Supercomputer simulations at the UK's Hadley Centre for Climate Prediction and Research forecast that 30% of Earth will be uninhabitable due to intense drought by 2100, compared with 3% at present. Half of the land surface will be in drought at some level if no action is taken to curb global warming. Andrew Pendleton of Christian Aid said, "This is genuinely terrifying, 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."

Severe drought has more than doubled globally since the 1970's bringing misery to millions in Africa. Eleven million nomadic herders from northern Kenya to Tanzania are now awaiting the short rains necessary to grow grasses vital to keep their herds alive. The rains never came last year. Drought in Texas has resulted in huge agricultural losses and persists in the mountain states of the U.S.

The Amazon rainforest with a third of Earth's plant and animal species is in drought for a second year due to global warming and deforestation. The very survival of tropical rain forests is in question. Researchers at Duke University using NASA climate models forecast global climate change resulting from the loss of Amazonia. Not only would South American climates be altered, but northern Mexico and Texas would lose moisture during the critical agricultural seasons of spring and summer. Loss of rainforests in Africa would bring drought to the central U.S.

Water
Hundreds of millions of people in the Himalayan and Andean countries are dependent to some extent on glacial melt water for personal use, agriculture, and hydropower. Precipitation falls mainly as rain rather than snow causing early spring runoff overwhelming manmade and ecosystem reservoirs. Rapidly melting glaciers will create hundreds of millions of ecorefugees seeking water on a planet half in moderate, severe, or intense drought by 2100. Wealthier countries are not exempt. The Alpine countries of Europe and the Rocky Mountain countries in North America will also lose glacial melt water resulting in economic and environmental crises.

Food
As a rule of thumb, every degree centigrade rise in global temperature lowers agricultural output by 10%. Rising temperatures cause evaporation rates to increase lowering soil moisture. Water tables fall and aquifers become depleted as farmers drill deeper for water. World food stocks have dropped to a new 57 day low from 116 days in 1999. For 6 out of the past 7 years not enough food has been produced to feed humanity. Food prices have risen 20% in the past year as competition from crops grown for biofuels grows. Enough corn is used to make ethanol for one SUV tankful as that which feeds a person for an entire year. In countries vulnerable to food shortages live 4.2 billion people. The United States once overflowing with surplus food is on the verge of becoming a net food importer.

Action
To prevent the spread of deserts and to secure global food and water supplies, it is necessary not only to bring greenhouse gases under control, but also to reduce population growth rates, use water more efficiently, conserve soils, and protect ecosystem services. Governments at all levels, industry, institutions, and individuals must engage in a massive effort within the next 10 years. You can personally take action by

1. Voting for candidates who will take vigorous and prompt action
2. Calling or writing your elected officials to voice your concerns
3. Taking public transportation
4. Driving a fuel efficient car
5. Heating your home with wood or biofuels
6. Choosing renewable electricity
7. Making your home energy efficient
8. Planting trees
9. Reducing consumption
10. Supporting family planning
11. Eating locally grown food

Let us not leave a parched and inhospitable planet to our children and grandchildren. Let us create a thriving, pollution-free, and sustainable world for all.