Global weather events in 2010

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 more than 50 million people, said the Office of State Flood Control and Drought Relief Headquarters.
Rains in late March and April eased the drought in most areas, so by the beginning of May, China declared the drought emergency over.

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 (1.9 sq. miles). 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 Sea Route were simultaneously ice-free in September.
Arctic ice shrinks every summer and grows every winter, but this summer, it shrunk at the fastest rate ever measured – more than 50 percent faster than average, and breaking the 1999 record.

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 more than a century. At their point of confluence, the Amazon's depth fell more than 12 feet below its average.
In the jungle city of Manaus, where the Black River merges with the Amazon and it should be at its deepest, its depth fell to 45 feet (13.6 meters) in October, the shallowest it has been since records began in 1902. Local authorities reported that nearly half of Amazonia's 62 municipalities declared a state of emergency. The drought conditions affected more than 60,000 families.

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.
During February's record oscillation, high pressure over the Arctic and low pressure at mid-latitudes drove freezing air into North America and Europe, resulting in heavy snowfall and record low temperatures.

El Niño to La Niña transition

Spring 2010 saw an enormous swing from El Niño to La Niña. Flooding in Indonesia, Colombia, and Australia has all been tied to this phenomenon.
El Niño and La Niña represent opposite extremes in the naturally occurring climate cycle referred to as the El Niño/Southern Oscillation (ENSO). 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).
Only 1973, 1983, and 1998 have seen larger within-year swings than 2010.

Flooding in Pakistan

Monsoon rains fall in Pakistan every summer, but the rains in June and July 2010 were unusually heavy, bringing more than a foot of rain. By Aug. 1, whole villages had washed away, more than 1,600 people had died, 6 million had lost their homes, and about 20 million people were affected, according to news reports. A shortage of safe drinking water and a possible outbreak of cholera were among the most pressing dangers.
The flooding in northwestern Pakistan was the worst since 1929, officials said. Just in the first week, news reports documented some 30,000 residents stranded on rooftops, and dozens of bridges completely washed away. Some estimates placed total damages from the flooding at US $15 billion.

Warmest year on record (probably)

According to NOAA, the globally-averaged temperature for 2010 will finish among the two warmest, and likely the warmest, in the 130-year-long 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.)
Three months in 2010 were the warmest on record for that month.
2001-2010 is the warmest 10-year period since the beginning of weather records in 1850, the UN weather agency announced on Dec. 2.

Russian-European-Asian heat waves

The heat waves of summer 2010 spawned drought, wildfires, and crop failures across western Russia, where more than 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 8 to 12 degrees F (4 to 8 degrees C) above average in Russia during June and July. On July 30th, Moscow recorded its highest temperature ever – 102 degrees F (39 degrees C) – breaking the previous record of 99 degrees F (37 degrees C) set just four days earlier. Prior to July 2010, the record hadn't been broken for 90 years.
The worst drought conditions since 1972 destroyed 22 million acres (nine million hectares), an estimated 20 percent of the nation's crops, including grain, vegetable, and fodder, prompting Russia to ban exports. Additionally, a state of emergency was declared as 948 forest fires covering 64,000 acres (26,000 hectares) were burning in 18 provinces.
The heat reached into Europe, too: on July 30th, the temperature in Joensuu, Finland reached 99 degrees F (37 degrees C), breaking Finland's all-time maximum temperature, 95 degrees F (35 degrees C), set in July 1914.
From The Christian Science Monitor