The Independent/UK

04 October 2006

The Century of Drought

One third of the planet will be desert by the year 2100, say climate

experts in the most dire warning yet of the effects of global warming

By Michael McCarthy, Environmental Editor

Drought threatening the lives of millions will spread across half the

land surface of the Earth in the coming century because of global

warming, according to new predictions from Britain's leading climate

scientists.

Extreme drought, in which agriculture is in effect impossible, will

affect about a third of the planet, according to the study from the

Met Office's Hadley Centre for Climate Prediction and Research.

It is one of the most dire forecasts so far of the potential effects

of rising temperatures around the world - yet it may be an

underestimation, the scientists involved said yesterday.

The findings, released at the Climate Clinic at the Conservative

Party conference in Bournemouth, drew astonished and dismayed

reactions from aid agencies and development specialists, who fear

that the poor of developing countries will be worst hit.

"This is genuinely terrifying," said Andrew Pendleton of Christian

Aid. "It is a death sentence for many millions of people. It will

mean migration off the land at levels we have not seen before, and at

levels poor countries cannot cope with."

One of Britain's leading experts on the effects of climate change on

the developing countries, Andrew Simms from the New Economics

Foundation, said: "There's almost no aspect of life in the developing

countries that these predictions don't undermine - the ability to

grow food, the ability to have a safe sanitation system, the

availability of water. For hundreds of millions of people for whom

getting through the day is already a struggle, this is going to push

them over the precipice."

The findings represent the first time that the threat of increased

drought from climate change has been quantified with a supercomputer

climate model such as the one operated by the Hadley Centre.

Their impact is likely to even greater because the findings may be an

underestimate. The study did not include potential effects on drought

from global-warming-induced changes to the Earth's carbon cycle.

In one unpublished Met Office study, when the carbon cycle effects

are included, future drought is even worse.

The results are regarded as most valid at the global level, but the

clear implication is that the parts of the world already stricken by

drought, such as Africa, will be the places where the projected

increase will have the most severe effects.

The study, by Eleanor Burke and two Hadley Centre colleagues, models

how a measure of drought known as the Palmer Drought Severity Index

(PDSI) is likely to increase globally during the coming century with

predicted changes in rainfall and heat around the world because of

climate change. It shows the PDSI figure for moderate drought,

currently at 25 per cent of the Earth's surface, rising to 50 per

cent by 2100, the figure for severe drought, currently at about 8 per

cent, rising to 40 cent, and the figure for extreme drought,

currently 3 per cent, rising to 30 per cent.

Senior Met Office scientists are sensitive about the study, funded by

the Department for Environment, Food and Rural Affairs, stressing it

contains uncertainties: there is only one climate model involved, one

future scenario for emissions of greenhouse gases (a moderate-to-high

one) and one drought index. Nevertheless, the result is

"significant", according to Vicky Pope, the head of the Hadley

Centre's climate programme. Further work would now be taking place to

try to assess the potential risk of different levels of drought in

different places, she said.

The full study - Modelling the Recent Evolution of Global Drought and

Projections for the 21st Century with the Hadley Centre Climate Model

- will be published later this month in The Journal of

Hydrometeorology .

It will be widely publicised by the British Government at the

negotiations in Nairobi in November on a successor to the Kyoto

climate treaty. But a preview of it was given by Dr Burke in a

presentation to the Climate Clinic, which was formed by environmental

groups, with The Independent as media partner, to press politicians

for tougher action on climate change. The Climate Clinic has been in

operation at all the party conferences.

While the study will be seen as a cause for great concern, it is the

figure for the increase in extreme drought that some observers find

most frightening.

"We're talking about 30 per cent of the world's land surface becoming

essentially uninhabitable in terms of agricultural production in the

space of a few decades," Mark Lynas, the author of High Tide, the

first major account of the visible effects of global warming around

the world, said. "These are parts of the world where hundreds of

millions of people will no longer be able to feed themselves."

Mr Pendleton said: "This means you're talking about any form of

development going straight out of the window. The vast majority of

poor people in the developing world are small-scale farmers who...

rely on rain."

A glimpse of what lies ahead

The sun beats down across northern Kenya's Rift Valley, turning brown

what was once green. Farmers and nomadic herders are waiting with

bated breath for the arrival of the "short" rains - a few weeks of

intense rainfall that will ensure their crops grow and their cattle

can eat.

The short rains are due in the next month. Last year they never came;

large swaths of the Horn of Africa stayed brown. From Ethiopia and

Eritrea, through Somalia and down into Tanzania, 11 million people

were at risk of hunger.

This devastating image of a drought-ravaged region offers a glimpse

of what lies ahead for large parts of the planet as global warming

takes hold.

In Kenya, the animals died first. The nomadic herders' one source of

sustenance and income - their cattle - perished with nothing to eat

and nothing to drink. Bleached skeletons of cows and goats littered

the barren landscape.

The number of food emergencies in Africa each year has almost tripled

since the 1980s. Across sub-Saharan Africa, one in three people is

under-nourished. Poor governance has played a part.

Pastoralist communities suffer most, rather than farmers and urban

dwellers. Nomadic herders will walk for weeks to find a water hole or

riverbed. As resources dwindle, fighting between tribes over scarce

resources becomes common.

One of the most critical issues is under-investment in pastoralist

areas. Here, roads are rare, schools and hospitals almost

non-existent.

Nomadic herders in Turkana, northern Kenya, who saw their cattle die

last year, are making adjustments to their way of life. When

charities offerednew cattle, they said no. Instead, they asked for

donkeys and camels - animals more likely to survive hard times.

Pastoralists have little other than their animals to rely on. But

projects which provide them with money to buy food elsewhere have

proved effective, in the short term at least.