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Ned W

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Re: Global Surface Air Temperatures
« Reply #1600 on: September 18, 2017, 06:03:04 PM »
Just read through the Ned W/Jai discussion and I feel like a Yanomami tribesman from the Amazon rainforest who has just found himself at Wimbledon watching a tennis match without knowing the rules.
Eh.  The level of vitriol in that discussion was unpleasant, and it was off-topic for a thread on "global surface temperatures" anyway.  I started a new thread in the "Science" section of the ASIF, which hopefully will stay more on topic and have fewer insults. 

TerryM

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Re: Global Surface Air Temperatures
« Reply #1601 on: September 19, 2017, 01:04:23 PM »
Just read through the Ned W/Jai discussion and I feel like a Yanomami tribesman from the Amazon rainforest who has just found himself at Wimbledon watching a tennis match without knowing the rules.
Eh.  The level of vitriol in that discussion was unpleasant, and it was off-topic for a thread on "global surface temperatures" anyway.  I started a new thread in the "Science" section of the ASIF, which hopefully will stay more on topic and have fewer insults.


FWIW, I thought you handled the situation(s) admirably. I thoroughly enjoyed the discussion & might even have learned something. ;<}


Best to all
Terry

GeoffBeacon

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Re: Global Surface Air Temperatures
« Reply #1602 on: September 19, 2017, 02:15:59 PM »
I've been looking at Carbon Brief's Guest post: Why the 1.5C warming limit is not yet a geophysical impossibility

It's by Dr Richard Millar who is is a postdoctoral research fellow at the Oxford Martin Net Zero Carbon Investment Initiative.

I'm rather resistant to it's underlying message, which I think is erring on the side of least drama. Has anyone else this feeling?
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Shared Humanity

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Re: Global Surface Air Temperatures
« Reply #1603 on: September 19, 2017, 02:28:14 PM »
Just read through the Ned W/Jai discussion and I feel like a Yanomami tribesman from the Amazon rainforest who has just found himself at Wimbledon watching a tennis match without knowing the rules.
Eh.  The level of vitriol in that discussion was unpleasant, and it was off-topic for a thread on "global surface temperatures" anyway.  I started a new thread in the "Science" section of the ASIF, which hopefully will stay more on topic and have fewer insults.


FWIW, I thought you handled the situation(s) admirably. I thoroughly enjoyed the discussion & might even have learned something. ;<}


Best to all
Terry

My main point was not about the supposed vitriol but the back and forth nature of a discussion that presented information I have no hope of understanding. My second post was intended to highlight what I do understand and that is the relentless and rapidly accelerating warming of the planet. Whether Ned or Jai are more on point and whether I understand their thoughtful, informed points of view seems to have little impact on this simple fact.
« Last Edit: September 19, 2017, 02:51:01 PM by Shared Humanity »

Daniel B.

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Re: Global Surface Air Temperatures
« Reply #1604 on: September 19, 2017, 02:54:47 PM »
I've been looking at Carbon Brief's Guest post: Why the 1.5C warming limit is not yet a geophysical impossibility

It's by Dr Richard Millar who is is a postdoctoral research fellow at the Oxford Martin Net Zero Carbon Investment Initiative.

I'm rather resistant to it's underlying message, which I think is erring on the side of least drama. Has anyone else this feeling?

Not sure that he is erring on any side.  He is appearing to be rather candid, and making his contentions without fanfare or passion.  His claim is that if we can start reducing emissions in earnest by 2020, and fall to near-zero emissions by 2050, that we will maintain warming to below 1.5C.  This is a reasonable plan, that most can live with.

Ned W

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Re: Global Surface Air Temperatures
« Reply #1605 on: September 19, 2017, 04:12:29 PM »
I've been looking at Carbon Brief's Guest post: Why the 1.5C warming limit is not yet a geophysical impossibility

It's by Dr Richard Millar who is is a postdoctoral research fellow at the Oxford Martin Net Zero Carbon Investment Initiative.
The Millar et al. paper is here

I've only skimmed it so far and have not at all begun to really assimilate it.  As I understand it (disclaimer!) it's based on assumptions about the distribution of values for TCR and ECS that ultimately come from the IPCC AR5, which they note is consistent with observations but lower than (some) models:

Quote
Our median estimate climate response (TCR = 1.6 °C, ECS = 2.6 °C) is defined as the median of log-normal distributions consistent with IPCC-AR5 likely bounds on the TCR and ECS (TCR: 1.0–2.5 °C; ECS: 1.5–4.5 °C). From this, the likely above/below values are found from the 33rd and 67th percentiles of the distribution (TCR: 1.3–1.9 °C; ECS: 2.0–3.3 °C). The median TCR of this log-normal distribution is significantly lower than in the IPCC-AR5 ESM ensemble but is more consistent with observed warming to date than many ensemble members (see Supplementary Methods), indicative of the multiple lines of evidence used to derive the IPCC-AR5 uncertainty ranges.
Those values of TCR and ECS are reasonably realistic IMVHO (though others here will vehemently disagree) but I'm still dubious about Millar et al's conclusions regarding avoidance of 1.5 C warming.  I will wait to say more until I've had time to read further.

Shared Humanity

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Re: Global Surface Air Temperatures
« Reply #1606 on: September 19, 2017, 04:14:37 PM »

Not sure that he is erring on any side.  He is appearing to be rather candid, and making his contentions without fanfare or passion.  His claim is that if we can start reducing emissions in earnest by 2020, and fall to near-zero emissions by 2050, that we will maintain warming to below 1.5C.  This is a reasonable plan, that most can live with.

I am in agreement except with the last statement in bold. Most people in the U.S. are still opposed to such a plan.

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1607 on: September 19, 2017, 05:07:45 PM »
I've been looking at Carbon Brief's Guest post: Why the 1.5C warming limit is not yet a geophysical impossibility

It's by Dr Richard Millar who is is a postdoctoral research fellow at the Oxford Martin Net Zero Carbon Investment Initiative.
The Millar et al. paper is here

I've only skimmed it so far and have not at all begun to really assimilate it.  As I understand it (disclaimer!) it's based on assumptions about the distribution of values for TCR and ECS that ultimately come from the IPCC AR5, which they note is consistent with observations but lower than (some) models:

Quote
Our median estimate climate response (TCR = 1.6 °C, ECS = 2.6 °C) is defined as the median of log-normal distributions consistent with IPCC-AR5 likely bounds on the TCR and ECS (TCR: 1.0–2.5 °C; ECS: 1.5–4.5 °C). From this, the likely above/below values are found from the 33rd and 67th percentiles of the distribution (TCR: 1.3–1.9 °C; ECS: 2.0–3.3 °C). The median TCR of this log-normal distribution is significantly lower than in the IPCC-AR5 ESM ensemble but is more consistent with observed warming to date than many ensemble members (see Supplementary Methods), indicative of the multiple lines of evidence used to derive the IPCC-AR5 uncertainty ranges.
Those values of TCR and ECS are reasonably realistic IMVHO (though others here will vehemently disagree) but I'm still dubious about Millar et al's conclusions regarding avoidance of 1.5 C warming.  I will wait to say more until I've had time to read further.

Ned,

You are correct that "... others here will vehemently disagree ..." that using AR5 median values for TCR and ECS is a good idea for calculating the remaining carbon budget, as Proistosescu & Huybers (2017), and others since AR5 was published, have clearly demonstrated that AR5 erred on the side of least drama w.r.t. these values:

Cristian Proistosescu and Peter J. Huybers (05 Jul 2017), "Slow climate mode reconciles historical and model-based estimates of climate sensitivity", Science Advances, Vol. 3, no. 7, e1602821, DOI: 10.1126/sciadv.1602821

http://advances.sciencemag.org/content/3/7/e1602821

Extract: "The latest Intergovernmental Panel on Climate Change Assessment Report widened the equilibrium climate sensitivity (ECS) range from 2° to 4.5°C to an updated range of 1.5° to 4.5°C in order to account for the lack of consensus between estimates based on models and historical observations. The historical ECS estimates range from 1.5° to 3°C and are derived assuming a linear radiative response to warming. A Bayesian methodology applied to 24 models, however, documents curvature in the radiative response to warming from an evolving contribution of interannual to centennial modes of radiative response. Centennial modes display stronger amplifying feedbacks and ultimately contribute 28 to 68% (90% credible interval) of equilibrium warming, yet they comprise only 1 to 7% of current warming. Accounting for these unresolved centennial contributions brings historical records into agreement with model-derived ECS estimates."

See also the linked article entitled: "Why the climate is more sensitive to carbon dioxide than weather records suggest"

https://phys.org/news/2017-07-climate-sensitive-carbon-dioxide-weather.html

Extract: "According to their statistical analysis, historical weather observations reveal only a portion of the planet's full response to rising CO₂ levels. The true climate sensitivity will only become manifest on a time scale of centuries, due to effects that researchers call "slow climate feedbacks".

To understand this, it is important to know precisely what we mean when we talk about climate sensitivity. So-called "equilibrium climate sensitivity", or slow climate feedbacks, refers to the ultimate consequence of climate response – in other words, the final effects and environmental consequences that a given greenhouse gas concentration will deliver.

These can include long-term climate feedback processes such as ice sheet disintegration with consequent changes in Earth's surface reflection (albedo), changes to vegetation patterns, and the release of greenhouse gases such as methane from soils, tundra or ocean sediments. These processes can take place on time scales of centuries or more. As such they can only be predicted using climate models based on prehistoric data and paleoclimate evidence.

On the other hand, when greenhouse gas forcing rises at a rate as high as 2–3 parts per million (ppm) of CO₂ per year, as is the case during the past decade or so, the rate of slow feedback processes may be accelerated.

Measurements of atmosphere and marine changes made since the Industrial Revolution (when humans first began the mass release of greenhouse gases) capture mainly the direct warming effects of CO₂, as well as short-term feedbacks such as changes to water vapour and clouds.
A study led by climatologist James Hansen concluded that climate sensitivity is about 3℃ for a doubling of CO₂ when considering only short-term feedbacks. However, it's potentially as high as 6℃ when considering a final equilibrium involving much of the West and East Antarctic ice melting, if and when global greenhouse levels transcend the 500-700ppm CO₂ range."

Edit: Please note that in the first attached image that the bar for observational ICS values entitled "Marvel et al 2016; Otto et. al. accounting for efficacy" has a median value for ICS of about 3.25C (and an upper value close to 8C); which is close to the median value on the bar entitled "PH17 (w/Lewis Comments)" for the modeled value of ICS.  However, the median value of the modeled ECS value for the bar entitled "PH 17" [Proistosescu & Huybers (2017)] is close to 3.7C (with an upper value close above 6C).  This is all evidence that AR5 errs on the side of least drama.

Edit 2:  The first attached image is from: "Sensible Questions on Climate Sensitivity"

http://www.realclimate.org/index.php/archives/2017/08/sensible-questions-on-climate-sensitivity/
« Last Edit: September 19, 2017, 05:14:43 PM by AbruptSLR »
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jai mitchell

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Re: Global Surface Air Temperatures
« Reply #1608 on: September 19, 2017, 05:54:09 PM »
Glen Peters has a good blog post on this recent paper

http://www.cicero.uio.no/no/posts/nyheter/commentary-did-15c-suddenly-get-easier

Quote
We know that global average temperatures may increase as much as 0.25°C per decade, and that would mean it would take 20 years (two decades) to go from about 1°C today to 1.5°C. Since we emit about 40 billion tonnes CO2 per year, that would give a budget of about 800 billion tonnes of CO2 if we assumed emissions remained constant.

so, their definition of budget is:

Quote
The amount of emissions we can produce before GMST crosses the 1.5C threshold.

which is like saying, "we are moving at 200 Km per hour and cannot possibly stop in time to prevent a collision with a brick wall, but we DO have 170 meters until we crash"  So we have a 'budget' of 170 meters.

Also see his excellent post on the difference between *exceed* and *avoid* CO2 budgets

http://www.cicero.uio.no/no/posts/klima/should-climate-policy-aim-to-avoid-2c-or-to-exceed-2c

Note (of all people) posted this:  https://twitter.com/RichardTol/status/910125828410888192

Quote
A carbon budget should be a function of cumulative emissions and climate sensitivity, not of the actual temperature.

(perhaps I should repost in "Conservative Scientists and its Consequences" thread. . .  >:( )

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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1609 on: September 21, 2017, 05:01:40 PM »
The linked article emphasizes that CMIP5 projections have not 'exaggerated' global warming:

Title: "Factcheck: Climate models have not ‘exaggerated’ global warming"

https://www.carbonbrief.org/factcheck-climate-models-have-not-exaggerated-global-warming

Extract: "The results of model/observation comparisons differ greatly based on the dataset used, the model outputs analysed – model air temperatures or blended model air/ocean temperatures – and the time period examined. While the Millar et al study points out some sizable differences between the HadCRUT record and the model air temperature field, this should not be generalised to conclude that warming projections are unreliable or that warming has been ‘exaggerated by faulty models’. The paper’s real focus is on carbon budgets and carbon cycle accuracy, rather than model/observation comparisons of the warming associated with increased atmospheric greenhouse gas concentrations, and their results have little bearing on our understanding of climate sensitivity."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Ned W

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Re: Global Surface Air Temperatures
« Reply #1610 on: September 21, 2017, 06:43:27 PM »
Ed Hawkins (Climate Lab Book) also has a new post addressing this model/data comparison problem, based on Medhaug et al. 2017

Are the models “running too hot”?

Short answer: No, the models are not "running too hot".

I actually hate the graph included in that post (it's from Medhaug 2017) which IMHO would likely confuse the casual reader more than necessary.  The key point is the similarity between the darkest orange thin line (Estimated GMST) and the dark blue thin line (CMIP5 GMST with forcing and variability). 


AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1611 on: September 21, 2017, 10:29:04 PM »
I note that Hawkins et al (2017) defines the pre-industrial baseline to be from 1720-1800 for determining GMSTA, and indicates that as the AR5 projections are baselined to the 1896-2005 baseline, one needs to add about 0.6C to the AR5 GMSTA projections to reference them to the pre-industrial baseline.  I note that means that climate sensitivity is slightly higher than previously thought (when using 1850-1900 observations as a baseline).

Hawkins, E., P. Ortega, E. Suckling, A. Schurer, G. Hegerl, P. Jones, M. Joshi, T. Osborn, V. Masson-Delmotte, J. Mignot, P. Thorne, and G. van Oldenborgh (2017), "Estimating changes in global temperature since the pre-industrial period", Bull. Amer. Meteor. Soc. doi:10.1175/BAMS-D-16-0007.1

http://journals.ametsoc.org/doi/10.1175/BAMS-D-16-0007.1
http://journals.ametsoc.org/doi/pdf/10.1175/BAMS-D-16-0007.1

Abstract: "Better defining (or altogether avoiding) the term ‘pre-industrial’ would aid interpretation of internationally agreed global temperature limits and estimation of the required constraints to avoid reaching those limits.
The United Nations Framework Convention on Climate Change (UNFCCC) process agreed in Paris to limit global surface temperature rise to ‘well below 2°C above pre-industrial levels’. But what period is ‘pre-industrial’? Some-what remarkably, this is not defined within the UNFCCC’s many agreements and protocols. Nor is it defined in the IPCC’s Fifth Assessment Report (AR5) in the evaluation of when particular temperature levels might be reached because no robust definition of the period exists. Here we discuss the important factors to consider when defining a pre-industrial period, based on estimates of historical radiative forcings and the availability of climate observations. There is no perfect period, but we suggest that 1720-1800 is the most suitable choice when discussing global temperature limits. We then estimate the change in global average temperature since pre-industrial using a range of approaches based on observations, radiative forcings, global climate model simulations and proxy evidence. Our assessment is that this pre-industrial period was likely 0.55–0.80°C cooler than 1986-2005 and that 2015 was likely the first year in which global average temperature was more than 1°C above pre-industrial levels. We provide some recommendations for how this assessment might be improved in future and suggest that reframing temperature limits with a modern baseline would be inherently less uncertain and more policy-relevant."
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1612 on: September 24, 2017, 03:14:54 AM »
Per the linked websites, August 2017 GISTEMP was the second warmest August in 137 years of modern record-keeping:

https://www.skepticalscience.com/2017-SkS-Weekly-News-Roundup_38.html

&

https://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1613 on: October 06, 2017, 04:55:25 PM »
The linked article notes how relatively well current climate models match current observations (see attached table); however, I warn that as GMSTA approaches/exceeds 2C model projections become increasingly nonlinear and the best models indicate that climate sensitivity increases with increasing GMSTA:

Title: "Analysis: How well have climate models projected global warming?"

https://www.carbonbrief.org/analysis-how-well-have-climate-models-projected-global-warming

Extract: "Climate models published since 1973 have generally been quite skillful in projecting future warming. While some were too low and some too high, they all show outcomes reasonably close to what has actually occurred, especially when discrepancies between predicted and actual CO2 concentrations and other climate forcings are taken into account.

Models are far from perfect and will continue to be improved over time. They also show a fairly large range of future warming that cannot easily be narrowed using just the changes in climate that we have observed."
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Sigmetnow

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Re: Global Surface Air Temperatures
« Reply #1614 on: October 08, 2017, 04:54:53 PM »
Limited to Arctic air temps in the satellite era, but shows the trend beautifully.
(Also posted in 2017 Melting Season.)

Quote
Monthly Arctic air temperature (925hPa) rankings over the satellite era (from 1979)

Additional temperature graphics  http://sites.uci.edu/zlabe/arctic-temperatures/
https://twitter.com/ZLabe/status/915964532282974208
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1615 on: October 17, 2017, 06:04:57 PM »
The GISS LOTI value of 80 was recently posted for September 2017.  This give a GMSTA above pre-industrial of 1.15C for a 12-month running GISS LOTI assuming the following conversion (To convert 1951-1980 temp departures to pre-industrial add: + 0.256 Celsius).  This is not good news considering that the ENSO condition is currently on the cold side of neutral.
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rboyd

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Re: Global Surface Air Temperatures
« Reply #1616 on: October 18, 2017, 03:19:22 AM »
If this is anywhere near accurate, then October is not looking good GMST (the black line) wise. The northern hemisphere is looking particularly warm.

http://www.karstenhaustein.com/climate.php
« Last Edit: October 18, 2017, 03:28:11 AM by rboyd »

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1617 on: October 23, 2017, 04:52:50 PM »
Per the linked article, the U.S. is warming faster than is GMSTA:

Title: "2017 on Track to Be Third Hottest Year Nationally"

http://www.climatecentral.org/gallery/graphics/2017-on-track-to-be-third-hottest-year-nationally

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Wipneus

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Re: Global Surface Air Temperatures
« Reply #1618 on: October 28, 2017, 12:08:12 PM »
Its a while since I updated my Hadcrut graph with projected 2017 temperature.

Hadcrut had a version bump from 4.5 to 4.6. Most changes have to do with more stations, covering a bigger percentage of the earth. The most important consequence appears to be that 2016 is now clearly the hottest year, like most other GST calculations.

Latest update includes September. The projected annual 2017 temperature will very likely be third warmest also in the HadCrut calculation.

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1619 on: November 02, 2017, 02:20:55 PM »
Scribbler correctly points-out that polar amplification is starting to ramp-up:

Title: "Predicted Record 94 Degree (F) November Temperatures for Dallas as Globe Warms Despite Trend Toward La Nina"

https://robertscribbler.com/2017/11/01/predicted-94-degree-f-november-temperatures-for-dallas-as-globe-warms-despite-trend-toward-la-nina/

Extract: "So despite a weak La Nina forming, it again appears that polar warming is a major driver for global temperatures as fall moves into winter. Climatologists take note."
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jai mitchell

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Re: Global Surface Air Temperatures
« Reply #1620 on: November 02, 2017, 04:36:58 PM »
 ???
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Shared Humanity

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Re: Global Surface Air Temperatures
« Reply #1621 on: November 02, 2017, 04:49:06 PM »
There is clearly something that happened here. When did the Beaufort begin to become seasonally ice free?

TerryM

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Re: Global Surface Air Temperatures
« Reply #1622 on: November 02, 2017, 08:42:24 PM »
Clearly not a baby step. Is November next, or will the long winter night preclude this possibility?
Terry

Shared Humanity

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Re: Global Surface Air Temperatures
« Reply #1623 on: November 02, 2017, 08:48:49 PM »
Can we see similar "October Effects" in other peripheral seas in the basin that are increasingly ice free at the end of the melt season? Where are temperatures recorded in Chukchi, ESS, Laptev?

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1624 on: November 03, 2017, 04:48:47 PM »
Per the following data and the attached image, the NCEP/NCAR GMSTA for Oct 2017 was 0.372C; which was the highest monthly anomaly since May:

Last 12 months averages
See below for GISS,NOAA

Year   Month Anomaly
2017   Oct   0.372
2017   Sep   0.317
2017   Aug   0.337
2017   Jul   0.299
2017   Jun   0.241
2017   May   0.4
2017   Apr   0.34

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Niall Dollard

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Re: Global Surface Air Temperatures
« Reply #1625 on: November 04, 2017, 03:53:41 PM »
Copernicus October 2017 global surface temp data is now available. October 2017 extended the spell of exceptional global warmth that has now lasted since mid-2015. It was :

   - close to 0.6°C warmer than the average October from 1981-2010;

   - the second warmest October on record, though only by a very small margin of 0.01°C over October 2016;

   - about 0.06°C cooler than the warmest October, which occurred in 2015.

Interiors of Africa and Asia show cool anomalies, but warmth predominates. Greenland and Svalbard look like a red rash.
   

Niall Dollard

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Re: Global Surface Air Temperatures
« Reply #1626 on: November 04, 2017, 04:16:16 PM »
Replying here to Jai Mitchell's graph posted earlier in this thread (although I know this is the global temperature thread), Berkeley Earth indicate that there have been significant siting changes at Barrow (As is a common occurrence at airport sites)

Estimated station mean bias is running about +0.6 C above the regional average. More recent data is showing +1.0 C !

Berkeley show no fewer than seven "station moves" since 1999. In the previous 50 years there were no station moves.

With such poor site continuity, it will be very difficult to determine the true temperature change at Barrow this century. 
« Last Edit: November 04, 2017, 04:33:51 PM by Niall Dollard »

AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1627 on: November 05, 2017, 06:50:43 PM »
While the data is limited, the linked RealClimate article makes me suspect that the ENSO cycle and Arctic Amplification are now working synergistically to increase climate sensitivity:

Title: "El Niño and the record years 1998 and 2016"

http://www.realclimate.org/index.php/archives/2017/11/el-nino-and-the-record-years-1998-and-2016/#more-20806

Extract: "2017 is set to be one of warmest years on record. Gavin has been making regular forecasts of where 2017 will end up, and it is now set to be #2 or #3 in the list of hottest years."
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1628 on: November 09, 2017, 07:04:34 PM »
Per the attached table Berkeley Earth gives 2017 a 85% chance of being the second warmest year on record:

Title: "State of the climate: 2017 shaping up to be warmest ‘non-El Niño’ year"

https://www.carbonbrief.org/state-of-the-climate-2017-shaping-up-to-be-warmest-non-el-nino-year
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Lord M Vader

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Re: Global Surface Air Temperatures
« Reply #1629 on: November 11, 2017, 07:21:00 PM »
Dear fellow forum friends, if you have't read this srticle, I strongly urge you to do that!

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0741.1

As it is a paywall article, a summary of it is available at

https://news.upenn.edu/news/penn-how-openings-antarctic-sea-ice-affect-worldwide-climate

and

http://earthsky.org/earth/openings-in-antarctic-sea-ice-influence-global-climate

Best, LMV

jai mitchell

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Re: Global Surface Air Temperatures
« Reply #1630 on: November 11, 2017, 11:29:51 PM »
Replying here to Jai Mitchell's graph posted earlier in this thread

Thanks Niall, I expected that was the case but did not have the info to back it up.
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1631 on: November 16, 2017, 06:21:05 PM »
NASA has just released the GISTEMP LOTI for October 2017 to be 90, and per my calculations (assuming a correction factor to a pre-industrial baseline of 0.256C) this gives a 12-month running average GMSTA of about: +1.159C.

See the linked GISTEMP LOTI website:

http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
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Lord M Vader

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Re: Global Surface Air Temperatures
« Reply #1632 on: November 19, 2017, 04:13:03 PM »
While it's just a daily value, Nick Stokes just reported a negative anomaly(!). Last time that happened must have been in early 2015 or 2014.... Any one who remember the last time when the daily anomaly was negative?

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Re: Global Surface Air Temperatures
« Reply #1633 on: November 21, 2017, 03:38:06 AM »
Indulge Your Existential Dread 24/7 With This Real-Time Global Warming Clock
Quote
If there is one lesson of 2017, it’s that we are all going to die. But while nobody can predict when the bombs will drop or when billionaires will siphon your young blood, the Debbie Downers at Oxford did build a real time global warming index that lets you watch as we creep closer and closer to planetary heat death.

Gaze upon it and let the familiar wave anxiety wash over you. Go ahead, indulge those dark feelings. Click the link. I’ll wait.

http://www.globalwarmingindex.org

What you see is a global warming index based on research published last week in Scientific Reports. It includes an up-to-the-second estimate of how much warmer we’ve made the planet since the mid-1800s.

The scientists at Oxford and other institutions were able to estimate that by breaking out the natural fluctuations in climate that we know about—El Niño, volcanic eruptions, obscure climate oscillations—from the unnatural one we’re causing through our ever-increasing carbon emissions.

The findings are bleak AF. Humans have caused all of the observed warming since the 1850s according to the new study. Natural climate shifts contributed a whopping minus 0.01 degrees Celsius (minus 0.018 degrees Fahrenheit) give or take a few hundredths of a degree of change. We’re boiling ourselves slowly, like a frog in a pot.

Every second that passes brings us closer to the 2 degree Celsius threshold outlined as a “safe” amount of warming that humanity can handle. Every speck of carbon we chuck in the atmosphere puts one step closer to plunging off a planetary cliff. ...
https://earther.com/indulge-your-existential-dread-24-7-with-this-real-time-1820618735/
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gerontocrat

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Re: Global Surface Air Temperatures
« Reply #1634 on: November 21, 2017, 03:48:07 PM »
In the Southern Hemisphere SST anomalies are just 0.01 degrees centigrade positive. There is very cold water along the pacific equator and down the coast of South America.
At the same time it is November 21st, meaning we are in peak insolation for the Southern hemisphere for a few months.

Does this mean the oceans will be gobbling up more heat than when SST anomalies  are +ve  (temperature gradient higher) ? if so, beware the next el nino?
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1635 on: November 21, 2017, 05:17:09 PM »
Indulge Your Existential Dread 24/7 With This Real-Time Global Warming Clock

For a more complete reference, I provide the following, without comment:

K. Haustein et al. (2017), "A real-time Global Warming Index", Scientific Reports 7, DOI:10.1038/s41598-017-14828-5

https://www.nature.com/articles/s41598-017-14828-5.pdf

Introduction: "2016 was the third year in a row with a record-setting global mean surface temperature (GMST), inviting the question of how much of this burst of recent warming is due to human activities, and how much to natural variability, just as the purported “lack of warming” has been scrutinized before 2014 for the opposite reason. This issue matters for policy, given the decision made in UN negotiations to structure international aims around global temperature targets; and it matters even more in view of the proximity of the lower of the two figures mentioned in the 2015 Paris Agreement which has the stated aims of “Holding the increase in the global average temperature to well below 2 °C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 °C above pre-industrial levels”. While scientists are familiar with the role of natural variability in GMST, now and on future trajectories, policymakers have not (to date) accounted for natural variability in UNFCCC negotiating texts. The phrase “global average temperature” could be given several reasonable interpretations, including annual observed GMST as determined by a single data series; annual observed GMST as determined by several data series; multi-year running means; or, as we argue here, assessments of the anthropogenic component of the observed warming.

Otto et al. proposed an index of human-induced warming based on a simple least-squares fit between observed temperatures and the expected responses to anthropogenic and natural radiative forcing. However, they did not provide a thorough assessment of its robustness, its sensitivity to internal variability, or its uncertainty in natural or anthropogenic forcings. They primarily focused on illustrating the utility of such a concept in adaptive mitigation. Here we present a coherent uncertainty analysis for a real-time version of the proposed
warming index that satisfies the need for immediate availability. We update it using monthly GMST and revised monthly radiative forcing data. These timely updates are important should an explosive volcanic eruption occur which will lower GMST almost instantly. As a reference period we use 1850–79, which represents the earliest 30 year period in most observational records. Since some volcanic activity is recorded in the 1850s, we also test the 1861–1880 period. Years after 1880 are affected by the very negative Krakatoa forcing. Use of earlier reference
periods would be closer to “pre-industrial”, but that is not possible due to the absence of global instrumental data. The IPCC has often used 1851–1900 as pre-industrial reference period, prompting us to repeat the analysis one more time with this interval.

Whether or not fluctuations in GMST (such as the so-called “hiatus”) and the scientific response thereto have contributed to slow down progress of climate negotiations is a moot point. Now that we have, through the Paris Agreement, an explicit global temperature goal, we believe it is all the more necessary to have an easily accessible and understandable index of total anthropogenic warming, designed to reduce effects of internal and naturally-driven climate variability."

For the real time index see:

http://www.globalwarmingindex.org/

See also:

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

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Re: Global Surface Air Temperatures
« Reply #1636 on: November 27, 2017, 03:48:44 AM »
I've got a question about global temperatures. As I recall an El Nino event shows a much more pronounced effect in the satellite data than in the surface data sets. This can clearly be seen in the 97/98 and 2009/2010 El Nino's. However, when you look at the 2015/2016 El Nino the satellite data response is about the same as the surface data. Does anyone have an explanation for this?

« Last Edit: November 27, 2017, 09:40:48 AM by Krakatoa »

Niall Dollard

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Re: Global Surface Air Temperatures
« Reply #1637 on: November 27, 2017, 11:03:32 PM »
However, when you look at the 2015/2016 El Nino the satellite data response is about the same as the surface data. Does anyone have an explanation for this?

The satellite and surface data response is not the same in 2015/16. It has been made look the same on "woodfortrees" graph through the application of offsets.

e.g. the gistemp data has an offset of -0.423889. The gistemp red line graph appears to show an "anomaly" of just over 0.6, which as you say is the same anomaly as the UAH satellite data (purple line).

But the UAH line has no offset applied and if you add on the offset to the gistemp line it would make the anomaly for 2015/2016 much higher (over 1.0).

It maybe not all that apparent on the woodfortrees graph is that the global satellite, global land only and global land/ocean graphs are all increasing at different rates but all do show particular increases during el nino events.

They are increasing at different rates because of different environments.

Both satellite data and surface data show big difference between ocean and land. The temperature trends in these two contrasting environments are quite different. Trend line gradients show the global land warming by over twice as much as the global oceans. Same goes when you split up the UAH data into land and ocean.   

There is an interesting comparative analysis on this page. But warning, the author does extol the virtues of the satellite derived method and many do have reservations about that method.

http://euanmearns.com/surface-versus-satellite-the-temperature-data-set-controversy/

The satellite data is prone to systematic error as time progresses and consequently there have been many revisions since 1979. This real climate article highlights problems associated with satellite data:

http://www.realclimate.org/index.php/archives/2017/03/the-true-meaning-of-numbers/comment-page-3/

Krakatoa

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Re: Global Surface Air Temperatures
« Reply #1638 on: November 27, 2017, 11:37:40 PM »
However, when you look at the 2015/2016 El Nino the satellite data response is about the same as the surface data. Does anyone have an explanation for this?

The satellite and surface data response is not the same in 2015/16. It has been made look the same on "woodfortrees" graph through the application of offsets.

e.g. the gistemp data has an offset of -0.423889. The gistemp red line graph appears to show an "anomaly" of just over 0.6, which as you say is the same anomaly as the UAH satellite data (purple line).

But the UAH line has no offset applied and if you add on the offset to the gistemp line it would make the anomaly for 2015/2016 much higher (over 1.0).



Those offsets are done to give all data sets the same baseline (1981-2010). The 2015-2016 El Nino shows a bit more warming in the satellite data, but it's nowhere near the difference in response the 1997-1998 El Nino had.

Niall Dollard

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Re: Global Surface Air Temperatures
« Reply #1639 on: November 28, 2017, 12:07:26 AM »
Yes I agree, difference is nowhere near as big compared to 1998. (thanks for clarifying the offsets).

Does this mean the satellite data is coming more in line with the surface data ? Or visa versa ?

I see October 2017 was the 7th warmest month ever in the UAH series (anomaly of +0.63 C).

What is the gistemp anomaly (w.r.t 1981-2010) for October 2017?

NASA/gistemp give an anomaly of +0.9 C- but that is using baseline of 1951-1980. Does the woodfortrees offset of -0.4233889 work to bring it in line with 1981-2010 ?

If so then gistemp anomaly is 0.48 C.  I am surprised it is lower than the satellite data.

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Re: Global Surface Air Temperatures
« Reply #1640 on: November 28, 2017, 12:18:11 AM »

I know the last week is a forecast, but those are some crazy NH temperatures (they will have to move their legend if it comes true).

http://www.karstenhaustein.com/climate.php


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Re: Global Surface Air Temperatures
« Reply #1641 on: November 28, 2017, 09:10:17 AM »
I've got a question about global temperatures. As I recall an El Nino event shows a much more pronounced effect in the satellite data than in the surface data sets. This can clearly be seen in the 97/98 and 2009/2010 El Nino's. However, when you look at the 2015/2016 El Nino the satellite data response is about the same as the surface data. Does anyone have an explanation for this?

Have Christy and Spencer shared all the data and processes that go into the UAH product? I haven't followed that stuff for a while now, but maybe that's where the answer is. I wouldn't put it past those guys to try to make the elephant wiggle his trunk.
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Krakatoa

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Re: Global Surface Air Temperatures
« Reply #1642 on: November 28, 2017, 12:15:44 PM »
Yes I agree, difference is nowhere near as big compared to 1998. (thanks for clarifying the offsets).

Does this mean the satellite data is coming more in line with the surface data ? Or visa versa ?

I see October 2017 was the 7th warmest month ever in the UAH series (anomaly of +0.63 C).

What is the gistemp anomaly (w.r.t 1981-2010) for October 2017?

NASA/gistemp give an anomaly of +0.9 C- but that is using baseline of 1951-1980. Does the woodfortrees offset of -0.4233889 work to bring it in line with 1981-2010 ?

If so then gistemp anomaly is 0.48 C.  I am surprised it is lower than the satellite data.

Yeah, that is the right offset. I calculated those by putting the 30 year averages to 0 at 1996. I guess that's the right method.
The satellite data have shown a remarkable uptick the last couple of months and are now indeed higher than the surface data.

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Re: Global Surface Air Temperatures
« Reply #1643 on: November 28, 2017, 12:35:49 PM »
I've got a question about global temperatures. As I recall an El Nino event shows a much more pronounced effect in the satellite data than in the surface data sets. This can clearly be seen in the 97/98 and 2009/2010 El Nino's. However, when you look at the 2015/2016 El Nino the satellite data response is about the same as the surface data. Does anyone have an explanation for this?

Have Christy and Spencer shared all the data and processes that go into the UAH product? I haven't followed that stuff for a while now, but maybe that's where the answer is. I wouldn't put it past those guys to try to make the elephant wiggle his trunk.

RSS shows the same, so it's not Spencer and Christy's doing.

But it's funny how RSS and UAH go in opposite directions after their latest revisions. UAH used to be more in line with the surface data, but now with v6.0 it shows much less warming. While RSS used to be the odd one out, but is now the one most in line with the surface data.
In the back of my head there is the suspicion that Spencer and Christy did their best to find an algorithm that show the least warming, but I don't want to go that route. I think the most important point is that the satellite data sets agree way less with each other than the different surface sets and therefore are less reliable.

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Re: Global Surface Air Temperatures
« Reply #1644 on: November 28, 2017, 01:05:21 PM »

RSS shows the same, so it's not Spencer and Christy's doing.

But it's funny how RSS and UAH go in opposite directions after their latest revisions. UAH used to be more in line with the surface data, but now with v6.0 it shows much less warming. While RSS used to be the odd one out, but is now the one most in line with the surface data.
In the back of my head there is the suspicion that Spencer and Christy did their best to find an algorithm that show the least warming, but I don't want to go that route. I think the most important point is that the satellite data sets agree way less with each other than the different surface sets and therefore are less reliable.

Yes agree with that. To back it up:





https://www.carbonbrief.org/major-correction-to-satellite-data-shows-140-faster-warming-since-1998

>RSS shows the same, so it's not Spencer and Christy's doing.
While RSS does show it to some extent, perhaps theirs looks pretty well 'reasonable' when compared to UAH v6 which looks surprising in this El Nino exaggerated effect expectation?


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Re: Global Surface Air Temperatures
« Reply #1645 on: November 28, 2017, 06:00:38 PM »

RSS shows the same, so it's not Spencer and Christy's doing.

But it's funny how RSS and UAH go in opposite directions after their latest revisions. UAH used to be more in line with the surface data, but now with v6.0 it shows much less warming. While RSS used to be the odd one out, but is now the one most in line with the surface data.
In the back of my head there is the suspicion that Spencer and Christy did their best to find an algorithm that show the least warming, but I don't want to go that route. I think the most important point is that the satellite data sets agree way less with each other than the different surface sets and therefore are less reliable.

Yes agree with that. To back it up:

As averaged over fluctuations about 90% of global warming heat ends up in the oceans, and as per the attached image, from the following linked source, indicates the ocean absorbed a lot of heat during the 1997-98 Super El Nino; I suspect that the ocean absorbed less heat during the 2015-16 event; which (if true) would leave more heat in the atmosphere near the ground surface (maybe jai has a link to ocean heat content during the 2015-16 Super El Nino event, as I am distracted):

https://www.ocean-sci.net/12/925/2016/os-12-925-2016.pdf
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Niall Dollard

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Re: Global Surface Air Temperatures
« Reply #1646 on: November 28, 2017, 06:38:42 PM »
Here are the GISS Loti and UAH v6 anomalies so far this year (wrt 1981-2010 )

Since June, UAH anomalies are on continuous rise. GISS peaked early in the year. There is a considerable contrast between March and Oct.

On the other hand May and June anomalies were quite close (within 0.1).

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Re: Global Surface Air Temperatures
« Reply #1647 on: November 28, 2017, 06:44:49 PM »
(maybe jai has a link to ocean heat content during the 2015-16 Super El Nino event, as I am distracted):

While I do not have time to analyze it properly, it looks to me like the OHC data for water depths from 0 to 700m through Sept 2017, from the following NOAA site, indicates that the ocean likely absorbed less heat during the 2015-16, than during the 1997-98 Super El Nino, event.

https://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/
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jai mitchell

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Re: Global Surface Air Temperatures
« Reply #1648 on: November 28, 2017, 07:41:02 PM »
unfortunately, coverage of 0-700 depth ocean heat content methodologies changed significantly after the deployment of the ARGO float network.  the 0-700 difference in global coverage is inconclusive.  quarterly differentials in ocean heat content including 1 year before and after event are shown.
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AbruptSLR

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Re: Global Surface Air Temperatures
« Reply #1649 on: November 28, 2017, 08:38:41 PM »
unfortunately, coverage of 0-700 depth ocean heat content methodologies changed significantly after the deployment of the ARGO float network.  the 0-700 difference in global coverage is inconclusive.  quarterly differentials in ocean heat content including 1 year before and after event are shown.

jai,

Thanks for the great plot; which indicates to me that at the peak of the 97/98 event the ocean was absorbing unusually high amounts of heat, but during the peak of the 15/16 event the ocean was emitting heat into the atmosphere (I assume by increased evaporation).  This helps to illustrate that the ENSO is an example of a chaotic strange/climate attractor.
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