Global warming deniers got their shorts in a bunch after 2014 was declared the hottest year since 1880 by NASA and NOAA, followed by the World Meteorological Association and the Japan Meteorological Organization. Only the Hadley Center in Britain declined to join the other four. Hadley’s reservation was due to the small certainty of the findings: Chris Mooney wrote that Hadley that “the uncertainty ranges mean it’s not possible to definitively say which of several recent years was the warmest.” On the other hand, the four consensus makers saw their numbers as the most justified.
Climate deniers reacted to “warmest year” claims with outrage. For example, James Delingpole titled his piece “Global Warming: So Dishonest it Makes Enron Look Like a Paragon of Integrity.” The New American titled its article “Global Conning: Temperature Data Cooked in “Biggest Science Scandal Ever” And Christopher Booker, echoing the New American, headlined his article in The Telegraph (England) with “The fiddling with temperature data is the biggest science scandal ever.”
One of the issues that deniers focused on was the adjustments of temperatures records to make temperatures appear to increase. But, it wasn’t a scandal. In fact, scientists make adjustments to data captured in the “wild” all the time. An excellent article by Scicheck the Wire explains why such data are routinely adjusted. The author quotes a NOAA comment on just this issue:
Q: What are some of the temperature discrepancies you found in the climate record and how have you compensated for them?
Over time, the thousands of weather stations around the world have undergone changes that often result in sudden or unrealistic discrepancies in observed temperatures requiring a correction. For the U.S.-based stations, we have access to detailed station history that helps us identify and correct discrepancies. Some of these differences have simple corrections.
SciCheck elaborated on a number of reasons for these differences, e.g., “even just the addition or subtraction of nearby buildings.” In fact, as the chart below show, upward and downward corrections are about equal http://www.factcheck.org/2015/02/nothing-false-about-temperature-data/.
The twentieth-twenty-first century record so far shows us something alarming: While it is possible to quibble about which year in the immediate past is the warmest, the trend should be pretty clear to anyone with an open mind, as the chart below shows.
The fact is that whether one year of another is “the warmest,” we are already a long way toward the 2 degrees Celsius mark