Year 2012 Top Ten Warmest

The World Meteorological Organization’s Statement on the Status of the Global Climate says that 2012 joined the ten previous years as one of the warmest — at ninth place — on record despite the cooling influence of a La Niña episode early in the year.

The 2012 global land and ocean surface temperature during January–December 2012 is estimated to be 0.45°C (±0.11°C) above the 1961–1990 average of 14.0°C. This is the ninth warmest year since records began in 1850 and the 27th consecutive year that the global land and ocean temperatures were above the 1961–1990 average, according to the Statement.

“Although the rate of warming varies from year to year due to natural variability caused by the El Niño cycle, volcanic eruptions and other phenomena, the sustained warming of the lower atmosphere is a worrisome sign,” said WMO Secretary-General Michel Jarraud. “The continued upward trend in atmospheric concentrations of greenhouse gases and the consequent increased radiative forcing of the Earth’s atmosphere confirm that the warming will continue,” he said.

“The record loss of Arctic sea ice in August-September — 18% less than the previous record low of 2007 of 4.17 million km2 — was also a disturbing sign of climate change,” said Mr Jarraud. “The year 2012 saw many other extremes as well, such as droughts and tropical cyclones. Natural climate variability has always resulted in such extremes, but the physical characteristics of extreme weather and climate events are being increasingly shaped by climate change,” he said.

“For example, because global sea levels are now about 20 cm higher than they were in 1880, storms such as Hurricane Sandy are bringing more coastal flooding than they would have otherwise,” said Mr Jarraud.

WMO’s annual statements gather the key climate events of each year. The series stands today as an internationally rec­ognized authoritative source of information about temperatures, precipitation, extreme events, tropical cyclones, and sea ice extent.

During 2012, above-average temperatures were observed across most of the globe’s land surface areas, most notably North America, southern Europe, western Russia, parts of northern Africa and southern South America. Nonetheless, cooler-than-average conditions were observed across Alaska, parts of northern and eastern Australia, and central Asia

Precipitation across the globe varied significantly during 2012; however, some features were prominent, such as the drier-than-average conditions across much of the central United States, northern Mexico, northeastern Brazil, central Russia, and south-central Australia. Wetter-than-average conditions were present across northern Europe, western Africa, north-central Argentina, western Alaska, and most of northern China.

Hurricane Sandy killed close to 100 people and caused major destruction in the Caribbean before developing further strength and causing tens of billions of US dollars in damage and around 130 deaths in the eastern United States of America. Typhoon Bopha, the deadliest tropical cyclone of the year, hit the Philippines – twice – in December. During the year, the United States and south-eastern Europe experienced extreme drought conditions, while West Africa was severely hit by extreme flooding. The populations of Europe, northern Africa and Asia were acutely affected by extreme cold and snow conditions. Severe flooding occurred in Pakistan or a third consecutive year.

Climate change is aggravating naturally occurring climate variability and has become a source of uncertainty for climate-sensitive economic sectors like agriculture and energy.

“It is vital that we continue to invest in the observations and research that will improve our knowledge about climate variability and climate change,” said Mr Jarraud.

“We need to understand how much of the extra heat captured by greenhouse gases is being stored in the oceans and the consequences this brings in terms of ocean acidification. We need to know more about the temporary cooling effects of pollution and other aerosols emitted into the atmosphere. We also need a better understanding of the changing behaviour of extreme weather and climate events as a consequence of global warming, as well as the need to assist countries in the most affected areas to better manage climate-related risks with improved early warning and climate watch systems,” said Mr Jarraud.

The Global Framework for Climate Services (GFCS), adopted by the Extraordinary World Meteorological Congress in 2012, now provides the necessary global platform to inform decision-making for climate adaptation through enhanced climate information.

WMO is the United Nations' authoritative voice on weather, climate and water