Climate extremes

Many scientists have warned that environmental changes are likely to be speeding up, climate extremes and disasters will come faster than expected. The hottest, coldest, wettest, driest, deadliest and unprecedented records of climate extremes till 2010 may easily be broken in 2011!

Extremes of climate have happened more frequently and over a greater part of the world over recent years, especially pronounced in 2009 and 2010. The bushfires and a record number of high-temperature days in the US; the unprecedented record heatwave and wildfires in the Russian Federation; the calving of a large iceberg from the calving from the Petermann Glacier in northern Greenland ice sheet; the concurrent incidences of drought and flood in China, Australia, are concrete manifestations of climate extremes.

Climate extremes

Early 2010 saw more frequent climate extreme occurrences. Whilst unusually intense snowstorms slammed the Republic of Korea, India, west Europe and the US; floods ravaged across Australia, Brazil, the Philippines, Bangladesh and Kenya. A once-in-a-century drought in China has brought water scarcity plights to 20 million people. Agriculture products have been severely affected with output reduced by 50%. Economic loss is estimated at USD2.8 billion.
(A rare drought in Yunnan of China in early 2010)

The annual Red Cross report showed a rise in weather-related disasters worldwide over the last decade:

  • from around 200 a year in the 1990s to around 350 at present. The report warned that extreme-weather events would become more frequent and more severe in the coming years.

After being exposed to the mercy of the century’s worst drought came the rainy season in many of the same areas. Strong rainstorms caused the collapse of reservoirs, overflowing of rivers, landslides, power failures and damage of highways. The Xinhua Press reported that, as at June the floods in China in year 2010 have affected 68.7 million people in 22 regions with death toll of 379 and 141 missing. 4.36 million hectares of farmland had been inundated, causing direct economic losses of USD 12 billion.

The occurrence of all these events at almost the same time raises questions about their possible linkages to the predicted increase in intensity and frequency of extreme events, for example, as stipulated in the Fourth Assessment Report of the IPCC published in 2007.

Projections made in the Fourth Assessment Report of the IPCC on

Change in extreme events since 1950:

An increase in the number of heat waves and warm days/nights and a decrease in the number of cold days/nights.
Widespread drying over much of Northern Hemisphere land areas. This is associated with initial precipitation decrease related to ENSO, land and sea surface warming
An increase in the number of heavy snow and heavy rain leading to snow disaster and flooding respectively, but not everywhere.
An increase in the maximum and minimum temperatures.
Less number of frost days associated with the average warming in most mid-latitude regions.
A substantial increase in intensity and duration of tropical storms and hurricanes. Changes are masked by large natural variability. The El Nino Southern Oscillation greatly affects the location and activity of tropical storms around the world. Activity is strongly correlated with higher tropical sea surface temperatures.
75% increase in the number of category 4 and 5 hurricanes since 1970 with decrease in the total number of cyclones and total number of cyclone days

An above-normal increase of hurricanes in the North Atlantic with 2005 as the record breaking year.