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jetfuel at 10:59 AM on 14 August 2014Antarctica is gaining ice
"What evidence is there that that tiny fractional change alters the temp at which the ocean salt water freezes or makes any discernable change to the behavior of the oceans?"
DSL:"Are you assuming that Antarctic runoff is instantly dispersed throught the world's ocean volume?"
Remember when the Malaysian airline went down in the Indian Ocean west of Australia? Remember how the surface wreckage was expected to have moved by 150 miles per day? It's called currents. .00006 over 20 years isn't much of a fraction of fresh water addition to water moving many miles per day. Most AGW arguments are based on substantial dispersion of one substance into another. When the dispersion doesn't support your ideas, sorry, you can't make it stop. Unusually high Antarctic sea ice is surrounding most of the continent across thousands of miles of sea ice perimeter. My question remains.
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Donny at 10:58 AM on 14 August 2014Antarctica is gaining ice
I also wonder if the antarctic ocean waters cool more in the summer because of a lack of sea ice. There may be too much thermal mass (as well as other variables) involved to see seasonal trends.
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Donny at 10:50 AM on 14 August 2014Antarctica is gaining ice
The problem I have with the original post (yes intermediate) is what study was used to make the leap that despite sea ice gains the thermal energy of the warming oceans make its way through the ice (which is an insulator) and causing land ice loss. Land ice loss seems more likely to come from geothermal dynamics. The authors original post would make more sense if all land ice loss was relegated to the coast. ... not sure from my readings if that is the case.
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Bob Loblaw at 10:44 AM on 14 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Tom@58, Will@62:
The geology of the last glaciation in northern Canada is rather complex, and was much-misunderstood until the late 1970s/early 1980s. There was no large single ice cap, and ice on the west side of Hudson Bay did not move out from the Bay - it moved in.
This paper does a good job of summarizing the history, and is just one of many sources of information I turned up using this Google search. Before Tom brings up my non-expert status, I'll admit to a conflict of interest: I participated in some of the relevant geological field work in the Keewatin District in 1977, when working for Bill Shilts (whose name pops up in the references of the paper linked above).
As for soil development: I have pictures (non-digital!) from the Keewatin district where it looks like the glaciers left just a short while ago. Soil development on those deposits is very, very slow in current climates. (The Keewatin District, on the western side of Husdon Bay, above 60N, is not really on our list of potential agricultural zones, though - by the time it is warm enough for agriculture, we'll all be screwed anyway.)
Continental glaciers do extensive scouring in their interiors, and deposit much glacial till in their outer regions. As they retreat, you'll expose a wide variety of till deposits, moraines, course fluvial deposits, and lake deposits where melt water is blocked from draining. Much of the final surface deposits will be the result of that final retreat stage. Many of those deposits make pretty poor soils.
In western Canada, natural drainage to the north was blocked by the retreating ice, and large glacial lakes formed. Glacial Lake Agassiz covered much of Manitoba, and Glacial Lake Regina covered a large area in southern Saskatchewan. Both created clay deposits which have a large effect on soil characteristics in those areas (as well as making the terrain as flat as last night's beer). The Clay Belt in northern Ontario also originates in Glacial Lake Ojibway. Even the history of the Great Lakes is strongly affected by the drainage patterns associated with glacial retreat.
To keep this all on topic - there is much to be considered when examining the suitability of an area for agriculture, under shifting climates. Lack of suitable soil is a serious issue (although all my direct personal experience is from a Canadian outlook).
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Donny at 10:32 AM on 14 August 2014Antarctica is gaining ice
I have. Wanted to hear your educated opinion.
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DSL at 10:22 AM on 14 August 2014Antarctica is gaining ice
And make sure you read the intermediate tab, Donny. You might also want to look at the literature on the subject.
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Bob Loblaw at 10:09 AM on 14 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Tom Curtis @56:
Thanks for digging out those additional links. Much of the information is consistent with my understanding of the geology - although I didn't download the 280MB PDF, and couldn't get a response from the matching web page.
I know there are areas of potential - I mentioned the Peace River area (N. British Columbia and Alberta) and Clay Belt (N. Ontario) earlier, and both show up in the map you provided.
As for Mills: it's not so much that I'm convinced he's wrong - he just hasn't convinced me he's right. On the basis of what is in that paper, I think the evidence is insufficient.
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Donny at 09:19 AM on 14 August 2014Antarctica is gaining ice
DSL .... is global warming and the related CO2 rise causing Antarctica to lose its land ice?
Moderator Response:[TD] Donny, you need to read the original post before commenting on this thread, so you don't waste space and everyone's time asking questions that already are answered. If you then want to ask specific questions about, or object to (with data to back you up), contentions made in the original post, please do go ahead.
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scaddenp at 09:01 AM on 14 August 2014Facts can convince conservatives about global warming – sometimes
I have responded you in the proper place. Please also read the associated article and note the plot of unadjusted data.
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scaddenp at 08:55 AM on 14 August 2014Temp record is unreliable
Replying to Donny from here.
Except that stations and practises vary worldwide and different times. Furthermore, you are claiming subjectivity when algorithms and methods are published. You asked for consistancy? What is your objection to the BEST methods? What about all the other issues? (Of which change of station is the major one?). What about UHE? Urbanization is not a uniform process?
Oh, and you can do the raw data. See above. Just that no serious researcher would try to draw conclusions from data series that are not comparable. Note also the agreement with proxies like sealevel.
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Donny at 08:13 AM on 14 August 2014Facts can convince conservatives about global warming – sometimes
Yes.
Then when the graph shows a sudden dip like it should around 1960 because of the ToD change .... we can see it graphically. It would take a certain amount of subjectivity out of the data.
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scaddenp at 07:53 AM on 14 August 2014It hasn't warmed since 1998
Donny, it appears you think that a significant part of the warming is natural? Perhaps you could tell us what data informs this opinion, given the flat or negative natural forcing data?
You would also note the increasing warming of oceans consistant with the rise in CO2 (and after all that is where most of the extra surface radiation ends up).
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scaddenp at 07:38 AM on 14 August 2014Facts can convince conservatives about global warming – sometimes
Donny, are you saying that you can make better scientific statements from temperature data that has not been adjusted for ToD, screen use, UHE, change of measuring site, etc? There are very good reasons why real studies adjust data. See "The temperature record is unreliable". Not to mention proxies like sealevel rise and ice loss.
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Donny at 07:35 AM on 14 August 2014Facts can convince conservatives about global warming – sometimes
Let me ask one more question of the accurate models. ... when will the surface temperatures begin to significantly rise again? What do they predict? Also there are so many of them. ... which one should we believe?
Moderator Response:[PS] Please put this question in the "Models are unreliable thread". Any response here will be deleted.
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Donny at 07:24 AM on 14 August 2014Facts can convince conservatives about global warming – sometimes
I agree that our temperature data encompasses such a tiny snap shot of history that making huge claims is premature. Looking at temperature trends since 1980.... 15 years would be about half that period. Not insignificant. Do you know of a study that looks at unadjusted temperature data that encompasses more than just the US and Europe? And does so with consistent methods. ..??
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DSL at 06:45 AM on 14 August 2014Facts can convince conservatives about global warming – sometimes
Donny, you really, really need to become more aware of the nature of the climate system. Using short-term surface temperature trends to make fundamental statements about the theory of anthropogenic global warming is analogous to writing a restaurant review after having had one bite of an appetizer and a glass of tap water.
Where is the bulk of the thermal capacity of the climate system?
And you also really, really need to refer to the science, instead of doing this "I believe" and "maybe" thing.
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wili at 06:13 AM on 14 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Thanks TomC. But do you have some sources to back up your claim? I know it's just a wiki site, but these are the passages from there that reinforced my crusty memory of hearing this explanation (see link above):
The current surface expression of the Shield is one of very thin soil lying on top of the bedrock, with many bare outcrops. This arrangement was caused by severe glaciation during the ice age, which covered the Shield and scraped the rock clean...
The Canadian Shield is U-shaped, but almost semi-circular, which yields an appearance of a warrior's shield, and is a subsection of the Laurentia craton signifying the area of greatest glacial impact (scraping down to bare rock) creating the thin soils...
...continental ice sheets depressed the land surface (see Hudson Bay), scooped out thousands of lake basins, and carried away much of the region's soil.
So if you have specific studies that speak against these claims, I would be most interested. Your observations are interesting, but there could be various other reasons for the distributions of soil you mention.
...Mod wrote "we wish" ;-D
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It hasn't warmed since 1998
Donny - The IPCC reports qualify the statement appropriately, but note that they have stated (AR5 SPM):
It is extremely likely [i.e. 95% confidence] that human influence has been the dominant cause of the observed warming since the mid-20th century
Various attribution studies indicate that the anthropogenic contribution is 90-170% of recent warming, with the >100% values being balanced by cooling influences of natural forcings - without which we would see even warmer temperatures.
You appear not to agree with this conclusion, which quite frankly is far beyond hypothesis status at this point. Do you have any support whatsoever for a less than dominant anthropogenic contribution? Any attribution studies, for example?
I expect not, as your posts so far have primarily consisted of arguments by assertion and out-of-context numbers that in reality don't support your positions, but I'm more than happy to be surprised.
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Rob Honeycutt at 05:35 AM on 14 August 2014It hasn't warmed since 1998
Donny... You're getting things wrong again. The IPCC states that the warming of the past 50 years is very likely primarily due to human activities. That's a very different statement. They make ample room for that to mean anything from 51% to over 100%, which they have to do because of uncertainties.
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wili at 05:33 AM on 14 August 2014Global warming is moistening the atmosphere
So how much has atmospheric water vapor increased? It seems to me I have heard figures like 6% mentioned, but I haven't seen a study that specifies this.
I also wonder how increased water vapor levels affect large weather patterns. Could it help explain the much discussed 'stuck' jetstream patterns, for example?
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Donny at 05:24 AM on 14 August 2014It hasn't warmed since 1998
CB... the IPCC alleges that of the most recent global warming ... non of it is natural and all of it is man made. ... do you agree with that hypothesis?
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CBDunkerson at 04:17 AM on 14 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Donny, there is no discrepancy in need of justification. Warming over the past ten years has been in line with predictions.
I suspect you are talking about 'lower atmosphere warming', which has been relatively low the past ten years. However, as that represents only about 2% of the total warming it isn't remotely representative. If you look at the full picture (mostly the oceans) then warming has continued unabated. You can get basic info on this at;
http://www.skepticalscience.com/global-warming-stopped-in-1998.htm
Moderator Response:[TD] Donny, if you want to respond to this comment, do so on that other thread that CB linked. Everyone else, likewise.
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Donny at 04:10 AM on 14 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
CB Dunkerson.... the overwhelming evidence is all tied to one fact that CO2 drives global temperature. ... which I believe it does. ... however maybe on a much smaller scale than is hypothesized. Ten years ago I expected much more warming than we have seen despite continuing to dump record amounts of CO2 into the atmosphere. How do you justify that discrepancy in your mind?
Moderator Response:[TD] That topic is relevant to the Models Are Unreliable thread. Take the conversation there. Or to the Increasing CO2 Has Little to No Effect thread
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Donny at 03:59 AM on 14 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Ma Rodger@ 54.... those figures were not mine. They were from Scaddenps references I believe. There are different deficiencies that can add to a soil not being suitable for agriculture. .. some like pH can be remedied very quickly. I believe we should stop using fossil fuels not because of the CO2 as much as the fact that we are using up a resource that is not going to last forever.
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r.pauli at 23:50 PM on 13 August 2014New study finds fringe global warming contrarians get disproportionate media attention
Mass media news has to know that it is playing a risky game of gambling with public trust. Once audiences discover that their news sources are misperceiving or misleading, then viewers will seek trusted information elsewhere. Specialized web sites, apps, and online videos are vastly superior to TV or newspapers,,,and it suggests the rise of targeted subject matter news - like business reports shows. We are ready for a half hour daily global warming show. (straightforward to gather up an hours worth of climate news per day) The audience is there, waiting for it, ill served by mass media. Weather calamities will trigger the cognitive dissonence that might push the change. Mass media news that provides 2 minutes of pictures and grieving victims will be left to compete amongst themselves.
In a recent lecture Prof Kerry Emanuel of MIT mentioned the problem that media faces in business practices that drive it to false debating An excellent lecture.
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johncl at 23:14 PM on 13 August 2014New study finds fringe global warming contrarians get disproportionate media attention
Bob, interestingly the right-wing media have a tendency to call in the same scientist all the time, so perfectly ridiculed by John Oliver - Bill Nye vs some climate sceptic. For the viewers it portrays the climate debate as one single guy against many others who are "skeptical".
A tactic that climate scientists could use is to form a PR agency where they will provide the media with an expert best equipped to answer the question in discussion, and by this also give a more correct view of the overwhelming amount of scientists that say AGW is real and a present danger. Even the left-leaning media outlets would benefit from this as they also have a tendency to air the same handful of scientists. In some panels it would be wise to have more than one scientist too, so people can see how they agree about AGW too although through studying different fields.
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Dikran Marsupial at 17:21 PM on 13 August 20142nd law of thermodynamics contradicts greenhouse theory
MattJ I think you are missing the key point which is that the net transfer of heat is from the warmer surface to the cooler atmosphere, so the second law of thermodynamics holds whether there is "some other change" or not. If you lie under a blanket, the blanket keeps you warmer than you would otherwise be, even though the blanket (and the air beneath it) is cooler than you are. This does not require "some other change" in the blanket (or air beneath it) and does not contravene the second law of thermodynamics.
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rkrolph at 16:39 PM on 13 August 2014Survey confirms scientific consensus on human-caused global warming
From the pdf link to the list of survey questions, only question 1 mentions "human induced". But for question 1, there is a part a and part b, each with multiple choices. So I am confused about what exactly the answers were that determined the red bars in figure 2. Because even for AR4 authors, there is less than 80% agreement (red bar) for question 1. Could someone please clarify? Thanks.
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Tom Curtis at 16:12 PM on 13 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
wili @57, the idea that soils under previous continental ice sheets are poor because the area was "scraped clean" or "scraped back to bedrock" does not stand up to scrutiny. In particular, the key feature of continental ice sheets is that they are formed in situ by snow failing to melt in the summer. There is some motion of the ice, due to pancaking as areas of higher snow deposition build up to great altitudes but that motion is limited in extent. Areas directly under centers of motion will experience almost not lateral movement. At the edge of the ice sheet, lateral movement will be greater but not scour deep as the ice sheet will only be tens of meter, not thousands of meters thick at those locations. (The situation is quite different, of course, for mountain glaciers.)
Further, the notion that the regions of poor soil in Canada were "scraped clean" does not stand up to compasison of soil types. The very good soils of the Canadian Prairie were covered by a continental ice sheet up until eleven thousand years ago, with the best soil covered the longest:
No Canadian soils on the mainland were covered by ice sheets after eight thousand years ago, so if that were the limiting factor there has been plenty of time to reestablish soils of some variety, even if not suitable agriculture. Further, if "being scraped back to the bedrock" were the problem, regosols would be common throuhout Canada. Instead they are rare. They are dominant in only limited regions (as can be seen by playing around with the Soils of Canda map.
Consequently, I would conclude that the major factors limiting soil quality in Candada have been large areas of poor drainage, particularly south of Hudson bay, large regions were cold climates make them unsuitable for grasslands but suitable for forests, and even larger regions in which the formation of permafrost limits the development of soils.
Finally, glaciation was very extensive in Alaska in the last glaciation, albeit not in the Yukon valley and delta formation.
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wili at 13:24 PM on 13 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Tom, I think the wider range of soils in Alaska has more to do with the fact that it mostly wasn't scraped clean by glaciers in the last ice age. http://mapsof.net/map/north-america-glaciation-map#.U-rZu0jz2B0
Moderator Response:[PS] Fixed link. Please learn how to do this yourself with the link button in the editor.
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MattJ at 11:30 AM on 13 August 20142nd law of thermodynamics contradicts greenhouse theory
This is a good post, but I would like to believe that a lot of the thrashing in the discussions attached to it could have been avoided if Skeptical Science would edit the article to make the correction already suggested by post#955: the citation of the Clausius formulation of the Second Law is incorrect.
Far better would be to use Clausius's own translation of his statement of the law: "Heat can never pass from a colder to a warmer body without some other change, connected therewith, occurring at the same time."
One of the immediate advantages of this formulation is that it immediately enables us to put the burden on the "believers in the imaginary Second Law" to show that there are no "other changes" that allow the transfer of heat from the cold atmophere to the warm earth.
Certainly, the 'generally' of the version currently in the article is terribly confusing. What is 'generally' supposed to mean in the statement of a physical law? Would Newton ever have said "to each and every action there is generally an equal and opposite reaction"? Of course not.
At least when Clausis said "other changes", we know he was speaking in the context of heat engines, so we know he meant changes in thermodynamic state, whether of the heat engine or in the surrounding environment. We do not know anything of the sort for 'generally'.
Alternatively, several great physicists of more recent times, so in reference to the more complete theory of thermodynamics they themselves developed, have given formulations that might even prove more useful, e.g.:
Wolfgang Pauli: Clausius says that heat conduction is an irreversible
process — a process is called irreversible if the initial state
cannot be reached from the final state without compensationEnrico Fermi: it is impossible to have a process whose SOLE effect is
the transfer of heat from a colder to a hotter bodyRichard Feynman: Carnot asserted that at constant temperature it is
impossible to extract heat out of its source and turn it into work,
without producing other changes in the given system or its surrounding
environment.Please consider these also, but at the very least, correct the Clausius quote: it can only cause unnecessary confusion, as people are still referring to this article.
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Tom Curtis at 10:47 AM on 13 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Bob Loblaw @47, your first link is indeed the map I was indicating. I have since found a more suitable map (the third map from this site to which you have previously linked), as it shows the actual soil qualities. Of particular interest in your dispute with Donny is the large swathes of soil in the east of Canada which have "No Capability for arable culture or permanent pasture" (pink) despite being at the same latitude as the Canadian prairies, and hence are not restricted by climate factors.
Equally interesting are the areas of arable land (some of the highest quality) along the Peace river (north west Alberta) and the single mapped section in north east British Columbia showing a complex interlacing of arable soils (brown) adjacent to a large section of peats (black) which are unsuitable for agriculture. The high latitude of these sections relative to the northern limit of the Canadian prairies shows that northern limit to have been set by soil type rather than climate.
Those examples, however, also show where, and how we can expect to find suitable soils in Northern Canada with increased global warming. Both represent deposits of river silt, a process that produces suitable soil for agriculture almost regardless of climate (ie, soil in which agriculture is only restricted by climate). There presence indicates that such suitable soils are also likely to be found in the river valleys of the MacKenzie and other smaller northern rivers descending from the Rockies. Comparison with the soil map of a Canada (first map, previously linked site) does show the relevant reaches of the McKenzie have luvisolic soils, and thus they are likely to provide small regions of class three or four soils (as with BC reaches of the Peace, which has a similar soil classification). That is, the land will be potentially arable, but will require extensive conditioning to control soil pH (if I understand the description correctly).
As an aside, a more detailed soil map of Canada, and indeed of Siberia as well, can be found in the "Soil Atlas of the Northern Polar Region" (280 MB PDF; website). Unfortunately the basis of classification in that atlas does not lead directly to an ability to classify as to whether or not the soil is arable, at least for inexpert commentors like me.
With regard to Mills (1994), closer reading shows that he finds 16 million Hectares of arable land that would be opened up from a doubling of CO2, but that the majority (15.9 million Hectares) of that will be in Alaska, while only 0.2 million hectares will be within the study area within Canada itself (page 122). The study area within Canada is quite restricted (fig 1), so that some more might be expected in Canada, but arguably not a lot as the most suitable sites on geographical grounds are also the most likely to have been surveyed. This difference between Alaska and Canada is consistent with the hypothesis above that river valleys will produce arable land even in climates currently to cold to sustain cropping, along with the size of the Yukon river valley.
I am not sure if this additional information reconciles you to the Mills (1994) results, but regardless I will accept the result of a peer reviewed study over the anecdotal evidence of a non-expert 100% of the time. If you think Mills is wrong, find a more recent peer reviewed study showing that he is wrong.
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dcpetterson at 08:25 AM on 13 August 20141934 - hottest year on record
It may be worth noting, 1934 was also the first year of te Dust Bowl, a human-asued natural disaster in the American Southwest. It seems likely the exteme heat in the continental US that year was, in some part, due to the destruction of grasslands and the immense dust storms. Barren land absorbs more heat than grasslands do.
Pointing out how hot 1934 was in the contiental US is a good way to stress the adverse effects of human activity on the climate and the weather.
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Bob Loblaw at 07:31 AM on 13 August 2014New study finds fringe global warming contrarians get disproportionate media attention
An interesting thought about how this could potentially play out. Given a large pool of climate scientists for the "97%" side, the media could easily pick a different expert for each story - especially if they try to pick an expert with particular knowledge, eg., hurricanes, or the arctic, or El NIno.
On the other hand, the "3%" side has a few go-to contrarians, who get called upon frequently, whether the sotry is in their area of "expertise" or not.
In the public's eye, the "97%" story is seen as a different face each time, and the "3%" story is represented by an increasingly familiar face. Some people might start to think that the person they see time after time is the "real" expert, and all the others are just drive-by wannabes. After all, why would the media keep going to the same person if they aren't the best? (Yes, that's a rhetorical question. The answer is "false balance".)
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wili at 04:57 AM on 13 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
From a few months ago at http://thinkprogress.org/climate/2014/03/07/3370481/california-drought/
"… scientists a decade ago not only predicted the loss of Arctic ice would dry out California, they also precisely predicted the specific, unprecedented change in the jet stream that has in fact caused the unprecedented nature of the California drought. Study co-author, Prof. Lisa Sloan, told me last week that, 'I think the actual situation in the next few decades could be even more dire that our study suggested.'"
(Thanks to hank at RC for this quote and link.)
(I have concluded that 'donny' is a sockpuppet of one of the mods trying to yank our collective chains--good one, guys!)
Moderator Response:[PS] fixed link ... and we wish....
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MA Rodger at 02:14 AM on 13 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Donny @52.
Surely the reason why you "still (are) skeptical about the reliability of using the models to predict the climate" is mainly because you still consider the "case with global warming" to be "nature ... behaving a certain way." That is, you are simply in denial over AGW, and that is despite your studies in Environmental Biology.
Concerning the topic of discussion you presently find yourself engaged in here - the impact of future AGW on agricultural output - from your studies you should know that primary succession requires a lot of time for soil formation. Thus where soils are presently inadequate for agriculture, any profound allogenic change due to AGW that acts over just a few decades will not alter the agricultural usefulness of soil, unless perhaps we take up farming lichen & moss (yum yum!!).
But, hey, @50 you seem to be saying that a landscape free of glaciation for around 12,000 years will result in soils with which "we shouldn't have much of a problem." Now, I say "seems to be saying" as I am but positing the idea that this isn't another instance of Donny "responding flippantly." It may well be otherwise as even when glacier-free for many millennia, the lands north of Canada's prairies are not renowned for deep soil cover.
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MA Rodger at 02:07 AM on 13 August 2014Error identified in satellite record may have overestimated Antarctic sea ice expansion
Assuming, then that it does make sense @20, that leaves BojanD's "enigma" @16 - Why didn't anybody notice the inadvertent error-&-fix? Weren't all the "other researchers" paying attention?
The IPCC AR4 & AR5 are the two accounts that Eisenman is pointing to as presenting Antarctic trends without noticing. But they don't appear to present these trend figures as being very important.That is AR4 WG1 Section 4.4.2 doesn't do a great job on describing this trend. 4.4.2.2 says regarding both poles "Different estimates, obtained using different retrieval algorithms, produce very similar results for hemispheric extent" but AR4 is here more concerned with the difference between the Arctic & Antarctic trends than with the level of that 'similarity of result' from the different algorithms when applied to Antarctica. Thus it presents for both poles only the Cosimo data (what we are calling here the BootstrapV1) with the trend from the data to 2005 described "the antarctic results show a small positive trend of 5.6 ± 9.2 × 103 km2 yr–1 (0.47 ± 0.8% per decade), which is not statistically significant ... (at) 90% confidence". What AR4 describes as a "similar result" would include the NASA Team data that I calculate as having a 1979-2005 trend of 13.4 ± 10.0 × 103 km2 yr–1. (pretty much the same as Eisenman et al (2014) fig S6D shows).
However, AR4 provides here no more than a short account with the take-away being the difference between Arctic & Antarctic rather than the nailing of the Antarctic average trend.AR5 WG1 Section 4.2.3.1 again presents only the Cosimo trend (now the BootstrapV2 trend) but then turns to discuss seasonal trends, and within FAQ 4.1 reasons for the Antarctic trend and the regional differences within the Antarctic.
However both within AR5 WG1 Suplementary Material Section 4.SM.1 (where our BootstrapV1 is given the acronym SBA and our NASA Team is called NT1) and within Eisenman et al (2014) Supplimenatary Discussion & Figures there is surely ample detail to drown any thought of "enigma" concerning the unnoticed change in trend from using BootstrapV1 to BootstrapV2. There is so much more other stuff going on. -
DSL at 01:08 AM on 13 August 2014Antarctica is gaining ice
jetfuel: "What evidence is there that that tiny fractional change alters the temp at which the ocean salt water freezes or makes any discernable change to the behavior of the oceans?"
Are you assuming that Antarctic runoff is instantly dispersed throught the world's ocean volume?
Jetfuel: "If a larger amount of temporary lake ice gain is unimportant, how is that amount (81 GT) of loss important?"
This is almost identical to the "temp changes by 15-20C over the course of year in some places; therefore, getting worked up over 0.7C in fifty years is ridiculous" argument. The thing is, Antarctic land ice loss will continue and accelerate as glacial terminators erode more and more quickly. Antarctic land ice won't reach equilibrium with global climate for hundreds if not thousands of years.
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jetfuel at 23:37 PM on 12 August 2014Antarctica is gaining ice
The twenty year cumulative 1620 GT loss of Antarctic Land Ice, when compared to the 26450000 GT on Antarctica is .00006 or .000003 per year on avg. as a fraction. Since 97% of all water is ocean water, and Antarctica holds 61% of all fresh water, all those 20 years of melt together have dilluted the oceans by .0000010 as a fractional addition of fresh to salt water. What evidence is there that that tiny fractional change alters the temp at which the ocean salt water freezes or makes any discernable change to the behavior of the oceans? How could a large percent of the 81 Gt of net melt per year exposing rock? The ice is 8200 feet thick even on the penninsula. As far as am I serious, I was comparing to the seasonal N.A. lake ice because 81 out of 26.45 million gigatonnes isn't an appreciative amount of loss. If a larger amount of temporary lake ice gain is unimportant, how is that amount (81 GT) of loss important?
Moderator Response:[JH] Please document the sources of the data that you have used in the above post.
You have a history of posting comments like the above without providing any citations. You have been repeatedly asked to provide documentation. For the most part, you have ignored these requests. If you continue this pattern of behavior, you will relinquish your privalege of posting on this website.
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Composer99 at 23:34 PM on 12 August 2014Antarctica is gaining ice
jetfuel is IMO grasping at straws, and has been for some time.
Although that's really all that needs be said, I should add that jetfuel is trying to compare cumulative year-over-year land ice mass loss in Antarctica with (cyclical) seasonal river/lake ice volume gain in Canada - and ignoring the inevitable melt-away of the latter.
At best, maybe jetfuel would be on to something if the change in seasonal ice/snow cover in Canada is measurably altering the albedo, as scaddenp notes, but I doubt we'll see jetfuel come up with any evidence showing the existence or magnitude of such an effect.
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CBDunkerson at 21:46 PM on 12 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Donny wrote: "...I still am skeptical about the reliability of using the models to predict the climate."
So don't.
Ignore the models. Look at analyses of past climate changes. Or the measured impacts of the current ongoing climate change. Or the pure physics calculations of the effects of increasing greenhouse gases and directly linked feedbacks.
These all point to the same general conclusions as the models. The primary benefit of the models is in allowing us to estimate different future scenarios based on our actions in the upcoming decades. Some are also starting to provide reasonable estimates of regional, rather than global, impacts. However, if we tossed the models out entirely all available evidence would still be indicating that the rapid CO2 increase we have introduced is causing the rapid warming we are observing.
You don't need models to predict the climate. Arrhenius successfully predicted many of the climate changes which have now taken place all the way back in the 1890s... decades before modern computers, let alone climate models, even existed.
'Models aren't perfect' is true, but generally a poor excuse for ignoring them. However, as an excuse for ignoring the over-whelming evidence that has nothing to do with models it is just plain illogical.
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CBDunkerson at 21:26 PM on 12 August 2014Antarctica is gaining ice
jetfuel, setting aside the different effects of ice in different locations outlined by scaddenp... you are also comparing the antarctic annual volume loss rate to (vague generalizations of) the Canadian annual volume maximum. That is obviously illogical.
That 81 GT average was over the period 1992 - 2011... twenty years. So the total ice loss for that period was ~1,620 GT. Meanwhile, the total annual ice gain in Canadian lakes over the same period was, what? Approximately zero? In Summer they are melted out so we've gone from zero ice volume to zero ice volume. In winter they freeze to varying extents, but setting aside the one anomalous year you cite, the overall trend has likely been decreasing ice volume. In any case, any changes in average volume over the course of the year have been minimal compared to the Antarctic ice loss.
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scaddenp at 14:03 PM on 12 August 2014Antarctica is gaining ice
Are you serious? Let's suppose say that Canada's lakes gain and lose say 1000Gt of ice between summer and winter. Only a change in the surface area of lakes frozen or a change in timing (which would both affect earth albedo) would have any climate significance. On the other hand, 81Gt of ice loss from Antarctica is going straight into sealevel rise. Furthermore, as rock is exposed albedo is reduced.
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jetfuel at 13:43 PM on 12 August 2014Antarctica is gaining ice
Shepherd et al. (2012) estimate the mass balance of the entire Antarctic Ice Sheet to be -81 ± 37 gigatonnes per year. The tolerance band is less than Lake Superior's 2014 ice volume change when 2 feet thick ice formed over the 32 thousand square mile lake. Canada has over 320 thousand square miles of lakes that get ice each winter. Antarctica's 81 GT loss per year may not be much when compared to the millions of GT there.
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Donny at 13:31 PM on 12 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Michael. ... when someone is trying to justify why nature is behaving a certain way as is the case with global warming it can be very blinding to get caught up in the minutia of individual studies especially when studies conflict each other. I have read hundreds of climate studies over the years. I have a degree in environmental biology so I know a thing or two about succession. You asked me why I believed that the climate models were inaccurate and I provided 2 different studies for you. I don't think that the models are useless. ... I agree that they can help us continue to refine the complex mechanisms that dictate climate. However no matter how much you insult or belittle me I still am skeptical about the reliability of using the models to predict the climate. But if it makes you feel smarter to belittle me.... go ahead.
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Donny at 13:12 PM on 12 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Let's also not forget that if it came down to it we can stop using corn to make fuel.
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Donny at 13:09 PM on 12 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Ok.... so let's discuss what we have learned. We know from Scaddenps second reference @48 that soils take different amounts of time to develop. We also know that temperature and moisture also affect the rate. In Wisconsin the soil took 8000 years to develop. So since we know that the glaciers retreated from Southern Canada around 12000 years ago. ... we shouldn't have much of a problem.
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michael sweet at 12:43 PM on 12 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Donny,
In this exchange we see the difference between skeptical sites like WUWT and scientific sites like SkS. When you challenged Scaddenp on the age of soils he produced (very strong) evidence tht soils are indeed very old. You have provided no evidence to support your position that soils can change in a human lifetime, although you have been asked for such evidence. At WUWT they rarely provide evidence, they argue by assertion, as you have done. Scientists argue by producing evidence to support their claims. I am more likely to believe Scaddenp the next time he comments because he has provided data that supports his claims.
The ball is now in your court. You can do one of two things:
1) Conceed that Scaddenp was correct and that you have learned something.
2) Produce evidence that supports your claims.
I do not need to challenge Scaddenp since I also knew that soils take thousands of years to develop.
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Stephen Baines at 08:07 AM on 12 August 2014Facts can convince conservatives about global warming – sometimes
Carbtheory. It is a scientist's job to critically evaluate evidence in support of propositions. They are hired and promoted largely based on the ability to do just that. So it is not that much of a stretch to believe that many of them do in fact have the time to evaluate evidence thoroughly, especially in their specialty.
As for those denying the consensus, they would seem to fall just as easily into category 4 of your system — The alienated. Frankly, Im not sure that label is constructive either. Contrary voices play an important role in science generally, even though they are most often wrong — it's just that in this case those voices are amplified to such a degree that the general consensus among climate scientists is not apparent to the general public.
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scaddenp at 07:43 AM on 12 August 2014Air pollution and climate change could mean 50% more people going hungry by 2050, new study finds
Well I am very surprised that someone thinks the slow pace of soil development is wild claim, when a google of "how long soil develop" would give you the textbook answers, but least I be accused of making unstantiated claims, then this well-cited study on post-glacial vegetation recovery is useful and there is this online University of Minnesota textbook
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