19 August 2007

Asia: The heat of the moment

Sorry for the cheesy 80s song reference. I couldn't help myself!

Floods have ravaged Asia in 2007.

The floods have left millions homeless in India, Bangladesh and Nepal. But are the rains exceptional, and a product of global warming? Climatologists point out that until the last days of July, this summer's monsoon had been weak, with fears of crop failure due to drought rather than flood. Nevertheless, in general, global warming is adding to river flows by melting the glaciers of the Himalayas.

Several tropical cyclones have been noted, including

Super Typhoon Sepat came ashore in Taiwan on August 17, 2007, after bringing torrential rain and flooding to the Philippines the day before. ... The typhoon was classified as Category Five typhoon...with sustained winds of 184 kilometers per hour (114 miles per hour), according to CNN.

Japan has had a tough season thus far. In July came super-typhoon Man-Yi, the worst storm to hit Japan since records began in 1951. and simultaneously, a large (~7.0) earthquake which damaged a nuclear plant. Now they are having an extended heatwave and difficulty meeting the associated increase in power demand.

None of these individual events can be explicitly shown to have been caused by anthropogenic. They are merely data points in the ongoing sample needed to statistically verify what your senses and your instinct are already telling you—things are changing; the weather is different.

The strongest climate forcings are those produced by humans, including the anthropogenic increase of CO2 from the burning of fossil fuels, other byproducts of our civilization like ozone or other pollution and changes brought about from modifications to the land surface. Recent news items indicate that these are apparent in Asia

Siberia is experiencing earlier springs, a study of satellite images has revealed. The trend is likely to be triggering more forest fires, say researchers, and to be linked to global warming.

Satellite pictures over much of Asia and the Indian Ocean show an enormous brown stain hanging in the air - an unwanted byproduct of rapid economic growth which is having a curious effect on climate change and is affecting Australia.

Named The Asian Brown Cloud, it is made up of pollutants from woodfires, cars and factories, and scientists now believe it to be the reason glaciers in the Himalayas are melting.

A study...at the CSIRO recently suggested that the Asian haze might be actually increasing the rainfall in tropical Australia by changing the balance of temperature and circulation between Asia and Australia,"

This last item brings another facet to the manipulations in the cryosphere, another potential source of glacial melting. I've seen seminars regarding the Brown Cloud research. It is one possible link to the increased rainfall over NW Australia, particularly in summer. The basic idea is that the cooling in the pollution cloud displaces the region where the 'thermal equator' or ITCZ lies, changing the rainfall patterns on quite a broad scale.

CO2 forcing is real. Land-surface forcing is real. Regardless of the dominant mechanism at any given locale, the changes are primarily human induced. The solution is similar for either problem: live in an environmentally sustainable manner.

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