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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Sep 19, 2014 - 09:32pm PT
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So, who among you are going to attend events this sunday to mark solidarity with the big (or maybe small, who in the hell knows with these kinds of forced events) march for climate in New York City?
If you are , it might be good to keep in mind that Antarctica has again set a new all time high for sea ice, exceeding 20, 000, 000 km2. If you include the continental ice and shelf ice there is a total of 37, 500, 000 km2 of reflective Ice surrounding the south pole now. Besides indicating distinct cooling (new all time modern earth minimum temps set there in recent years), does this great increase in ice indicate we are near a tipping point in our present glacial epoch? Could we see ice growing to South America in the 21st century?
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k-man
Gym climber
SCruz
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Topic Author's Reply - Sep 20, 2014 - 07:42am PT
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Sketch, what is the cause the the record-breaking Antarctic sea ice extent?
What meaning do your graphs have?
In the Antarctic, the trend is opposite to that in the Arctic, with the sea ice cover increasing at about 1 to 2 % per decade. This is despite unusual warming in the Antarctic Peninsula region and declines in the sea ice cover in the Amundsen/Bellingshausen Seas of about 6% per decade.
So yeah, the trend is that the Antarctic sea ice is slowly increasing, but why?
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k-man
Gym climber
SCruz
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Topic Author's Reply - Sep 20, 2014 - 08:02am PT
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Have you got a "mind blowing" valid and accurate number of all them climate scientists with a valid ref... not from some pro-AGW totally bias blog.
Sorry The Chief, all I could find was this NASA article:
http://climate.nasa.gov/scientific-consensus/
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HighTraverse
Trad climber
Bay Area
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Sep 20, 2014 - 12:01pm PT
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You're a smart guy. I'm sure you can find the answer you want with a little effort. I can't tell if this is meant seriously or is a sarcastic response.
From reading the previous few posts I get the idea that "extent of antarctic sea ice" might be misunderstood.
To be perfectly clear:
"sea ice" is the ice in the ocean, not contained in glaciers, snowfields or other land phenomena.
So where does sea ice come from?
Certainly not the ocean. Sea ice comes from disintegrating icebergs and glaciers/snowfields calving into the sea.
Therefore sea ice increases the volume of the oceans and is one of the two major components of sea level rise. The other is the expansion of the oceans due to rising temperature (heat makes most materials, including sea water, expand)
SO an increase in sea ice (extent of) indicates an increased flow of land ice into the sea and a decrease of glacier/snowfield mass.
simple mind experiment:
take a tray of ice cubes and a glass of water.
Remove one cube and drop it in the water.
3 questions:
Did you have to warm up the tray of ice to get a cube out?
what happens to the level of water in the glass?
how much of the ice cube actually floats above the water?
Now think on the antarctic scale.
EDIT:
Splater. Thanks for your corrections. Looks as if I need to re-read the topic.
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Splater
climber
Grey Matter
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Sep 20, 2014 - 12:32pm PT
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HT,
before you get too carried away,
keep in mind that Sketch is mainly just a troll, trying to screw with people, but rarely showing much interest in science. In this case his wording "find the answer you want," actually does have some meaning behind it, although he as usual doesn't put much effort into discussing it.
There is no clear explanation or model for the increased southern sea ice,
so that's why you can find various answers.
But here are some of the proposed explanations for more Antarctic sea ice, despite lack of colder temperatures:
 Higher winds that blow ice further from land, creating more cold area near the continent to create more sea ice, filling the gaps.
More melting from land ice that add ice and freshwater to sea which has a higher freezing point than saltwater.
Increased precipitation in the area, (fresh water + slush that freezes easily)
http://www.slate.com/blogs/future_tense/2014/09/18/antarctic_sea_ice_is_hitting_record_levels_what_does_that_say_about_global.html
Ice that breaks off from land ice caps does add to ocean volume, which is happening with all land ice caps. But sea ice is generally just frozen ocean which does not increase ocean volume.
It's easier to picture that in the Arctic, where there is less land ice to make a difference (not counting Greenland).
In the meantime, in the Global world (instead of cherry picking),
Global indicators show that Global warming has not slowed.
http://climate.nasa.gov/key_indicators/#co2
http://www.nasa.gov/mission_pages/Grace/multimedia/index.html
http://www.ncdc.noaa.gov/sotc/global-snow/2014/8
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Splater
climber
Grey Matter
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Sep 20, 2014 - 03:32pm PT
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Ah yes... the "throw sh#t against the wall and see what sticks" approach. Kind of like the excuses... er... um... I mean the possible explanations for the prolonged hiatus. In a nutshell, our climate experts aren't as smart as they'd like us to think. The science isn't settled. ;-)
That's not how it works, unless you get your info from denialist blogs. When data does not fit a general model, scientists have to figure out why, and how to improve. So they theorize, measure, test, model, which does not happen overnight, especially in Antarctica. And then the model becomes even more accurate, just as UCAR is now able to hindcast recent surface temperatures.
The Antarctic sea ice extent is setting a new record high. The Arctic sea ice extent minimum will be greater than 5 of the last 7 minimums... The combined Northern and Southern Hemisphere sea ice extents during august was above the 1981-2010 average.
More cherry picking.
The general trend of Global ice extent is downward. Only in spring is there no clear and significant downward trend. Pick a month at
http://www.ncdc.noaa.gov/snow-and-ice/extent/sea-ice/G/0
Another downward trend is snow cover
http://www.ncdc.noaa.gov/snow-and-ice/extent/snow-cover/nhland/0
//"Antarctica melting, resulting in flooding on every coast on the planet.
Remember this?"//
Didn't I just post this? Antarctica and Greenland are clearly Melting.
http://climate.nasa.gov/key_indicators/#landIce
http://www.nasa.gov/mission_pages/Grace/multimedia/index.html
Is sea level not rising?
http://climate.nasa.gov/key_indicators/#seaLevel
And the main point in the long run is not the present exact rate of rise.
The point is what do climate scientists predict for the future rate.
All models say the rate will accelerate, based on the effects of the primary driving forces.
Denialists want to wait until after it happens (when they may be dead), saying predictions can be ignored.
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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Sep 20, 2014 - 03:49pm PT
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HT- what makes you think antarctic land ice is losing mass as it slides into the sea thereby increasing sea ice? Before you pass a "groupthink programmed" judgement you should read up a bit. Zwally et al 2012 used Icesat data and came to the conclusion that the continental ice mass is gaining , not decreasing. Continental glaciers may be spilling to the sea, but the main reason for Increased sea ice is cold air temps, cold waters and perhaps increased precip. Same as the Arctic which has incrsased in extent 60% in the last two years.
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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Sep 20, 2014 - 05:46pm PT
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Hey Chief and Sketch. That hollywood gang could share a ride back in a gulfstream to their ocean front estates, no? Or would that be bad form for people of their stature? Whatcha think HT, should we demand they lead by example?
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k-man
Gym climber
SCruz
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Topic Author's Reply - Sep 20, 2014 - 09:27pm PT
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Sketch, what is the cause the the record-breaking Antarctic sea ice extent?
I don't know.
So, Sketch posts graphs without any idea what they mean.
Standard.
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Wade Icey
Trad climber
www.alohashirtrescue.com
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Sep 20, 2014 - 10:28pm PT
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Ed Hartouni
Trad climber
Livermore, CA
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Sep 20, 2014 - 10:36pm PT
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of course, Sketch doesn't quote his sources... I would ask Sketch what issue of Nature had that cover, and what the articles actually wrote about the issue, but Sketch wouldn't know... it is some political theatre for him...
Sketch asks "remember this?" but how could it be remembered if it were never really experienced? I suspect that linking the fact that there is still ice in antarctica to a prestigious scientific journal Nature and claiming that this is some contradiction makes a case...
the image linked is from the site:
http://www.worldclimatereport.com
without which Sketch wouldn't have even known such a cover existed.
It is the cover to Nature 457 issued on January 22, 2009...
http://www.nature.com/nature/journal/v457/n7228/index.html
and it appears to be infamously circulated around the blog sphere as being "wrong," well, actually it was a particular article:
ftp://ftp.soest.hawaii.edu/coastal/Coastal%20Geology%20Class%20GG420/Steig_2009%20antarctic%20warming.pdf
Warming of the Antarctic ice-sheet surface since the 1957 International Geophysical Year
Eric J. Steig, David P. Schneider, Scott D. Rutherford, Michael E. Mann, Josefino C. Comiso & Drew T. Shindell
Assessments of Antarctic temperature change have emphasized the contrast between strong warming of the Antarctic Peninsula and slight cooling of the Antarctic continental interior in recent decades1. This pattern of temperature change has been attributed to the increased strength of the circumpolar westerlies, largely in response to changes in stratospheric ozone2. This picture, however, is substantially incomplete owing to the sparseness and short duration of the observations. Here we show that significant warming extends well beyond the Antarctic Peninsula to cover most of West Antarctica, an area of warming much larger than previously reported. West Antarctic warming exceeds 0.1ºC per decade over the past 50 years, and is strongest in winter and spring. Although this is partly offset by autumn cooling in East Antarctica, the continent-wide average near-surface temperature trend is positive. Simulations using a general circulation model reproduce the essential features of the spatial pattern and the long-term trend, and we suggest that neither can be attributed directly to increases in the strength of the westerlies. Instead, regional changes in atmospheric circulation and associated changes in sea surface temperature and sea ice are required to explain the enhanced warming in West Antarctica.
I'm sure that Sketch doesn't remember that either, but also has no reason to remember an unread article...
Putting the title into Google Scholar reveals that 366 articles have cited this one.
Usually when someone puts an article up in such a journal as Nature it attracts scientific attention and if it is wrong there are on scientists who would not publish the challenge...
So looking at this list we find recent articles like this:
http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3656.1
J. Climate, 24, 2099–2115.
Improved Methods for PCA-Based Reconstructions: Case Study Using the Steig et al. (2009) Antarctic Temperature Reconstruction
Ryan O’Donnell, Nicholas Lewis, Steve McIntyre, Jeff Condon
A detailed analysis is presented of a recently published Antarctic temperature reconstruction that combines satellite and ground information using a regularized expectation–maximization algorithm. Though the general reconstruction concept has merit, it is susceptible to spurious results for both temperature trends and patterns. The deficiencies include the following: (i) improper calibration of satellite data; (ii) improper determination of spatial structure during infilling; and (iii) suboptimal determination of regularization parameters, particularly with respect to satellite principal component retention. This study proposes two methods to resolve these issues. One utilizes temporal relationships between the satellite and ground data; the other combines ground data with only the spatial component of the satellite data. Both improved methods yield similar results that disagree with the previous method in several aspects. Rather than finding warming concentrated in West Antarctica, the authors find warming over the period of 1957–2006 to be concentrated in the peninsula (≈0.35°C/decade). This study also shows average trends for the continent, East Antarctica, and West Antarctica that are half or less than that found using the unimproved method. Notably, though the authors find warming in West Antarctica to be smaller in magnitude and find that statistically significant warming extends at least as far as Marie Byrd Land. This study also finds differences in the seasonal patterns of temperature change, with winter and fall showing the largest differences and spring and summer showing negligible differences outside of the peninsula.
which finds warming extending into West Antarctica...
...and this one
http://polarmet.osu.edu/PMG_publications/bromwich_nicolas_ngeo_2013.pdf
Bromwich, David H., et al. "Central West Antarctica among the most rapidly warming regions on Earth." Nature Geoscience 6.2 (2013): 139-145.
Central West Antarctica among the most rapidly warming regions on Earth
David H. Bromwich, Julien P. Nicolas, Andrew J. Monaghan, Matthew A. Lazzara, Linda M. Keller, George A. Weidner and Aaron B. Wilson
There is clear evidence that the West Antarctic Ice Sheet is contributing to sea-level rise. In contrast, West Antarctic temperature changes in recent decades remain uncertain. West Antarctica has probably warmed since the 1950s, but there is disagreement regarding the magnitude, seasonality and spatial extent of this warming. This is primarily because long-term near-surface temperature observations are restricted to Byrd Station in central West Antarctica, a data set with substantial gaps. Here, we present a complete temperature record for Byrd Station, in which observations have been corrected, and gaps have been filled using global reanalysis data and spatial interpolation. The record reveals a linear increase in annual temperature between 1958 and 2010 by 2.4 ± 1.2ºC, establishing central West Antarctica as one of the fastest-warming regions globally. We confirm previous reports of West Antarctic warming, in annual average and in austral spring and winter, but find substantially larger temperature increases. In contrast to previous studies, we report statistically significant warming during austral summer, particularly in December–January, the peak of the melting season. A continued rise in summer temperatures could lead to more frequent and extensive episodes of surface melting of the West Antarctic Ice Sheet. These results argue for a robust long-term meteorological observation network in the region.
doesn't quite sound like a refutation of the original article... but who'd remember?
So 5 years after the article that "drew" that Nature cover, it would seem that the article has been substantiated by followup research published in the scientific literature... addressing the criticisms of the original paper... and extending the scientific observations.
...but who'd remember?
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Ed Hartouni
Trad climber
Livermore, CA
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Sep 21, 2014 - 08:13am PT
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good article by Steve...
which has been a part of the discussion here (if you remember to listen to the discussion here)
Rather, the crucial, unsettled scientific question for policy is, "How will the climate change over the next century under both natural and human influences?" Answers to that question at the global and regional levels, as well as to equally complex questions of how ecosystems and human activities will be affected, should inform our choices about energy and infrastructure.
and it is what climate scientists are doing, I'd hazard a guess that all of them are (all that are active).
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k-man
Gym climber
SCruz
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Topic Author's Reply - Sep 21, 2014 - 08:25am PT
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I don't know.
So, Sketch posts graphs without any idea what they mean.
Same old K-man... criticism based on a lie.
A typical response from Sketch, turning to ad hominem attacks when he is handed his ass in a hat.
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Ed Hartouni
Trad climber
Livermore, CA
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Sep 21, 2014 - 09:36am PT
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The 'ten years before its too late' doomsayers hurt the cause by nudging people like me away from action, my eyes rolling, muttering. You scientists should tell them to shutthef*#k up and not just in private. When you see a fellow traveler make outlandish or simply unsupported claims regarding future impact, how about calling them on it.
you are incapable of understanding the scientific case and are susceptible to following your emotional responses, therefore, it's not your fault for being "nudged away from action" for years?
weak response...
you claim to have been put back on track by the scientists who have posted to this thread, and who have from time to time, called out "fellow travelers" on their unsupported claims.
attempts to raise the level of the scientific discussion fail simply because the issues are much less controversial when you're talking about what the probability distribution function is appropriate for characterizing the uncertainty of the "equilibrium temperature"...
fact is, not many reading have any idea of what a "probability distribution function" is or why it might matter to the discussion.
Being a passionate person, you demand passionate responses... you get it in spades here, and it tends to overwhelm the less passionate, but perhaps more informative posts.
Policy discussions include understanding the uncertainties, and crafting something that takes into account the evolving state of knowledge. For instance, we know a lot more today about the past climate than we did even 5 years ago, and similarly, we are concerned with differences in our predictions on time and area scales which are regional, a goal of the science just 5 years ago...
A scientist can best represent the science... you want to know what sea ice extent is in antarctica and what the measurements mean, you have to wade into a large set of questions that scientists are asking themselves now... thinking about it as hypothesis testing is a great way to prepare to for hypothesis-observation challenges, which almost always end up with the death of the hypothesis... yet some how we learn what the consistent hypotheses are, and go on to make future ones... and make progress at understanding.
So in the sense that the "science is settled" or the "science is not settled" it is a dynamic which requires some definitions of what "settled" means, how science copes with change, and how it moves forward. None of which helps the discussion of policy, of which the science, and it's quantifiable uncertainties, play a part in making, but only a part.
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Ed Hartouni
Trad climber
Livermore, CA
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Sep 21, 2014 - 09:48am PT
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• The models predict that the lower atmosphere in the tropics will absorb much of the heat of the warming atmosphere. But that "hot spot" has not been confidently observed, casting doubt on our understanding of the crucial feedback of water vapor on temperature.
check the underline as a key to understanding what Koonin is saying here...
http://www.pnas.org/content/110/1/26.full
Identifying human influences on atmospheric temperature
Benjamin D. Santer, Jeffrey F. Painter, Carl A. Mears, Charles Doutriaux, Peter Caldwell, Julie M. Arblaster, Philip J. Cameron-Smith, Nathan P. Gillett, Peter J. Gleckler, John Lanzante, Judith Perlwitz, Susan Solomon, Peter A. Stott, Karl E. Taylor, Laurent Terray, Peter W. Thorne, Michael F. Wehner, Frank J. Wentz, Tom M. L. Wigleyd, Laura J. Wilcox, and Cheng-Zhi Zou
http://www.pnas.org/content/104/39/15248.full
Identification of human-induced changes in atmospheric moisture content
B. D. Santer, C. Mears, F. J. Wentz, K. E. Taylor, P. J. Gleckler, T. M. L. Wigley, T. P. Barnett, J. S. Boyle, W. Brüggemann, N. P. Gillett, S. A. Klein, G. A. Meehl, T. Nozawa , D. W. Pierce, P. A. Stott, W. M. Washington , and M. F. Wehner
http://onlinelibrary.wiley.com/doi/10.1029/2002JD002258/full
Behavior of tropopause height and atmospheric temperature in models, reanalyses, and observations: Decadal changes
B. D. Santer, R. Sausen, T. M. L. Wigley, J. S. Boyle, K. AchutaRao, C. Doutriaux, J. E. Hansen, G. A. Meehl, E. Roeckner, R. Ruedy, G. Schmidt andK. E. Taylor
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wilbeer
Mountain climber
Terence Wilson greeneck alleghenys,ny,
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Sep 21, 2014 - 09:50am PT
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Just for the record,you can call me a warmest,go ahead.I have never seen Gores film,don't care about hollywood and could care less about the machine known as the media.
I support the science and it's members.
I am part of the majority of this world that believes that CC IS REAL.
Not a doomsayer,never once and believes something can and will be done with our problem.
I do believe it will force our hand.
I support The Science and those around it.
http://www.sustainablecampus.cornell.edu/blogs/news/posts/cornell-professors-support-president-s-statements-on-climate-change
Throw em under the bus,It does not matter.For it and everything is political.
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Ed Hartouni
Trad climber
Livermore, CA
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Sep 21, 2014 - 09:58am PT
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...the column-integrated atmospheric moisture content over oceans...
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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Sep 21, 2014 - 10:02am PT
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The article by Koonin seemed a conciliatory and frank discussion of the limitations of modeling while still not abandoning the vehicle the fellow travelers have absconded public funds to propel.
Many of histories most evil and destructive regimes have projected stances that at times have seemed reasonable while invoking scientific or religious "truths" to underpin the twisted logic of their goals. This AGW is no different than the Nazis.
There is no reasoning, or mediation with this kind of mentality, you cannot meet them in the middle or negotiate an acceptable treaty.
If these types come bearing an olive branch, take it and flog them with it.
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