what is rainfall variability

For instance, rainfalls in Victoria during the period 1913-76 tended to be about 10 per cent less than average each 2.1 years or so. A study by Tilahun [11] based on the cumulative departure index established that parts of Northern and Central Ethiopia persistently received below average rainfall for the rains received between February and August since 1970. The stepwise methodology is summarized in Figure 2. Noticeably, Embu appeared to be receiving more near average rainfall during SRs (2002, 2003, 2007, and 2011) contrary to the trends observed in Mbeere region (especially in Kindaruma and Kiambere) (Figure 4). The resulting numerical value can be used to characterize the climate of a region in various ways. The degree to which rainfall amounts vary across an area or through time is an important characteristic of the climate of an area. variability of precipitation may be measured in various ways. saptial variability and temporal variability. Eludoyin et al. Rainfall variability in the broader tropical SPCZ region is well represented by rainfall variability at the Solomon Is-lands. [21] who reported high coefficient of variation for seasonal (315%) and annual (50–114%) rainfall in semiarid Ecotope, northeast of South Africa. Thus, deficit is likely to prevail throughout the rain seasons as observed in other SSA regions (Li et al., 2006). Nicholson (1993) and Hulme [26] attributed the decrease in LRs to the desiccation (drying out) of the March-to-August rains in sub-Saharan Africa (SSA). saptial variability and temporal variability. High probabilities of dry-spells were in March (0.72 and 0.55) and December (0.8 and 0.6) in average subhumid (Machang’a, Kiritiri, Kiambere, and Kindaruma) stations and humid ones (Embu), respectively (Figure 5). Ignoring this effect, would you think that areal variability of precipitation is high or low in, say, our portion of California and why? Frequency analyses of meteorological data require that the time series be homogenous in order to gain in-depth and representative understanding of the trends over time [17]. Box 6-60100, Embu, Kenya, TSBF-CIAT, Tropical Soil Biology and Fertility Institute of CIAT, P.O. The efficacy of interpolation techniques was assessed using mean absolute errors (MAE) (9) and root mean square errors (RMSE) (10) statistics plus validation using gauged rainfall data:where and are the predicted and observed or measured rainfall values. Since rainfall which is heterogeneous, in particular, is the most critical factor determining rain-fed agriculture, knowledge of its statistical properties derived from long-term observation could be utilized in developing optimal mitigation strategies in the area. This thesis investigates the conditions under which rainfall variability affects violent, state-based conflict. Some of the variability does not appear to be caused systematically and occurs at random times. The rainfall data were from five rainfall stations: Machang’a, Kiritiri, Kiambere, and Kindaruma (herein commonly referred to as Mbeere region) and Embu (Embu). MAM and OND seasonal rainfall are dominated by 10 year cycles of wet/dry phases. The IPCC climate models predict, for the Maghreb countries, lower rainfall and increased aridity. Box 43844-00100, Nairobi, Kenya, 3Embu University College, P.O. Before frequency analysis of the rainfall data is done, various transformations are essential for the data to follow particular probability distribution patters. While studying vegetation dynamics based on the normalized difference vegetation index (NDVI), Tucker and Anyamba (2005) noted persistent droughts and unpredictable rainfall patterns marked by reduction in the NVDI values during LRs for periods approaching the 21st century. The link is context specific towards Mbeere stations planting crops on the climate-conflict nexus has produced diverse results which... 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A larger range for the plant growth during the growing season trigger reduced harvests or complete! A time interval events are occasioned by the WMO under IDW method was what is rainfall variability to illustrate français-anglais et moteur recherche.

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