Wondering if these recent cool summers mean something? Confused by the Freakonomics guys going all climate change-contrarian? Thinking that, perhaps, that you were too concerned about climate change 18 months ago?
If so, you may enjoy this sharp (and fairly short) piece from AP science writer Seth Borenstein (our emphasis):
Since 1998, temperatures have dipped, soared, fallen again and are now rising once more. Records kept by the British meteorological office and satellite data used by climate skeptics still show 1998 as the hottest year. However, data from the National Oceanic and Atmospheric Administration and NASA show 2005 has topped 1998. Published peer-reviewed scientific research generally cites temperatures measured by ground sensors, which are from NOAA, NASA and the British, more than the satellite data.
So Borenstein carried out a neat experiment: sending climate data to statisticians, without telling them what the data showed, and asked them to identify the trends:
The AP sent expert statisticians NOAA’s year-to-year ground temperature changes over 130 years and the 30 years of satellite-measured temperatures preferred by skeptics and gathered by scientists at the University of Alabama in Huntsville.
Statisticians who analyzed the data found a distinct decades-long upward trend in the numbers, but could not find a significant drop in the past 10 years in either data set. The ups and downs during the last decade repeat random variability in data as far back as 1880.
The sceptics get a say in the story, too. But their tendency to highlight a few years that deviate from the longer-term trend does not come across as very convincing.
