
Long periods of drought can have devastatating effects on environment, agriculture, health and the economy. Droughts have also led to mass migration in several parts of the world.
Here's a look at the destruction caused by droughts across the world...
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A boat is seen stranded on the cracked bed of a dried area of Xieshan, which is part of Poyang Lake in east China's Jiangxi Province May 4, 2011.
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A dead alligator lies in a drying lake that forms part of the Amazon river system, near the city of Manaquiri, Brazil, November 22, 2009.
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A boy walks on the dried-up riverbed of the Yangtze River in Wanzhou, southwestern China's Chongqing municipality, August 28, 2006.
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A shoe lies on the dry bottom of the Barrios de Luna reservoir in the northern Spanish province of Leon February 14, 2008.
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A local resident walks on a dried-up riverbed at Huangyangchuan reservoir in Lanzhou, Gansu province, China, July 16, 2009.
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A boy leads his cattle to a partially dried-up pond on the outskirts of Yingtan, Jiangxi province, China, November 7, 2009.
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A yellow flower is seen in the bed of a dried-up pond on the outskirts of Kunming, southwest China's Yunnan province July 8, 2007.
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A Sudanese refugee rides his donkey at dusk as he crosses a dry riverbed near Bredjing camp in eastern Chad August 4, 2004.
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A farmer walks on a dried-up pond on the outskirts of Baokang, central China's Hubei province, June 10, 2007.
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An Indian farmer walks with his hungry cow through a parched paddy field in Agartala, capital city of India's northeastern state of Tripura, March 10, 2005.
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A farmer's hat lies on the dried-up bed of an irrigation canal leading from Honghu Lake, near Honghu city in central China's Hubei province, May 29, 2011.
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A farmer digs up roots of plants for firewood in a dried-up river bed at the base of the Wangkuai Dam wall in the village of Zhengjiazhuang in Hebei Province, located around 160 km (100 miles) south of Beijing January 16, 2008.
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A farmer works on a drought-hit paddy field in the outskirts of Chongqing municipality, China, March 24, 2009.
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A gumboot sits atop a fencepost on the site of the old town of Adaminaby as it re-emerges out of Lake Eucumbene, located 150 km (93 miles) south of the Australian capital Canberra June 5, 2007.
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People roll and drag water containers in Wajir, Kenya, in this recently taken handout photo released on July 21, 2011.
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A dead fish lies on the cracked earth of the drought-stricken La Sorrueda reservoir near Santa Lucia village, at the Spain's Canary island of Gran Canaria, March 22, 2012.

A dry tree branch lies on the cracked earth of the drought-stricken Entrepenas reservoir in central Spain August 11, 2006.
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The carcass of a cow lie on a roadside in Rift Valley town of Kajiado, 75 km (47 miles) south of the Kenyan capital of Nairobi, March 25, 2009.
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A farmer carries pails to transport water from a partially dried-up pond at the outskirts of Yingtan, Jiangxi province, China, February 5, 2009.
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The 70-year-old Sunken cemetery is seen after the Jablanicko lake dried up near Jablanica, Bosnia and Herzegovina, February 1, 2012.
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A family carry containers as they walk on a partially dried-up reservoir to collect water in Kaiyang county, Guizhou province, March 16, 2010.
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Footprints mark the bank of a partially dried-up pond near downtown Dallas, Texas August 1, 2011.
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Girls play in a deserted boat on a dry lake caused by a lack of water upstream in Zhengzhou, Henan province, China, February 12, 2009.
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The sun sets over a dry patch of land in Parras de La Fuente in the state of Coahuila, Mexico, November 24, 2011.