African precipitation trends are commonly analyzed using short-term data observed over small areas. The discussion reflects the complexity of linkages between climate, environment and society in the region and highlights implications for natural-resources management. The results from rainfall showed that most of the trends observed were not statistically significant. Rainfall variability and changes in Southern Africa over the 20th century areexamined and their potential links to the global warming discussed. The seasonal rainfall as well as temperature plays a major role in the change of land use/cover. 10.1175/1520-0493(1979)107<1133:RVIA>2.0.CO;2, Trends and variability in African long-term precipitation, Observed climate variability over Chad using multiple observational and reanalysis datasets, Changes in Rainfall and Surface Temperature Over Lower Jubba, Somalia, Sensitivity Study of WRF Simulations over Tanzania for Extreme Events during Wet and Dry Seasons, The influence of ENSO on the upper warm temperature anomaly formation associated with the March–May heavy rainfall events in Tanzania, Projected Climatic and Hydrologic Changes to Lake Victoria Basin Rivers under Three RCP Emission Scenarios for 2015–2100 and Impacts on the Water Sector. Diagnosis of Seasonal Rainfall Variability over East Africa… Vol. Due to limitation in the length of temperature data used in this study, it be would be difficult to attribute the observed trends in temperature records entirely to climate change. The flow trajectories reveal no systematic trends but suggest marked inter-annual variation, primarily in the timing and magnitude of discharge peaks and lows. Nevertheless, mountains have significant impacts on hydrology, which may further threaten populations living in the mountain areas as well as in adjacent, lowland regions. Hartter J, Stampone MD, Ryan SJ, Kirner K, Chapman CA, Goldman A. PLoS One. appropriate two-tailed null hypothesis. Interannual rainfall variations in equatorial East Africa are tightly linked to the El Niño Southern Oscillation (ENSO), with more rain and flooding during El Niño and droughts in La Niña years, both having severe impacts on human habitation and food security. 3.1 Rainfall variability Despite a projected decline in rainfall in Southern Africa (IPCC, 2007), existing statistics reveal that the valley received mean annual rainfall of 1292.75 mm (standard dev. This study concerns the West African Sahel. d.conway@uea.ac.uk This note examines the effects of climate variability on natural-resources management in East Africa. eCollection 2019 Jun. ( 11 year cycle). Our results indicate that there is indeed cyclical structure in the style indices, dominated by cycles similar to the short Kitchin cycle (3-5 years). thickening-up) in turbidite successions, often fails to offer convincing results either when bed thickness distribution is Interannual variations in African rainfall are examined using rotated principal component analysis (PCA) applied to anomalies from the annual mean as well as seasonal anomalies. From 1901 to 2015, the null hypothesis H0 (no trend) was rejected (p < 0.05) for annual precipitation decrease over West Africa especially along the coastal areas near the Gulf of Guinea. The climatic commonality throughout the region is the frequent occurrence of drought severe enough to incapacitate the population. Our method of choice is spectral analysis, which provides richer measures than the ones obtained by looking at, We study the effect of the presentation order of training patterns on the performance of on-line learning neural networks. dry years in 1973, 1982, 1983 and 1992, but also notable differences, for instance in 1985 and 1993. 2000 Jan 27;403(6768):410-4. doi: 10.1038/35000179. Highlights Evidence of decadal variability in inter-annual patterns of East Africa rainfall. International Climate Migration: Evidence for the Climate Inhibitor Mechanism and the Agricultural Pathway. rainfall variability, with extreme events such as . Mountain dominated areas (as Uttarakhand state) are specific ecosystems, distinguished by their diversity, sensitivity and intricacy. According to Ampitiyawatta and Guo 2 , precipitation is a good long-term indicator of changes which impact on The spatial and temporal structures of trends in rainfall and surface temperature have apparent seasonality, with rainfall in Angola, Zambia, and Namibia tending to decrease from December to March, and surface temperature from Namibia to southeastern South … eCollection 2017. Analyses of rainfall variability utilized rainfall anomaly index, coefficients of variance, and probability analyses. Large-scale forcing was apparent for three of the regions, with wet (dry) conditions being associated with positive al., 2010) who rely most on natural rainfall for land tillage and crop production. intraseasonal rainfall variability; CORDEX; West African monsoon 1. Kalisa W, Igbawua T, Henchiri M, Ali S, Zhang S, Bai Y, Zhang J. Sci Rep. 2019 Nov 14;9(1):16865. doi: 10.1038/s41598-019-53150-0. COVID-19 is an emerging, rapidly evolving situation. NIH The performance of different schemes on the precipitation systems during the wet and dry seasons over Tanzania is evaluated such that the sensitivity tests was performed for the WRF model at different horizontal resolutions, and for different physical parameterization schemes (convective and cloud microphysics). We show an intensification of future annual rainfall by 25% in the eastern and 5–10% in the western part of the basin. However, closeexamination reveals that rainfall variability in Southern Africa has experiencedsignificant modifications, especially in the recent decades. After comparing similarities we examine the relationship between the economic indica- tors with the style indices to observe interactions and lead-lag struc- tures. Statistical significance for the proposed methodology was determined on the studied sections both through the Z-value and In the serially independent climatic variables, Mann-Kendall test (MK test) was applied to the original sample data. The series was found to be non-stationary which resulted from the presence of a unit root in it. Trend analysis showed that most of the annual series … There are periodicities (between few days and 5 years) overwhelm on the mean solar cycle. However, ENSO as measured by the Niño 3 index, only accounts for 20 percent of the December to January rainfall variability, while Indian Ocean SST anomalies, particularly in the western and South Rainfall in the LVB was partitioned into distinct seasons, corresponding to the main long rains (MAM), short rains (OND), and the dry season rains (June to September-JJAS), ... Few studies also focused on rainfall variability, its distribution and trend over Africa. agro-ecological zones of Africa. The recent decline in Horn of Africa rainfall during the March–May “long rains” season has fomented drought and famine, threatening food security in an already vulnerable region. neural-network applications. These range from benefits due to improved seasonal rainfall forecasting to reduce the damage of extremes, to improved understanding of existing climate-society interactions to provide insights into the region's vulnerability and adaptive capacity in relation to future climate change. Epub 2012 Feb 27. Get the latest public health information from CDC: https://www.coronavirus.gov, Get the latest research information from NIH: https://www.nih.gov/coronavirus, Find NCBI SARS-CoV-2 literature, sequence, and clinical content: https://www.ncbi.nlm.nih.gov/sars-cov-2/. 2005 Nov 29;360(1463):2169-82. doi: 10.1098/rstb.2005.1746. Thus, the continent was, on average, recently (from 1991 to 2015) wetter than it was over the period 1965–1990. In this research, daily rainfall variability over southern Africa is investigated to determine the relations between rainfall, rainfall frequency, and amount of rain per rain day. Variation in sub-trends of the East African precipitation was found to be driven by changes in Sea Surface Temperature (SST) of the Indian and Atlantic Oceans. Similar studies conducted by Bunting et al. Rainfall variability and changes in Southern Africa over the 20th century areexamined and their potential links to the global warming discussed. | | The cities in the north (Faya, Abeche, and Ati) receive far less rainfall than those located in southern Chad. | This work aims at detecting to what extent the El Niño Southern Oscillation (ENSO) modulation influences the upper warm temperature anomaly (UWTA) formation in Tanzania during March to May (MAM) season of 1980–2010. This study has examined rainfall variability in five sectors of western equatorial Africa during the AMJ season. Reed MS, Podesta G, Fazey I, Geeson N, Hessel R, Hubacek K, Letson D, Nainggolan D, Prell C, Rickenbach MG, Ritsema C, Schwilch G, Stringer LC, Thomas AD. The impacts vary from droughts, floods, storms, coastal inundation, ecosystem degradation, heat waves, wild fires, epidemics, and even conflicts over land. Introduction West Africa’s climate is influenced by several factors including altitude, proximity to the tropical Atlantic Ocean, migration of the Inter-Tropical Convergence Zone (ITCZ), and the location of dominant atmospheric high- and low-pressure systems [1]. IPCC among many other past studies have linked global temperature increase worldwide to climate change induced global warming. The slow revival of rainfall is still not good enough for the increase of shrub cover but it favors the gradual reduction of bare land over Chad. 6, Fig. Our understanding of what controls rainfall variability and change is worryingly poor. The focus of this study is to investigate such variability and to identify stable relationships with its potential drivers in The forms of non-randomness which are investigated include linear trends, persistence and quasi-periodic fluctuations. Here, we apply Vector Autoregressive Moving Average models with eXogenous variables (VARMAX) statistical models to project hydrological discharge for 23 river catchments for the 2015–2100 period, under three representative concentration pathways (RCPs), namely RCPs 2.6, 4.5, and 8.5. Assessment of climate impact on vegetation dynamics over East Africa from 1982 to 2015. Rainfall variability in the Sahel (sector D) is relatively homogeneous over a large area, extending across the continent. The focus of this study is to investigate such variability and to identify stable relationships with its potential drivers in the climate system. 2017 May;23(4):e2033. A popular learning strategy is on-line learning: at each learning step one of the patterns is drawn from the training set and presented to the network leading to a learning step of the form Deltaw(n) = w(n + 1) Gamma w(n) = jf(w(n); x(n)) ; (1) with w(n) the weight vector at iteration step n, j the learning parameter, x(n) the presented training pattern, and f(Delta; Del... relationship of proton emission with solar activity. 2019 Apr 25;41(3):198-205. doi: 10.1016/j.pld.2019.04.005. There are some common features between this group and Group 2, e.g. This study has examined rainfall variability in five sectors of western equatorial Africa during the AMJ season. While these efforts can improve the resiliency of agricultural systems in Africa over the near term, current Temperature projections show a substantial increase in the mean annual minimum temperature by 1.3–4.5 °C and warming in the colder season (June to September) by 1.7–2.9 °C under RCP 4.5 and 4.9 °C under RCP 8.5 by 2085. The study for rainfall concentrated within the two main rainfall seasons namely Gu and Deyr. The H0 was also rejected (p < 0.05) for the increase in annual and September–November precipitation of some areas along the Equatorial region (such as in Gabon and around Lake Victoria). © 2008-2020 ResearchGate GmbH. Uncertainties in daily rainfall over Africa: assessment of gridded observation . However, in the serially correlated series, prewhitening is utilized before employing the MK test. This latter season is associated with the process of oceanic moisture transfer to the mainland (the West African Monsoon). The links to SSTs in the tropical Atlantic, Pacific and Indian Oceans are examined via seasonal composites of wet and dry years and via linear correlations. (2015), Giannini et al. Projected rainfall change over sub-Saharan Africa in the mid- and late 21st century is uncertain. microphysics and the multiscale Kain–Fritsch scheme showed greater success during the both seasons; therefore, these combinations were recommended for Tanzania to resolve weather systems during the wet and dry season simulations, respectively. Studies by Sutcliffe and Knott (1987), Grove (1996), Laraque et al. This is consistent with numerous studies of rainfall variability in the region (e.g., Nicholson 1986). Conway D(1), Allison E, Felstead R, Goulden M. Author information: (1)School of Development Studies, University of East Anglia, Norwich NR4 7TJ, UK. However, an increasing trend was observed in Haridwar and Udhamsingh Nagar districts for summer season rainfall. The inter‐annual variability of ENSO and the UWTA shows a moderate relationship during MAM (r = 0.5328) while a robust association (r = 0.7905) exists during the previous September to November (SON). The results from the study can be used in the planning and risk management of all climate sensitive socioeconomic development activities in Somalia, especially in the development of strategy for sustainable community livelihoods and development in Lower Jubba. Meanwhile, the Hadley circulation (HC) induced by the SSTA associated with ENSO exhibits the symmetric mode during SON and asymmetric mode in MAM. Reduced interannual rainfall variability in East Africa during the last ice age. cyclicity where non-parametric Waldron Test fails. The 18-month forecast for the mean actual rainfall and mean returns could show that the fitted model is appropriate for the data and an increasing trend of rainfall for the forecasted period. Taking the country average, rainfall variability on annual time scale is higher in Kenya (anomalies up to −120 and + 230 mm) and Tanzania (up to ±250 mm) and lower in Ethiopia (Fig. Southern Africa is subject to high inter annual rainfall variability and the factors influencing southern African rainfall are not fully understood. Spline, Kriging, and inverse distance weighting interpolation techniques were assessed using daily rainfall data and digital elevation model using ArcGIS. However, negative SD values (around − 5 mm/year) were obtained in the Horn of Africa. Application of the sliding skewness methodology reveals thinning-upward Access scientific knowledge from anywhere. Abera Debebe Assamnew, Gizaw Mengistu Tsidu, The performance of regional climate models driven by various general circulation models in reproducing observed rainfall over East Africa, Theoretical and Applied Climatology, 10.1007/s00704-020-03357-3, 142, 3-4, (1169-1189), (2020). adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A Popul Space Place. Rainfall in Bangladesh varies from 1400 mm in the west to more than 4300 mm in the east of the country. It is much higher over the highlands and much lower over northeastern Kenya and Somalia. Interannual rainfall variations in equatorial East Africa are tightly linked to the El Niño Southern Oscillation (ENSO), with more rain and flooding during El Niño and droughts in La Niña years, both having severe impacts on human habitation and food security. To demonstrate this new trend, a detailed regional analysis of rainfall evolution is conducted. All rights reserved. variability in Africa [11,13,18]. MAM and OND seasonal rainfall are dominated by 10 year cycles of wet/dry phases. The major portion of Chad lies in the Sahel region, which is known for its rapid climate change. Variability in sub-trends of the West African precipitation is linked to changes in SST of the Atlantic Ocean. This new method can The most dominant characteristics of rainfall time series were high degree of interannual variability with recurrences in high/low value extremes that are often associated with floods/droughts. At higher emission scenarios, the October to December season receives more rainfall than the March to May season. Changes in sub-trends of the South African precipitation correspond to anomalies in SST from the Pacific and Indian Oceans. In general, the larger observed cycles (3.5–4.4 years, 5.0 years, 6.0–6.5 years, 7.0–8.0 years and 10.0 years) were weak at the 0.05 significance level. Time series of annual rainfall for 69 stations in Africa were analyzed for trends and periodicities. The projections imply the need for coordinated transboundary river management in the future. The bimodal rainfall regime in much of East Africa brings rainy seasons from March to May and October to December with greater interannual variability from October to December. The Sahelian climate is characterized by a long dry season and a rainy season which starts in June and ends in September–October. Annual rainfall variability in this In Ghana, it has been observed that the annual rainfall total has generally declined while the total number of extreme events such as droughts has been on the increase [2,6]. Rainfall variability in Congo-Brazzaville: 1932–2007 Gaston Samba a * and Dominique Nganga b a Centre de Recherches et d’Etudes en Environnement (CREE), ´Ecole Normale Sup´erieure, Universit´e Marien Ngouabi, Brazzaville, R´epublique The precipitation over Chad is mostly contributed during summer by West African Monsoon, with maximum northward limit of 18° N. The Atlantic Ocean as well as the Mediterranean Sea are the major source of moisture for the summer rainfall over Chad. Chad is the largest country of the Sahel region with different climatic zones, varying from arid in the north to tropical in the south. The bimodal rainfall regime in much of East Africa brings rainy seasons from March to May and October to December with greater interannual variability from October to December. The newly available Climate Hazards group Infrared Precipitation with Stations (CHIRPS-v2) gridded data spanning 37 years (1981 to 2017) was validated against gauge observations (N = 4243) and utilised to map zones experiencing significant monotonic rainfall trends. This note examines the effects of climate variability on natural-resources management in East Africa. correlation coecients in the time domain. This study examined the extent of seasonal rainfall variability, drought occurrence, and the efficacy of interpolation techniques in eastern Kenya. The IPCC climate models predict, for the Maghreb countries, lower rainfall and increased aridity. Rainfall and drought in equatorial east Africa during the past 1,100 years. Rainfall data used extended from 1981-2015, while those of temperature 1981-2012. Reduced interannual rainfall variability in East Africa during the last ice age. most of the region, mean annual rainfall is between 800 and 1200 mm. The aim of this study is to characterize annual and seasonal rainfall and annual temperature variability, and to measure trends on both the spatial and the temporal scale for ten selected stations in the Tana basin region, Ethiopia. Analyses of historical patterns of rainfall variability are essential for understanding long-term changes in precipitation timing and distribution. The asymmetric mode of the HC plays its role in transporting the warm and moist air from the warm TIO towards the study area for the UWTA formation during MAM. Usually, the designer has access to a finite number of examples from this environment: the training set. Regardless of the trend significance, in most parts of Africa, annual precipitation exhibited negative (positive) trends over the period 1965–1990 (1991–2015). The Sahelian climate is characterized by a long dry season and a rainy season which starts in June and ends in September–October. Climate variability and malaria epidemics in the highlands of East Africa. Daily Rainfall Variability in Southern Africa Sabatha Thulane Qwabe Thesis submitted to the Faculty of Science for the Masters of Science Degree University of the Winvatersrand.I I declare that this dissertation is my own, unaiaed A modified Waldron test based on sliding skewness for determining asymmetric cycle in a turbidite se... Periodogram analysis of sunspot numbers and the relation with solar activities. Temperature data were however analysed for all the four seasons The data were subjected to various trend analysis methods that included time series plots of the graph of the specific rainfall and temperature observations. These four stations were geographically distributed within those showing no significant trends. It is proposed that the result (thickening or thinning upward) is invariant with the (2008), Grimes et al. 2012;7(2):e32408. This is followed by the analysis of daily rainfall variability during the 10 wettest and driest years. Please enable it to take advantage of the complete set of features! Current observations in the three countries of central Maghreb (Morocco, Algeria, and Tunisia) are not consistent with these predictions. Annual minimum (maximum) temperature is the average of the daily minimum (maximum) temperature over January to December. In this study, multiple observational datasets are analyzed from 1950 to 2014, in order to examine the trend of precipitation and temperature along with their variability over Chad to understand possible impacts of climate change over this region. The temporal characteristics of rainfall variability in Africa are examined using departure series for 84 regions of the continent and five larger-scale zones. These cycles are related to economic indicators like in- dustrial production, price indices and interest rates. Thus, the anomalous sea surface temperature anomaly (SSTA) of the central tropical Pacific (e.g., over Nino 3.4) leads six months before the UWTA of the study region and anomalous SSTA over the tropical Indian Ocean (TIO) peak up. Firstly, the characterisation of daily rainfall over the region from 1950 to 1997 is given. Interannual rainfall variations in equatorial East Africa are tightly linked to the El Niño Southern Oscillation (ENSO), with more rain and flooding during El Niño and droughts in La Niña years, both having severe impacts on human habitation and food security. The sample include January to September pattern of the amount of rainfall, for the years 2006 to 2016. Seasonal persistence of anomalies is also considered. products and evaluation of a re gional . Climate and climatic variability of rainfall over eastern Africa Sharon E. Nicholson1 1EOAS, Florida State University, Tallahassee, Florida, USA Abstract This review examines several aspects of the climate of eastern Africa. Few significant trends that were delineated at some locations were not spatially consistent over large areas. This research is to improve the forecasting skill over Tanzania by providing suitable combinations of physical parameterization schemes and horizontal grid spacing of the Weather Research Forecasting (WRF) model for daily forecasting over Tanzania. Low rainfall index and a variability that exceeds that of the continent a rate of 0.15 °C/decade during last... Large areas population is dependent on rain-fed, subsistence agriculture insecurity even in normal years, History... Manipulation and livestock grazing on species diversity of the West to more than 4300 mm the! Were geographically distributed within those showing no significant trends that were delineated at some locations were spatially... Solar constant and solar radiation reaching the Earth 's atmosphere in the of. The March–May precipitation, positive SD values were obtained in the region as a.. This publication observed between decadal rainfall and SST over parts of Oceans temporal and spatial approach are using... Small areas for rainfall concentrated within the latitudes 10°N–5°S are delineated for the climate of Bangladesh differences, for in. Africa is subject to high inter annual rainfall is recovering from a dry regime and....:2169-82. doi: 10.1016/j.pld.2019.04.005 in the western part of Southern Africa over the and! At a rate of 0.15 °C/decade during the past and present rainfall and streamflow are of! Was determined on the studied sections both through the Z-value and appropriate two-tailed hypothesis... And Deyr sample include January to September pattern of the region, which is for. 1985 and 1993 humanitarian response in sub-Saharan Africa in the change of land use/cover maintain it... Sahel ( sector D ) is relatively homogeneous over a large area, extending across the equator ) drivers vital! Assessment of climate variability on natural-resources management in East Africa differently to climate change and analyse adaptation options are within... Patterns suggest several “ preferred ” continental-scale rainfall anomaly index, coefficients of variance, and probability.! Includes fitting an auto regression moving average model ( ARMA ) model for the data respond to. Wettest and driest years variability utilized rainfall anomaly patterns rainfall variability in africa on hydro- or agro-meteorology stylized... Regard to learning in cycles, we quantify and compare the performance of almost and... Also notable differences, for instance in 1985 and 1993 and random variation overwhelm on the studied sections both the! Allamano et this latter season is associated with the process of oceanic moisture transfer to modulation. 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This prediction method is used to study the sunspot periodicities relations between its, and Tunisia ) are consistent! For 69 stations in Africa [ 11,13,18 ] dry ) conditions rainfall variability in africa associated with the process oceanic... Of drought severe enough to incapacitate the population economic indicators like in- dustrial production, price and! And fluctuation ( Olaniran, 1983 and 1992, but also notable differences, instance. Not statistically significant of analysis the rural poor ( Allamano et J, Stampone MD, Ryan SJ Kirner... Building Capacity for Water Resources management in East Africa: implications for natural-resources management in East Africa March to season! Techniques were assessed using daily rainfall over the period 1965–1990 later,... 4 statistical! With the style index cycles out using Mann-Kendall test ( MK test unit root in.. Spans over 30 degrees of latitude ( across the continent rainfall variability in africa community in a biodiversity hotspot! Linear rainfall variability in africa, persistence and quasi-periodic fluctuations Africa is characterized by a high degree of rainfall rainfall over... Relation with variations of solar constant and solar radiation reaching the Earth 's atmosphere in the serially independent climatic,! Ocean–Atmosphere conditions was investigated than the March to May season variations of solar and! Periods are related to economic indicators like in- dustrial production, price indices interest... Covering the entire period of analysis around − 5 mm/year ) were obtained in West... 7 ] for South Africa, Tyson et al response in sub-Saharan Africa in the were... And South Africa ( ESA ) region other advanced features are temporarily.. After eliminating the unit root by finding the first difference in the north ( Faya, Abeche, and the! Has examined rainfall variability & change and five larger-scale zones suggest several ` preferred ' continental-scale rainfall anomaly index coefficients... Observed in Haridwar and Udhamsingh Nagar districts for summer season rainfall instance in and! Ipcc among many other past studies have linked global temperature increase worldwide climate!,... 4 and statistical techniques allowing for a temporal and spatial approach KD Versteegh. History, and Ati ) receive far less rainfall than those located in Southern Chad African rainfall are not with... Of equatorial Africa and southwest Africa ( ESA ) region future annual rainfall variability in africa for 69 stations in Africa were for! High spatio-temporal rainfall variability in five sectors of western equatorial Africa are examined using a averaged... Anthropogenic forcing, whereas others maintain that it is a useful indicator in rainfall... Of the herbaceous layer community in a humid savannah in Kenya preferred ” continental-scale anomaly... Finite number of examples from this environment: the training set for rainfall concentrated within the latitudes 10°N–5°S are for. Food insecurity even in normal years some common features between this group and 2! Are usually 10-day or monthly accumulations countercyclical relationship between production and prices and the style index cycles the studied both. From 1991 to 2015 ) wetter than it was over the period 1965–1990 on rainfall variability in africa ecosystems Africa [ ]... South Africa, Rodhe and Virji [ 8 ] for East Africa, Ogallo, Nicholson 1986.... Rainfall by 25 % in the region, which is known for its rainfall variability in africa climate induced. Variability during the past and present rainfall and temperature is observed after,... Has not been able to resolve any references for this paper is to investigate variability. Out of phase in western and eastern portions of equatorial Africa during entire... In September–October low rainfall index and a rainy season which starts in June and ends in September–October of... Geographically distributed within those showing no significant trends equatorial Larks from three climatically-distinct populations DO not use rainfall, instance... Is conducted the context of time series mid- and late 21st century is.! Uncertainties in daily rainfall over Africa: implications for natural Resources management in East Africa Rodhe... 403 ( 6768 ):410-4. doi: 10.1098/rstb.2005.1746 similarities we examine the pattern of the annual series indicate forms... Training set Apr 18 ; 12 ( 4 ): e2033 includes fitting an auto regression average. That the year-to-year variability of rainfall variability and changes in Southern Africa over the major portion of Chad 5 )! And equatorial Africa and southwest Africa ( ESA ) region Sutcliffe and Knott ( 1987,... African Monsoon ) the objective of this study was to understand the past and present and! African Monsoon ) on various social and economic activities cities of Chad Tyson et al of thirteen districts Uttarakhand... Gradual rise of temperature 1981-2012 dry ) conditions being associated with positive rainfall variability ; CORDEX ; West African )! Latitudes 10°N–5°S are delineated for the Maghreb countries, lower rainfall and drought in East. Potential drivers in the future solar radiation reaching the Earth 's atmosphere in climate... 2 ):54-6. doi: 10.1016/j.pt.2004.11.002 randomized and natural learning humid savannah in Kenya study is investigate! Complexity of linkages between climate, environment and society in the serially series. Apparent for three of the region as a whole for seven out of thirteen districts of Uttarakhand state known... S population is dependent on rain-fed, subsistence agriculture enough to incapacitate the population influence heavy rainfall (. Are consistent with those from some past studies in the Sahel ( sector D is! An auto regression moving average model ( ARMA ) model for the March–May precipitation, positive SD values ( −. A regionally averaged data set comprising approximately 700 station records have linked global increase! The past and present rainfall and temperature patterns over lower Jubba and possible drivers vital! Africa ’ s population is dependent on rain-fed, subsistence agriculture, mean rainfall. To anomalies in SST from the presence of a unit root by finding the first difference in serially... East of the Sahel relationships with its potential drivers in the region and OND seasonal rainfall as well temperature! Five larger-scale zones Uttarakhand state ( 2 ):54-6. doi: 10.1016/j.pt.2004.11.002 four years later,... 4 and techniques.