Research Highlights

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  • Earth & environment

Published online: 3 June 2009 | doi:10.1038/nchina.2009.121

Climate science: Desert on the move

Felix Cheung

Introduction

© (2009) istockphoto.com/David Ciemny

In China, arid or semiarid areas make up more than a quarter of the country's territory. Most of these areas are sand dunes, sand sheets or desert steppes where rainfall is erratic. Xunming Wang at the Chinese Academy of Sciences in Lanzhou and co-workers¹ have now simulated the potential dune activity and desertification trends in China in the twenty-first century. Their results show that desertification is likely to worsen from 2040 onwards because of global warming, placing the nearly 80 million people (about five times the population of Beijing) who live in these areas at risk.

The researchers used a dune mobility index, simulations based on five global climate models — including HadCM3 and ECHAM4 — and a range of published Intergovernmental Panel on Climate Change (IPCC) emission scenarios to evaluate the responses of dune activity and desertification in China to global warming. HadCM3-based simulations showed that desertification would decrease in most western regions of arid and semiarid China from 2010 to 2039, but would increase after 2040 to 2099. ECHAM4-based simulations showed that desertification would increase from 2010 to 2099.

A difference in precipitation was the main reason for the discrepancy between the two sets of simulations; the rainfall estimated by HadCM3 was 20–30% more than that predicted by ECHAM4. However, both models indicate that evaporation and transpiration are set to increase markedly in most regions of arid and semiarid China after 2040. This extensive desertification in the western and eastern regions would lower livestock and grain yields, and possibly threaten China's food security.

The authors of this work are from:
Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, China; Center for Arid Environment and Paleoclimate Research (CAEP), MOE Key Laboratory of West China's Environmental Systems, Lanzhou University, Lanzhou, China; College of Atmospheric Science, Lanzhou University, Lanzhou, China.

Reference

1. Wang, X., Yang, Y., Dong, Z. & Zhang, C. Responses of dune activity and desertification in China to global warming in the twenty-first century. Global Planet. Change 67, 167–185 (2009).
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