A panel of experts has ranked the top 10 global weather and climate events of 2010 as follows.
According to Christian Science Monitor, voters considered the scope and unusualness of the event, its immediate human and economic impact, and whether it is emblematic of climate trends or variability:
1. Russian-European-Asian heat waves
The heat waves of summer 2010 spawned drought, wildfires, and crop failures across western Russia, where over 15,000 people died. All-time high temperatures occurred in many cities and nations across the Northern Hemisphere. China faced locust swarms during July.
Temperatures hovered from four to eight degrees Celsius above average in Russia during June and July. On July 30th, Moscow recorded its highest temperature ever ? 39 degrees Celsius ? breaking the previous record of 37 degrees Celsius set just four days earlier. Prior to July 2010, the record hadn?t been broken for 90 years.
2. Warmest year on record (probably)
According to National Oceanic and Atmospheric Administration (NOAA), the globally averaged temperature for 2010 will finish among the two warmest, and likely the warmest, in the 130-year-climate record.
(The current record was set in 2005, and so far the two years are in a statistical tie, which may be resolved as data compilation continues.)
2001-2010 is the warmest 10-year period since the start of weather records in 1850, the UN weather agency said Dec 2.
3. Flooding in Pakistan
Monsoon rains fall in Pakistan every summer, but the rains in June and July 2010 were unusually heavy, bringing over a foot of rain.
By Aug 1, whole villages had washed away, over 1,600 people had died, six million had lost their homes, and about 20 million people were affected. The flooding in northwestern Pakistan was the worst since 1929, officials said.
4. El Nino to La Nina transition
Spring 2010 saw an enormous swing from El Nino to La Nina. Flooding in Indonesia, Colombia and Australia has all been tied to this phenomenon.
They are associated with opposite extremes in sea-surface temperature across the Pacific, and with opposite extremes in rainfall, surface air pressure, and atmospheric circulation from Indonesia to South America (approximately half the distance around the globe).
5. Negative Arctic Oscillation
The Arctic Oscillation influences winter weather in the Northern Hemisphere: when it is negative, arctic air slides south. In February, the index reached -4.27, the lowest value since records began in 1950.
6. Brazilian drought
A severe drought parching northern Brazil shrunk the Rio Negro (Black river) ? one of the most important tributaries of the Amazon River ? to its lowest level in over a century. At their point of confluence, the Amazon?s depth fell more than 12 feet below its average.
Nearly half of Amazonia?s 62 municipalities declared a state of emergency. The drought affected over 60,000 families.
7. (tie) Northeast Pacific hurricane (non-)season
The Northeast Pacific Hurricane Season was one of the least active on record. This dud of a hurricane season produced the fewest named storms and hurricanes of the modern era and had the earliest cessation of tropical activity ? Sep 23 ? on record.
7. (tie) Historic snow retreat
December 2009 had the second-largest snow cover of the satellite record (since the mid-1960s), followed by a ferocious spring snowmelt season. The rapidly melting snow contributed to spring floods across the Northern US and Canada.
Following the early and pronounced snow melt, the North American, Eurasian, and Hemispheric snow cover was the smallest on record for May and June 2010.
9. Shrinking Arctic sea ice
Arctic sea ice, the floating ice sheet that covers most of the Arctic ocean, shrunk to its third?smallest extent ever, measuring only 4.9 million sq. km. The last four years (2007?2010) are the four smallest on record.
For the first time in modern history, the Northwest Passage and the Northern (Northeast Passage) Sea Route were simultaneously ice-free in September.
10. China drought
A persistent drought, described as the worst in a century, covered parts of southern, southwestern and central China from January through April.
Centered in Yunnan province, the drought destroyed several million hectares of crops and dried up drinking water sources, affecting over 50 million people.