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Major NOAA report: Climate change intensified 2012 record heat in U.S.

2012 U.S. temperatures – difference from average (NOAA.)

Manmade climate change played a substantial role in the exceptional warmth in the eastern U.S. during the spring of 2012, a major NOAA-led report concludes. Not only that, it greatly increased the odds of the punishing heat that baked the north central and northeast U.S. during the summer that followed.

“Approximately 35 percent of the extreme warmth experienced in the eastern U.S. between March and May 2012 can be attributed to human-induced climate change,” NOAA says about the results of one of the report’s 18 studies.

Drawing from another study, NOAA adds: “High temperatures, such as those experienced in the [north central and northeast] U.S. in [summer] 2012 are now likely to occur four times as frequently due to human-induced climate change.”

In 2012, Washington, D.C. had its warmest spring on record and third hottest summer (including 8 100+ degree days, and a record-tying 28 95+ degree days).

The NOAA report adds weight to a large body of scientific studies that show manmade climate change is very likely affecting the intensity of warm weather now and will in the future.

Adding to this, news of record-breaking warmth around the globe is a seeming constant. Although the summer heat in the U.S. in 2013 was rather ordinary and fell well short of matching 2012’s record-setting level, exceptional warmth/heat occurred in many other places, from the South Pole to Shanghai to Siberia.

Just today, Australia’s Bureau of Meteorology announced that the southern hemisphere continent had just completed its warmest 12-month period on record.

Although links between human-induced climate change and some extreme weather phenomena are minimal (tornadoes) to equivocal (hurricanes), the evidence that warm weather extremes are increasing is difficult to dismiss, in my view.

Post script: the full NOAA report is well-worth a read. It analyzes 12 instances of extreme weather and climate events around the globe in 2012 and finds about half of them were impacted by human-caused climate change.