Over the past few weeks, there has been much discussion of global surface temperatures, as 2016 broke the previous 2015 record in all surface temperature series. Here I will place 2016 in context, highlighting the role of rapid Arctic warming in recent surface temperature evolution as seen in a comparison of four operational data sets. The 2016 increase over 2015 was much larger in the analyses that account for missing areas, especially the Arctic, providing additional impetus to address coverage bias among research groups that still have not done so. I’ll also take a quick look at the growing effect of residual biases from ship-buoy measurement adjustments in sea surface temperature (SST) analyses in recent years, which has led to some additional divergence between the two major operational SST series underlying these four global series.
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There has been a big change at WIREs Computation Stats.
In a stunning (but welcome) development, James Gentle of GMU and Karen Kafadar of IndianaUniversity have been named editors-in-chief, joining remaining original editor David Scott.
I last discussed WIREs Comp Stat back in July, when Edward Wegman and Yasmin Said were quietly dropped as editors. I outlined the problems that apparently led to their summary dismissal.
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Yes, the Deep Climate blog is finally returning after a hiatus of several months. Over the next few months, look for at least two or three posts per month, as I gradually return to former activity levels. Thanks to everyone for their patience.
Here are some topics that could be discussed on this open thread.
1) Margaret Munro of Post Media has reported on the latest initiative to fight muzzling of Canadian scientists by the Harper government.
Federal Information Commissioner Suzanne Legault is being asked to formally investigate the way the Harper government has been “muzzling” and restricting access to federal scientists.
The request, accompanied with a report [7Mb PDF] on the government’s “systematic efforts” to obstruct access to researchers, was made jointly on Wednesday by the Environmental Law Centre at the University of Victoria and Democracy Watch, a national non-profit group.
2) The IEA Energy Technology Perspectives 2012 report has just been issued, together with a detailed online presentation. In my opinion, this is “must read” for anyone interested in climate policy, and realistic pathways to avoiding the worst effects of climate change. There is, of course, still a yawning gap between current government policies and policies required to limit global warming to about 2 deg C above pre-industrial levels.
3) Russell Seitz has started a very entertaining blog entitled VVattsUpWithThat (yes, that’s a double V!). A recent post discusses the conviction of Heartland Institute science director Jay Lehr for defrauding the EPA in the early 1980s.
The eleventh domino has fallen.
The extraordinary 2012 Arctic sea ice melt has resulted in a September average sea ice extent of 3.61 million sq km, according to the latest monthly data from the National Snow and Ice Data Center (NSIDC), smashing the previous record of 4.30 million sq km set in 2007.
Today, I’ll quickly review the last month’s progression. I’ll then examine the plausible future course of the Arctic sea ice “death spiral” that is likely to see the Arctic virtually free of sea ice by the 2030s if not sooner, culminating with a new graphic representation of the Arctic sea ice death spiral.
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A recent Canadian radio appearance by Berkeley Earth founder Richard Muller has shed additional light on the role of Charles Koch, a major funder of the Berkeley Earth effort (and arguably the top funder of climate contrarians over the last several years). In the interview on CBC’s Sunday Edition, Muller mounted his most spirited and detailed defence of Koch yet, describing the oil billionaire as “very thoughtful” and “properly skeptical” of climate science. And the Berkeley Earth website goes even further, linking to an official Koch statement that makes the preposterous claim that the Charles Koch Foundation supports “sound, nonpartisan, scientific research”. That rings especially hollow this election season, given the current massive pro-Republican and anti-regulation push by fossil fuel interests, led as usual by Koch Industries. Continue reading →
Climate change got its first mention of the U.S. political season with Mitt Romney’s “heal the planet” crack, and Obama’s memorable retort:
And yes, my plan will continue to reduce the carbon pollution that is heating our planet – because climate change is not a hoax. More droughts and floods and wildfires are not a joke. They’re a threat to our children’s future. And in this election, you can do something about it.
For a Canadian perspective that somehow managed to miss the point of Romney’s ill-advised, small-minded joke, check out Andrew Coyne in the National Post.
Meanwhile, Canadian environment minister Peter Kent announced regulations for coal-fired electricty that are weaker than the original proposal of a year ago, while the government met renewed accusations of creative carbon accounting.
Interest in 2012’s record Arctic sea ice melt has reached the mainstream press both here in Canada (CBC, PostMedia) and abroad (New York Times, Associated Press and the Guardian), now that the Colorado-based National Snow and Ice Data Center (NSIDC) has declared a record low in Arctic sea ice extent.
In my previous discussion of the extraordinary 2012 melt, I noted the eclipse of the old daily record on August 24, three weeks ahead of the 2007 pace. But I also gave a series of short-term projections for the September extent average, which is the metric typically used to track the decline in Arctic sea ice. The 2012 September projection now stands at 3.56 million sq km, slightly down from my previous projection of 3.67 million sq km. That’s more than 700,000 sq km less than the previous 2007 record of 4.30 million sq km.
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[UPDATE Aug 24-28: The previous record low for daily Arctic sea ice extent was 4.16 million sq km, set on September 14, 2007. The new record was first set on August 24, 2012 and now stands at 3.85 million sq km. Sea ice extent was reduced by more than 430,000 sq km in five days (Aug 23-27), the most rapid late August loss on record. Click on thumbnail at right for latest Arctic sea ice extent as of today (based on latest NSIDC daily data).
- Aug 22: 4.29 million sq km
- Aug 23: 4.19 million sq km
- Aug 24: 4.09 million sq km ***
- Aug 25: 3.97 million sq km
- Aug 26: 3.94 million sq km
- Aug 27: 3.85 million sq km
*** New record low for daily Arctic sea ice extent set on Aug 24.]
This year’s arctic ice melt season is generating extraordinary interest. 2012’s apparent descent toward a new record low in extent and area is dramatic enough, but it also comes as new analysis shows that summer sea ice loss is 50% more than previously thought in terms of volume, according to preliminary satellite data from CyroSat 2. Virtually ice-free summers in the arctic sea could well arrive by 2030, with troubling implications for accelerated albedo feedback and possibly disruptive changes in the jet stream.
A new record low, eclipsing 2007, does seem increasingly inevitable with each passing week. National Snow and Ice data Center data showed Arctic sea ice extent at 4.29 million square km yesterday, just under 2007’s September average, and a level only reached on September 7 back then. To be sure, 2012 is starting to bottom out, but most years have seen a similar pattern around now.
Here’s a snapshot of the 2012 melt season (with the small crosses denoting recent daily values), compared to the previous five years.
Just how low could 2012 go?
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[UPDATE 08/17: In comments, Berkeley Earth team member Zeke Hausfather reveals that most of the discrepancy between the Berkeley Earth 2011 and 2012 results is due to a previously unreported error in latitudinal weighting in the earlier version.
UPDATE 08/20: The 2012 GHCN-only series has been uploaded by Zeke Hausfather. Also, I have added clarifications concerning absolute temperature uncertainty and data availability. The summary has been updated accordingly.]
The recent Berkeley Earth land-surface average temperature series is based on a greatly expanded database of station temperature data, along with a completely automated statistical averaging process. In contrast, established average temperature series from NOAA, NASA and HadCrut are based primarily on the smaller Global Historical Climate Network (GHCN) database, and use empirically derived homogenization methods to remove known biases, albeit supplemented by pure statistical methods.
Here, the post-1950 Berkeley Earth “complete” land series is compared to the preliminary Berkeley series released in 2011, as well as to GHCN-only simulated series, based on overall attributes of those unreleased series provided in the Berkeley Earth companion “methods” paper. The 2011 and 2012 “full” (ALL) series Berkeley versions both fall squarely in the range of the latest comparable series from the three other groups post-1950. However, the two Berkeley ALL series diverge over the 1980-2010 period, and lie completely outside each others’ 95% confidence intervals in the 2000s, when baselined to 1950-1979. This turns out to be due to a significant error in latitudinal weighting in the 2011 ALL series; the error was not publicly disclosed at the time of correction. The GHCN 2012 series falls halfway between the 2012 ALL and 2011 ALL series in the 2000s; 2012 GHCN and 2012 ALL each appear to diverge outside the other’s confidence interval in the 2000s. As well, there is an increasing widening between the 2012 GHCN and ALL series the further one goes back before the 1950-1979 baseline period, with the ALL series about 0.3 C cooler in the early 1800s.
Other issues requiring further analysis are also identified, particularly a reported reversal in the long-term trend of narrowing diurnal temperature range starting in 1987, which contradicts previous GHCN-based analyses.Taken together, these issues cast doubt on the robustness of the present Berkeley Earth analysis, and point up the need for more open data access and improved diagnostics in order to further assess the reliability of the Berkeley Earth approach to surface temperature analysis.
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This month we kick things off with the renewed attacks on Tides Canada by oilsands booster (and Canadian Conservative government surrogate) Ethical Oil [h/t Holly Stick].
Meanwhile, Canadian environment minister Peter Kent is touting an improved outlook for meeting Canada’s 2020 goal for GHG reduction, even though any progress is more due to luck, accounting changes and strong action by some provincial governments, rather than any concrete action by the federal government. Not to mention that current projections for 2020 still leave Canada only 3% under 2005 levels, 19% above the promised target. I’m working on a couple of related posts, but they may take a little time yet.
The latest release from the Berkeley Earth team has unleashed a major kerfuffle in the blogosphere, out of all proportion with its scientific import. (By the way, I have a post on Berkeley Earth coming very soon, looking at some curiosities in the various Berkeley results).
Getting back to the science, arctic sea ice continues to melt at an extraordinary pace, and may well set a new record low this September.