Drought


 * What is Drought?**

Area suffers from drought when there hasn't rain as much as usually. Drought occurs all over the world and it is a serious problem. United Nations and other organizations try to help areas which suffer from drought.

Droughts are usual in areas where seldom rains. It has been warned, by UN, for example, that the Global warning will cause draughts. Also erosion and deforestation, usually caused by humans, are common reasons to drought.
 * Causes**:

The effects of drought varies about the time of drought. Eaven short period of drought has a huge impact on local enviroment and agriculture. Long period of drought might have many different consequenses to the enviroment: -Many species might might be exticncted when the enviroment changes -Many other natural disasters might be caused by drought (like dust storms, dust bowls and wildfires) -Geopolitical effects (such as wars over natural resources and social unrest) -Huge impact to the ecosystem and to the agiculture
 * Consequenses**:


 * Types of drought**

Drought is usually classified in three ways:

1. Meteorological drought takes place when in some area has rained less than normally in prolonged period. Meteorological drought usually leads to other kinds of drought. 2. Agricultural droughts are droughts which harm crop production and the whole agriculture. It usually occurs same way like a meteorological drought. In addition, agricultural drought can also arise independently if the level of precipitation changes and it damages soil conditions and launches an erosion. 3. Hydrological drought happens when the water reserves available sources are lower than statistical average.



http://en.wikipedia.org/wiki/Drought http://www.unccd.int/main.php http://www.bom.gov.au/climate/drought/livedrought.shtml http://classic-web.archive.org/web/20070819200515/http://www.peopleandplanet.net/pdoc.php?id=3024 http://www.dailyestimate.com/article.asp?idcategory=35&idSub=175&idArticle=12286 http://www.commondreams.org/headlines06/0717-07.htm
 * Sources:**

Made by: Mikko and Taneli