Humans Implicated in String of Record-Warmth Years

Human activities are the cause of this century’s record warm years, according to a study in the journal Scientific Reports.

“We find that individual record years and the observed runs of record-setting temperatures were extremely unlikely to have occurred in the absence of human-caused climate change,” the authors say. “These same record temperatures were, by contrast, quite likely to have occurred in the presence of anthropogenic climate forcing.”

The study, written before the release of 2015 temperature data, put the odds between 1 in 770 and 1 in 10,000 that 13 of the 15 warmest years spanning from 2000 to 2014 happened without human influence (subscription). With the inclusion of 2015 temperature data, the group’s computer simulations widened those odds to between 1 in 1,250 and 1 in 13,000, lead author Michael Mann, a professor of meteorology at Pennsylvania State University, told Reuters.

“Climate change is real, human-caused and no longer subtle—we’re seeing it play out before our eyes,” Mann said.

Mann and his co-authors ran statistical analyses of real-world measurements and comprehensive computer simulations of the climate system to distinguish human-caused climate change from natural climate variability, such as that triggered by volcanic eruptions and shifts in the sun’s output.

“2015 is again the warmest year on record, and this can hardly be by chance,” Stefan Rahmstorf, a co-author from the Potsdam Institute of Climate Impact in Germany, said. “Natural climate variations just can’t explain the observed recent global heat records, but man-made global warming can.”

Study: Low Electricity Costs and Low Emissions Not Mutually Exclusive

A new study by National Oceanic and Atmospheric Administration (NOAA) and University of Colorado Boulder researchers in the journal Nature Climate Change finds that the United States could reduce carbon dioxide emissions from electricity generation (using future anticipated costs for wind and solar) by —> Read More