Research from Met Office (UK) scientists shows that an additional quarter of the earth's land surface could be affected by drought by the end of this century.

Dr Eleanor Burke, with colleagues from the Met Office Hadley Centre for Climate Change, has undertaken the first-ever projections of global drought, which was published yesterday (Thursday 26th October) in the Journal of Hydrometeorology.

Results show that areas under extreme drought could increase to 30 percent from today's figure of 3 percent and up to half of the land surface might be influenced by moderate drought at any one time.

The scientists have used a method known as the Palmer Drought Severity Index (PDSI) to calculate the extent of drought. This determines dryness from rainfall, evaporation and run-off.

Dr Burke's paper also concludes that human influence, through greenhouse gas emissions, is detected in the observed increase in global drought conditions during the period 1952-1998.

Speaking of her findings, Dr Burke said: "These results are very sobering but it must be pointed out that further research is required to substantiate what is the first look at this issue. However, it does indicate the potential seriousness of future climate change impacts if CO2 emissions continue to increase substantially."

The research shows that the climate model reproduces the global observed trend in drought very well, but is less good at capturing regional variations. Further research using other climate models from other Climate Centres is needed to substantiate these results and provide regional detail.

Drought poses a very real threat to business continuity. It can have many impacts, including:

1) The most obvious impact is upon businesses which rely upon industrial quantity water supplies for their day-to-day activities - agricultural and manufacturing companies for example. Such businesses are often seriously impacted by drought conditions in their regions.

2) Power shortages: in areas where hydroelectricity is an importance source of power generation, drought can result in power shortages and power rationing.

3) Increased risk of fire damage: perhaps the most wide-ranging impact of drought is the huge fire-risk increase it engenders. This not only creates a direct physical threat to businesses, but also to critical infrastructures upon which businesses depend.

4) Evacuations: whether linked to shortages of drinking, cooking and sanitation water, or to the increased fire risk, drought can lead to the requirement to evacuate away from affected areas, for potentially long periods of time. This can have a direct impact on businesses, with business premises becoming inaccessible; employees unable to travel to work; or employees having to take extended periods of absence to care for their own families and properties.