David Appell has covered an interesting story with dueling scientists writing climate-related letters published in The Oregonian newspaper. It began with the newspaper publishing an opinion-editorial written by Gordon Fulks, who lives in Corbett, Oregon and has a background in physics. The editorial was full of conspiracy theories, inflammatory language, and several long-debunked climate myths. Among them was the myth that global warming stopped 15 years ago.
Oregon State climate scientist Andreas Schmittner responded with a letter to the editor, which focused primarily on debunking that particular myth.
"Fulks claims that global temperatures have not risen during the past 15 years. This is not true. Most heat trapped by carbon dioxide and other gases added to the atmosphere is absorbed by the oceans, as clearly seen in measurements available at the National Oceanic and Atmospheric Administration website ... Fulks flunks climate science. He cherry-picks information that supports his conclusion and ignores the rest. That's not science."
Schmittner is of course entirely correct on this issue, and it's critical to examine ocean heat content (OHC), because that's where over 90% of global warming goes. However, University of Rochester (New York) physics professor David Douglass decided to weigh in with his own letter to The Oregonian, supporting Fulks' climate misinformation with several factually incorrect statements of his own, including this one:
"My colleagues and I have actually analyzed and published papers using this [NOAA ocean heat content] data. We find no evidence of the earth warming."
This statement likely refers to Douglass & Knox (2012), which used NOAA OHC data from the upper 700 meter ocean layer to try and find evidence of "climate shifts". The paper argues that two of those "shifts" occurred in approximately 2002 and 2009, and that between those years, there was very little OHC increase (in the uppermost 700 meters of oceans). It is worth noting that 2002–2009 is of course only about half of the 15-year period during which Douglass claims OHC and global warming did not increase, so his claims in The Oregonian are indisputably factually wrong.
We at Skeptical Science are very familiar with the paper in question, because our paper Nuccitelli et al. (2012) was a comment on Douglass & Knox (2012). We pointed out that although the OHC increase in the upper 700 meters has slowed slightly in recent years, that is because more heat has been transferred to the 700–2000 meter ocean layer (Figures 1 and 2).
Figure 1: Land, atmosphere, and ice heating (red), 0-700 meter OHC increase (light blue), 700-2,000 meter OHC increase (dark blue). From Nuccitelli et al. (2012).
Figure 2: Comparison of Global Heat Content 0-700 meters layer vs. 0-2000 meters layer, from the National Oceanographic Data Center.
For those who would like to analyze the data for themselves, the NOAA OHC data are available here.
Given my familiarity with this research and data as the lead author of Nuccitelli et al. (2012), I sent my own letter to The Oregonian editor, and they were kind enough to publish it, though they edited it a bit first. Here is the unedited version:
On January 29th, a letter from professor David Douglass was published claiming that based on his analysis of data from the National Oceanic and Atmospheric Administration's National Oceanographic Data Center (NODC), there has been no global warming over the past 15 years. Last year, my colleagues and I published a correction to Professor Douglass' research, showing that there is no sign that global warming has even slowed in the NODC data.
In fact, heat is accumulating in the Earth's climate system due to the increased greenhouse effect at a faster rate today than it was 15 years ago, and the energy is equivalent to detonating four Hiroshima atomic bombs per second, every second over the past 15 years.
Oregon State's Professor Schmittner was entirely correct to note that global warming has continued at a very rapid rate over this timespan.
For more information, see http://www.sks.to/16years.
Dana Nuccitelli
Although there is no truth to the claim that global warming magically stopped 15 (or 16) years ago, the myth is remarkably pervasive. In fact, Douglass asserted that "Most climate scientists agree that that the earth has not warmed during the past 15 years", which of course is not even remotely true.
It is true that global surface temperatures have warmed at a relatively slow rate (though they have indeed most likely warmed) over the past ~15 years, due in part to a preponderance of El Niño events in the 1990s and a preponderance of La Niña events in the 2000s, due in part to increased heat accumulation in the deeper ocean layers, and due to several other contributing factors.
However, as Kevin C showed in his excellent video, the underlying human-caused global warming trend remains steady beneath the short-term noise, and as we showed in Nuccitelli et al. (2012), global heat accumulation has not slowed at all. In fact, heat has accumulated in the climate system at a faster rate over the last 15 years than it did in the previous 15 years.
Nevertheless, we expect to continue playing whack-a-mole with this zombie of a myth, which climate contrarians will simply not let die. However, the claim is nothing more than denial, pure and simple, based on cherrypicking and ignoring inconvenient data, as professor Schmittner correctly noted.
Posted by dana1981 on Monday, 4 February, 2013
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