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The greater horn of Africa is one of the least developed regions in Africa. Livestock are an important economic resource and an essential asset for poor farmers in this region. Climate variability, population growth, low economic ...
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The greater horn of Africa is one of the least developed regions in Africa. Livestock are an important economic resource and an essential asset for poor farmers in this region. Climate variability, population growth, low economic development, limited market integration, and low fertilizer use, amongst others put serious pressure on livestock production. The sustainability of the livestock production in the rangelands and the integrated crop-livestock systems is further jeopardised by climate change. The uncertainties associated with climate change impacts call for interventions that empower communities to effectively cope with current climatic variability and to adapt to unexpected future consequences. Risk management and climate-robust development both appear to be promising approaches. Index-based livestock insurance, for example, offers innovative opportunities for protecting farmers' assets, while diversification in the arid- and semi-arid regions might turn into economically viable livelihood strategies. These adaptation options will only be adopted if the right systems of incentives and policies are put in place.
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Israel hosts documented labor migrants (DLM), and recently also undocumented migrants (UDM), mostly from Horn of Africa. This study aims to compare treatment outcomes and other clinical aspects between a sample of 154 DLM and 113 ...
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Israel hosts documented labor migrants (DLM), and recently also undocumented migrants (UDM), mostly from Horn of Africa. This study aims to compare treatment outcomes and other clinical aspects between a sample of 154 DLM and 113 UDM who were treated in two tuberculosis clinics between 2005 and 2010.
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This article examines recent rainfall conditions in two sectors of eastern Africa, the summer rainfall region and the equatorial rainfall region with rainy seasons in the boreal spring and boreal autumn. The analysis covers the ye...
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This article examines recent rainfall conditions in two sectors of eastern Africa, the summer rainfall region and the equatorial rainfall region with rainy seasons in the boreal spring and boreal autumn. The analysis covers the years 1998-2014 and is carried out using TRMM 3B43 Version 7 rainfall estimates. In both regions, extensive periods of anomalously low rainfall and prolonged drought have prevailed since roughly 2008. Prior to that time, only three periods of drought are noteworthy 1998/1999, 2000, and 2005. The post-2008 drought conditions were interrupted by floods in both regions in February 2010 and in several years in the equatorial region. This rapid alternation between extremes creates additional hardships on the population. Two notable results emerge from this analysis. One is the tendency for similar trends in interannual variability in both regions, despite vastly different rainfall regimes. The other is the persistence of recent droughts through several rainy seasons. The implication of these results is that one or more factors in interannual variability is operative in all seasons. This could account for the common trends in the equatorial and summer rainfall regions.
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Background: The association between the prevalence of hepatitis C virus (HCV) and immigration is rarely studied, particularly for the immigrants crossing to the resettlement countries. Most of the published data are confined to th...
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Background: The association between the prevalence of hepatitis C virus (HCV) and immigration is rarely studied, particularly for the immigrants crossing to the resettlement countries. Most of the published data are confined to those immigrants who were resident in European countries and rarely immigrated before they reach the final destination. Libya is a large country in North Africa with the longest coast of the Mediterranean Sea facing the European Union. It has been considered as the main transient station for African immigrants to Europe. The objectives of this study were to determine: (1) the prevalence of HCV in African immigrants gathered in Libya from different African countries on their way to Europe and (2) HCV genotype distribution in these immigrants and its correlation with different demographic factors.
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The main rainy season in Ethiopia occurs during the northern hemisphere summer, when air masses carrying moisture from the Indian Ocean, the Gulf of Guinea, the African continent, the Red Sea, and the Mediterranean Sea converge ab...
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The main rainy season in Ethiopia occurs during the northern hemisphere summer, when air masses carrying moisture from the Indian Ocean, the Gulf of Guinea, the African continent, the Red Sea, and the Mediterranean Sea converge above the Ethiopian mountain plateau. In this study, the variability in different branches of this transport has been studied using the Lagrangian trajectory model FLEXPART and ERA-Interim reanalysis data of July-August 1998-2008. The largest relative fluctuations occur in the normally limited transport from the Gulf of Guinea, whereas smaller relative changes in the larger branches from the Indian Ocean and the regions to the north often have greater effects. Wet/dry summer months in the northern Ethiopian highlands were associated with increased/reduced transport of moisture from the south, with consequent changes in the release of moisture in the region. In dry months, the moisture transport from the south was reduced to 85% of its mean, and in wet months, it was increased to 107%. The increased transport in wet months could be attributed to low-level westerly anomalies above Central Africa - increasing moisture transport from the Gulf of Guinea and in most cases also from the Indian Ocean - and with enhanced southerlies along the coast of East Africa, increasing the transport from the Indian Ocean. The amount of moisture transported into the highlands from the north could not be consistently associated with wet and dry months, but in most cases, the release of moisture in air coming from the north contributed to the resulting precipitation anomaly. The release of moisture in the northern branch was reduced to 94% of its mean in dry months and increased to 111% in wet months. This may be an effect of altered convergence associated with changes in the transport from the south.
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In the northern highlands of Ethiopia, gully erosion is severe. Despite many efforts to implement gully prevention measures, controlling gully erosion remains a challenge. The objective is to better understand the regional gully e...
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In the northern highlands of Ethiopia, gully erosion is severe. Despite many efforts to implement gully prevention measures, controlling gully erosion remains a challenge. The objective is to better understand the regional gully erosion processes and to prevent gully head retreat. The study was conducted in the Ene-Chilala catchment in the sub-humid headwaters of the Birr River located southwest of Bahir Dar, Ethiopia. Twelve gully heads were monitored during the 2014 and 2015 rainy monsoon phase. We measured gully head morphology and retreat length, soil shear strength, ground water table levels, and catchment physical characteristics. Two active gully head cuts were treated in 2014 and an additional three head cuts in 2015 by regrading their slope to 45 degrees and covering them with stone riprap. These treatments halted the gully head advance. The untreated gullies were actively eroding due to groundwater at shallow depths. The largest head retreat was 22.5 m, of which about half occurred in August of the first year when the surrounding soil was fully saturated. Lowering both the water table and protecting the gully heads can play a key role in reducing gully expansion and soil loss due to gully erosion in the Ethiopian highlands. Copyright (C) 2016 John Wiley & Sons, Ltd.
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Abstract The Horn of Africa drylands (HAD) are among the most vulnerable regions to hydroclimatic extremes. The two rainfall seasons—long and short rains—exhibit high intraseasonal and interannual variability. Accurately simulat...
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Abstract The Horn of Africa drylands (HAD) are among the most vulnerable regions to hydroclimatic extremes. The two rainfall seasons—long and short rains—exhibit high intraseasonal and interannual variability. Accurately simulating the long and short rains has proven to be a significant challenge for the current generation of weather and climate models, revealing key gaps in our understanding of the drivers of rainfall in the region. In contrast to existing climate modeling and observation‐based studies, here we analyze the HAD rainfall from an observationally‐constrained Lagrangian perspective. We quantify and map the region's major oceanic and terrestrial sources of moisture. Specifically, our results show that the Arabian Sea (through its influence on the northeast monsoon circulation) and the southern Indian Ocean (via the Somali low‐level jet) contribute ～80% of the HAD rainfall. We see that moisture contributions from land sources are very low at the beginning of each season, but supply up to ～20% from the second month onwards, that is, when the oceanic‐origin rainfall has already increased water availability over land. Further, our findings suggest that the interannual variability in the long and short rains is driven by changes in circulation patterns and regional thermodynamic processes rather than changes in ocean evaporation. Our results can be used to better evaluate, and potentially improve, numerical weather prediction and climate models, and have important implications for (sub‐)seasonal forecasts and long‐term projections of the HAD rainfall.
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The Ethiopian summer rains occur as air masses of various origins converge above the Ethiopian plateau. In this study, the relative importance of different moisture transport branches has been estimated using the Lagrangian trajec...
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The Ethiopian summer rains occur as air masses of various origins converge above the Ethiopian plateau. In this study, the relative importance of different moisture transport branches has been estimated using the Lagrangian trajectory model FLEXPART, and ERA-Interim reanalysis data, to backtrack air reaching the northern Ethiopian highlands in July-August 1998-2008. The Indian Ocean, the Congo Basin and the Red Sea were found to be important moisture source regions; for air from the Indian Ocean aided by a considerable moisture uptake along routes across the African continent. The following main transport branches were identified: (1) Flow from the Gulf of Guinea, (2) Flow from the Indian Ocean, and (3) Flow from the north; from the Mediterranean region across the Red Sea and the Arabian Peninsula. The largest contribution to the moisture transport into, and release of moisture within, the northern Ethiopian highlands, was associated with air traveling from the Indian Ocean and from the north. This was partly due to the relatively high mean specific humidity of this air, and partly because a large proportion of the air that reaches the highlands, follows these routes. As a total, the amount of moisture brought into the highlands from the north is 46% higher than from the south, whereas the contribution to moisture release within the highlands is about equal for air coming from the south and from the north. While previous studies have emphasized the importance of the Gulf of Guinea, we find that despite the high specific humidity of the low-level flow of air from the Gulf of Guinea, the amount of moisture carried into and released within the northern Ethiopian highlands through this branch, is much smaller than from the other branches-about 1/8 of that from the Indian Ocean. This is due to the fact that normally only a small proportion of the air reaching Ethiopia comes from the Gulf of Guinea.
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The variation of normalized difference vegetation index (NDVI) mainly depends on the change of climatic factors (precipitation and temperature). This study is assessing and analyzing the inter-annual and seasonal change of NDVI in...
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The variation of normalized difference vegetation index (NDVI) mainly depends on the change of climatic factors (precipitation and temperature). This study is assessing and analyzing the inter-annual and seasonal change of NDVI in the Horn of Africa (HOA) (1982–2013). The relationship between climatic factors and NDVI values of global Inventory monitoring Modeling System (GIMMS) from 1982 to 2013 was analyzed by means of ordinary least squares, vegetation slope, simple linear regression and correlation coefficients. In addition, the land cover data of the (MODIS) Medium Resolution Imaging Spectroradiometer (i.e. MCD12Q1) are used to assess land-use change from 2001 to 2013 and GIMMS land cover data also applied to extract annual NDVI maximum from 1982 to 2013. The results show that NDVI is proportional to precipitation and inversely proportional to temperature, which precipitation decreased insignificantly while temperature increased significantly for the last 3 decades. In general, NDVI values gradually rise from spring to rainy season and fall steadily from autumn to winter. The NDVI of grassland, savanna and shrub land is more sensitive to climate change than the NDVI of forest and woodland. In grassland, savanna and shrub, NDVI gradients are positive, while in desert areas negative changes are recorded, while forests and woodlands are in transition between stable and positive NDVI gradients. The average NDVI value of each vegetation cover gradually increased from 1982 to 1998 and then slowly decreased from 1998 to 2013 due to precipitation variation. Forest and woodland cover were declined by approximately 0.4% and 1.28% in the past 2 decades. Thus, in the Horn of Africa, land degradation, such as deforestation and desertification, is a serious environmental problem.
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A small collection of bats composed of six species from Dire Dawa area, eastern Ethiopia, is presented. Besides three species previously known in the region, Rousettus aegyptiacus, Epomophorus minimus and Chaerephon pumilus, three...
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A small collection of bats composed of six species from Dire Dawa area, eastern Ethiopia, is presented. Besides three species previously known in the region, Rousettus aegyptiacus, Epomophorus minimus and Chaerephon pumilus, three bats were newly documented from the area, Rhinopoma microphyllum, R. cystops and Scotophilus leucogaster. R. microphyllum is here reported for the first time in Ethiopia. From molecular genetic comparisons Ethiopian R. cystops belongs to the Arabian subspecies lineage R. c. arabium, previously unknown from the African continent, raising interesting biogeographic questions.
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