A numerical experiment where the values of T dew are altered to compensate for the RH error suggests that eliminating the atmospheric moisture bias could, in and of itself, decrease runoff up to 14 % in high-altitude regions east of the Sierra Nevada and Cascades, and reduce estimated Colorado River runoff at Lees Ferry up to 4 % by the end of the century. The annual minimum temperature had a significantly increasing trend with the value varying from 0.005 C/year and 1.90% in GIN station to 0.12 C/year and 52.40% in the DBS station. The Geologic Processes: Endogenic and Exogenic Forces, 2.3. Geological Processes and the Resulting Landforms of Ethiopia and the Horn, 2.5. However, the magnitude of the significantly decreasing trend was observed at SD station (0.90 mm/year and 16.20% change) and the significantly decreasing trend of belg season rainfall varied between 0.12 mm/year and 10.00% at GIN station to a significantly increasing trend of 0.40 mm/year and 30.00% at DB station. High correlation existed between crops and rainfall, and temperature was found to have a direct impact on the communities, particularly rain-fed dependants. Controlled grazing: Intensive, permanent and continuous grazing facilitate erosion and loss of fertile soil, resulting in low productivity and further shortages of grazing land. The minimum temperatures increased at a higher rate than the maximum temperatures during winter, summer, autumn and also at the annual timescale. Therefore, the consecutive occurrence of frequent tropical depression over the South West Indian Ocean (SWIO) overlapped with the recurrent drought of Ethiopia (1972 and 1984). Rainfall and temperature trends detection is vital for water resources management and decision support systems in agro-hydrology. Water harvesting and integrated water resources management: In order to reduce the vulnerabilities of rural communities that arise from spatiotemporal water shortages and rainfall variability, rainwater harvesting has significant benefits. Therefore, information related to various climatic parameters of the area to the local level is of paramount importance in order to plan for other development issues. The spatial distribution pattern of annual and seasonal rainfall for the Beressa watershed is shown in Figure4. Such studies ignored the localized trends of rainfall and temperature, particularly in most highlands of Ethiopia. During the belg (small rainy) season the subdivision indicates a slightly increasing rainfall trend and the bega season (dry season) shows a negative trend, as already presented in Figure2. 3.1 Spatial distribution of rainfall in Ethiopia. Hydro-meteorological instrumentation: For monitoring of quality data, which would be an early warning system, forecasting/projection and disaster response with timely information. Rock and Mineral Resources of Ethiopia, CHAPTER THREE THE TOPOGRAPHY OF ETHIOPIA AND THE HORN, 3.2. seasonal, mean annual rainfall including the mean, minimum and maximum temperature spatiotemporal trend as well as its impacts on crop production at the Beressa watershed from 19802014 (35 years). Likewise, the increase of surface temperature will adversely affect the availability of water resources, distribution, intensity and magnitude of rainfall in the long term (Barnett et al. Simulations using the Variable Infiltration Capacity (VIC) hydrology model indicate that a drier and warmer future will shift the location of snow line to higher elevations and reduce the number of days with precipitation falling as snow. Elements and Controls of Weather and Climate, 5.3. The Mann-Kendall test results showed that the annual and seasonal rainfall trend was highly variable. 2012; Fazzini et al. Notably, there is a significant increase in the maximum number of consecutive dry days and significant decreases in the number of days with at least 1 and 10 mm of precipitation. s u m m a r y Due to global warming the climate of central Chile is expected to experience dramatic changes in the 21st century including declining precipitation, earlier streamflow peaks, and a greater proportion of precipitation falling as rain. In the years to come the adverse effect of global warming will increase unless solution oriented problem solving mechanisms are put into practice (Kumar et al. The northeasterly winds crossing the Red Seacarry very little moisture and supplies rain only to the Afar lowlands and the Red Sea coastalareas.iv. Therefore, in order to know the yields, annual rainfall is less important for prediction. 3. The results of bega rainfall trends revealed a significantly decreasing trend in four out of seven stations. The percentage change over a period of time can be obtained from Sen's median slope and mean by assuming the linear trend in the long-term series using the following formula: In statistical terms, the moving average is also known as running average, used in order to explore a set of various data by creating an average value of various subsets for a data set. 2010; Simane et al. A positive trend for kiremit season rainfall showed in all stations and the trend of rainfall during belg season revealed a positive trend in six out of seven stations. The magnitude of the decreasing trend was found to be 0.06 mm/year and 7.50% in GIN station, 0.05 mm/year and 8.80% at SD station, 0.11 mm/year and 12.70% at HG station, 0.13 mm/year and 29.00% change at SH station, 0.19 mm/year and 53.00% at DB station, 0.19 mm/year and 35.00% and 0.20 mm/year and 56.40% change at DBS station. This study involves the observation of climatic variables, i.e. The spatiotemporal rainfall and temperature distribution are presented in Figures4 and 5 respectively. The average rainfall inthe region varies from 1,400 to over 2,200 mm/year.iii. Out of seven stations, long-term annual maximum temperature has shown a significantly increasing trend (three stations at 5% significance level and two stations at 10% significance level). For instance, unlikeother parts of Ethiopia, the southern and southwestern highlands experience reducedtemperature. For instance belg (spring) rain is more constrained by cyclonic activity than kiremit (summer season) rain. Enter the email address you signed up with and we'll email you a reset link. Observed Data Therefore, if the income from one source decreases, they still have other income sources which will provide economic relief and the capability to cope with and adapt to climatic variability (Kelly & Adger 2000). The average annual aerial rainfall of the Beressa watershed is 891 mm, with a coefficient variation of 30.6% and standard deviation of 227 mm. To achieve this objective, long-term historical monthly rainfall and temperature data were recorded and analyzed for more than 100 years (1900-2016). Autumn (September, October and November)Autumnis the season of the year between summer and winter. The percentage changes of mean annual temperature were found to be at maximum change for SD station (31.30%) and at minimum change for DB station (7.60%). For example, months from March to June in Ethiopiahave records of highest temperatures. We used 12-member ensembles of General Circulation Models (GCMs) from the Coupled Model Intercomparison Project Phase 3 (CMIP3) and Phase 5 (CMIP5) to evaluate climate-attributed changes in the hydrology of the Mataquito river basin in central Chile, South America. Spatiotemporal variability and trends of rainfall and temperature in the Northeastern Highlands of Ethiopia Authors: Abebe Arega Mekonen Arega Bazezew Berlie Bahir Dar University Abstract. The calculated PCI for seasonal as well as inter-annual rainfall distribution for the spatiotemporal time series is shown in Table2. For the kiremit (summer season), the main rainfall source is the northward oscillation of ITCZ and the development of high-pressure systems along the southern Atlantic as well as South Indian Oceans. To encompass the system, it needsan understanding of the position of Inter Tropical Convergence Zone (ITC), pressure cells, andTrade Winds. The production of beans was below 18-year mean in nine years out of 18 years production periods, as indicated in Table5, which accounts for 50% of the total bean production; while in respect of kiremit rainfall pea, chickpea, and lentil production (50, 50 and 55.5% respectively) were below the 18-year mean. You can download the paper by clicking the button above. The mean annual rainfall of the basin spatially varies from 417 to 1012 mm, with a noticeable temporal variation at a monthly time scale. The spatial distribution of temperature in Ethiopia is primarily determined by altitude andlatitude. Soil moisture is one of the essential climate variables with a potential impact on local climate variability. Let X1, X2, X3. As a result, they cover different past and future time periods, and information is presented at different levels of regional aggregation. During this time, thecentral highlands, southeastern highlands and lowlands receives rainfall as the south easterliesbring moist winds. Adaptation strategies are not limited to the current weather conditions (single season rainfall and temperature), rather they extend to the need for communities to adapt to prolonged climatic variability over time (Cooper et al. The study watershed lies between 39 37E39 32E and 9 40N9 41N. The future climate also shows a continuing positive trend in the temperature extreme indices as well as more frequent extreme rainfall events. The results of correlation analysis between crop production and climatic variables (rainfall and temperature) during the period 19972014 are shown in Table5. In Ethiopia and elsewhere in the Horn,temperature shows seasonal variations. Even though the slope of Sen's estimator for kiremit season, annual rainfall, and belg season rainfall indicate a positive trend, it does not reflect sufficient availability of rainfall, as the rainfall distribution was erratic, irregular and variable in distribution (as already indicated in Figure 2 and Table2). Water Resources: Rivers, Lakes and Sub-Surface Water, 4.4. 2015; Wagesho & Yohannes 2016). Here, the frequency and intensity of extreme precipitation over Zambia are analysed for the period 20212100 using an ensemble of 5 CMIP5 models from those recommended by the Intergovernmental Panel on Climate Change (IPCC). During this season, Northeasterly windsoriginating from the landmass of Asia dominantly prevail Ethiopian landmass. The capital of Ethiopia, Addis Ababa, is located at an elevation of 7,726 feet, and as such its climate remains relatively cool throughout the year. On the other hand, 19 years (54.3%) recorded more than the annual average rainfall. Tmean, the mean annual temperature; Tmin, minimum annual temperature; Tmax, maximum annual temperature. Do we have dynamics in temperature and rainfall in Ethiopia? However, in the belg season during the period 19802014 the five years' average moving annual and seasonal rainfall was considerably variable. In kiremit season, rain is essential but it extends to the bega season during the harvesting stage. Some other studies used seasonal or annual rainfall and temperature trend and variability analysis (Conway & Schipper 2011). Although the correlation coefficients of crop production and climatic variables are positive, in terms of statistical significance most of them show insignificant correlationexcept barley and wheat, which are significantly correlated with belg, kiremit season and during the month of May. In administrative terms, it is located in Basona Worena District, in the North Showa zone of Amhara regional state (Figure1), situated 180 km northeast of the capital city, Addis Ababa. For instance, during the years 19811984, the trend of annual rainfall was lower than the mean long-term rainfall, although slight recovery was shown between 1985 and 1986. Therefore, it can be concluded that during the last 35 years there have been continuous changes and variations of climatic variables in the watershed. The results revealed that the magnitude of significantly increasing trend and variability was observed in mean annual rainfall for DB station (at 0.28 mm/year and 1.07%). In autumn the ITCZ shiftstowards the equator weakening the equatorial westerlies. The Physiographic Divisions of Ethiopia, 3.3. The line connecting the fixed average is known as averagely moving. Details of the test statistics are discussed in the subsequent sections. Moving average rainfall and temperature can be obtained by using the following equation: Inverse distance weighted interpolation methods (IDW) have been used in order to analyse annual and seasonal rainfall and temperature. However, local farmers evaluate climatic variability in relation to their crop productivity. Barley, wheat, horse beans, field peas, lentils and chickpeas are commonly grown crops. rainfall, temperature and evaporation) which would have a considerable impact on crop productivity, water resources and the overall assets of the community (Worku et al. At the annual scale, maximum and minimum temperatures significantly increased in over 33% of the Basin at a rate of 0.1 and 0.15 C per decade, respectively; however, the western part (12%) of. The Sen's slope estimator was employed after Mann-Kendal test statistics in order to determine the change and variability of rainfall and temperature trends through time series. A significantly declining trend of bega season rainfall was observed in all stations with the trend magnitude of 0.61 mm/year and 7.50% in GIN station to 0.21 mm/year and 56.40% in DBS station. Water harvesting is particularly important for less rainy seasons and integrated water management, and will provide supplementary irrigation during deficits. The present results are in agreement with Parry (2007), who stated that due to a prolonged increase in the emission of gases through human activities and expansion of industry, the surface temperature has increased by about 1 C. Spatiotemporal Patterns and Distribution of Temperature and Rainfall in Ethiopia, 5.5. The researches and analysis in this study indicates that, while climate change is likely to pose serious threats to development in the RM, it also has the potential to bring opportunities. All these coping and adaptation mechanisms are important at the local level in order to increase the resilience of communities and ecosystems to the variability and irregularity of climatic shocks (Abramovitz et al. Result, they cover different past and future time periods, and will provide supplementary during. Example, months from March to June in Ethiopiahave records of highest temperatures ) the! 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discuss spatiotemporal distribution of temperature and rainfall in ethiopia