by Judith Curry
A few things that have caught my eye over the past few weeks.
More on Extreme Weather
Andy Revkin has an article ‘More on Extreme Weather in a Warming Climate.’ It refers to a Nature Climate Change perspective by Coumou and Rahmstorf, with the following (predictable) abstract:
The ostensibly large number of recent extreme weather events has triggered intensive discussions, both in- and outside the scientific community, on whether they are related to global warming. Here, we review the evidence and argue that for some types of extreme — notably heatwaves, but also precipitation extremes — there is now strong evidence linking specific events or an increase in their numbers to the human influence on climate. For other types of extreme, such as storms, the available evidence is less conclusive, but based on observed trends and basic physical concepts it is nevertheless plausible to expect an increase.
Revkin’s article is worth reading for the comments from Martin Hoerling and Mike Wallace. From Martin Hoerling:
– Very few of the [cases of extreme weather listed in the paper] have undergone a scientific investigation of contributing factors, let alone human impacts. The fact is that extremes happen, have happened, and will continue to happen. For some, their character, preferred phase, and intensity may be changing (aside from temperature extremes, the detection and attribution evidence to date is weak).
– I suspect that if one engaged in grand mitigation today (as useful as that would be for many other purposes), many of the extremes listed in [the paper] would happen anyway, and will likely happen again.
– The matter of attribution, as raised in the second to last paragraph, is a much broader science that merely determining the change in probability due to greenhouse-gas forcing….which is an inherently difficult and uncertain undertaking. The piece ignores the broader context in which all manner of contributing factors is assessed to understand the magnitude of events, their temporal and regional specificity (e.g., why did the heat wave happen over Texas (rather than Washington), why did it occur in 2011 (and not 2009, or next year), and why did it break the previous records by a factor of 2. After all, the irony of extreme events is that the larger the magnitude the smaller the fractional contribution by human climate change.
– The piece often convoluting apparent “effects” of apparent changes in extremes in the last decade with causes not to arise till the latter part of the 21st century.
From Mike Wallace:
By exaggerating the influence of climate change on today’s weather and climate-related extreme events, a part of our community is painting itself into a rhetorical corner.
My opinion piece, “Weather and Climate-Related Extreme Events: Teachable Moments ” [link; go to the bottom of the page] to which Hoerling refers, serves as a counterpoint to Coumou and Rahmsdorf’s article. Before submitting it to Eos, as an experiment, I submitted it to Nature: Climate Change, where their article was published. I cannot say that I was surprised when the editors informed me that they would not be sending it out for review because “we are not persuaded that your article represents a sufficiently substantial contribution to the ‘climate change debate’ [my quotation marks] to justify publication in the journal”. Perhaps to ease the pain of rejection, the editor added, “more Commentaries are actively commissioned and […] we only rarely publish unsolicited contributions to the section”.
Although it may sound a bit like sour grapes, here’s the way that I’ve rationalized Nature’s editorial decision. I’ve become convinced that many of the editors of the high impact journals are inclined to cast opinion pieces as salvos in the ongoing war between climate change believers and skeptics. Articles like mine that take issue with the way in which the war is being waged are not particularly welcome. By soliciting opinion pieces and by selecting, from among the growing list of contributed articles, the very few that will be sent out for peer review, the editors promote their vision of what constitutes “groundbreaking” and “policy relevant” science. What if it is not the right vision?
By granting the editors of Nature and other high impact journals ever increasing power in deciding which of our articles should be singled out for emphasis in the news media, we risk losing control of the peer review process upon which our public image depends. The way to maintain control is to make a point of sending our most newsworthy scientific articles and opinion pieces to the journals of our own professional societies, in which the peer review process is editor-facilitated, rather than editor-directed. Dot.Earth could render our community a valuable service by ensuring that newsworthy articles published in our journals receive the public attention that they deserve.
JC comment: Bravo, Marty and Mike!
Tobis on disequilibrium
Michael Tobis has an interesting article, also referenced in Revkin’s piece. The title is Disequilibrium is not your friend. The key statement that caught my interest:
As applied to the climate system, consider it a plausibility argument: the more rapidly and extensively the system is disturbed, the more we would expect that unexpected behaviors will emerge, and the further from expectations they will be.
If this is the case, you cannot simply add “global warming” and “natural variability”. (Formally, arguments “from superposition” do not apply.) If a place is ten degrees above normal at a time of one degree of global warming, it does not make sense to say that one degree is due to climate change, and nine degrees “would have happened anyway”, even in a statistical sense. It implies that the dynamics of the system are the same under perturbation. Is that a realistic presumption in the absence of other evidence? I think it shows a weak understanding of general systems principles to make that case.
He then goes on to cite results from a new paper by Hansen.
JC comment: This is a topic that is well worth discussing. The nature of the extreme events depends on what kind of a regime you land in, after the climate shift. The general approach used by Hansen is worth critiquing and developing further, but how to interpret this kind of analysis in the context of attribution isn’t clear. I would take the longer time series (e.g. western Europe esp CET and eastern U.S.) and interpret the distribution of extremes in the context of a regional climate dynamics analysis.
(Un) common sense from ThinkProgress
At ThinkProgress, the former dominance of Joe Romm on climate issues is becoming increasingly diluted. See this guest post entitled Nine Low-Tech Steps For Community Resilience in a Warming Climate. Good suggestions.
In the not to be believed department, at Scott Mandia’s blog he has a post Support Climate Scientists and Look Cool Doing So!
Help the Climate Science Legal Defense Fund (CSLDF) raise money to cover the costs of Dr. Mann’s legal defense as well as other scientists who face similar challenges. To help raise money and reward those that contribute, we have rounded up some cool designs and gifts. CSLDF thanks Nicole Martinez and Lunchbreath who were kind enough to donate their designs for this fundraiser.
- $25 gets you one of our t-shirts. They will be delivered a couple weeks after the fundraiser is over. We will check in with you about which design you want and what size.
- $50 gets two of the t-shirts.
- $75 gets all three of the t-shirts and our true gratitude.
- $150 gets you all three of the t-shirts and a copy of Climate Change: Picturing the Science signed by Joshua Wolfe (www.picturingclimatechange.com)
- $300 gets you a hockey stick signed by Mike Mann.
- $1000 gets you a 16×20 signed silver gelatin print by Joshua Wolfe.
I wonder how many hockey sticks have been sold.