1 possible causes
1.1 environmental problems
1.2 demise of lake chad
1.2.1 ubangi river diversion proposal
1.3 possible effects of cash crops
1.4 over-population
1.5 aid workers being driven off kidnappers
possible causes
more century of rainfall data in sahel show unusually wet period 1950 until 1970 (positive index values), followed extremely dry years 1970 1990 (negative index values). 1990 until present rainfall returned levels below 1898–1993 average, year-to-year variability remains high.
map showing mean rainfall amount (mm) monsoon season (1 may – 30 september) in west africa. period 1995–2006. based on noaa/cpc climatology method rainfall estimates. africa rainfall climatology (cpc arc) series.
recent greening of sahel: results of trend analysis of time series on sahel region of seasonally integrated ndvi using noaa avhrr ndvi-data 1982 1999.
environmental problems
the western donor nations once theorised drought in sahel caused humans over-using natural resources in region through overgrazing, deforestation , poor land management. in late 1990s, climate model studies suggested large-scale climate changes triggers drought.
in 2000s, after phenomenon of global dimming discovered, speculatively suggested, drought caused air pollution generated in eurasia , north america. pollution changed properties of clouds on atlantic ocean, disturbing monsoons , shifting tropical rains southwards. global dimming, blocking of sunlight man-made particulates, has been identified 1 culprit decades-long drought across sub-saharan africa.
a 2006 study noaa scientists rong zhang , thomas l. delworth suggests atlantic multidecadal oscillation/(mao) plays leading role. amo warm phase strengthens summer rainfall on sahel, while cold phase reduces it. amo entered warm phase in 1995 and, assuming presence of theoretical 70-year cycle (following peaks in ≈1880 , ≈1950), peak around 2020.
the sahel’s farmers have been largely cleared of blame 20th century’s sahel droughts. sahel region’s droughts in 1970s , 1980s caused recent warming of indian ocean, rather over-farming causing environmental degradation assumed, according new joint scidev/un study. both 3.5 c. rise in niger s temperature on last decade , irrigated land accounting 0.1% of niger s inhabitable land, regular famine crisis inevitable in years. acute water shortages, common in region s harsh weather, make irrigation systems more important local farmers.
the demise of lake chad
the lake chad basin straddles borders of both niger, nigeria, cameroon , chad. lake situated 281 metres (922 ft) above sea level , diminishing on time due lack of rain water , major rivers running it. according un marshy lake shrank as 95% 1963 1998 yet state 2007 (satellite) image shows significant improvement on previous years . lake chad economically important, providing water more 20 million people living in 4 countries surround (chad, cameroon, niger, , nigeria) on edge of sahara desert. plant typha australis (or big cattail) cutting off water supplies in lake chad basin, , has slashed available water supplies in chad’s region. protected area lake chad game reserve, covers half of area next lake belongs nigeria. whole lake has been declared ramsar site of international importance.
the ubangi river diversion proposal
in 1960s, plan proposed divert ubangi river lake chad. copious amount of water ubangi revitalize dying lake chad , provide livelihood in fishing , enhanced agriculture tens of millions of central africans , sahelians. inter-basin water transfer schemes proposed in 1980s , 1990s nigerian engineer j. umolu (zcn scheme) , italian firm bonifica (transaqua scheme). in 1994, lake chad basin commission (lcbc) proposed similar project , @ march, 2008 summit, heads of state of lcbc member countries committed diversion project. in april, 2008, lcbc advertised request proposals world bank-funded feasibility study.
the possible effects of cash crops
cotton , groundnuts 2 of chad s 4 major cash crops. mali s major cash crops peanuts , cotton. mali s cotton production has grown 500,000 tonnes in 1997 record 635,000 tonnes in 2003, has pleased african association of cotton producers, has led claim cash crops being put before food , fodder crops in mali, burkina faso , chad. cassava production has fallen in burkina faso since 2007, relative cotton output. cash crops cotton, groundnuts, shea nuts, , sesame. sahel’s farmers largely cleared of blame 20th century’s sahel droughts, there enduring question of whether cash crops cotton more important food plants wheat , casava.
over-population
many of world s countries, including many in sub-saharan africa, middle east , south east asia, have seen sharp rise in population since end of cold war. fear high population numbers putting further strain on natural resources, food supplies, fuel supplies, employment, housing, etc.; in of less fortunate countries. population of chad has, example, grown 6,279,921 in 1993 10,329,208 in 2009, further straining resources. nigeria witnessing similar growth in population, strained resources , possible over-population problem in near future.
the situation acute in northern, western , central africa. refugees places sudan have helped further strain resources of neighboring states chad , egypt. nation host 255,000 refugees sudan’s darfur region, , 77,000 refugees central african republic, whilst approximately 188,000 chadians have been displaced own civil war , famines, have either fled either sudan, niger or, more recently, libya.
aid workers being driven off kidnappers
on 25 august french aid worker kidnapped in chad. kidnapping of foreigners along chad/darfur border became more frequent in 2009. french ngo worker taken , murdered on 29 october 2009, , unidentified red cross worker captured on 10 november 2009. many ngos , charities have begun restrict areas covered aid work in niger, chad, , sudan due ever-present risk of bandits , kidnappers. organizations pulling out in fear of workers lives.
most international aid agencies have been withdrawing workers areas of sahel, due regional kidnapping crisis. niger s government spokesman mahamane lawali danda told b.b.c. pullout surprise him since no 1 had told him or government niger on list of dangerous kidnapper infested pariah nations, along chad, darfur , sudan. strangely, mauritania , mali not on list of dangerous nations, despite several al-qaeda lead kidnappings in both during 2009.
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