Parched parts of Earth expanding

By 2100, drylands will cover more than half of Earth's land surface, new climate projections show

DRYING OUT Arid drylands like this one are expected to cover more than half of Earth's land surface by the end of the century.

Haipeng Yu

By Chris Samoray

October 27, 2015 at 2:23 pm

Arid, hardscrabble landscapes could cover more than half of Earth’s land surface by 2100, a new study finds.

The expansion of drylands — fragile regions where vegetation is sparse and soil is fairly infertile — will predominantly occur in developing countries, according to new climate change simulations published October 26 in Nature Climate Change. That’s also where the greatest population growth is expected. More humans will mean a greater need for food and farming, which could further degrade and expand dryland environments, say Jianping Huang of Lanzhou University in China and colleagues.

Currently, drylands make up about 40 percent of Earth’s land surface.

Mapping a drying planet

Using new climate change simulations, researchers mapped global changes in aridity (map shows predicted change between 2071 and 2100 relative to a baseline period between 1961 and 1990, shown in gray). The greatest percentage of global land area that will become more arid is in developing nations, the simulations show (bar graph).

J. Huang et al/Nature Climate Change 2015

Editor’s Note: This story was updated October 28, 2015, to correct a typo in the deck — the climate change projection was for 2100, not 2010 — and to clarify that drylands are projected to cover more than half of Earth’s land surface, not more than half the planet.