Notions that global warming has somehow paused in recent years are groundless, according to the United Nations’ World Meteorological Organization, whose annual report on global climate finds that 13 of the 14 warmest years in world history have occurred since the year 2000.
The report, issued Monday, also finds that each of the last three decades has been warmer than the one just preceding.
On its own, 2013 was the sixth warmest year on record worldwide, according to the WMO. Although a few regions of the globe were cooler than normal — including the central United States — Australia had its hottest year ever, Argentina its second-hottest, and New Zealand its third.
In a statement accompanying the report, the WMO’s secretary general said “there is no standstill in global warming,” as climate-science skeptics have been asserting.
“The warming of our oceans has accelerated, and at lower depths,” Michel Jarraud continued. “More than 90 percent of the excess energy trapped by greenhouse gases is stored in the oceans.
“Levels of these greenhouse gases are at record levels, meaning that our atmosphere and oceans will continue to warm for centuries to come. The laws of physics are non-negotiable.”
Heat waves and typhoons
The French meteorologist, who has headed the WMO since 2004, acknowledged that “naturally occurring phenomena such as volcanic eruptions or El Niño and La Niña events have always contributed to frame our climate, influenced temperatures or caused disasters like droughts and floods.
“But 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.”
Other extreme events listed in the report:
- Severe drought in Angola, Botswana and Namibia, in southern China, and in northeastern Brazil, where conditions were at their worst and a half century.
- Severe flooding following unusually heavy rains in the Sudan, Somalia, northeastern China, the Eastern Russian Federation, and along the India-Nepal border.
- Unprecedented snowfalls in Israel, Jordan and Syria.
- The widest U.S. tornado ever observed in El Reno, Okla.
- And, of course, greenhouse-gas concentrations reached record highs worldwide.
Closeup on North America
The report includes a section of regional highlights from the 2013 weather year; including these for North America:
Temperatures across most of North America were above average during 2013, but were more moderate overall than in 2012. Winter was warmer than average in Canada and the United States, although spring in the contiguous United States was the coolest since 1996. Temperatures in the United States rebounded during the summer, and the warmth continued into September.
Summer in Alaska was the second hottest on record, and October-December was the sixth warmest such period on record for the state. Mexico experienced a record warm July and August and a warm autumn.
In Canada, 2013 was the thirteenth driest year on record. Nevertheless, torrential downpours overwhelmed Calgary and vast areas of southern Alberta in June, forcing 100,000 people to evacuate their homes and causing close to US$ 6 billion in damage. The contiguous United States was wetter than average for the year, with some geographical variations. Two states, Michigan and North Dakota, experienced record wet conditions. Alaska observed its third wettest year on record and the wettest in the past 50 years.
A major drought that encompassed large parts of the central United States in 2012 and early 2013 improved across much of the country. By the end of 2013, about 31 per cent of the country was experiencing drought, down from about 61 per cent at the beginning of the year. California had its driest year since records began in 1895; San Francisco received only 16 per cent of its average annual rainfall since local records began in 1947. Very hot conditions, combined with strong winds and drought, contributed to the worst wildfire in Colorado history.
The contiguous United States was hit by several late-season winter storms. In April, Bismarck, N.D., received 44 cm of snow, setting a new calendar-day record. Duluth, Minn., and Rapid City, S.D., each had their snowiest month on record, with 129 cm and 109 cm, respectively. El Reno, Okla., was struck by a particularly powerful tornado: at 4 3 km, it was the widest tornado ever observed in the United States.
Rankings differ, but only slightly
Interesting coverage of the report included a piece in the Christian Science Monitor, pointing out that while the WMO counts 2013 as the sixth warmest year on record (in a tie with 2007), the year was ranged seventh warmest by scientists at the National Aeronautics and Space Administration (NASA) and fourth by scientists at the National Oceanic and Atmospheric Administration (NOAH).
The difference in rankings can be mindboggling, but apparently, the differences in temperature recordings is tiny, say experts.
“The difference between the joint fourth place and the joint seventh place is within 0.02 C of a degree,” Gavin Schmidt, deputy director of NASA’s Goddard Institute for Space Studies told CBCnews in January. He also added that NASA and NOAA process their data differently.
“Different data and averaging methods lead to slightly different global temperature estimates that can lead to small switches in the ranking of years,” Harvard University climate expert Peter Huybers told the Monitor.
But “the key point here is that, no matter how you slice it, 2013 was among the top 10 warmest years, as have been most recent years,” Michael Mann, a climatologist at Penn State University, told Climate Central.
And in an interview with Voice of America, Jarraud observed that “since 2001, the first year of this Century, the coldest year that we have observed since 2001 is actually warmer than any year before 1998.”
Jarraud also told VOA that “there is a strong possibility of an El Nino developing near the end of this year. El Nino is a complex interaction between the atmosphere and the ocean.
“If El Nino is confirmed, Jarraud says the world can expect a warmer year.”