In an editorial this weekend in the Wall Street Journal, columnist Holman Jenkins scoffed at the reporting of the NOAA statement that 2012 was the hottest year ever in the instrumental record in these United States.
When the National Oceanic and Atmospheric Administration says 2012 was the hottest year on record in the "contiguous United States," trust the media to transcribe the statement accurately. A disaster for public understanding begins only when the media stop transcribing and start using their own brains.
Said the New York Times climate blog, in an assertion that was echoed throughout the media: "The temperature differences between years are usually measured in fractions of a degree, but 2012 blew away the previous record, set in 1998, by a full degree Fahrenheit."
Really? If that were true, then hair-on-fire news should have been the fact that 2012 was 2.13 degrees hotter than 2011. That's a far more dramatic change, and in a single year.
Nor was it mentioned that 2008, in the contiguous U.S., was two degrees cooler than 2006. Or that 2000, 2002, 2003, 2004, 2008, 2009, 2010 and 2011 were all cooler than 1998 by a larger margin than 2012 was hotter than 1998.
Are you getting the picture? None of this was mentioned because it makes a mockery of using trends in the Lower 48 as a proxy for global warming, the misguided intent that permeated media coverage of the NOAA revelation.
The contiguous United States isn't the globe. It isn't even the United States, omitting Alaska and Hawaii. The Lower 48 represent just 1.58% of the total surface area of the Earth. The law of large numbers is at work here: The smaller the sample, the more volatile its patterns compared to a larger sample. And the fact remains, in all the authoritative studies, the warmest year on record globally is still 1998 and no trend has been apparent globally since then.
In response to this, and to another misleading editorial in the paper, Jeffrey Sachs, director of the Earth Institute at Columbia University, calls on the WSJ to get a fact-checker for its editorialists.
Actually, our leading climatologist, James Hansen, today did fact check the claim that "global warming has stopped," with the respect for facts of a true scientist. Please note that he seconds Jenkins' remarks re: the temperature record in the last ten years:
Global Warming Standstill. The 5-year running mean of global temperature has been flat for the past decade. It should be noted that the "standstill" temperature is at a much higher level than existed at any year in the prior decade except for the single year 1998, which had the strongest El Nino of the century. However, the standstill has led to a widespread assertion that "global warming has stopped". Examination of this matter requires consideration of the principal climate forcing mechanisms that can drive climate change and the effects of stochastic (unforced) climate variability.
The climate forcing most often cited as a likely natural cause of global temperature change is solar variability. The sun's irradiance began to be measured precisely from satellites in the late 1970s, thus quantifying well the variation of solar energy reaching Earth (Fig. 4). The irradiance change associated with the 10-13 year sunspot cycle is about 0.1%. Given the ~240 W/m2 of solar energy absorbed by Earth, this solar cycle variation is about 1/4 W/m2 averaged over the planet. Although it is too early to know whether the maximum of the present solar cycle has been reached, the recent prolonged solar minimum assures that there is a recent downward trend in decadal solar irradiance, which may be a decrease of the order of 0.1 W/m2. Although several hypotheses have been made for how the solar irradiance variations could be magnified by indirect effects, no convincing confirmation of indirect forcings has been found except for a very small amplifying effect via changes of stratospheric ozone.
A slower growth rate of the net climate forcing may have contributed to the standstill of global temperature in the past decade, but it cannot explain the standstill, because it is known that the planet has been out of energy balance, more energy coming in from the sun than energy being radiated to space.10 The planetary energy imbalance is due largely to the increase of climate forcings in prior decades and the great thermal inertia of the ocean. The more important factor in the standstill is probably unforced dynamical variability, essentially climatic "noise"…
Indeed, the current stand-still of the 5-year running mean global temperature may be largely a consequence of the fact that the first half of the past 10 years had predominately El Nino conditions, while the second half had predominately La Nina conditions (Nino index in Fig. 1). Comparing the global temperature at the time of the most recent three La Ninas (1999-2000, 2008, and 2011-2012), it is apparent that global temperature has continued to rise between recent years of comparable tropical temperature, indeed, at a rate of warming similar to that of the previous three decades. We conclude that background global warming is continuing, consistent with the known planetary energy imbalance, even though it is likely that the slowdown in climate forcing growth rate contributed to the recent apparent standstill in global temperature.
Hansen posts a graph that shows the baseline shift in temperature anomalies in the U.S.:
The New Climate Dice. The high current global temperature is sufficient to have a noticeable effect on the frequency of occurrence of extreme warm anomalies. The left-most "bell curve" in Fig. 3 is the frequency distribution of summer-average temperature anomalies during the base period 1951-1980, in units of the local standard deviation1 of seasonal-average temperature.
The observational data show that the frequency of unusually warm anomalies has been increasing decade by decade over the past three decades. Perhaps the most important change is the emergence of extremely hot outliers, defined as anomalies exceeding 3 standard deviations. Such extreme summer heat anomalies occurred in 2010 over a large region in Eastern Europe including Moscow, in 2011 in Oklahoma, Texas and Northern Mexico, and in 2012 in the United States in part of the central Rockies and Great Plains.
The location of these extreme anomalies is dependent upon variable meteorological patterns, but the decade-by-decade movement of the bell curve to the right, and the emergence of an increased number of extreme warm anomalies, is an expression of increasing global warming. Some seasons continue to be unusually cool even by the standard of average 1951-1980 climate, but the "climate dice" are now sufficiently loaded that an observant person should notice that unusually warm seasons are occurring much more frequently than they did a few decades earlier.
I can't help but contrast the focus on fact from Hansen vs. the wild charges of Holman, who drags tax reform, the media, politicians, and other irrelevancies into his attempt to discredit the facts of global warming.