27 July 2015, Yale Climate Connections, From Warming Estimates to Measurements. Scientists measure the heat trapped by atmospheric carbon dioxide for the first time. Feldman: “People have long talked about CO2 being a greenhouse gas, but the actual greenhouse effect, that’s the actual warming of the atmosphere caused by CO2, has not been measured in the field.” That’s Daniel Feldman of the Lawrence Berkeley National Laboratory. He says no one had actually measured the link between increased carbon dioxide in the atmosphere and rising temperatures, because it requires a lot of very high quality measurements over a long period of time. By looking at weather data collected over eleven years in Oklahoma and Alaska, Feldman was able to pinpoint the exact amount of infrared radiation, or heat, being trapped by increasing amounts of atmospheric carbon dioxide, instead of being released into space. Using very precise instruments, he determined how much of the warming came from CO2 instead of other sources. It’s significant because Feldman was able to measure the exact relationship between increased carbon dioxide in the atmosphere and additional energy, or heat, at the earth’s surface. His results are very consistent with the estimates of climate change computer models, and the measurements will help scientists develop even more accurate predictions of future global warming. Read More here
27 July 2015, The Guardian, The Daily Mail and Telegraph get it wrong on Arctic sea ice, again: Coverage of a recent paper on Arctic sea ice and climate change suggests conservative media can’t seem to grasp the concept of long-term trends. Cherry-picking is one of the five telltale techniques of climate change denial. By focusing on short-term blips in noisy data, those who want to maintain the status quo can distract from the long-term threats posed by climate change. Climate contrarians most frequently deploy this strategy using global temperature and Arctic sea ice data. A recent study in Nature Geoscience concluded that, not surprisingly, there is a strong relationship between the summer temperatures in the Arctic (specifically the number of “melting degree days”), and the amount of sea ice that melts in a given year. 2013 happened to be a relatively cool year in the Arctic – the coolest since 2004. As a result, there was relatively little ice melt in 2013. The annual minimum Arctic sea ice extent and volume were their largest since at least 2009, or perhaps as far back as 2005, according to the data used in this new study. The following figure from the paper is as clear as ice – while there was a short-term increase from 2012 to 2013, the Arctic has lost more than half its sea ice over the past three decades. Read More here