At least 35,000 people died as a result of the record heatwave that scorched Europe in August 2003, says an environmental think tank.

The Earth Policy Institute (EPI), based in Washington DC, warns that such deaths are likely to increase, as "even more extreme weather events lie ahead".

The EPI calculated the huge death toll from the eight western European countries with data available. "Since reports are not yet available for all European countries, the total heat death toll for the continent is likely to be substantially larger," it says in a statement.

France suffered the worst losses, with 14,802 people dying from causes attributable to the blistering heat. This is "more than 19 times the death toll from the SARS epidemic worldwide", notes the EPI.

Silent killer

August 2003 was the hottest August on record in the northern hemisphere. But projections by the Intergovernmental Panel on Climate Change predict more erratic weather, the EPI notes. By the end of this century, the average world temperature is projected to climb by 1.4 to 5.8°C.

"Though heat waves rarely are given adequate attention, they claim more lives each year than floods, tornadoes, and hurricanes combined," warns the EPI. "Heat waves are a silent killer, mostly affecting the elderly, the very young, or the chronically ill."

The searing August heat claimed about 7000 lives in Germany, nearly 4200 lives in both Spain and Italy. Over 2000 people died in the UK, with the country recording is first ever temperature over 100° Fahrenheit on 10^th August.

Cooling mechanisms

High temperatures are well known to result in a rise in deaths, as is cold weather. When the body is subjected to extreme heat, it struggles to maintain its ideal temperature of 37°C. The body attempts to do this by sweating and pumping blood closer to the skin, but high heat and humidity can confound these cooling mechanisms.

If the internal body temperature rises above 40°C, vital organs are at risk and if the body cannot be cooled, death follows.

Over the last 25 years, the average global temperature has risen by 0.6°C. The World Meteorological Organization estimates that the number of heat-related deaths could double in less than 20 years.

The EPI says it is confident that the August heatwave has broken all records for heat-related deaths and says the world must cut the carbon dioxide emissions that contribute to global warming.

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