According to the World Meteorological Organization’s (WMO) Provisional Statement on the State of Global Climate in 2012, released at the Doha Climate Change Conference on 28 November 2012, the years 2001-2011 were among the warmest on record and the first ten months of 2012 yielded above-average temperatures globally. The Statement notes that January to October 2012 constituted the ninth warmest such span since records began in 1850, even despite a January-March cooling effect from La Niña. May-October 2012 was the fourth warmest such period on record. The Statement reports regional extreme variations in temperature, including: a warmer-than-average winter and summer in Canada and the contiguous US; cold winter in Europe and Asia; and notable warmth in southern Europe, northwestern Asia and parts of Africa and South America. Northern Hemisphere spring brought heat waves to much of the US and Europe. The report also cites global climate observations beyond high temperatures. Major wildfires and droughts affected much of the US and Spain, and droughts besieged other parts of Europe, Mexico, China, Kenya, and Brazil. Other regions experienced extreme precipitation and tropical cyclones. Arctic sea ice declined more rapidly in August 2012 than in any other August on record, according to the WMO statement. In September 2012, satellite observations revealed that arctic sea ice reached its lowest extent on record. The WMO statement suggests that the difference between the highest sea ice extent for 2012, in March, and lowest sea ice extent, in September, was the largest such difference in the 34-year record. Finally, greenhouse gases (GHGs) increased from 2010-2011 at a higher growth rate than at any time in the previous decade.