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An Emerging View on Early Land Use

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Guest article by William Ruddiman

More than 20 years ago, analyses of greenhouse gas concentrations in ice cores showed that downward trends in CO2 and CH4 that had begun near 10,000 years ago subsequently reversed direction and rose steadily during the last several thousand years. Competing explanations for these increases have invoked either natural changes or anthropogenic emissions. Reasonably convincing evidence for and against both causes has been put forward, and the debate has continued for almost a decade. Figure 1 summarizes these different views.

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Rescuing data…

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Guest commentary by Vicky Slonosky

One of the lesser-known branches of climatology is historical climatology, the study of past climates from historical records of instrumental observations and weather descriptions, with “historical” often loosely taken to mean “pre-government-organized-meteorological or weather service” observations. In the last ten years or so, with the development of digital imaging, increased storage and processing capabilities of computers, it’s become possible to think about analyzing these past records on a daily basis. Snowstorms, hurricanes, cold snaps or heat waves all happen on daily scales, and daily information over the past 200 years or more let us learn more about them. All over the world, efforts (many unfunded) are going on to try to find and preserve these historical data from personal weather diaries, scientific observatories and naval records. This is often described as “data archeology and rescue”, which has a nice ring to it, and even manages to make going through dusty boxes in dustier basements and typing in the original (often handwritten) observations sound glamorous and exciting. It’s not a simple task though:

“All my attention for recent years has been directed to that branch of meteorology connected with ascertaining the mean temperature of Lower Canada. I had not made up my mind as to the fact of the climate having materially altered but was impressed generally with the belief that the climate had improved, or become warmer, as it had increased in population and cultivation … I resolved to make diligent search for such records as might be found in the Province, in order to answer this interesting question. The difficulty of this experience was even greater than I had anticipated. Few individuals had turned their attention to this (even now) infant science, at a period sufficiently removed to bear comparison with the present, and of those which I was fortunate enough to discover, many were unsuitable from the irregular manner in which they were kept … None but the most zealous meteorologist knows how very difficult it is to obtain observations in this science which can be depended upon.”

John Samuel McCord, acc. 0882, McCord Museum of Canadian History Archives, circa 1838.

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Making climate science more useful

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Impression from the ICTPLast week, there was a CORDEX workshop on regional climate modelling at International Centre for Theoretical Physics (ICTP), near Trieste, Italy.

The CORDEX initiative, as the abbreviation ‘COordinated Regional climate Downscaling Experiment‘ suggests, tries to bring together the community of regional climate modellers. At least, this initiative has got a blessing from the World Climate Research Programme WCRP.

I think the most important take-home message from the workshop is that the stake holders and end users of climate information should not look at just one simulation from global climate models, or just one downscaling method. This is very much in agreement with the recommendations from the IPCC Good Practice Guidance Paper. The main reason for this is the degree of uncertainties involved in regional climate modelling, as discussed in a previous post.

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Friday round-up

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Last week, Nature published another strong statement addressing the political/economic attack on climate science in an editorial titled “Into Ignorance“. It specifically criticized the right wing element of the U.S. Congress that is attempting to initiate legislation that would strip the US EPA of its powers to regulate greenhouse gases as pollutants. In so doing, it cited as an example the charade of a hearing conducted recently, including the Republicans’ disrespectful and ignorant attitude toward the science and scientists. Among many low points, this may have reached its nadir when a House member from Nebraska asked, smirkingly and out of the blue, whether nitrogen should be banned–presumably to make the point that atmospheric gases are all either harmless or outright beneficial, and hence, should not be regulated. Aside from the obvious difference that humans are not altering the nitrogen concentration of the atmosphere, as they are with (several) greenhouse gases, such a question boggles the mind in terms of the mindset that must exist to ask it in a public congressional hearing in the first place. But rarely are the ignorant and ideological bashful about showing it, regardless of who might be listening. In fact an increasing number seem to take it as a badge of honor.

There have been even more strongly worded editorials in the scientific literature recently as well. Trevors and Saier (2011)*, in a journal with a strong tradition of stating exactly where it stands with respect to public policy decisions and their effect on the environment, pull no punches in a recent editorial, describing the numerous societal problems caused when those with the limited perspective and biases born of a narrow economic outlook on the world, get control. These include the losses of critical thinking skills, social/community ethics, and the subsequent wise decision making and planning skills that lead a society to long-term health and stability.

Meanwhile, scientific bodies charged with understanding how the world actually works–instead of how they would imagine and proclaim it to–continue to issue official statements endorsing the consensus view that humans are strongly warming the planet in recent decades, primarily by greenhouse gas emissions to the atmosphere. Three years ago, we wondered whether geologists in general have a different view on climate change to the climate research community. A recent statement from the U.K. Geological Society, however, suggests that our impressions perhaps were not well-founded.

Notwithstanding these choices of ignorance, many other organizations continue apace with many worthwhile and diverse goals of how to deal with the problem. Here are a few links that we have run across in the last week or two that may be of interest to those interested in sustainability and adaptation. Please note the imminent deadlines on some of these.

The Center for Sustainable Development’s online courses related to community-level adaptation to climate change:

The CDKN International Research Call on Climate Compatible Development:

The Climate Frontlines call for abstracts for a July conference in Mexico City on the theme “Indigenous Peoples, Marginalized Populations and Climate Change” [Apologies: the official deadline for abstracts has apparently passed; view this is a conference announcement]

George Mason University’s call for votes on the Climate Change Communicator of the Year

*Trevors, J.T & Saier Jr., M.H. 2011. A vaccine against ignorance? Water, Air and Soil Pollution, DOI 10.1007/s11270-011-0773-1.

Blogging climate scientists

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The newest arrival in the climate science blogosphere is Isaac Held. This is notable in a number of respects. First, Isaac is a top-tier climate scientist who is hugely respected in the community. For him to decide that it is worth his time to blog on the science should be an important signal for other scientists. Secondly, Isaac is a federal NOAA employee at GFDL in Princeton, and the blog is on the official GFDL website.

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Under and over the ice

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I really like the fact that there is still so much to discover about important parts of the climate system. The Bell et al paper in Science Express this week (final version in Science) reporting on the surprising results from airborne ground-penetrating radar studies of the Antarctic Ice Sheet is a great example. The ice sheets themselves are the biggest challenge for climate modelling since we don’t have direct evidence of the many of the key processes that occur at the ice sheet base (for obvious reasons), nor even of what the topography or conditions are at the base itself. And of course, the future fate of the ice sheets and how they will dynamically respond to climate warming is hugely important for projections of sea level rise and polar hydrology. The fact that ice sheets will respond to warming is not in doubt (note the 4-6 m sea level rise during the last interglacial), but the speed at which that might happen is highly uncertain, though the other story this week shows it is ongoing.

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Wahl-to-Wahl coverage

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Eugene Wahl asked us to post a statement related to some incorrect claims circulating in the blogosphere:

The Daily Caller blog yesterday contained an inaccurate story regarding a correspondence that was part of the emails hacked from East Anglia University Climate Research Unit (CRU) in November 2009.

For the record, while I received the email from CRU as forwarded by Dr. Mann, the forwarded message came without any additional comment from Dr. Mann; there was no request from him to delete emails. At the time of the email in May 2008, I was employed by Alfred University, New York. I became a NOAA employee in August 2008.

The emails I deleted while a university employee are the correspondence I had with Dr. Briffa of CRU regarding the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, all of which have been in the public domain since the CRU hack in November 2009. This correspondence has been extensively examined and no misconduct found. As a NOAA employee, I follow agency record retention policies and associated guidance from information technology staff.

Dr. Eugene R. Wahl

March 9, 2011

Further questions can be addressed to Katy.G.Human -at- noaa.gov

Our comments

These claims are simply the latest attempt to try and manufacture scandals and smear scientists, particularly Mike Mann, based on the UEA emails. The story appears likely to have come from Senator Inhofe’s office who presumably had access to the transcripts taken by the NOAA Office of the Inspector General (whose investigation found no evidence of any wrongdoing by NOAA employees). The story was planted with Steve McIntyre, Anthony Watts, and Chris Horner, and then linked to by Inhofe’s office to provide a little plausible denialability – a rather blatant media spin operation.

But the facts of the case do not support the narrative they are pushing at all. While Jones’ original email was certainly ill-advised (as we stated immediately it came to light in Nov. 2009). Eugene Wahl was not subject to FOIA at the time (since he was not a federal employee) and was not subject to UK FOI anyway since he was working for a US-based university. Nor was he aware of any ongoing FOI actions in any case. In the original emails released, Mann stated that he would notify Wahl of Jones’ email, and his only involvement was to forward the Jones email to Wahl which Wahl’s account confirms.

So what is the actual issue at the heart of this? A single line in the IPCC AR4 report (p466) which correctly stated that “Wahl and Ammann (2006) also show that the impact [of the McIntyre and McKitirck critique] on the amplitude of the final reconstruction [by MBH98] was small (~0.05C)”. This was (and remains) true. During the drafting Keith Briffa corresponded with Eugene Wahl and others to ensure that the final text was accurate (which it was). Claims from McIntyre that this was not allowed under IPCC rules are just bogus – IPCC authors can consult with anyone they like at any time. However, this single line, whose inclusion made no effective difference to the IPCC presentation, nonetheless has driven continuing harassment of everyone involved for no good purpose whatsoever. Wahl and Ammann did show that MM05 made no substantial difference to the MBH reconstruction, whether it got said in the IPCC report or not.

That this inconvenient fact has driven hundreds of blog posts, dozens of fevered accusations, a basket load of FOI requests, and stoked multiple fires of manufactured outrage is far more a testimony to personal obsession, rather than to its intrinsic importance. The science of paleo-reconstructions has moved well beyond this issue, as has the interest of the general public in such minutiae. We can however expect the usual suspects to continue banging this drum, long after everyone else has gone home.

Live-blogging the climate science hearings

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I will be live-blogging the House Energy and Commerce committee hearings on climate science with Eli Kintisch. The details are available here, and there should be a live feed from the committee website from 10am.

Eli and I did this last year for the last Democrat-run hearings, and it went quite well – a little like a play-by-play from Eli and some background analysis/cites from me. People can ask questions and comment in real time and depending on how busy it gets, they might get a response.

As usual, this hearing will likely be long on political grandstanding and short on informed discussion, but there might be some gems. Of the witnesses, John Christy and Roger Pielke Sr. are the main witnesses for the majority side, while Richard Somerville, Francis Zwiers and Chris Field are the Dem invitees. There is newcomer to the roster (at least to me), in Knute Nadelhoffer, who presumably will discuss climate change impacts on biological systems (but I don’t really know). There is one out-of-left-field witness, Donald Roberts, who is a serially wrong DDT advocate who is probably there in order to dismiss environmental regulation in general, following the well-worn strategy described in Oreskes and Conway’s “Merchants of Doubt” (Chapter 7 on the revisionist attacks on Rachel Carson) (NB. DDT-related arguments are off topic for this blog, but for background of the specifics of the DDT ‘meme’ see this summary, and interested commenters are encouraged to go to Deltoid).

Anyway, for those who are aficionados of science as contact sport (TM, Steve Schneider), it might be fun.

Update: This was also live-blogged at ClimateCentral and twittered by UCS.