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Messages - jai mitchell

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1
Doctor Jennifer Francis provides a discussion of the intense Arctic amplification and water vapor anomalies that occurred this year as a result of the record El Nino of 2016.

Every indication is that this pattern will become the 'new abnormal' as a result of global warming and, especially, as a result of reductions in SO2 emissions from SE Asia.

10 minute Francis Presentation here:

full presentation (54 minutes) from three scientists on the subject: 

2
Article today that discusses the implication of wise et al. described above by ASLR and the previous DeConto paper describing Thwaites and PIG SLR potentials.

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

Rapid collapse of Antarctic glaciers could flood coastal cities by the end of this century.

By Eric Holthaus   on Nov 21, 2017

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.

3
Consequences / Re: Conservative Scientists & its Consequences
« on: November 12, 2017, 11:33:21 PM »
I would also expect that the PIG collapse during the early Holocene was also caused by rapid SLR due to freshwater pulses.  Thank you for your in depth response. 

4
Consequences / Re: Conservative Scientists & its Consequences
« on: November 12, 2017, 12:26:04 PM »
I note that this effect could also be responsible for the presence of hippos in England during the last interglacial maximum.  http://www.sciencedirect.com/science/article/pii/S0016787809000054

However, it is unclear (to me) how much of this is driven by WAIS impact (since WAIS was intact at last holocene maximum) and how much is an effect of arctic melt and higher latitude (north) solar insolation.

5
Consequences / Re: Global Surface Air Temperatures
« 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.

6
Consequences / Re: General Drought Stuff
« on: November 11, 2017, 03:22:51 PM »
http://iopscience.iop.org/article/10.1088/1748-9326/aa8fde/meta

Abstract
Washington State experienced widespread drought in 2015 and the largest burned area in the observational record, attributable in part to exceptionally low winter snow accumulation and high summer temperatures. We examine 2015 drought severity in the Cascade and Olympic mountains relative to the historical climatology (1950–present) and future climate projections (mid-21st century) for a mid-range global greenhouse gas emissions scenario. Although winter precipitation was near normal, the regional winter temperature anomaly was +2.1 °C (+2.0σ) in 2015, consistent with projections of a +2.3 °C (+2.2σ) temperature change and near normal precipitation in the future, relative to the climatology. April 1 snow water equivalent in 2015, −325 mm (−1.5σ), and the future, −252 mm (−1.1σ), were substantially lower than the climatology. Wildfire potential, as indicated by dead fuel moisture content, was higher in 2015 than mid-21st century mean projections. In contrast to most historical droughts, which have been driven by precipitation deficits, our results suggest that 2015 is a useful analog of typical conditions in the Pacific Northwest by the mid-21st century.


7
Consequences / Re: General Drought Stuff
« on: November 11, 2017, 03:01:06 PM »
https://www.newsdeeply.com/water/community/2017/05/24/study-western-u-s-snowpack-could-deacline-60-percent-by-2040

Study: Western U.S. Snowpack Could Decline 60 Percent by 2040

The lead author of the new study says a 30 percent decline in mountain snowpack is “very likely” and greater losses are possible. The report points the finger at human-induced changes in the climate.

It was a set of simulations that took several years to complete. And it’s that new set of simulations that allowed us to make what is the most notable statement in this paper, and that is that we’re predicting up to a 60 percent decline in snowpack over the Western U.S. That’s a combination of 30 percent from human impact, and possibly an additional 30 percent decline due to this natural variability. That’s the key result. It is a big number. It’s frightening.

8
Arctic sea ice / Re: PIOMAS vs CryoSat
« on: November 06, 2017, 03:51:06 PM »
Univ of Calgary study indicates that Cryosat-2 has overestimated Freeboard depth due to salinity/reflectivity of first-year sea ice.  First year overestimate of volume up to 25% with total impact on basin (April Max) of 17% overestimated.

link here:  https://www.ucalgary.ca/utoday/issue/2017-10-24/arctic-sea-ice-may-be-thinning-faster-scientists-initially-predicted#.WgBdozOXxfA.twitter

“It has been assumed by the scientific community that CryoSat-2 can accurately measure the sea ice freeboard, which is the ice we can see above sea level,” says Nandan. “But that ice is covered in snow and the snow is salty close to where the sea ice surface is. The problem is, microwave measurements from satellites don’t penetrate the salty snow very well, so the satellite is not measuring the proper sea ice freeboard and the satellite readings overestimate the thickness of the ice.”

9
Arctic sea ice / Re: Latest PIOMAS update (November update)
« on: November 06, 2017, 03:47:59 PM »
Univ of Calgary Study indicates that Cryosat-2 has overestimated thickiness of first-year sea ice by as much as 25% due to salinity content of upper layers.

Overall this bias of extra thckness indicates an overestimate of up to 17 percent of total volume in recent years.

https://www.ucalgary.ca/utoday/issue/2017-10-24/arctic-sea-ice-may-be-thinning-faster-scientists-initially-predicted#.WgBdozOXxfA.twitter

“It has been assumed by the scientific community that CryoSat-2 can accurately measure the sea ice freeboard, which is the ice we can see above sea level,” says Nandan. “But that ice is covered in snow and the snow is salty close to where the sea ice surface is. The problem is, microwave measurements from satellites don’t penetrate the salty snow very well, so the satellite is not measuring the proper sea ice freeboard and the satellite readings overestimate the thickness of the ice.”

10
Science / Re: Carbon Cycle
« on: November 05, 2017, 06:44:15 PM »
This study appears to be limited to the United States.  Since the majority of the worlds forests are located in Canada and Siberia I wonder what the projection of total global forest impacts would be.

11
The rest / Re: The problem of Corporate Democrats and how to kick them out
« on: November 03, 2017, 03:19:28 PM »

So all this money did not matter in the end. So why are we even talking about this ?

man, this information must really hurt you.

Ok, how about this.

The reason that the DNC was bankrupt was because Obama and Debbie Wasserman Schultz kept their high-payed consultant and lobbyist friends on the payroll during non-election cycle years. (its in the article)

They intentionally bankrupted the DNC and the following is why.

They agreed after the 2008 election that after Obama was term limited that Hillary would be the nominee.

They then signed an agreement that gave complete control of all spending, fundraising, staffing and communications to the the Hillary Clinton Campaign in August 2015, fully 6 months before the first state primary.

The result of their agreement was that they put the DNC on a starvation diet, with monthly stipends, funneled 99.5% of state-level funding to their organization and produced the most biased, unfair and corrupt primary election in this nation's history.

The result of these total actions produced such an obvious mistaste of the candidate in the mouths of the 40 and under electorate, as well as the well documented distrust from the traditional DNC base of organized labor members, that she lost an election that ANY democratic party presidential candidate in the HISTORY of presidential candidates would have won.

We could have had a president Bernie Sanders and he would have pushed the climate emergency to the forefront, with the U.S. leading the entire world into a rapid mobilization to get off of fossil fuels and restore a safe, late Holocene climate.

In the end, the delay in emissions reductions that have resulted from the DNC corruption of the power elites, as well as their secondary impacts on state-level races (a TOTAL washout - giving the Senate to the Republicans - which also gave them 6 votes on the Supreme Court) may have ACTUALLY DOOMED humanity to >4C of globally averaged warming.

THAT is why we are talking about this.

12
Policy and solutions / Re: Renewable Energy
« on: November 02, 2017, 04:41:00 PM »
Lazard just released their 2017 levelized cost of energy study

full report here: https://www.lazard.com/media/450337/lazard-levelized-cost-of-energy-version-110.pdf

13
Consequences / Re: Global Surface Air Temperatures
« on: November 02, 2017, 04:36:58 PM »
 ???

14
The rest / Mark Jacobson Lawsuit
« on: November 02, 2017, 01:35:56 PM »
Background here:  https://www.technologyreview.com/the-download/609308/a-renewable-energy-champion-is-suing-his-scientific-critics/

Mark Jacobson of Stanford is relatively famous in the climate mitigation world for developing a national, state by state and (is working on) a global energy resource analysis that shows that is is 'possible' for a state, country or even the whole world to switch all energy consumption to non-fossil fuel (and nuclear) sources. 

Last year the National Academy of Sciences published a response paper co-written by 20 authors to take apart his work.  He claimed that their assertions in the paper (peer reviewed) were intentionally misleading and akin to libel.  It looks like he REALLY believed what he was saying.

Some climate scientists have stated that this is not the correct way to treat scientific debate.  That the conversation should be done through the peer reviewed, refereed literature.  Mark Jacobson did this with a very lengthy response to the paper, which was published.

He is suing for $10 million dollars.

My thoughts,

First off, I am not a big fan of scientists suing people, except when the targets of these lawsuits are actively working, either through ideological insanity or for simple monetary gain, to intentionally suppress good work that is going to help us to get off of fossil fuels and preserve some kind of non-dystopian future for our children.

However, some interesting things about the authors that wrote the paper.

Did there really need to be 20 authors for a response paper?  There is no real core datasets that required field research, why so many authors except to make the paper seem more authoritative.  This is akin to saying, "I win because me and my friends are louder than you are".

Which lends itself to Mark Jacobson's argument that they are intentionally trying to discredit his work, not discuss the scientific merit of his work.

Secondly, Mark Jacobson asserts that most of the 20 authors have ties to Nuclear industry, nuclear support organizations, fossil fuel interests (I think) and/or geoengineering.  He implies that they are trying to suppress his work intentionally to protect their own interests.

In any event this could get interesting.

Mark Jacobson's Paper from 2015:  http://www.pnas.org/content/112/49/15060.full.pdf

Christopher Clack (and 20 authors) paper: http://www.pnas.org/content/114/26/6722.full

Mark Jacobson's Reply: http://www.pnas.org/content/114/26/E5021 

15
Consequences / Re: Hansen et al paper: 3+ meters SLR by 2100
« on: October 26, 2017, 05:56:43 PM »
Evidence of paleoclimate Pine Island Glacier Cliff effect collapse during end of last ice age.

https://www.washingtonpost.com/news/energy-environment/wp/2017/10/26/new-science-suggests-the-ocean-could-rise-more-and-faster-than-we-thought/?tid=ss_tw&utm_term=.cf16ef3c6d1b

What’s critical about the markings, explains lead study author Matthew Wise of the University of Cambridge, is their maximum depth — 848 meters, or around 2,800 feet. Because ice floats with 10 percent of its mass above the surface and the remaining 90 percent below it, this suggests that when the ice broke from the glacier, close to 100 meters (over 3oo feet) of it was extending above the water surface.

That’s a key number, because scientists are converging on the belief that ice cliffs of about this height above the water level are no longer sustainable and collapse under their own weight — meaning that when you get a glacier this tall up against the ocean, it tends to crumble and crumble, leading to fast retreat and potentially fast sea level rise.

“If we think about how thick these icebergs would have needed to be considering these float with 90 percent of their mass and thickness beneath the sea,” Wise said, “we think of an ice cliff that was at the maximum thickness implied by the physics of the ice.”

The problem is that if it happened then, well, it could happen again. Both Pine Island glacier and its next door neighbor, Thwaites, are known to get thicker as one travels inland away from the sea, which means they are capable of once again generating ice cliffs taller than the critical size detected by the current study.

“If a cliff even higher than the ~100 m subaerial/900 m submarine cliffs were to form, as might occur with retreat of Thwaites Glacier in West Antarctica, it might break repeatedly with much shorter pauses than now observed, causing very fast grounding line retreat and sea level rise,” explained Richard Alley, a glaciologist at Penn State University, by email after reviewing the current study for the Post.

16
Consequences / Re: Conservative Scientists & its Consequences
« on: October 20, 2017, 04:06:16 PM »

17
Consequences / Re: Decline in insect populations
« on: October 20, 2017, 08:07:43 AM »
 :-X

18
Policy and solutions / Re: Boring, boring ol' Elon Musk...
« on: October 19, 2017, 11:41:21 PM »
Larry Hogan, Governor of the State of Maryland, confirmed that they are working with the company for a “rapid electric transportation” system between Baltimore and Washington DC...

34 miles, straight line.  All in the same state with backing from the governor.

180,000 feet.  60 feet per day with a regular (large diameter) tunneling machine.  3,000 days.  8.2 years.

Musk claims that eventually they should reach speeds of 840 feet per day.   214 days.  7 months.

Wonder how much faster Boring is now?  Smaller diameter will buy them a lot.  Of course they could drop in another machine or more in order to get a first line up and running.

I'm so lovin' this.  With robo taxis on each end of the run there would be almost no reason to drive one's own car between DC and Baltimore.

And this could do wonders for Baltimore's economy.  Turn it into a DC bedroom community.

pretty standard practice to work from both ends of the tunnel.

19
The rest / Re: Russiagate
« on: October 19, 2017, 06:09:57 PM »
It may be that there's a successful disinformation campaign to smear people like Obama and the Clintons, but isn't the reason it's so successful that there is something there?

Anyone who believes that Obama and the Clintons are above corruption has simply not been paying attention.

The Real News


Jimmy Dore

20
How a purchased government operates


21
Science / Re: Radiative forcing and CO2eq
« on: October 07, 2017, 05:42:23 PM »
That last graphic is very interesting.

It shows a net forcing from 1850 of +2.5

However, measurements of ocean heat content as a proxy for Top-of-Atmosphere radiation imbalance (see: https://www.ocean-sci.net/12/925/2016/os-12-925-2016.pdf ) show that our current radiation imbalance is between 0.8 and 1.2 W/m^2.

of course, the imbalance of radiation is partially offset by changes in albedo and through blackbody emissions that increase as the earth warms (and it is warmer than 1850).  Though all indications are that the total albedo forcing is slightly positive since 1850 (less reflective). 

This then shows that on a globally averaged value, the temperature must increase somewhat to offset the current top-of-atmosphere energy imbalance.  Since blackbody emissions increase at fourth-power scales the temperature increase necessary will be slightly less than what has been observed (~ 1 C)  so this means that on a globally averaged temperature  scale about 0.8C is locked in at current TOA imbalance. 

This warming will not occur on the ocean surface, however, as has happend in the past, this warming will be represented in arctic amplification and land surface temperatures warming more than ocean surface temperatures.  Likely in proportion to shifts seen since 1850.

Then one must consider the end of fossil fuels to halt growing CO2 emissions and the subsequent halt in SO2 emissions, with some reductions in forcing from shortlived climate polutants, perhaps (at a very best case) 2/3 of the SO2 positive impact from halting emissions can be offset by shortlive climate pollutants and we will receive another +.23C from those combined effects.

so another +1.0C from today's value

Then we must include carbon cycle feedbacks and albedo feedbacks that operate on very short timelines (30-80 years) and we have a big ol question mark of locked in warming.  It starts with a minimum value of 300 GtC additional emissions from warming soils to this 300 GtC (Crowther 2016) http://www.nature.com/nature/journal/v540/n7631/full/nature20150.html?cookies=accepted

to this then add emissions from deeper soils that were not included in the Crowther study and are as much as 30% more than the surface soils value in Crowther, yeilding a total emissions value of 400 GtC http://newscenter.lbl.gov/2017/03/09/soils-carbon-climate/ 

These studies are much less rigorous than the recently published published 26-year study on mid-latitude forest soil carbon by Woods Hole and the release from these sources under warming conditions are so great that they are seen to potentially be enough to drive a self-perpetuating warming effecthttp://www.mbl.edu/blog/carbon-feedback-from-forest-soils-will-accelerate-global-warming-26-year-study-projects/ 

Note that there are 3,600 GtC in mid-latitude forest soils

In addition, another woods hole study, this of tropical forest carbon flows, shows that they are now either net neutral or positive emitters of CO2, which is very different from previous assumptions that they are carbon sinks.  https://www.theguardian.com/environment/2017/sep/28/alarm-as-study-reveals-worlds-tropical-forests-are-huge-carbon-emission-source

Finally, the changes in albedo will also produce future warming as Arctic sea ice disappears and cloud regimes move further northward.  This cloud regime movement is implicated to produce the 9C ESS value of locked in warming potential at our current GHG forcing levels as shown in Snyder (2016) https://www.nature.com/nature/journal/v538/n7624/abs/nature19798.html

It should be noted here that the -1.2W/m^2 is a low-end estimate of the total forcing impact of SO2 emissions since it does not include many potential indirect feedbacks, especially potential impacts on tropical cloud regimes and pacific ENSO patterns.

22
Science / Re: Carbon Cycle
« on: October 06, 2017, 05:46:52 AM »
https://scienmag.com/carbon-feedback-from-forest-soils-will-accelerate-global-warming-26-year-study-projects/

WOODS HOLE, Mass. — After 26 years, the world's longest-running experiment to discover how warming temperatures affect forest soils has revealed a surprising, cyclical response: Soil warming stimulates periods of abundant carbon release from the soil to the atmosphere alternating with periods of no detectable loss in soil carbon stores. Overall, the results indicate that in a warming world, a self-reinforcing and perhaps uncontrollable carbon feedback will occur between forest soils and the climate system, adding to the build-up of atmospheric carbon dioxide caused by burning fossil fuels and accelerating global warming. The study, led by Jerry Melillo, Distinguished Scientist at the Marine Biological Laboratory (MBL), appears in the October 6 issue of Science.

Melillo, J.M. et al (2017) Long-Term Pattern and Magnitude of Soil Carbon Feedback to the Climate System in a Warming World. Science
http://science.sciencemag.org/content/358/6359/101

23
Consequences / Re: Conservative Scientists & its Consequences
« on: October 06, 2017, 05:26:31 AM »
I posted this over at forcing but wanted to share it here as well, it shows the impact that SO2 uncertainty has on potential ECS ranges and the resulting temperatures that would occur if we held forcing (GHG abundances) at today's values, also the potential warming that would occur due to SO2 emissions halting (see how high up the red line goes. . .) then other impacts of SLCP reduction centiennial forcing, not sure what that is exactly and carbon capture of the oceans, of course they do not include carbon cycle or arctic albedo feedbacks in these projections.

The big note here is the uncertainty in SO2 impacts on global temperatures and that, at today's forcing values, and in the absence of SO2 we could be locked in well over 3C of warming, though this is an outlier.

24
Consequences / Re: Conservative Scientists & its Consequences
« on: September 29, 2017, 02:08:23 AM »
it appears to me at the point of transition from seafloor highstand to inner deep recess that the loss of the ice sheet buttress would promote increased rates of flow from grounded glacier above sea level through plastic deformation. 

It seems that the transition here is really dependent on whether this increased surface flow/deformation has a limiting speed and if the rate of deep water undercutting once the seafloor rise is past is working faster than this surface flow outwards. 

IF it is not fast enough, then the increased collapse will move at a much faster rate and sea level rise will grow significantly through calving.

Much more, the potential increase in surface melt and rainfall events in WAIS under a much warmer world (guessing ~+4.0C here) would lead to additional structural weakening, increased internal heat and faster flows & slumping at the grounding line as it regresses back into the deep cavity.  This will work to prevent rapid undercutting, and reduce the cliff height.


25
Science / Re: Radiative forcing and CO2eq
« on: September 27, 2017, 06:06:33 PM »
Thanks for that info ASLR.

the Pliocene is our better analog imo.

Of course, we really do not have a good analog in the paleoclimate since the rate of changes in GMT is orders of magnitude faster today than ever before.  The implications of lagging ocean surface temperatures coupled with ice sheet and glacier instability is explored by the Hansen work you cite. 

WRT WAIS this:  between 119 kyr and 118.1+/- 1.4 kyr is shocking but since the range of 3m rise goes to a negative value the uncertainty could mean 'instantaneous' or 'over 2,300 years'  Certainly not definitive.

the polar amplification trend under a regime of atmospheric translation of water vapor and associated latent heat to the poles, with implied changes in global atmospheric circulation regimes in the Hadley, Walker and Polar cells will be the big uncertainty that may drive this process more rapidly, though this will impact Greenland much more than Antarctica in the near term with WAIS primarily being reduced through regional warming and freshening of the Circumpolar Deep Water, as was recently observed through sea floor core sample analysis during the Pliocene.  https://link.springer.com/article/10.1007/s00367-016-0489-8

however, at this time I feel we have kind of hijacked this thread with off-topic discussion, can we relocate to a more appropriate thread for this? 

26
Arctic sea ice / Re: The 2017/2018 freezing season
« on: September 26, 2017, 03:21:14 AM »
Excellent summary of the 2017 season here:https://news.mongabay.com/2017/09/at-2017-minimum-scientists-ask-is-arctic-entering-the-thin-ice-age/

27
Science / Re: Radiative forcing and CO2eq
« on: September 25, 2017, 01:05:42 AM »
your concern is of course extremely valid, however, the timeline of 'collapse' in MIS-11 (and 5e) could be quite long.

https://s3.amazonaws.com/academia.edu.documents/45688326/science.281.5373.8220160516-12353-xh71hl.pdf?AWSAccessKeyId=AKIAIWOWYYGZ2Y53UL3A&Expires=1506297450&Signature=sCqwwOT7ZXrIpY8yBwIvq3rHWUw%3D&response-content-disposition=inline%3B%20filename%3DPleistocene_collapse_of_the_West_Antarct.pdf

interestingly, there is strong indication of east and central Antarctic ice mass gains during MIS-11 due to increased precipitation  https://www.nature.com/articles/srep41433?WT.feed_name=subjects_earth-and-environmental-sciences

the total contribution of sea level rise during MIS-11 from Greenland is gauged to be 6 meters though it took thousands of years to accomplish that melt.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5504289/

this value represents between 75% and 50% of the total potential range of sea level rise (9-12 Meters) during MIS-11  https://www.clim-past.net/12/1079/2016/cp-12-1079-2016.pdf

28
Arctic sea ice / Re: Stupid Questions :o
« on: September 25, 2017, 12:56:05 AM »
great noaa article on vertical wind shear and its impacts on hurricanes.  The projected increase in this negative force that suppresses hurricane formation within a warming world is one of the reasons many models predict fewer total hurricanes but stronger ones when they do form.

http://www.aoml.noaa.gov/keynotes/keynotes_0715_windshear.html

29
Science / Re: Radiative forcing and CO2eq
« on: September 24, 2017, 07:45:49 PM »
https://twitter.com/Peters_Glen/status/911889196905668609

RF from GHG reaches double CO₂ value (3.7W/m²) in ~2030, but total RF will remain close to CO₂ with aerosol cooling http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo3036.html


30
Consequences / Re: Hurricane season 2017
« on: September 21, 2017, 01:49:34 AM »
the 'big three' (so far) cat 4 u.s. landfalling hurricanes

31
Consequences / Re: Hurricane season 2017
« on: September 21, 2017, 01:46:49 AM »
Puerto Rico's Emergency Manager "Puerto Rico is Destroyed"

https://www.nbcnews.com/news/weather/hurricane-maria-makes-landfall-puerto-rico-category-4-storm-n802911

"Once we're able to go outside, we're going to find our island destroyed," Emergency Management Director Abner Gómez Cortés said at a news briefing. Rosselló imposed a 6 p.m.-to-6 a.m. curfew, citing flood warnings and the importance of keeping streets clear for repair and rescue teams.

 San Juan San Juan Mayor Carmen Yulín Cruz told MSNBC that the devastation in the capital was unlike any she had ever seen.

"The San Juan that we knew yesterday is no longer there," Yulín said, adding: "We're looking at four to six months without electricity" in Puerto Rico, home to nearly 3.5 million people.

. . . four to six months. . .

32
Policy and solutions / Re: Solar Roadways
« on: September 20, 2017, 10:47:30 PM »
form most conditions, even cloudy skies, if a portion of the panel's snow is removed, the generation of electricity will warm the surface of the panel and cause snow to slide off.

Just need to have a way to clear a small portion of the panel.

33
Science / Re: Radiative forcing and CO2eq
« on: September 20, 2017, 07:14:15 PM »
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.

Is this a major deviation from what has currently been assumed? if so, this is pretty cutting-edge stuff!

Not really.  Many have claimed that the radiative impact is quite high.  Others not so much.  This is still a highly debated topic.

I meant about the inter-hemispheric amplication.

34
Science / Re: Radiative forcing and CO2eq
« on: September 20, 2017, 07:03:26 AM »
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.

Is this a major deviation from what has currently been assumed? if so, this is pretty cutting-edge stuff!

35
Consequences / Re: Hurricane season 2017
« on: September 20, 2017, 02:05:08 AM »
These wind field maps

cold chills


36
Science / Re: Radiative forcing and CO2eq
« on: September 19, 2017, 07:06:50 PM »
erring on the side of least drama

I'd once again like to politely request that you leave that shtick in one of the many other threads where it's already commonplace, e.g.,

Topic: Conservative Scientists & its Consequences

Part of the reason I started this thread was to get away from the sneering and insults that have been proliferating elsewhere.  In my experience scientists generally try to err on the side of least ERROR, and it is polite to assume that everyone, even those with whom we disagree, are following that in good faith. 

Obviously I can't enforce decorum and assumption of good faith here; this is just a polite request.

There are two basic categories of error in science.

The tendency to have one kind of error is much more likely than the other in science.

To state that the reason that this well documented error bias is cultural (among scientists) is within the auspices of sociologists who study science.

To find and state that the guiding cultural driver that causes scientists to have an overwhelming prevalence of Type II errors (see: http://sciencepolicy.colorado.edu/admin/publication_files/2014.34.pdf ) is due to an aversion of the 'drama' (really: a risk to credibility) caused by having a Type I error is not an insult or 'dig', it is a function of the studies of social sciences.


37
Policy and solutions / Re: Solar Roadways
« on: September 19, 2017, 07:00:03 PM »
Implementing this technology in a manner that has any real impact on AGW is wildly impractical and hopelessly unaffordable.

Didn't they say that solar panels would be impractical as a bulk energy source?

The thing is, if the durability of these systems becomes much stronger than now, they could offset costs of resurfacing and repaving that run in the order of 1.4 million per mile for a 4 lane road.  expansion from 4 to 6 lanes costs 5 million per mile.  Repaving schedules vary but typically run every 5 years based on traffic conditions.

In addition, there are massive emissions currently associated with the production, transport and installation/repaving of roads.  From an AGW perspective this makes a big difference. 

Finally, upon the successful implementation of high-effective capacitors for use by EVs during operations where they charge WHILE DRIVING, the feasibility of solar roads looks much more feasible.  I still expect these only to be ever really used in the south-west desert states, but hey, who knows. . .

38
Consequences / Re: Global Surface Air Temperatures
« 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

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:

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

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. . .  >:( )


39
Science / Re: Radiative forcing and CO2eq
« on: September 19, 2017, 05:47:10 PM »
RE: Aerosols

*cough*

http://iopscience.iop.org/article/10.1088/1748-9326/aa5dd8

Here we show evidence from observations and climate models that external forcing largely governs decadal GMST variations in the historical record with internally generated variations playing a secondary role, except during those periods of IPO extremes. . . The most recent warming hiatus apparent in observations occurred largely through cooling from a negative IPO extreme that overwhelmed the warming from external forcing.

and

http://www.nature.com/nclimate/journal/v6/n10/full/nclimate3058.html

The prevailing view is that this negative PDO occurred through internal variability.  However, here we show that coupled models from the Fifth Coupled Model Intercomparison Project robustly simulate a negative PDO in response to anthropogenic aerosols implying a potentially important role for external human influences. . . Our results suggest that a slowdown in GMST trends could have been predicted in advance, and that future reduction of anthropogenic aerosol emissions, particularly from China, would promote a positive PDO and increased GMST trends over the coming years.

note:  This is also directly related to ASLR's post above as negative IPO absorbs much more forcing in the ocean and +IPO returns this heat energy to the atmosphere.

40
Science / Re: Radiative forcing and CO2eq
« on: September 19, 2017, 06:38:31 AM »
Well, nobody really needs the concept of CO2e -- one can just sum up the forcings and leave it at that, in W m-2, rather than fake CO2 ppmv. 

Understanding effective radiative forcing is a good idea as expressed in the linked reference that provides a summary of the latest IPCC thinking on anthropogenic aerosols & their impact on global climate.  The reference states: "From 1850 to 2010, anthropogenic aerosols brought about a decrease of ∼2.53 K and ∼0.20 mm day−1 in global annual mean surface temperature and precipitation, respectively."  Therefore, as we are already over a +1C value of GMSTA, if we dropped back to 1850 levels of aerosols we might increase GMSTA to over +3.5C, even if we dropped to zero emissions of CO2 by switching 100% to solar & wind power today:

Hua Zhang, Shuyun Zhao, Zhili Wang, Xiaoye Zhang & Lianchun Song (25 January 2016), "The updated effective radiative forcing of major anthropogenic aerosols and their effects on global climate at present and in the future", International Journal of Climatology, DOI: 10.1002/joc.4613

http://onlinelibrary.wiley.com/doi/10.1002/joc.4613/abstract

Abstract: "The effective radiative forcing (ERF), as newly defined in the Intergovernmental Panel on Climate Change's Fifth Assessment Report (IPCC AR5), of three anthropogenic aerosols [sulphate (SF), black carbon (BC), and organic carbon (OC)] and their comprehensive climatic effects were simulated and discussed, using the updated aerosol-climate online model of BCC_AGCM2.0.1_CUACE/Aero. From 1850 to 2010, the total ERF of these anthropogenic aerosols was −2.49 W m−2, of which the aerosol–radiation interactive ERF (ERFari) and aerosol–cloud interactive ERF (ERFaci) were ∼ −0.30 and −2.19 W m−2, respectively. SF was the largest contributor to the total ERF, with an ERF of −2.37 W m−2. The ERF of BC and OC were 0.12 and −0.31 W m−2, respectively. From 1850 to 2010, anthropogenic aerosols brought about a decrease of ∼2.53 K and ∼0.20 mm day−1 in global annual mean surface temperature and precipitation, respectively. Surface cooling was most obvious over mid- and high latitudes in the northern hemisphere (NH). Precipitation change was most pronounced near the equator, with decreased and increased rainfall to the north and south of the equator, respectively; this might be largely related to the enhanced Hadley Cell in the NH. Relative humidity near surface was increased, especially over land, due to surface cooling induced by anthropogenic aerosols. Cloud cover and water path were increased, especially in or near the source regions of anthropogenic aerosols. Experiments based on the Representative Concentration Pathway (RCP) 4.5 given in IPCC AR5 shows the dramatic decrease in three anthropogenic aerosols in 2100 will lead to an increase of ∼2.06 K and 0.16 mm day−1 in global annual mean surface temperature and precipitation, respectively, compared with those in 2010."

My god, I forgot about that.  Wasn't that paper somewhat challenged by the climate scientific body, I mean ascribing a 2C increase SOLELY to the removal of SO2 from our emission profile and adding that to the current warming ~1.1C AND locked-in warming from current GHG forcing ~0.6C AND future warming from carbon cycle feedbacks ~1.3C by 2100 (this is a very low estimate) would mean that we have already locked in a +5.0C world at today's GHG levels!

Talk me down ASLR!!!! IMA bout 2 jump. . .

41
Science / Re: Radiative forcing and CO2eq
« on: September 19, 2017, 06:32:41 AM »
There is a lot of uncertainty in these estimates.  Faster reduction in aerosols would increase the rate of warming, while faster reduction in ozone would decrease warming.

Those are great graphics. 

There is a lot of uncertainty in the emissions rates going forward but there is even MORE uncertainty in the total forcing impact of SO2, including impacts on cloud physics and on the ENSO and AMO. 

42
Policy and solutions / Re: Solar Roadways
« on: September 19, 2017, 06:24:18 AM »
Dave, most excellent and enthusiastic video blogger, trustworthy source on all things electronic:


more than a little disingenuous to compare metered values from the Netherlands when looking at potential installation in Arizona (Arizona gets more than twice as much annual sunshine)

http://www.webberenergygroup.com/test/html/iii-renewable-energy/chapter-14-INDD-web-resources/image/NREL-pv-map-us-germany-spain.jpg

43
Consequences / Re: Hurricane season 2017
« on: September 19, 2017, 06:17:11 AM »
what the HELL is Jose doing?  Waiting in the wings for Maria to come up so that they can do the Fujiwhara shuffle???

https://earth.nullschool.net/#2017/09/23/0600Z/wind/surface/level/orthographic=-83.22,33.15,1879/loc=-73.047,25.250

I am at a total loss at this, it just doesn't feel right. 

I guess the biggest issue is, how accurate can the models be now that we have hurricanes jumping 2 categories above model projections in only 24 hours and a stationary hurricane off of the New England coastline???

Seriously, long range forecasts show Jose doing ANOTHER loop and possibly moving west with a major hurricane Maria moving into the U.S. south. . . it baffles the mind. . .

44
Science / Re: Radiative forcing and CO2eq
« on: September 17, 2017, 11:06:10 PM »
It should also be noted that the NOAA AGGI value that matches yours also does not include increased water vapor or other feedbacks in their estimation of comparative total forcing. 

Did you include these values in your total anthropogenic CO2eq?
Those are feedbacks, not forcings.  Forcings are used as inputs to the models, while feedbacks are represented by processes within the models.

To be clear, the models used to develop NOAA AGGI CO2eq forcing values do NOT include feedbacks that result from GCM model outputs.  However, we do have good satellite records of recent atmospheric water vapor increases and their additional forcing values can be extracted (with high uncertainty in comparison to 1750 values).


45
Science / Re: Radiative forcing and CO2eq
« on: September 17, 2017, 03:49:24 PM »
It should also be noted that the NOAA AGGI value that matches yours also does not include increased water vapor or other feedbacks in their estimation of comparative total forcing. 

Did you include these values in your total anthropogenic CO2eq?

46
Science / Re: Radiative forcing and CO2eq
« on: September 17, 2017, 03:19:22 PM »
Isaksen also followed up the above 2011 paper with a 2014 paper that looked specifically at the impacts of increased emissions of CH4 from transportation and the Arctic in future years, as well as the climate feedbacks of increased Ozone production in a warming world.  see paper here: http://www.mdpi.com/2073-4433/5/3/518/htm

The chemistry balance shifts of Stratospheric water vapor and Ozone, and their increased forcing potentials are shown in table 2 and below.

Most concerning to me is the translation of the increased radiative forcing of Methane, and the resultant increase in tropopause heights as an additional warming feedback on the evaluation of Global Warming Potential of these short-lived climate pollutants.  If applied as an equal adjustment for both the GWP-100 and the GWP-20 then the adjusted multiplier of CO2e for methane under GWP-100 (35) and GWP-20 (105) increase to (37.4) and (112.1) respectively, and if emissions rates of CH4 are held constant over time.

However, since CH4 only exists in the upper atmosphere for 10-12 years, the relative impacts from this gas are front-loaded and since this front-loading results in a ~7% increased RF on the 100-year GWP then it stands to reason that under a shift to GWP-20 this effect would increase at a much higher rate than the GWP-100 value.

This very complex atmospheric chemistry issue, under varying climate conditions, requires updated inputs into complex chemistry transport models and GCMs to winnow out the total warming impacts.

note: an excellent reference describing these chemistry interactions from Daniel Jacobs' Introduction to Atmospheric Chemistry - 1999 Can be found here:  http://acmg.seas.harvard.edu/people/faculty/djj/book/bookchap11.html

full online book here: http://acmg.seas.harvard.edu/people/faculty/djj/book/

47
Science / Re: Radiative forcing and CO2eq
« on: September 17, 2017, 05:56:59 AM »
Using all anthropogenic forcings (from here) the CO2eq values are approximately 422 ppmv (old) and 432 ppmv (new).

Thanks for your response and your work this looks very interesting, The NOAA AGGI CO2eq for 2016 is calculated to be (see: https://www.esrl.noaa.gov/gmd/aggi/ ) 489 ppm. 

From their methodology paper here:  https://www.esrl.noaa.gov/gmd/aggi/aggi.html

See table 2, the values you have come up to theirs quite well 2016 CO2e


48
Science / Re: Radiative forcing and CO2eq
« on: September 16, 2017, 06:08:11 PM »
Since Etminan 2016 states the 2011 differential value of forcing for CH4 to be +0.13, and you have previously stated that this value is too high, please post your "previous" and "new" values for CH4 for the year 2011.  If it is less (or more!) than 0.13 Watts per meter squared then your calculation is off.

Note that the relative values is not important here, only the differential, since you are using a different baseline than he does (1750).

I understand you are only looking at the "big three" (CO2, CH4 and NO2) so when you post your CO2eq values you need to note that you are excluding the additional forcing from O3 (0.4 W/m^2) and trace GHGs (0.339 W/m^2).  This additional forcing (using the pre-Etminan values produces a real CO2eq value of 526.6 ppmv The additional forcing of Etminan increases this value somewhat. 

http://cdiac.ess-dive.lbl.gov/pns/current_ghg.html

49
Consequences / Re: Hurricane season 2017
« on: September 16, 2017, 12:26:00 AM »
Disturbance 1 looks very significant in the Caribbean (and on toward Florida) on the long-range models, Hurricane Jose looks to be more than insignificant with wind-speed and storm surge damage to New England.

https://earth.nullschool.net/#2017/09/20/1200Z/wind/surface/level/orthographic=-69.52,27.91,818/loc=-162.147,14.467

50
Consequences / Re: Hurricane season 2017
« on: September 16, 2017, 12:22:51 AM »
. . . and then it will be too late anyway.

Talk about not helping.   It is a simple fact of human nature that we are basically herd animals who need to see concrete physical action or threat to get behind something.  In the absence of a rational, moral and representational government who has effectively denied climate change and its threats for the last 30 years, It will likely take continued impacts, coupled with local-scale movements eventually catalyzing into a national-scale movement, like occupy wall street, before our government actually does the hard work of saying 'NO' to their wealthy fossil-fuel interest donors and lobbyists.

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