2015 As The Warmest Year

Odds Increasing That 2015 Will Be Warmest Year

  The year’s potentially chart-topping heat has been driven in part by an El Niño that could rival the strongest on record, but it is also something that is more likely to happen now thanks to the steady accumulation of heat in the atmosphere trapped by greenhouse gases.

  The August temperature numbers also come in at a time when Arctic sea ice extent is heading toward its annual summer minimum, likely to happen this week. Scientists who monitor the sea ice expect this year’s minimum will rank as the fourth lowest in records extending back to the late 1970s.

  The monthly global temperature records kept by NASA show this August was the second hottest on record going back to 1880, only a hair behind August 2014. The summer as a whole was also the warmest. El Niño ramped up throughout  the season, with the World Meteorological Organization and the U.S. National Oceanic and Atmospheric Administration (NOAA) both declaring it a strong event within the last couple of weeks.

  Heat has helped to drive California’s deep drought. It was a factor in the state recording its lowest mountain snowpack in not only 120 years of measurements, but in at least 500 years, according to a new study that looked at historical tree ring records.The heat has also intensified the dry conditions that have led to devastating wildfires, such as the Valley Fire that exploded in size over the weekend and has led to at least one death and destroyed hundreds of homes. There is hope that El Niño will bring California more rains that could begin to quench the parched state.

 

Carbon dioxide levels have risen from a preindustrial level of about 280 parts per million to nearly 400 ppm today; CO2 concentrations this year stayed above the 400 ppm mark for six months, an increase over last year’s three months that shows the steady uptick.

This well-established global warming trend effectively loads the dice toward heat records as time goes on. Thirteen of the 15 warmest years have occurred since 2000, a circumstance that would only have 1-in-27 million odds of occurring without warming, according to a Climate Central analysis.

Original Article: http://www.wunderground.com/news/2015-likely-warmest-year-on-record