deep uncertainty.  Also, I note that Bakker et al (2017) indicate that: "Around 2040-2050, a large and uncertain contribution of the GIS becomes important …"

Alexander M. R. Bakker, Tony E. Wong, Kelsey L. Ruckert & Klaus Keller (2017), "Sea-level projections representing the deeply uncertain contribution of the West Antarctic ice sheet", Scientific Reports 7, Article number: 3880; doi:10.1038/s41598-017-43134-5

http://www.nature.com/articles/s41598-017-04134-5

Abstract: "There is a growing awareness that uncertainties surrounding future sea-level projections may be much larger than typically perceived. Recently published projections appear widely divergent and highly sensitive to non-trivial model choices. Moreover, the West Antarctic ice sheet (WAIS) may be much less stable than previous believed, enabling a rapid disintegration. Here, we present a set of probabilistic sea-level projections that approximates the deeply uncertain WAIS contributions. The projections aim to inform robust decisions by clarifying the sensitivity to non-trivial or controversial assumptions. We show that the deeply uncertain WAIS contribution can dominate other uncertainties within decades. These deep uncertainties call for the development of robust adaptive strategies. These decision-making needs, in turn, require mission-oriented basic science, for example about potential signposts and the maximum rate of WAIS-induced sea-level changes."

Extract: "Our sea-level projections are constructed to support robust decision frameworks by i) being explicit about the relevant uncertainties, both shallow and deep; ii) communicating plausible ranges of sea-level rise, including the deep uncertainties surrounding future climate forcings and potential WAIS collapse; and iii) tending to err on the side of underconfident versus overconfident when possible.

Model design. We design the projections to be probabilistic where reasonable and explicit about deep uncertainties (e.g. resulting from non-trivial model choices) when needed. Robust decision frameworks often apply plausible rather than probabilistic ranges to represent and communicate uncertainties. In the case of sea-level projections, the bounding of the plausible range usually involves both a probabilistic interpretation of the surrounding uncertainties and estimates of which probabilities are still relevant. For example, a full disintegration of the major ice sheets is often not taken into account because the probabilities of this occurring are considered too
small to be relevant. What probability is relevant is highly dependent on the decision context and therefore it makes sense to be explicit about the probabilities. Moreover, probabilities are the easiest and most unambiguous way to communicate uncertainties.

Our projections are designed to highlight the relatively large deep uncertainties, notably those resulting from future climate forcings and those surrounding potential WAIS collapse (even though representations of deep uncertainty often implicitly encompass probabilistic interpretations). The future climate forcing is, to a large extent, controlled by future human decisions.

The probability of a WAIS collapse is potentially much larger than previously thought due to the combined effects of Marine Ice Sheet Instability (MISI), ice cliff failure and hydrofracturing. The discovery of this new mechanism puts earlier expert elicitations in a different light as it is unclear if those were based on this combined effect. One approach when faced with deeply uncertain model structures and priors is to present a potential WAIS collapse as deeply uncertain by means of a plausible range. We stress that this range is not meant to represent an implicit probabilistic projection of the WAIS contribution to sea-level rise.

We merge some small deep uncertainties into the probabilistic part of the projections. According to Herman et al. “… a larger risk lies in sampling too narrow a range (thus ignoring potentially important vulnerabilities) rather than too wide a range which, at worst, will sample extreme states of the world in which all alternatives fail”.  Thus, in the context of informing robust decision making, it can be preferable to be slightly under- than slightly overconfident. To minimize the risk of producing overconfident projections we only use observational data with relatively uncontroversial and well-defined error structure.

Model setup. We use a relatively simple (39 free physical and statistical parameters), but a mechanistically motivated model framework to link transient sea-level rise to radiative concentration pathways applying sub-models for the global climate, thermal expansion (TE), and contributions of the Antarctic ice sheet (AIS), Greenland ice sheet (GIS) and glaciers and small ice caps (GSIC) (see Methods). This approach extends on the semi-empirical model setup recently reported by Mengel et al..

We use a Bayesian calibration method, wherein paleoclimatic data is assimilated with the AIS model separately from the calibration for the rest of the model, which assimilates only modern observations. Modern model simulations are then run at parameters drawn from the two resulting calibrated parameter sets (AIS and rest-of-model) and compared to global mean sea-level (GMSL) data (see Methods). Only model realizations which agree with each GMSL data point to within 4σ are admitted into the final ensemble for analysis. 4σ was chosen so the spread in the model ensemble characterizes well the uncertainty in the GMSL data (Fig. 1f). We choose, at this time, not to use paleo-reconstructions nor reanalyses, beyond incorporating a windowing
approach into our calibration method for the Antarctic ice-sheet parameters. This choice is motivated by the highly complex and uncertain error structure of these data sets. Failure to account for such complex error structure can result in considerable overconfidence, especially for low-probability events."

Furthermore, Bakker et al (2017) cite the second linked reference which provides a worked example of how the potential bias of a current model can be quantified by comparing its projections against the projections of a dynamical model with 'deep uncertainty', in this cases one that includes the dynamical mechanism of cliff failures and hydrofracturing w.r.t. to SLR contributions from the Antarctic ice sheet.  To the best of my understanding none of the Earth System Models in CMIP6 include the dynamical cliff failures, and hydrofracturing, mechanisms, apparently due to 'deep uncertainty'.  Nevertheless, even if CMIP6/AR6 do not present projections including the impacts of the dynamical cliff failures, and hydrofractuing, mechanisms, they could still numerically present the potential bias of their projections by following the methodology presented by Ruckert et al (2017), & in this regards see the last two attached images.


Kelsey L. Ruckert, Gary Shaffer, David Pollard, Yawen Guan, Tony E. Wong, Chris E. Forest &Klaus Keller (2017), "Assessing the impact of retreat mechanisms in a simple Antarctic ice sheet model using Bayesian Calibration", PLoS ONE, 12, 1-15, https://doi.org/10.1371/journal.pone.0170052

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0170052

Abstract: "The response of the Antarctic ice sheet (AIS) to changing climate forcings is an important driver of sea-level changes. Anthropogenic climate change may drive a sizeable AIS tipping point response with subsequent increases in coastal flooding risks. Many studies analyzing flood risks use simple models to project the future responses of AIS and its sea-level contributions. These analyses have provided important new insights, but they are often silent on the effects of potentially important processes such as Marine Ice Sheet Instability (MISI) or Marine Ice Cliff Instability (MICI). These approximations can be well justified and result in more parsimonious and transparent model structures. This raises the question of how this approximation impacts hindcasts and projections. Here, we calibrate a previously published and relatively simple AIS model, which neglects the effects of MICI and regional characteristics, using a combination of observational constraints and a Bayesian inversion method. Specifically, we approximate the effects of missing MICI by comparing our results to those from expert assessments with more realistic models and quantify the bias during the last interglacial when MICI may have been triggered. Our results suggest that the model can approximate the process of MISI and reproduce the projected median melt from some previous expert assessments in the year 2100. Yet, our mean hindcast is roughly 3/4 of the observed data during the last interglacial period and our mean projection is roughly 1/6 and 1/10 of the mean from a model accounting for MICI in the year 2100. These results suggest that missing MICI and/or regional characteristics can lead to a low-bias during warming period AIS melting and hence a potential low-bias in projected sea levels and flood risks."

Extract: " We calibrate a simple AIS model (that does not include a cliff instability mechanism nor is able to capture regional characteristics) with observational constraints over the past 240,000 years using a Bayesian inversion considering the heteroskedastic nature of the data. Using the hindcasts and projections, we compare our results to those from a pre-calibration method and expert assessments with potentially more realistic models. We approximate how neglecting fast processes (i.e., the MICI mechanism) in an AIS model can lead to biases in the AIS hindcasts and projections during warming periods. For the specific example considered, we show how missing MICI produces a lower mean hindcast (roughly 26% or 1 m smaller) during the LIG, a period when the marine ice sheet is suggested to have deglaciated. Additionally, the model is unable to account for roughly 96 and 100% of future AIS contributions predicted by a physically more realistic model accounting for MISI, MICI, and hydro-fracturing yet reproduces the projected median melt in other expert assessments in the year 2100. Overall, accounting for retreat mechanisms can potentially increase warming period AIS melt and reduce model discrepancy."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2005 on: November 19, 2017, 11:55:40 PM »
As a follow-on to my last post, I note that it seems like consensus climate science , as represented by the SSP families of radiative forcings, RFs, scenarios, is biased when virtually all of the SSP scenarios considered fall below SSP5 baseline, which is the pathway that we are currently following.  In this regards, I reiterate that numerous references cited in this thread present finding that consideration of various (/numerous) dynamical feedback mechanisms result in effective radiative forcings, ERFs, that are significantly higher than for the RFs included in the SSPs.

Therefore, in order to better quantify the potential impacts of the 'deep uncertainties' associated with such dynamical feedback mechanism as ice-climate feedback, bipolar feedback (with hosing from both the AIS and the GIS as cited by Bakker et al (2017)), methane cycles, etc.; I recommend that once CMIP6 is complete that the projections from their various models that the potential impacts of the 'deep uncertainties' associate with each of these dynamical feedback mechanisms be determined using parallel methodologies to that used in Bakker et al (2017), and be reported in AR6 for each of the SSP scenarios, this century.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Neven

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Re: Conservative Scientists & its Consequences
« Reply #2006 on: November 20, 2017, 09:18:30 AM »
Quote
James Hansen, Pam Peterson, and Philip Duffy join us to discuss how the hesitancy among scientists to express the gravity of our situation is a major block to our understanding and response to climate change, The reticence results from a combination of factors: political pressure, institutional conservatism, the desire to avoid controversy, aspiring to objectivity, etc.  But when the data and the conclusions it leads to are alarming, isn't it imperative that the alarm be transmitted publicly? Here is another facet of society's apparent inability to assess and respond appropriately to the present immense, existential threat of climate change.

https://www.youtube.com/watch?v=S7z61UZoppM&feature=youtu.be
Compare, compare, compare

AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2007 on: November 20, 2017, 08:18:57 PM »
Quote
James Hansen, Pam Peterson, and Philip Duffy join us to discuss how the hesitancy among scientists to express the gravity of our situation is a major block to our understanding and response to climate change, The reticence results from a combination of factors: political pressure, institutional conservatism, the desire to avoid controversy, aspiring to objectivity, etc.  But when the data and the conclusions it leads to are alarming, isn't it imperative that the alarm be transmitted publicly? Here is another facet of society's apparent inability to assess and respond appropriately to the present immense, existential threat of climate change.

Hansen is correct when he indicates that climate scientists have already provided more than enough evidence for world leaders to implement aggressive carbon fee programs, and yet almost no such programs have been implemented, thus indicating that most of the responsibility for our current risky situation fall on the shoulders of the decision makers.  Nevertheless, I believe that the message conveyed by this COP23 video significantly underplays our actual risks.  And as just one example of why I believe that our risk of passing one, or more, tipping points in the next few decades is very real, I note that current ESM projections (including Hansen's) cannot replicate the ECS observed during the MIS 11 interglacial period about 400 kya, and in this regard I provide the two following linked references on MIS 11 response and I recommend that the IPCC highlight the risk associated with such 'deep uncertainties':

Kandiano et al. (2017), "Response of the North Atlantic surface and intermediate ocean structure to climate warming of MIS 11" Scientific Reports 7, Article No. 46192, doi:10.1038/srep46192

http://www.nature.com/articles/srep46192

Extract: "Our results underscore the intricate interdynamic behavior of the North Atlantic climate system.  Furthermore, if the present-day rapid summer melting of the GIS continues, the resulting freshening of the surface ocean may well lead to fundamental structural changes in both ocean and atmospheric circulation as reconstructed for MIS 11."

&

Coletti, A. J., DeConto, R. M., Brigham-Grette, J., and Melles, M.: A GCM comparison of Pleistocene super-interglacial periods in relation to Lake El'gygytgyn, NE Arctic Russia, Clim. Past, 11, 979-989, doi:10.5194/cp-11-979-2015, 2015.

http://www.clim-past.net/11/979/2015/cp-11-979-2015.pdf
http://www.clim-past.net/11/979/2015/cp-11-979-2015.html

Abstract: "Until now, the lack of time-continuous, terrestrial paleoenvironmental data from the Pleistocene Arctic has made model simulations of past interglacials difficult to assess. Here, we compare climate simulations of four warm interglacials at Marine Isotope Stages (MISs) 1 (9 ka), 5e (127 ka), 11c (409 ka) and 31 (1072 ka) with new proxy climate data recovered from Lake El'gygytgyn, NE Russia. Climate reconstructions of the mean temperature of the warmest month (MTWM) indicate conditions up to 0.4, 2.1, 0.5 and 3.1 °C warmer than today during MIS 1, 5e, 11c and 31, respectively. While the climate model captures much of the observed warming during each interglacial, largely in response to boreal summer (JJA) orbital forcing, the extraordinary warmth of MIS 11c compared to the other interglacials in the Lake El'gygytgyn temperature proxy reconstructions remains difficult to explain. To deconvolve the contribution of multiple influences on interglacial warming at Lake El'gygytgyn, we isolated the influence of vegetation, sea ice and circum-Arctic land ice feedbacks on the modeled climate of the Beringian interior. Simulations accounting for climate–vegetation–land-surface feedbacks during all four interglacials show expanding boreal forest cover with increasing summer insolation intensity. A deglaciated Greenland is shown to have a minimal effect on northeast Asian temperature during the warmth of stages 11c and 31 (Melles et al., 2012). A prescribed enhancement of oceanic heat transport into the Arctic Ocean does have some effect on Lake El'gygytgyn's regional climate, but the exceptional warmth of MIS 11c remains enigmatic compared to the modest orbital and greenhouse gas forcing during that interglacial."

Extract: "The timing of significant warming in the circum-Arctic can be linked to major deglaciation events in Antarctica, demonstrating possible interhemispheric linkages between the Arctic and Antarctic climate on glacial–interglacial timescales, which have yet to be explained."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2008 on: November 20, 2017, 11:32:53 PM »
Not to state the obvious, but Hansen et al (2016)'s model assumes an ECS value (see the first image) compatible with that used in CMIP5, which is well below that demonstrated by Friedrich et al (2016) based on dynamical paleo data (see the second image).  Furthermore, Bakker et al. (2017) show that ice mass loss associated with 'deep uncertainty' for ice sheets indicates that significant hosing from Antarctica could begin as early as between 2030-2040 and from Greenland as early as 2040-2050; which per the third image from Hansen et al (2016) is associated with the line labeled '5-year doubling' which indicates an over 2 W/sq m increase in planetary energy imbalance by 2060-2070, which is not included in Friedrich et al (2016) GMSTA projections.  Thus, SSP5 baseline, may be nowhere near a worst case scenario when considering effective radiative forcing this century, if AIS and the GIS continue to lose ice mass in accordance with DeConto and Pollard (2016) for BAU conditions through at least 2050.
« Last Edit: November 20, 2017, 11:37:55 PM by AbruptSLR »
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2009 on: November 21, 2017, 06:17:37 PM »
With a hat-tip to jai, I provide extracts from the linked article entitled: "Ice Apocalypse".  Three key questions about this topic include:
(1) Were DeConto & Pollard too conservative when they only used one half the ice cliff collapse rate observed at Jakobshavn for the WAIS calculations?
(2) When will the ice cliff failure mechanisms begin in the WAIS?
(3) How much faster does marine ice-sheet instabilities occur as compared to ice-cliff instabilities?

https://grist.org/article/antarctica-doomsday-glaciers-could-flood-coastal-cities/

Extract: "A wholesale collapse of Pine Island and Thwaites would set off a catastrophe. Giant icebergs would stream away from Antarctica like a parade of frozen soldiers. All over the world, high tides would creep higher, slowly burying every shoreline on the planet, flooding coastal cities and creating hundreds of millions of climate refugees.

All this could play out in a mere 20 to 50 years — much too quickly for humanity to adapt.

The only place in the world where you can see ice-cliff instability in action today is at Jakobshavn glacier in Greenland, one of the fastest-collapsing glaciers in the world. DeConto says that to construct their model, they took the collapse rate of Jakobshavn, cut it in half to be extra conservative, then applied it to Thwaites and Pine Island.

But there’s reason to think Thwaites and Pine Island could go even faster than Jakobshavn.

Right now, there’s a floating ice shelf protecting the two glaciers, helping to hold back the flow of ice into the sea. But recent examples from other regions, like the rapidly collapsing Larsen B ice shelf on the Antarctic Peninsula, show that once ice shelves break apart as a result of warming, their parent glaciers start to flow faster toward the sea, an effect that can weaken the stability of ice further inland, too.

“If you remove the ice shelf, there’s a potential that not just ice-cliff instabilities will start occurring, but a process called marine ice-sheet instabilities,” says Matthew Wise, a polar scientist at the University of Cambridge.

This signals the possible rapid destabilization of the entire West Antarctic ice sheet in this century. “Once the stresses exceed the strength of the ice,” Wise says, “it just falls off.”"
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2010 on: November 21, 2017, 06:49:46 PM »
The area of the three dots in the attached image represent the relative sizes of the data output from CMIP3, CMIP5 and CMIP6.  Will climate scientists be able to find the one real pathway to future climate change that we will actually follow with all the imaginary pathways obscuring the truth?

Edit: I believe that similar comments could be made about how the IPCC AR process keeps too much chafe among its wheat; which then drags down reported averages for values such as ECS.
« Last Edit: November 21, 2017, 07:18:33 PM by AbruptSLR »
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2011 on: November 21, 2017, 07:14:13 PM »
The linked reference studies dynamical cloud response to aerosol forcing and concludes: "The dynamical cloud response is closely linked to the meridional displacement of the Hadley Cell that, in turn, is driven by changes in the cross-equatorial energy transport. In this way, the dynamical cloud changes act as a positive feedback on the meridional displacement of the Hadley Cell, roughly doubling the projected changes in cross-equatorial energy transport compared to that from the microphysical changes alone." 

Brian Soden and Eui-Seok Chung (2017), "The Large Scale Dynamical Response of Clouds to Aerosol Forcing" Journal of Climate", https://doi.org/10.1175/JCLI-D-17-0050.1

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-17-0050.1?utm_content=bufferaa6b0&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Abstract: "We use radiative kernels to quantify the instantaneous radiative forcing of aerosols and the aerosol-mediated cloud response in coupled ocean-atmosphere model simulations under both historical and future emission scenarios. The method is evaluated using matching pairs of historical climate change experiments with and without aerosol forcing and accurately captures the spatial pattern and global mean effects of aerosol forcing. We show that aerosol-driven changes in the atmospheric circulation induce additional cloud changes. Thus, the total aerosol-mediated cloud response consists of both local microphysical changes and non-local dynamical changes that are driven by hemispheric asymmetries in aerosol forcing. By comparing coupled and fixed-SST (sea surface temperature) simulations with identical aerosol forcing we isolate the relative contributions of these two components, exploiting the ability of prescribed SSTs to also suppress changes in the atmospheric circulation. The radiative impact of the dynamical cloud changes are found to be comparable in magnitude to that of the microphysical cloud changes, and act to further amplify the inter-hemispheric asymmetry of the aerosol radiative forcing. The dynamical cloud response is closely linked to the meridional displacement of the Hadley Cell that, in turn, is driven by changes in the cross-equatorial energy transport. In this way, the dynamical cloud changes act as a positive feedback on the meridional displacement of the Hadley Cell, roughly doubling the projected changes in cross-equatorial energy transport compared to that from the microphysical changes alone."

I provide this reference here because it supports the concept that past aerosols from East Asia (mostly China) has been suppressing the development of strong El Nino events during the 'faux hiatus' (see the attached image from the following linked article), and now that this anthropogenic aerosol is being cleaned-up we may well see a marked increase in Super El Nino events, which would in turn increase climate sensitivity.

https://andthentheresphysics.wordpress.com/2017/11/16/a-real-time-global-warming-index/
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2012 on: November 21, 2017, 08:19:29 PM »
The Global Carbon Project recently issued the attached image comparing the SSP scenarios vs the observed projected thru 2017 for the fossil fuel and land use change CO2 emissions.  This plot indicates that we are currently following the SSP5 Baseline pathway.
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2013 on: November 21, 2017, 08:48:21 PM »
Given that AR5 included no increased carbon-climate feedbacks from northern soils, the fact that the linked reference finds that this feedback mechanism is strong, helps to illustrate how far on the side of least drama that AR5 errs:

Koven et al. (2017), "Higher climatological temperature sensitivity of soil carbon in cold than warm climates", Nature Climate Change, doi:10.1038/nclimate3421

http://www.nature.com/articles/nclimate3421

Extract: "… we show that the climatological temperature control on carbon turnover in the top metre of global soils is more sensitive in cold climates than in warm climates and argue that it is critical to capture this emergent ecosystem property in global-scale models.

These results support projections of strong carbon-climate feedbacks from northern soils and demonstrate a method for ESMs to capture this emergent behavior."
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Re: Conservative Scientists & its Consequences
« Reply #2014 on: November 21, 2017, 11:47:46 PM »
While the linked reference applies to paleoclimate glacial conditions, the message that gradual increases in carbon dioxide can cause abrupt climate change, is not reassuring for our communal futures:

Xu Zhang et al. (2017), "Abrupt North Atlantic circulation changes in response to gradual CO2 forcing in a glacial climate state", Nature Geoscience, doi:10.1038/ngeo2974

http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2974.html

Abstract: "Glacial climate is marked by abrupt, millennial-scale climate changes known as Dansgaard–Oeschger cycles. The most pronounced stadial coolings, Heinrich events, are associated with massive iceberg discharges to the North Atlantic. These events have been linked to variations in the strength of the Atlantic meridional overturning circulation. However, the factors that lead to abrupt transitions between strong and weak circulation regimes remain unclear. Here we show that, in a fully coupled atmosphere–ocean model, gradual changes in atmospheric CO2 concentrations can trigger abrupt climate changes, associated with a regime of bi-stability of the Atlantic meridional overturning circulation under intermediate glacial conditions. We find that changes in atmospheric CO2 concentrations alter the transport of atmospheric moisture across Central America, which modulates the freshwater budget of the North Atlantic and hence deep-water formation. In our simulations, a change in atmospheric CO2 levels of about 15 ppmv—comparable to variations during Dansgaard–Oeschger cycles containing Heinrich events—is sufficient to cause transitions between a weak stadial and a strong interstadial circulation mode. Because changes in the Atlantic meridional overturning circulation are thought to alter atmospheric CO2 levels, we infer that atmospheric CO2 may serve as a negative feedback to transitions between strong and weak circulation modes."

See also the associated linked article entitled: "Scientists throw light on mysterious ice age temperature jumps"

https://phys.org/news/2017-06-scientists-mysterious-ice-age-temperature.html

Extract: "In a new study published today, the researchers show that rising levels of CO2 could have reached a tipping point during these glacial periods, triggering a series of chain events that caused temperatures to rise abruptly.

The findings, which have been published in the journal Nature Geoscience, add to mounting evidence suggesting that gradual changes such as a rising CO2 levels can lead to sudden surprises in our climate, which can be triggered when a certain threshold is crossed.

Previous studies have shown that an essential part of the natural variability of our climate during glacial times is the repeated occurrence of abrupt climate transitions, known as Dansgaard-Oeschger events.

These events are characterized by drastic temperature changes of up to 15°C within a few decades in the high latitudes of the Northern Hemisphere. This was the case during the last glacial period around 100,000 to 20,000 years ago.

It is commonly believed that this was a result of sudden floods of freshwater across the North Atlantic, perhaps as a consequence of melting icebergs.

Co-author of the study Professor Stephen Barker, from Cardiff University's School of Earth and Ocean Sciences, said: "Our results offer an alternative explanation to this phenomenon and show that a gradual rise of CO2 within the atmosphere can hit a tipping point, triggering abrupt temperature shifts that drastically affect the climate across the Northern Hemisphere in a relatively short space of time.

"These findings add to mounting evidence suggesting that there are sweet spots or 'windows of opportunity' within climate space where so-called boundary conditions, such as the level of atmospheric CO2 or the size of continental ice sheets, make abrupt change more likely to occur. Of course, our study looks back in time and the future will be a very different place in terms of ice sheets and CO2 but it remains to be seen whether or not Earth's climate becomes more or less stable as we move forward from here".

Using climate models to understand the physical processes that were at play during the glacial periods, the team were able to show that a gradual rise in CO2 strengthened the trade winds across Central America by inducing an El Nino-like warming pattern with stronger warming in the East Pacific than the Western Atlantic.

As a result there was an increase in moisture transport out of the Atlantic, which effectively increased the salinity and density, of the ocean surfaces, leading to an abrupt increase in circulation strength and temperature rise.

"This does not necessarily mean that a similar response would happen in the future with increasing CO2 levels, since the boundary conditions are different from the ice age," added by Professor Gerrit Lohmann, leader of the Paleoclimate Dynamics group at the Alfred Wegener Institute.

"Nevertheless, our study shows that climate models have the ability of simulating abrupt changes by gradual forcing as seen in paleoclimate data.""
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CDN_dude

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Re: Conservative Scientists & its Consequences
« Reply #2015 on: November 22, 2017, 06:18:20 PM »
Probably not fair to call this an instance of conservative scientific reticence since it is a new discovery, but it is another addition to the list of feedbacks not currently included in climate models.

"In the journal Nature Communications, researchers at The Ohio State University and their colleagues describe the discovery of the first known methane-producing microbe that is active in an oxygen-rich environment...
"We've always assumed that oxygen was toxic to all methanogens," said Kelly Wrighton, project leader and professor of microbiology at Ohio State. "That assumption is so far entrenched in our thinking that global climate models simply don't allow for methane production in the presence of oxygen. Our work shows that this way of thinking is outdated, and we may be grossly under-accounting for methane in our existing climate models."
...the researchers found traces of Candidatus Methanothrix paradoxum in more than 100 sites across North America, South America, Europe and Asia."

Read more at: https://phys.org/news/2017-11-pin-source-potent-greenhouse-gas.html#jCp"

https://www.nature.com/articles/s41467-017-01753-4

AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2016 on: November 22, 2017, 07:11:08 PM »
Probably not fair to call this an instance of conservative scientific reticence since it is a new discovery, but it is another addition to the list of feedbacks not currently included in climate models.

It can seem wrong to call-out conservative scientific reticence, because in general terms climate scientists are hard working & intelligent; and calling them out can be used by climate denialists to promote their own agendas.  However, if one thinks of reticent scientists as co-dependent enablers of elite decision makers who are addicted to providing the global socio-economic system with cheap fossil fuel energy then it be easier to understand how it is necessary to gradually nudge this co-dependent relationship into healthier behavior before key Earth Systems reach their tipping points.

For example, if it is true that elite decision makers want to keep the world socio-economic growth in a rapid growth pattern then we can experience both rapid global economic growth (SSP5) and high income inequality (SSP4) by further 'overshooting' the Earth's resources say by taping into Arctic resources as global warming melts the ice. But the attached image indicates that reticent climate scientists have not set-up the SSP scenarios that way.  Unfortunately, I do not believe that reticent scientists know how to free themselves from their co-dependent relationship which enables the elite decision makers to maintain their addiction to cheap energy.
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2017 on: November 23, 2017, 12:21:27 AM »
The linked SciAm article by Kate Marvel confirms that the net feedback from clouds is currently positive and may well become more positive with continued global warming.  This will result in more global warming than was previously anticipated for the same radiative forcing:

Kate Marvel (2017), "The Cloud Conundrum", Scientific American 317, doi:10.1038/scientificamerican1217-72

http://www.nature.com/scientificamerican/journal/v317/n6/full/scientificamerican1217-72.html
&
https://www.scientificamerican.com/article/will-changing-cloud-cover-accelerate-global-warming/

Brief: "To accurately predict how much warmer climate change will make the earth, scientists must determine the influence of clouds, which is significant.  Computer models have difficulty simulating the changing nature of clouds, but improved satellite data are providing some strong clues: high clouds are likely to get higher, cloudy and clear bands may shift from lower latitudes towards the poles, and clouds may become less icy and more watery.  Data indicate that the trends that amplify warming are strong and the trends that slow warming are weaker than anticipated."
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A-Team

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Re: Conservative Scientists & its Consequences
« Reply #2018 on: November 23, 2017, 02:22:21 AM »
Quote
since it is a new discovery, but it is another addition to the list of feedbacks not currently included in climate models.
Actually, it wasn't. Refs 6-10 review the prior history of discovery, starting in 2005. What they did here is a metagenomic assembly of the suspected species complex (meaning no attempt to grow it in pure culture). It proved to be an ordinary acetoclastic archaea, the only surprise being it had no discernible adaptations to aerobic conditions.

The authors appear to be microbial ecologists with minimal training in molecular biology or methane enzymology --  they merely looked at catalase and superoxide dismutase, rather than direct molecular 02 catalytic poisoning of metaloenzymes such as the nickel tetrapyrrole of coenzyme F430 in methyl coenzyme M reductase (MCR), the final step of methanogenesis in all archaea. (Note nitrogen fixation is also obligatorily sensitive to 02 according to whether the nitrogenase uses a molybdenum-iron, vanadium-iron or iron-iron cofactor.)

Nonetheless they hit upon what is the likeliest explanation: it is a standard obligate anaerobic archaea that somehow has found sheltered pockets in what otherwise is bulk oxic soil. (It is obviously uncompetitive to make one ATP per molecule of acetate when your aerobic neighbor is making a dozen.)

Quote
We suggest that rather than having special adaptations, surface methanogen activity may be confined to anoxic subfactions (e.g., microsites, soil aggregates, or particles) with locally depleted soil oxygen concentrations relative to otherwise overall oxic surrounding soils. This hypothesis is not without warrant, as anoxic microsites were shown to facilitate anaerobic metabolisms in bulk oxygenated soils (e.g., for denitrification, iron reduction) and particle-associated models explain methanogenesis in oxic lake waters.

From one tiny site, they were in no position to pursue the implications to the global climate carbon cycle. Indeed, the whole idea that a vast heterogeneous biological system could be globally modeled is preposterous -- there's more biological diversity in a teaspoon of swamp water than among all the mammals on the planet (eg mammoths and human average 85% identity at the amino acid sequence level).

Bogard, M. J. et al. Oxic water column methanogenesis as a major component of aquatic CH4 fluxes. Nat. Commun. 5, 5350 (2014).
CASArticlePubMed
Grossart, H. P., Frindte, K., Dziallas, C., Eckert, W. & Tang, K. W. Microbial methane production in oxygenated water column of an oligotrophic lake. Proc. Natl. Acad. Sci. USA 108, 19657–19661 (2011).
ADSCASArticlePubMedPubMed Central
Tang, K. W., McGinnis, D. F., Ionescu, D. & Grossart, H. P. Methane production in oxic lake waters potentially increases aquatic methane flux to air. Environ. Sci. Technol. Lett. 3, 227–233 (2016).
CASArticle
Teh, Y. A., Silver, W. L. & Conrad, M. E. Oxygen effects on methane production and oxidation in humic tropical forest soils. Glob. Chang. Biol. 11, 1283–1297 (2005).
ADSArticle
Angel, R., Matthies, D. & Conrad, R. Activation of methanogenesis in arid biological soil crusts despite the presence of oxygen. PLoS ONE 6, e20453 (2011).
« Last Edit: November 23, 2017, 03:36:22 AM by A-Team »

CDN_dude

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Re: Conservative Scientists & its Consequences
« Reply #2019 on: November 23, 2017, 03:35:48 AM »
Actually, it wasn't...

Ok thank you, you've done a much better job at putting that in context than the article. One of the perils as a non-scientist of relying too much on science journalism I guess.

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Re: Conservative Scientists & its Consequences
« Reply #2020 on: December 01, 2017, 04:44:55 PM »
I doubt that the SSP radiative forcing scenarios consider the influence of our aging infrastructure on natural gas leaks (see the map of gas leaks in the USA since 2010):

Title: "A map of $1.1 billion in natural gas pipeline leaks"

http://www.hcn.org/articles/infographic-a-map-of-leaking-natural-gas-pipelines-across-the-nation

Extract: "In seven years, pipeline incidents have killed nearly 100 people nationwide."
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Re: Conservative Scientists & its Consequences
« Reply #2021 on: December 02, 2017, 05:28:34 AM »
The well casing failure rate of every natural gas well ever drilled is 100% on a 200 year timeline.
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Re: Conservative Scientists & its Consequences
« Reply #2022 on: December 02, 2017, 06:51:17 AM »
"The well casing failure rate of every natural gas well ever drilled is 100% on a 200 year timeline."

Since we don't have stats for 200 yr, are you basin this on failure rates for casings or ... ?

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Re: Conservative Scientists & its Consequences
« Reply #2023 on: December 02, 2017, 04:08:44 PM »
"The well casing failure rate of every natural gas well ever drilled is 100% on a 200 year timeline."

Since we don't have stats for 200 yr, are you basin this on failure rates for casings or ... ?

sidd

Mostly industry journal studies but also some interviews with industry people.  The fact is that wells are made of cement and steel and capped (if properly) with cement.  Cement and steel fail when left in the ground and cement in this environment is not intended to last for very long forever.  http://tcgasmap.org/media/Casement%20Failure%20in%20Gas%20Wells.pdf
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Re: Conservative Scientists & its Consequences
« Reply #2024 on: December 02, 2017, 04:41:00 PM »
"The well casing failure rate of every natural gas well ever drilled is 100% on a 200 year timeline."

Since we don't have stats for 200 yr, are you basin this on failure rates for casings or ... ?

sidd
Someone once told me that while the cement the Romans used is often in fine fettle even today, modern cement has a maximum life of about 150 years as various chemical reactions continue (though slowly) even after it is set.

Even the water pipes made by the Germans for their water systems (ductile iron) are only expected to last a maximum of 200 years, and only then if the water flowing through them and the dirt in which they are laid are inert chemically.

In my old UK industrial city, they are replacing many many old gas mains from the 1970's. They are decaying through contact with trace chemicals in the clay soils..
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Re: Conservative Scientists & its Consequences
« Reply #2025 on: December 02, 2017, 06:28:26 PM »
In 2010 Peoples Gas received approval to implement an accelerated plan to replace aging gas mains in the city of Chicago at a cost of $2.6 billion. The utility had been working for the previous 2 decades to replace the mains and it had become clear the rate of replacement was too slow. In 2017 the utility got approval to accelerate the accelerated plan to complete the remaining 2000 miles of rapidly aging gas mains that are failing at an alarming rate. This project is now forecast to be completed by 2040 at a cost of $300 million per year. The total cost of replacement is now expected to top $6 billion.

http://www.plasticsnews.com/article/20170512/NEWS/170519964/chicago-gas-pipe-replacement-costs-continue-to-climb

These kinds of ambitious infrastructure investments are intended to support our built structures (in this case the 3rd largest city in the U.S.) and are difficult to finance even in one of the wealthiest countries in the world. Once in place, this fixed infrastructure which represents a large portion of accumulated wealth of a nation is expected to reap benefits for the region as a whole out into the distant future. You do not get any 'take backs' when complete and you better hope this long term investment of precious wealth took sufficiently into account all of the factors affecting that distant future.

No one bothered to ask what role natural gas would or should play in 2050 or 2080!!!
« Last Edit: December 03, 2017, 03:23:09 PM by Shared Humanity »

sidd

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Re: Conservative Scientists & its Consequences
« Reply #2026 on: December 02, 2017, 09:29:51 PM »
Thanks for the casement reference, Mr. Mitchell.

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Re: Conservative Scientists & its Consequences
« Reply #2027 on: December 02, 2017, 10:09:14 PM »
Here in South-West Ontario, Canada space heating is predominantly natural gas. The cost of replacing all of those heating systems will be phenomenal, and we keep putting them into new buildings. This is part of the massive inertia embedded in our physical systems. Cutting fossil fuel use at the margin is relatively easy, but when you start getting into the real guts of the energy system things get much harder very quickly. The city of Toronto gave up its rail marshalling yards and docks to condo developers, pretty much destroying those future options.

At least here in Kitchener-Waterloo we have a new light rail (when Bombardier gets around to delivering the trains!).

As long as the scientists fail to deliver the wake up call, governments will keep making stupid decisions which lock them in to fossil fuel usage for many decades.

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Re: Conservative Scientists & its Consequences
« Reply #2028 on: December 03, 2017, 04:53:59 AM »
Thanks for the casement reference, Mr. Mitchell.

sidd

sure thing, thanks for the reminder, haven't looked at it for a number of years.  The thing is, from a geological perspective, I can only muse as to the long-term impact of methane emissions from this additional source over hundreds of years.  It seems clear that we will have to monitor and repair these wells in the future to prevent massive fugitive methane leakage.
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Re: Conservative Scientists & its Consequences
« Reply #2029 on: December 03, 2017, 03:19:50 PM »


As long as the scientists fail to deliver the wake up call, governments will keep making stupid decisions which lock them in to fossil fuel usage for many decades.

Sadly yes. Good science would inform good policy decisions.

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Re: Conservative Scientists & its Consequences
« Reply #2030 on: December 03, 2017, 05:47:54 PM »


As long as the scientists fail to deliver the wake up call, governments will keep making stupid decisions which lock them in to fossil fuel usage for many decades.

Sadly yes. Good science would inform good policy decisions.
Governments are ignoring or blatantly denying the science. It is not appropriate to blame the scientists.

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Re: Conservative Scientists & its Consequences
« Reply #2031 on: December 03, 2017, 05:57:31 PM »
rboyd: If they would not use natural gas. And you would be talking on the scale of a medium city. How would you heat them ?

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Re: Conservative Scientists & its Consequences
« Reply #2032 on: December 03, 2017, 07:31:32 PM »
rboyd: If they would not use natural gas. And you would be talking on the scale of a medium city. How would you heat them ?
You are right to point out that bottleneck, that has had me scratching my head for some time. In the UK nearly all housing relies on gas for hot water and heating - the "combi boiler". In my wanderings all down eastern europe and scandinavia district heating was the norm for towns and cities, powered by hot water from waste heat from power stations  - even though after the collapse of the Warsaw Pact many were in dire straits.

As yet I have seen very little discussion on this.
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Re: Conservative Scientists & its Consequences
« Reply #2033 on: December 03, 2017, 07:46:26 PM »
Electricity is an option. A friend of mine heats his home with electricity. It's something with stones in it, they warm up when the electricity price is low. And they release that heat during the day. But it takes a lot of electricity.

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Re: Conservative Scientists & its Consequences
« Reply #2034 on: December 03, 2017, 09:02:08 PM »


As long as the scientists fail to deliver the wake up call, governments will keep making stupid decisions which lock them in to fossil fuel usage for many decades.

Sadly yes. Good science would inform good policy decisions.
Governments are ignoring or blatantly denying the science. It is not appropriate to blame the scientists.

The fundamental problem of our situation is that modern global society is built-on, and has become addicted to, relatively cheap power (which is currently dominated by fossil fuel) and to kick this fossil fuel addiction it is espoused (by the addicted) as requiring a pretty big kick (more than Hansen's warning & apparently more than consensus science's warnings).  Per the linked articles/study the addicted use a 'keystone dominoes' strategy to raise doubts on targeted issues in order to undermine public confidence in the vast body of evidence that effective action to fight climate change is needed sooner rather than later.

With regards to consensus climate science, the addicted have bullied those preparing both the RCP and the SSP radiative forcing scenarios to adopt ESLD assumptions about key issues including:
(a) Assuming high effectiveness of future regulations in order to limit assumed ranges of anthropogenic emissions;

(b) Relying only on published information which tends to marginalize new cutting-edge information, by either saying it missed the cut-off date, or by blending it with old out-of-date information; and

(c) Assuming lower global population projections than current UN projections support.

With regards to decision makers, the addicted have bullied those supporting progressively increasing Carbon Fee and Dividend programs that would make fossil fuels accountable for the damage that they cause by making statements like:

(a) The world is an arena and not a community, thus the Paris Accord should not even promote globally coordinated national Carbon Fee and Dividend plans;

(b) The Kyoto Protocol (signed Dec 11 1997; which was early enough to have allowed a cost effective transition infrastructure that support conservation and reuse) was only a joke, because by the 'Shock Doctrine' espoused by Milton Friedman et al people/addicts will only make a change when they have received a sufficient shock (like bottoming out); and

(c) Implementation of such plans would increase inefficient bureaucracy, thus we can never present the global market place with the true cost of fossil fuel and let the 'invisible hand of capitalism' promote more sustainable options.

While the over 7.5 billion current world population are their adopted leaders are the true addicts, nevertheless ESLD (err on the side of least drama) scientist act like co-dependent facilitators of that those addicts by not presenting sufficient warnings at Kyoto in order to allow for a smooth transition to a more sustainable global economy include the widespread implementation of national Carbon Fee and Dividend plans together with appropriate regulations and research funds for both sustainable technology and climate science:

Title: "New study uncovers the 'keystone domino' strategy of climate denial"

https://www.theguardian.com/environment/climate-consensus-97-per-cent/2017/nov/29/new-study-uncovers-the-keystone-domino-strategy-of-climate-denial

Extract: "The body of evidence supporting human-caused global warming is vast – too vast for climate denial blogs to attack it all. Instead they focus on what a new study published in the journal Bioscience calls “keystone dominoes.” These are individual pieces of evidence that capture peoples’ attention, like polar bears. The authors write:

These topics are used as “proxies” for AGW [human-caused global warming] in general; in other words, they represent keystone dominoes that are strategically placed in front of many hundreds of others, each representing a separate line of evidence for AGW. By appearing to knock over the keystone domino, audiences targeted by the communication may assume all other dominoes are toppled in a form of “dismissal by association.”

Basically, if these bloggers can create the perception that the science underlying polar bear or Arctic sea ice vulnerability to climate change is incorrect, their readers will assume that all of climate science is fatally flawed. And blogs can be relatively influential – surveys have shown that blog readers trust them more than traditional news and information sources."

Also see the article entitled: "Climate change and polar bears: deniers de-bunked"

http://www.rcinet.ca/en/2017/12/01/climate-change-and-polar-bears-deniers-de-bunked/

Extract: "The study says that climate denial involves a complex web of blogs, Facebook, twitter, and a variety of corporate interests, conservative foundations and think tanks.

Lead author of the report is NIOO-KNAW researcher Jeff Harvey (Netherlands Institute of Ecology) and co-authored by an international group of respected scientists.

Harvey, quoted by the science website Phys.Org, said, We found a major gap between the facts from scientific literature and the science-based blogs on the one hand, and the opinions aired in climate change-denying blogs on the other,” says Harvey. “It’s a very dangerous gap, as these blogs are read by millions.”"

Also see:
Jeffrey A. Harvey et al. (2017), "Internet Blogs, Polar Bears, and Climate-Change Denial by Proxy", BioScience, bix133, https://doi.org/10.1093/biosci/bix133

https://academic.oup.com/bioscience/advance-article/doi/10.1093/biosci/bix133/4644513

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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2035 on: December 03, 2017, 10:51:18 PM »
Consensus climate scientists are correct to note that: "Certain sorts of people are very fond of telling climate scientists that climate has always changed, as if we weren't the ones who figured that out."  However, they should also note relevant information like:

(a) When one takes a static interpretation of paleo data ECS looks to be around 3C; but when one takes a more accurate dynamical interpretation it looks to be around 4 to 4.5C; and

(b) While the current atmospheric CO2 concentration of about 406.8ppm (see first image) is well above the approximately 325ppm concentration during the Eemian (MIS 5 peak) about 130 kya (see the second image); the CO2e (assuming a GWP100 for methane of 35 and input from ozone) is over 530ppm.

Consensus climate scientists should give the public a more complete understanding of our true climate risks than what they are currently managing to convey to the public and to decision makers.
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TerryM

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Re: Conservative Scientists & its Consequences
« Reply #2036 on: December 04, 2017, 01:06:21 AM »

ASLR

I wonder if someone could take your first chart, the monthly CO2 at Mauna Loa, and superimpose the monthly global temperature (at a proper scale). I don't know if the feedback is rapid enough to be captured at this scale, but if it is, the chart might disturb some in the denialist community. If not, perhaps annual averages of both.


Terry

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Re: Conservative Scientists & its Consequences
« Reply #2037 on: December 04, 2017, 01:35:23 AM »

ASLR

I wonder if someone could take your first chart, the monthly CO2 at Mauna Loa, and superimpose the monthly global temperature (at a proper scale). I don't know if the feedback is rapid enough to be captured at this scale, but if it is, the chart might disturb some in the denialist community. If not, perhaps annual averages of both.


Terry

Terry,

I have poor graphical skills, and I have no idea what would or would not disturb denialists, and there is at least a 7-year lag-time on fast feedback mechanisms; nevertheless, I provide the attached projection (for 2017) by Gavin using GISTEMP data through September, and I note that using GISTEMP LOTI values through October the 12-month running average Global Mean Surface Temperature Anom, GMSTA, baselined to pre-industrial was 1.159C.  If this trend continues we may reach 1.5C by 2024.

Best,
ASLR
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jai mitchell

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Re: Conservative Scientists & its Consequences
« Reply #2038 on: December 06, 2017, 08:47:35 PM »
https://www.nature.com/articles/nature24672

Abstract

Climate models provide the principal means of projecting global warming over the remainder of the twenty-first century but modelled estimates of warming vary by a factor of approximately two even under the same radiative forcing scenarios. Across-model relationships between currently observable attributes of the climate system and the simulated magnitude of future warming have the potential to inform projections. Here we show that robust across-model relationships exist between the global spatial patterns of several fundamental attributes of Earth’s top-of-atmosphere energy budget and the magnitude of projected global warming. When we constrain the model projections with observations, we obtain greater means and narrower ranges of future global warming across the major radiative forcing scenarios, in general. In particular, we find that the observationally informed warming projection for the end of the twenty-first century for the steepest radiative forcing scenario is about 15 per cent warmer (+0.5 degrees Celsius) with a reduction of about a third in the two-standard-deviation spread (−1.2 degrees Celsius) relative to the raw model projections reported by the Intergovernmental Panel on Climate Change. Our results suggest that achieving any given global temperature stabilization target will require steeper greenhouse gas emissions reductions than previously calculated.

video abstract here:
Haiku of Past Futures
My "burning embers"
are not tri-color bar graphs
+3C today

AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2039 on: December 08, 2017, 12:35:46 AM »
https://www.nature.com/articles/nature24672

Abstract

Climate models provide the principal means of projecting global warming over the remainder of the twenty-first century but modelled estimates of warming vary by a factor of approximately two even under the same radiative forcing scenarios. Across-model relationships between currently observable attributes of the climate system and the simulated magnitude of future warming have the potential to inform projections. Here we show that robust across-model relationships exist between the global spatial patterns of several fundamental attributes of Earth’s top-of-atmosphere energy budget and the magnitude of projected global warming. When we constrain the model projections with observations, we obtain greater means and narrower ranges of future global warming across the major radiative forcing scenarios, in general. In particular, we find that the observationally informed warming projection for the end of the twenty-first century for the steepest radiative forcing scenario is about 15 per cent warmer (+0.5 degrees Celsius) with a reduction of about a third in the two-standard-deviation spread (−1.2 degrees Celsius) relative to the raw model projections reported by the Intergovernmental Panel on Climate Change. Our results suggest that achieving any given global temperature stabilization target will require steeper greenhouse gas emissions reductions than previously calculated.

Here is a little more information on this reference:

Brown & Caldeira (2017), "Greater future global warming inferred from Earth's recent energy budget", Nature (2017). nature.com/articles/doi:10.1038/nature24672

See also:

Title: "More-severe climate model predictions could be the most accurate: study"

https://phys.org/news/2017-12-more-severe-climate-accurate.html

Extract: ""It makes sense that the models that do the best job at simulating today's observations might be the models with the most reliable predictions," Caldeira added. "Our study indicates that if emissions follow a commonly used business-as-usual scenario, there is a 93 percent chance that global warming will exceed 4 degrees Celsius (7.2 degrees Fahrenheit) by the end of this century. Previous studies had put this likelihood at 62 percent." "
« Last Edit: December 19, 2017, 10:08:40 PM by AbruptSLR »
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2040 on: December 15, 2017, 05:10:13 PM »
When the SSP scenarios were developed it looks like the climate scientists ignored the findings of social scientists such as: the "smart idiot" effect and political corruption due to influence from the fossil fuel industry.  If climate scientists want to develop realistic Shared Socioeconomic Pathway scenarios they should stop living within information bubbles about likely human behavior during the Anthropocene:

The linked article entitled: "Research shows that certain facts can still change conservatives’ minds", states: "But it’s political corruption, not public opinion that’s blocking American climate policy".

https://www.theguardian.com/environment/climate-consensus-97-per-cent/2017/dec/14/research-shows-that-certain-facts-can-still-change-conservatives-minds

Extract: "There’s a debate between social scientists about whether climate change facts can change peoples’ minds or just polarize them further. For example, conservatives who are more scientifically literate are less worried about global warming. In essence, education arms them with the tools to more easily reject evidence and information that conflicts with their ideological beliefs. This has been called the “smart idiot” effect and it isn’t limited to climate change; it’s also something we’re seeing with the Republican tax plan.

However, other research has shown that conservatives with higher climate-specific knowledge are more likely to accept climate change – a result that holds in many different countries. For example, when people understand how the greenhouse effect works, across the political spectrum they’re more likely to accept human-caused global warming.

A recent Gallup poll also found American concern about climate change at an all-time high. But lack of public support isn’t the problem. For example, 62% of Trump voters support carbon pollution taxes and/or regulations. And of course while there is tremendous public support for many gun control policies, Republicans in Congress refuse to vote for those policies. Sadly, the party is now morally and intellectually bankrupt, completely controlled by special interests and indifferent to the opinions of their constituents.

To summarize, most Americans are aware that humans are causing global warming, and across the political spectrum they support climate policies. Communicating facts isn’t necessarily polarizing; in fact certain information like the existence of the 97% expert climate consensus actually decreases polarization and increases acceptance of climate science and policies. That’s all important and good news, but until the fossil fuel industry no longer controls the political party in power, America won’t be able to implement national climate policies."
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2041 on: December 15, 2017, 05:35:29 PM »
The linked open access reference indicates that land use change will likely play a 50% larger role in future radiative forcing scenarios than previously assumed by the SSP scenarios:

Fuchs, R., Prestele, R., and Verburg, P. H.: A global assessment of gross and net land change dynamics for current conditions and future scenarios, Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2017-121, in review, 2017.

https://www.earth-syst-dynam-discuss.net/esd-2017-121/
&
https://www.earth-syst-dynam-discuss.net/esd-2017-121/esd-2017-121.pdf

Abstract. The consideration of gross land changes, meaning all area gains and losses within a pixel or administrative unit (e.g. country), plays an essential role in the estimation of total land changes. Gross land changes affect the magnitude of total land changes, which feeds back to the attribution of biogeochemical and biophysical processes related to climate change in Earth System Models. Global empirical studies on gross land changes are currently lacking. Whilst the relevance of gross changes for global change has been indicated in the literature, it is not accounted for in future land change scenarios. In this study, we extract gross and net land change dynamics from large-scale and high-resolution (30–100 m) remote sensing products to create a new global gross and net change dataset. Subsequently, we developed an approach to integrate our empirically derived gross and net changes with the results of future simulation models, by accounting for the gross and net change addressed by the land use model and the gross and net change that is below the resolution of modelling. Based on our empirical data, we found that gross land change within 0.5-degree grid cells were substantially larger than net changes in all parts of the world. As 0.5-degree grid cells are a standard resolution of Earth System Models, this leads to an underestimation of the amount of change. This finding contradicts earlier studies, which assumed gross land changes to appear in shifting cultivation areas only. Applied in a future scenario, the consideration of gross land changes led to approximately 50 % more land changes globally compared to a net land change representation. Gross land changes were most important in heterogeneous land systems with multiple land uses (e.g. shifting cultivation, smallholder farming, and agro-forestry systems). Moreover, the importance of gross changes decreased over time due to further polarization and intensification of land use. Our results serve as empirical database for land change dynamics that can be applied in Earth System Models and Integrated Assessment Models.


Extract: "In this study, we could show that that, based on empirical data, gross land changes occur globally in every world region. This finding contradicts earlier studies, which assumed gross land changes to appear in shifting cultivation areas only. Applied to our future reference scenario, net land changes led globally to an average of 0.92% area change per year, while for gross land changes the average change rate was 1.35% per year. This is an increase of roughly 50% compared to the net change approach.  Empirical data contributed ca. 80% of changes in the future scenario we used. This highlights the importance of accounting for sub-pixel processes in global assessments. In our scenario, gross land changes appeared in regional patterns, most dominant in Eastern Europe, Turkey, the Sahel zone, the United States and development countries in transition, like the BRICS states (Brazil, Russia, India, China and South Africa). Large-scale and high-resolution remote sensing data was crucial for this kind of assessment. This highlights the increasing importance of land related remote sensing data in global assessments. With our approach, it is possible to further decrease uncertainties in land changes dynamics and related land atmosphere fluxes in ESMs.  This again, helps to improve accuracies for future mitigation and adaptation scenarios."
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2042 on: December 19, 2017, 10:10:29 PM »
Brown & Caldeira (2017), "Greater future global warming inferred from Earth's recent energy budget", Nature (2017). nature.com/articles/doi:10.1038/nature24672

Apparently, Brown & Caldeira (2017)'s findings indicate a most likely value of ECS of 3.7C:
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2043 on: December 20, 2017, 10:31:41 PM »
Climate scientists have a lot of different metrics for measuring climate sensitivity, and the linked reference discusses such a metric that they call Inferred Effective Climate Sensitivity, (ECSinf), which they determine for combined radiative forcing and ocean heat content on both an energy balance model and a stochastic model.  Then they proceed to question the relevance of Proistosescu and Huybers (2017)'s [hereinafter PH17] calculation of Equilibrium Climate Sensitivity, ECS, based on both Instantaneous Climate Sensitivity, ICS, and slow response contributions taken from the CMIP5 models.  Skeie et al (2017) question PH17's measure of ECS as they say that the slow response contribution will not manifest itself within the timeframe of the IPCC's 2C limit.  However, this is clearly an inappropriate comment from Skeie et al (2017) as the CMIP5 models already show that slow response contribution has already become active due to the 267 years of anthropogenic warming since 1750.

Skeie, R. B., Berntsen, T., Aldrin, M., Holden, M., and Myhre, G.: Climate sensitivity estimates – sensitivity to radiative forcing time series and observational data, Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2017-119, in review, 2017.

https://www.earth-syst-dynam-discuss.net/esd-2017-119/
&
https://www.earth-syst-dynam-discuss.net/esd-2017-119/esd-2017-119.pdf

Abstract. Inferred Effective Climate Sensitivity (ECSinf) is estimated using a method combining radiative forcing (RF) time series and several series of observed ocean heat content (OHC) and near-surface temperature change in a Bayesian-framework using a simple energy balance model and a stochastic model. The model is updated compared to our previous analysis by using recent forcing estimates from IPCC, including OHC data for the deep ocean, and extending the time series to 2014. The mean value of the estimated ECSinf is 2.0 °C, with a 90 % credible interval of 1.2–3.1 °C. The mean estimate has recently been shown to be consistent with the higher values for the equilibrium climate sensitivity estimated by climate models. We show a strong sensitivity of the estimated ECSinf to the choice of a priori RF time series, excluding pre-1950 data and the treatment of OHC data. Sensitivity analysis performed by merging the upper (0–700 m) and the deep ocean OHC or using only one OHC data set (instead of four in the main analysis), both give an enhancement the mean ECSinf by about 50 % from our best estimate.

Extract: "Our ECSinf posterior mean was 2.0°C with 90 % C.I. of 1.2 to 3.1°C. This is consistent with a mean ECS of 2.9°C (Armour, 2017), which compares reasonably well with climate model estimates (Andrews et al., 2012; Forster et al., 2013). A final remark is that it is not obvious that the true ECS is a more relevant metric for the climate sensitivity than the ECSinf in a policy context (i.e. the Paris agreement). The United Nations Framework Convention on Climate Change (UNFCCC) has not adopted a pre-defined definition of GMST and the stronger long-term feedbacks found in analysis of CMIP5 simulations (Proistosescu and Huybers, 2017) operates on a time scale longer than the timescale for reaching 2°C."
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2044 on: December 26, 2017, 05:37:27 PM »
The linked article indicates that the scientific consensus on climate change has shifted to greater drama (than as stated in AR5) in the past year; however, it is my belief that this consensus is not shifting fast enough to prevent a socio-economic collapse circa 2050-2060:

Title: "Climate Change Is Happening Faster Than Expected, and It’s More Extreme"

https://insideclimatenews.org/news/26122017/climate-change-science-2017-year-review-evidence-impact-faster-more-extreme

Extract: "In the past year, the scientific consensus shifted toward a grimmer and less uncertain picture of the risks posed by climate change.

The Royal Society published a compendium of how the science has advanced, warning that it seems likelier that we've been underestimating the risks of warming than overestimating them.

The most ominous of its chapters addressed the risks of surprises like "tipping points" or "compound extremes"—sucker punches, combination punches, and even knockout punches. "The more the climate changes, the greater the potential for these," it said.

"Uncertainty is not our friend here," said Penn State climate scientist Michael Mann."

Edit, see also:

Title: "Climate updates: progress since the fifth Assessment Report (AR5) of the IPCC"

https://royalsociety.org/topics-policy/publications/2017/climate-updates/
&
https://royalsociety.org/~/media/policy/Publications/2017/27-11-2017-Climate-change-updates-report.pdf

Extract: "One important advance is that it is now known that as the climate warms it becomes less effective at emitting heat to space, mainly as a result of regional variations in surface warming. This means that climate sensitivity derived from historical data (which typically fails to fully represent regional areas that may be warmer or cooler than the average) gives an underestimate of the value for high carbon dioxide atmospheres. It is also now clear that the very slow changes in patterns of ocean surface warming are inadequately represented in time varying global climate models resulting in an underestimate of climate sensitivity.

Growing understanding of the complex, non-linear factors determining climate sensitivity is leading to improvements in methodologies for estimating it. A value below 2°C for the lower end of the likely range of equilibrium climate sensitivity now seems less plausible."
« Last Edit: December 26, 2017, 10:37:31 PM by AbruptSLR »
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2045 on: December 26, 2017, 06:29:35 PM »
The linked reference warns about the risks of heat stress by 2070-2080 when following RCP 8.5 (which is much earlier than previously assumed by climate scientists); however, their results do not consider ice-climate feedback:

Ethan David Coffel et al. Temperature and humidity based projections of a rapid rise in global heat stress exposure during the 21st century, Environmental Research Letters (2017). DOI: 10.1088/1748-9326/aaa00e

http://iopscience.iop.org/article/10.1088/1748-9326/aaa00e/meta

Abstract: "As a result of global increases in both temperature and specific humidity, heat stress is projected to intensify throughout the 21st century. Some of the regions most susceptible to dangerous heat and humidity combinations are also among the most densely populated. Consequently, there is the potential for widespread exposure to wet bulb temperatures that approach and in some cases exceed postulated theoretical limits of human tolerance by mid- to late-century. We project that by 2080 the relative frequency of present-day extreme wet bulb temperature events could rise by a factor of 100–250 (approximately double the frequency change projected for temperature alone) in the tropics and parts of the mid-latitudes, areas which are projected to contain approximately half the world's population. In addition, population exposure to wet bulb temperatures that exceed recent deadly heat waves may increase by a factor of five to ten, with 150–750 million person-days of exposure to wet bulb temperatures above those seen in today's most severe heat waves by 2070–2080. Under RCP 8.5, exposure to wet bulb temperatures above 35 °C—the theoretical limit for human tolerance—could exceed a million person-days per year by 2080. Limiting emissions to follow RCP 4.5 entirely eliminates exposure to that extreme threshold. Some of the most affected regions, especially Northeast India and coastal West Africa, currently have scarce cooling infrastructure, relatively low adaptive capacity, and rapidly growing populations. In the coming decades heat stress may prove to be one of the most widely experienced and directly dangerous aspects of climate change, posing a severe threat to human health, energy infrastructure, and outdoor activities ranging from agricultural production to military training."

See also:

Title: "From U.S. South to China, heat stress could exceed human endurance"

https://phys.org/news/2017-12-south-china-stress-human.html

Extract: "Lab experiments have shown wet-bulb readings of 32 degrees Celsius are the threshold beyond which many people would have trouble carrying out normal activities outside. This level is rarely reached anywhere today. But the study projects that by the 2070s or 2080s the mark could be reached one or two days a year in the U.S. southeast, and three to five days in parts of South America, Africa, India and China. Worldwide, hundreds of millions of people would suffer. The hardest-hit area in terms of human impact, the researchers say, will probably be densely populated northeastern India."
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2046 on: December 29, 2017, 07:45:11 PM »
The linked reference warns against "… naïve and superficial interpretations of power spectra"; which is relevant to the attached image from Gavin Schmidt's Twitter website, with the following associated text message.  This indicates that AR5's interpretation of the illustrated power spectra, of surface temperatures, may very likely err on the side of least drama (e.g. MIS 11c is outside of the power spectra, but AR5 does not address such Super Interglacials):

Eds: Crucifix M, de vernal A, Franzke C & von Gunten L (2017), "Centennial to Millennial Climate Variability", Past Global Changes Magazine, vol. 25(3), 131-166,

http://pastglobalchanges.org/products/pages-magazine/11504

Extract: "We are thus left with the difficult task of quantifying the amplitude of centennial variability and to understand its causes. Some of the challenges bear on the experts in the collection and analysis of paleoclimate data. Examples taken from marine records, sea ice and tree rings highlight the unfinished path still to accomplish to separate climate from non-climate variability in paleoclimate records. We should thus be wary of naive and superficial interpretations of power spectra. On the other hand, explanations for the causes of centennial variability generate their share of heated debates.

As we know, the climate system is complex enough to generate its own internal oscillations, like the El-Niño Southern Oscillations or Dansgaard-Oeschger events. There is no reason not to have such modes in the centennial band. Dijkstra and Von der Heydt (p. 150) provide one such example.

Besides, variability emerging from the chaos of atmospheric and oceanic motion may also propagate upwards and downwards throughout the frequency spectrum to produce what we know as the background spectrum."

Text message for the attached image:

"Gavin Schmidt ‏Verified account @ClimateOfGavin Dec 21

Replying to @Balinteractive @curryja and 2 others

Please show me where decadal or multi-decadal variability in the real world (black lines) is outside the bounds of the model ensemble (colors) (AR5 WG1 fig 9.33)"
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2047 on: December 29, 2017, 11:47:17 PM »
This is just a quick post to remind people that the CMIP5 projections do not consider freshwater hosing events; however, Antarctic ice shelves have lost so much ice mass in recent decades that Hansen's ice-climate positive feedback mechanism is already being activated even without a large SLR contribution from Antarctica.

In my opinion this initiation of the ice-climate feedback mechanism is already contributing to an increase in the positive nature of the net cloud feedback, by slowing the MOC and thus increasing the net surface temperatures of the tropical ocean regions (which increases evaporation and deep atmospheric convection, which both increases the average height of clouds and moves the net tropical cloud cover poleward; which resulting in increased solar radiation on the tropical oceans).

Edit: The attached image illustrates the extent of recent (1994-2012) ice mass loss from Antarctic ice shelves.
« Last Edit: December 30, 2017, 12:02:17 AM by AbruptSLR »
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AbruptSLR

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Re: Conservative Scientists & its Consequences
« Reply #2048 on: December 31, 2017, 04:10:40 PM »
The linked Bloomberg op/ed piece recommends that scientists stop sugar coating their climate change (/environmental) message to the public.  I am posting this piece in this thread because I believe that the same advise can be offered to cutting-edge climate scientists w.r.t. to the message that they convey to consensus climate scientists.  Furthermore, in this regard, I plan to make several follow-up posts about how consensus climate scientists do not yet fully appreciate the seriousness of our collective situation.

Title: "People Can Handle the Truth About the Environment"

https://www.bloomberg.com/view/articles/2017-12-27/people-can-handle-the-truth-about-the-environment

Extract: "Some scientists think that humans can’t handle the truth about the damage they are doing to the environment -- that findings must be sugar-coated lest people lose the hope needed to act.

They should listen to psychologists and stop holding back.

Earlier this year, the journalist David Wallace-Wells examined some of the more extreme possible consequences of climate change, including collapsing food supplies, perpetual war and extreme heat making cities uninhabitable. Climate skeptics were predictably outraged, but some scientists also criticized the article for scaring people. "The most motivating emotions,” they claimed, “are worry, interest and hope.” Fear, they argued, tends to make people disengage and dismiss the issue.

Is that true? Not really. In a recent paper, the psychologist Daniel Chapman and co-authors argue that this oversimplifies how emotions influence our actions.  They aren't like buttons that can be pushed to trigger a certain behavior. Rather, they act in a subtle way, tagging information in our memory with emotive tones, or influencing how we might seek out further information. As a result, any simple recipe for emotional persuasion -- say, being negative or positive -- is unlikely to have the desired effect.

So how to get the message across? In an interview, Chapman said it would be a big mistake to downplay frightening issues just because the public might not like to hear about them. What’s important is to provide other information that can help readers relate the news to their own lives, and to identify practical avenues by which they might respond. People tend to care more about issues that have repercussions locally, both in time and geography. So if such potential repercussions exist, communications should emphasize them.

To U.S. readers, for example, ecological Armageddon sounds far off, as do insects in Germany. Yet the findings suggest that states such as California, Iowa or Nebraska could face similar declines in insect populations, with severe consequences for agriculture. In addition, people need some feeling of agency: Strategic changes in agricultural policy and practice, for instance, could help the insects recover.

Chapman mentioned one final thing, perhaps the most important: authenticity. People want to be treated with respect and given balanced information, and they’ll turn away if they feel they’re being sold something. Granted, balance won’t necessarily change the minds of the most ideologically fixated readers, but they’re in the minority. “A much larger portion of the public,” Chapman said, “is either disinterested, unaware or inundated with too much other information.”

These people can handle frightening news, no softening needed, if offered some help in seeing how it might touch their lives and what they can do about it."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Hefaistos

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Re: Conservative Scientists & its Consequences
« Reply #2049 on: December 31, 2017, 07:07:56 PM »
I live in a mid-sized town in Sweden (Uppsala) where practically all hot water for heating purposes is centrally produced in a heating station. Currently it runs on oil and waste, but it's being converted to run on biomass, i.e. wood. This is a pet project for environmentally conscious politicians.
Interestingly, Kevin Anderson, who is a visiting professor in Uppsala for one year, hasn't been positive at all about this project. Seemingly for a good reason, according to an article in the Guardian about critical scientists:

"Policies aimed at limiting climate change by boosting the burning of biomass contain critical flaws that could actually damage attempts to avert dangerous levels of global warming in the future.
...
giant power stations, ...are increasingly abandoning gas or coal as power sources and are instead turning to the burning of wood, usually in the form of pellets imported from other countries such as the United States and Canada.
...
The result of promoting a system of biomass electricity from dedicated tree harvesting will in all realistic scenarios mean there will be substantially more carbon in the air for decades, regardless of the type of forest and no matter how sustainably they are managed...

...carbon emissions will rise by 6% or possibly more if wood is allowed to continue to provide more and more of Europe’s energy output"

https://www.theguardian.com/environment/2017/dec/31/biomass-burning-misguided-say-climate-experts