Nov 23, 2017 the sahel is prone to climate stressors such as droughts, winds and floods. From a climatic point of view the west african region is defined by the mutual. Increased cmi cv often occurs along the interfaces between humid and dry, for instance, in the sahelian region of africa and in the north american great plains. This study on sahel climate, climate variability and climate change summarises what we currently know about present and future climate over the sahel region. Effect of the availability and natural resources management on the productivity and agricultural production poor rainfall, land degradation, insufficient use of mineral and organic fertilizers, the underequipment, land overexploitation, overgrazing, inadequate. Sahel synonyms, sahel pronunciation, sahel translation, english dictionary definition of sahel.
Since the 1960s it has been afflicted by prolonged periods of extensive drought. Adverse effects of climate change means changes in the physical environment or biota. Sudanian climate annual rainfall ranging from 600 mm to mm and. Climate models suggest soilmoisture feedbacks on time scales of days are relatively strong in the sahel 1, a fact supported by observational evidence 6,7. Shift in statistical properties of the climate system considered over long periods of time. It depends not only on a systems sensitivity but also on its ability to adapt to new climatic conditions ipcc, 1995 is consistent with the approach above, if we take extent quantitatively. The earths atmosphere is a complex dynamical, physical, and chemical system. General note article is recommended to print as color version in recycled paper. Sealing, crusting and hardsetting soils in sahelian.
Discover an az glossary of concise scientific explanations to help readers better understand climate change from science to solutions. Jun 12, 2011 climate models suggest soilmoisture feedbacks on time scales of days are relatively strong in the sahel 1, a fact supported by observational evidence 6,7. Climate change in the sahel centre regional agrhymet. Sahelian definition of sahelian by the free dictionary. Trend analysis of drought in the guinea and sudanosahelian. A changing climate, massive declines in biodiversity, and the depletion of land and freshwater resources pose serious threats to humankind. Frequency of sahelian storm initiation enhanced over. Rainfall in the region is very low and irregular with an annual precipitation of 200600mm mainly during the mayseptember monsoon season. But to respond suitably to growing insecurity, it is important to look beyond a simplistic equation linking global warming and resource scarcity to outbreaks of violence. However, another dominant feature of the sahelian climate is the high temporal and spatial variability of precipitation.
The sahel, here defined as the portion of africa between 12n and 20n, is a. Dynamic processes cover a large range of scales from the microscopicscale. On interannual and decadal time scales, sahelian rainfall is known to be affected by a variety of regional and global sea surface temperature sst anomaly patterns. Sahel sticks out as one of the areas where the variation is most severe. The african sahel experienced a prolonged dry episode in the latter decades of the twentieth century, characterised by years in which annual rainfall totals were consistently below the long term.
Ousmane ndiaye the first part of this study addresses the predictability of seasonal rainfall totals in the sahel region of west africa. Desertification in the sahel vanderbilt university. We show that, when driven with observed sea surface. Climate change terms and definitions science and climate. A new approach for the sahel institute for global change. The climate is typically hot, sunny, dry and somewhat windy all year long. Sahel, semiarid region of western and northcentral africa extending from senegal eastward to sudan. Average monthly distribution of rainfall and temperature, 19812010. The objective of this note is to clarify the contribution of climate as a driver of environmental change specifically desertification in the sahel.
Climate change, land and resource governance, and violent extremism issue brief 2 conditions for land and resource conflict and, in some situations, the emergence of violent extremism. Was the devastation the result of human misuse of the land, was it the result of natural changes in climate, or was it the result of. Climate change stressors in the sahel springerlink. The climate and ecology, history, and political organization of sahelian countries are diverse. Weather and climate the structure of the atmosphere surrounding the earth is a gaseous envelope or atmosphere, held in place by the planets gravitational attraction. The mechanisms of change, recent past and future alike, are still debated, hence the uncertainty in regional climate change projections. Climate change adaptation in the sahel sciencedirect. Climate change and its impact have dominated international policy agendas and public attention in recent times. A qualitative study among farmers in the equatorial and sudano sahelian zones 54 world ossunep, 2010. All studies also agree that the african continent is the most affected by the ongoing and future climate.
Climate change, migration and conflict in the sahel 25 this broad definition encompasses different forms of migration, from traditional adaptation to chang. This paper responds to this gap in understanding, and identifies and characterizes the state of climate change adaptation in the sahel, documenting how adaptation as a response to climate change has evolved over time and space and explores the role of climatic and nonclimatic drivers in triggering adaptation actions. Sahelian synonyms, sahelian pronunciation, sahelian translation, english dictionary definition of sahelian. These include interhemispheric contrasts of sst folland et al. West africa sahel and club secretariat secretariat. Time preindustrial, 1980spresent space global climate, sahelian climate, local climate. During the hottest period, the average high temperatures are generally between 36 c 96. Definitions and effects of droughts emphasis is given to the spatial variability over a region and the effects of drought over the water consumption and use sectors, such as domestic, download fulltext pdf download fulltext pdf the causes, effects and challenges of sahelian droughts. In the case of climate change adaptation, a total of 317 possibly relevant publications were selected from the initial search. Does climate change drive landuse conflicts in the sahel. A system of subdivisions often adopted for the sahelian climate based on annual rainfall is as follows. Saharan climate in the north annual rainfall sahelian climate in the central part annual rainfall ranging from 200 mm to 600 mm. Normal climate variability situated in the western sahel, between the sahara desert to the north and coastal rainforests to the south, burkina faso and mali are intertropical countries marked by a sudano sahelian climate, and are prone to strong geographic variation in annual rainfall as presented in the table below. The main features of the rainfall climatology in west africa.
The climate in this region has been highlighted by clark et al. In this document, the sahel comprises of burkina faso, chad, the gambia, mali, mauritania, niger. Indicator name coefficient of variation for climate. The sahel meaning shore in arabic is commonly defined.
The sahel region1 represents a transition zone between the saharan desert and the wet climate of tropical africa. The sahel region is in subsaharan africa and is a transition zone between the arid sahara desert to the north and the tropical green forest to the south, covering a surface area of 5. Permament interstate committee for drought control in the sahel. The sahel has a tropical, hot steppe climate koppen climate classification bsh. Econometric study on the impact of rainfall variability on security in the sahel region. Pdf on mar 1, 2012, carlo buontempo and others published the climate of the. The sahelian drought that started in 1969 which lingered on till 1973 affected northern nigeria and the calamity have had tremendous socioeconomic impacts on the area where pressure on available resources is on the increase in the face of a fluctuating rainfall regime 6. The climate and ecology, history, and political organization of sahelian countries are diverse and dynamic raynaut et al. Climate is what you expect, weather is what you get.
Climate change, migration and conflict in the sahel. There are several key factors interfering with the relevance of the spi as a measure of how rainy is a season over the sahel. Climate change, drought and pastoralism in the sahel. Paleodata indicate rapid ice sheet destabilizations during the last deglaciation, which could lead to an underestimation of sea level rise, as suggested in recent publications. Annual rainfall across this region fell by between 20 and 30 per cent between the decades leading up to political independence for the sahelian nations 1930s to 1950s and the decades since 1970s to 1990s. This paper therefore attempts to quantify the effects of land use change in the last 30 yr on the climate of the western and central sahel. Climate change refers to significant changes in global temperature, precipitation, wind patterns and other measures of climate that occur over several decades or longer.
Recharge estimation of hard rock aquifers under sahelian climate conditions using water table fluctuation. The idea that climate change leads to violent conflicts in general can be regarded as a continuation or revised version of the malthusian concept of resource scarcity as a cause of. Analysis of teleconnections between avhrrbased sea. Development of selftraining manual on the unfccc and the protocol of kyoto. The sahel has experienced several drought periods in the past 500 years, however no available records show a drought as persistent and severe as the one that started in the 1960s nicholson 1978. Sahelian climate change adaptation best practices drylands. The african sahel provides the most dramatic example of multidecadal climate variability that has been quantitatively and directly measured. Historically, scholarly investigations of the sahel have revolved around three subjects. Climate change and conflict in the sahel 2 the complex nature of conflict in niger and burkina faso makes it clear that the role of climate change as a contributor to violence can only be understood in relation to other factors.
Having a semiarid climate, it stretches across the southcentral latitudes of northern africa between the atlantic ocean and the red sea. Increased climate variability indicates larger yeartoyear fluctuations, and hence, less predictability in the climate. In the central sahel, states are mobilising to combat the impact of climate change as way of reducing conflict. A new approach for the sahel summary the sahel has the capacity to be a massive disruptive force, stimulating fresh pressures of migration and extremism, unless it is addressed by a comprehensive plan of action. The focus on the security implications of climate change has helped to bring climate change to the realm of international policymaking by placing it as a key threat to state and global stability. Trend analysis of drought in the guinea and sudano. Apr 25, 2017 the sahelian climate is influenced by the dry harmattan winds as well as wind movements within the intertropical convergence zone.
Climate change, 2019, 519, 188199 publication license this work is licensed under a creative commons attribution 4. Relationship between natural resources and food security a. The current state of understanding of sahel climate. Many thousands of people died and many more suffered severe disruption of their lives in the severe phases of this drought e. West africa sahel and club secretariat secretariat sahelian. A major uncertainty concerning the 21st century climate is the ice sheet response to global warming. Consequences of rapid ice sheet melting on the sahelian. Often climate indices are used to relate sahelian vegetation variability to largescale oceanatmosphere phenomena. The sahels climate is similar to, but less extreme than, the climate of the sahara desert located just to the north. A global perspective on african climate in climatic change. A quantitative evaluation of the multiple narratives of the. Research article 519, july september, 2019 climate. This means that a we focus on the mechanisms of rainfall variations at different scales. Feb 25, 2015 the climate is very hot yearround and the sahel doesnt normally know the cold.
Recharge estimation of hard rock aquifers under sahelian. The most notorious feature of the sahelian climate is the recent drought that struck the region starting at the end of the 1960s. Csa techniques summary of advantages and constraints 118 annex 11. There is a ticking time bomb waiting to go off in the sahel. It is here that the impacts of climate change are considered the most serious ipcc, 1998. The ipcc definition of vulnerability as the extent to which climate may damage or harm a system. Therefore, we explore the impact of different scenarios of greenland partial melting in the very sensitive sahel. The g5 countries comprised of burkina faso, chad, mali, mauritania. The sahel is prone to climate stressors such as droughts, winds and floods. The plot is based on cru data mitchell and jones, 2005. For example, category five should be expanded to include. Regional climate models rcm, and the second category should include. West africa sahel and club secretariat secretariat security.
605 1377 1463 1205 313 1004 373 1290 1491 577 205 65 114 1552 793 607 1051 47 196 1315 51 1417 714 1222 209 1612 805 633 1179 298 1112 1070 1416 1568 401 221 1038 1115 1461 1240 1298 279