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The nation’s freaky February warmth was assisted by climate change

March 8, 2017 at 3:03 p.m. EST
Temperatures compared to normal during February. (NOAA)

For the Lower 48 states it was a freaky February. The month’s average temperature of 41.5 degrees, some 7.3 degrees above normal, was more typical of March when the average temperature is 41.2 degrees.

The National Oceanic and Atmospheric Administration announced Wednesday that it was the second warmest February in 123 years of record-keeping, trailing only February 1954 by just 0.2 degrees. East of the Rocky Mountains, it was the warmest February ever recorded.

Human-induced climate warming likely played a helping hand in the high temperatures. Climate Central, a nonprofit science communication organization, produced an analysis finding that climate change made the month’s extreme warmth three times as likely, compared with 120 years ago.

“Temperatures like those seen across the Lower 48 this past February are becoming more and more common as cold winter months are getting rarer,” said Geert Jan van Oldenborgh, lead author of the analysis and researcher at the Netherlands Meteorological Institute (KNMI), in a news release. “The observations show a clear trend and climate models confirm it is caused by greenhouse gases.”

One of the month’s leading indicators of warmth was the lopsided number of record warm temperatures compared with record cold. NOAA said 11,743 daily record highs were set while it logged only 418 record lows — a ratio of 28 to 1. In 1,151 cases, the daily record highs were the warmest ever observed during February.

The following cities and many others registered their all-time highest February temperatures: Boston; Buffalo; Albany, N.Y.; Scranton, Pa.; Binghamton, N.Y.; Allentown, Pa.; Dayton, Ohio; Cincinnati; Columbus, Ohio; Milwaukee, and Madison and Green Bay, Wis.

Scores of northeastern U.S. cities just had their warmest February ever recorded

Sixteen states had their warmest February on record, concentrated in the South, Midwest, Mid-Atlantic and Northeast. Within these areas, it was the warmest February for Atlanta, Cleveland, Washington, Baltimore, Philadelphia and New York, to name just a few.

R.I.P. winter, we hardly knew ye

The abnormally warm temperatures accelerated the onset of spring. The season arrived three to four weeks early in the South and Mid-Atlantic, according to the U.S.A. National Phenology network, which tracks spring’s timing based on the emergence of green leaves and flowers.

With greenhouse gases continuing to accumulate in the atmosphere, warm Februarys and earlier starts to spring are likely to become even more common.”[T]he frequency of winter months like February 2017 should be expected to increase over the coming decades,” Climate Central’s analysis concluded.