UN report: 2013's extreme weather is consistent with climate change

The World Meteorological Organization (WMO) released their annual State of the Climate report this past Sunday, to coincide with the World Meteorological Day. The report confirms that recent extreme weather events, such as droughts, floods, heat waves and tropical cyclones around the world, are linked to human-caused climate change.

"There is no standstill in global warming," said WMO Secretary-General, Mr. Michel Jarraud in a statement. "Many of the extreme events of 2013 were consistent with what we would expect as a result of human-induced climate change. We saw heavier precipitation, more intense heat, and more damage from storm surges and coastal flooding as a result of sea level rise - as Typhoon Haiyan so tragically demonstrated in the Philippines."

The WMO report shows that 2001-2010 was the warmest decade on record, and that the last three decades had been warmer than the previous one. In 2013, Australia had its hottest year on record while Argentina had its second hottest. 2013 tied with 2007 as the sixth-warmest on record. The continuing long-term trend of warming and these heat records could not have been possible without "human-induced influence on climate", i.e. global warming, the report concludes:

"Comparing climate model simulations with and without human factors shows that the record hot Australian summer of 2012/13 was about five times as likely as a result of human-induced influence on climate and that the record hot calendar year of 2013 would have been virtually impossible without human contributions of heat-trapping gases, illustrating that some extreme events are becoming much more likely due to climate change."

The report also shows that during 2013 greenhouse gas concentrations in the atmosphere reached record highs, global oceans reached new record high sea levels, and Antarctic sea ice extent reached a record daily minimum.

"2013 with its mixture of record warmth and extreme weather shows a now familiar mixture of natural variability and greenhouse gas induced climate change," said Prof Sir Brian Hoskins, director of the Grantham Institute for Climate Change at Imperial College London. "These annual statements document a striking long term trend, and one thing is clear: that our continuing greenhouse gas emissions are a crucial driving force in the changing climate."

Other key climate events of 2013, according to the WMO report:

• Typhoon Haiyan (Yolanda), one of the strongest storms to ever make landfall, devastated parts of the central Philippines.
  
• Surface air temperatures over land in the Southern Hemisphere were very warm, with widespread heat waves; Australia saw record warmth for the year, and Argentina its second warmest year and New Zealand its third warmest.
  
• Frigid polar air plummeted into parts of Europe and the southeast United States.
  
• Angola, Botswana and Namibia were gripped by severe drought.
  
• Heavy monsoon rains led to severe floods on the India-Nepal border.
  
• Heavy rains and floods impacted northeast China and the eastern Russian Federation.
  
• Heavy rains and floods affected Sudan and Somalia.
  
• Major drought affected southern China.
  
• Northeastern Brazil experienced its worst drought in the past 50 years.
  
• The widest tornado ever observed struck El Reno, Oklahoma in the United States.
  
• Extreme precipitation led to severe floods in Europe’s Alpine region and in Austria, Czech Republic, Germany, Poland, and Switzerland.
  
• Israel, Jordan, and Syria were struck by unprecedented snowfall.