Changes and variability of precipitation and temperature in the Guna Tana watershed, Upper Blue Nile Basin, Ethiopia
- 12 Downloads
This paper studied the spatial and temporal variability of the statistical structures of precipitation Guna Tana watershed, Upper Blue Nile, Ethiopia, by analyzing the time series of temperature and precipitation from six weather stations during the period from 1990 to 2016. Inverse distance weight, precipitation concentration index and MK test statics were used to detect annual and seasonal precipitation concentrations and the associated spatial patterns. The results show that precipitation concentration index values were mainly observed in Guna Tana watershed in which about 83.33% and 16.67% were the uniform concentration of precipitation and strong irregularity of precipitation distribution was observed in the kiremt seasons’ rainfall. The demonstration using Mann–Kendall trend test depicted that most parts of Guna Tana watershed are characterized by variability of precipitation and temperature. The results reveal that significant trends in average rainfall were observed (both positive and negative trends). Those significantly decreasing trends of average monsoon rainfall have the highest value of decreasing slope (i.e., − 1.88 mm/year) for Luwaye station and percentage change of − 31.07% in Bega season. Decreasing slopes (− 0.14 °C/year) and percentage change (− 22.79%) were observed in Luwaye station at the average annual minimum temperature and increasing Sen’s slope temperature recorded at 24.64 °C/year and percentage changes at 0.136% in 10% level of significance at Woreta station in average annual minimum temperature.
KeywordsVariability Guna watershed Precipitation Concentration Index
I am grateful for Schlumberger Foundation, Faculty for the Future for providing me a financial support. Special thanks go to the community live in the study area, for their kind support for field work and data availability. They deserve my sincere thanks and appreciation.
- Ayalew D, Tesfaye K, Mamo G, Yitaferu B, Bayu W (2012) Variability of rainfall and its current trend in Amhara region, Ethiopia. Afr J Agric Res 7(10):1475–1486Google Scholar
- Gowda KK, Majuantha K, Manjunath BM, Putty YR (2008) Study of climate changes at Davangere region by using climatological data. Water Energy Int 65(3):66–77Google Scholar
- Hirsch RM, Helsel DR, Cohn TA, Gilroy EJ, Maidment DR (1992) Statistical analysis of hydrologic data. Handbook of hydrology. McGraw-Hill Education, New York, pp 1–17Google Scholar
- Kenabatho P, Parida B, Moalafhi D (2012) The value of largescale climate variables in climate change assessment: the case of Botswana’s rainfall. Phys Chem Earth Parts A/B/C 50(64):71Google Scholar
- Kendall MG (1975) Rank correlation methods. Griffin, LondonGoogle Scholar