Analysis of Temporal Variability and Trends of Rainfall and Temperature Over Western Amhara Region, Ethiopia

Tilahun Sewagegn¹

1. Ethiopian Meteorology Institute (EMI) Western Amhara Meteorological Service Center, P. O. Box 219, Bahir Dar, Ethiopia.

Section:Research Paper, Product Type: Journal-Paper
Vol.10 , Issue.7 , pp.96-106, Jul-2024

Online published on Jul 31, 2024

Copyright © Tilahun Sewagegn . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
 

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Abstract :
This study examined the temporal trends and variability of rainfall and temperature in seasonal and annual time series over western Amhara, Ethiopia. The 75 weather stations of daily precipitation and the 49 stations of daily maximum and minimum temperature were collected from the Western Amhara Meteorological Service Center from 1989 to 2018. Then, after quality checking, the daily data was arranged in a Microsoft Excel spreadsheet and analyzed using statistical analysis software (XLSTAT), Arc GIS 10.3 software, and the R program. The results indicated that western Amhara receives its rainfall mostly in Bega, Belg, and Kiremt and annually receives 100–300 mm, 120–350 mm, 800-1600 mm, and 1100-2000 mm, respectively. The statistics reveal that the maximum and minimum temperatures of the region increased annually by 0.0905°C and 0.0886°C, respectively. Similarly, the rainfall trend slightly increases in the Belg season, Kiremt season, and annually, but not during the Bega season. The rainfall variability was high, with a coefficient of variation (CV = 48.42% and CV = 37.2%) in the Bega and Belg seasons, respectively. However, the rainfall variability was moderate on Kiremt and annually (CV = 29.02% and CV = 27.79%). The results further indicated that the Awi zone has the best rainfall distribution, mostly more than 1600 mm. Some parts of this zone, like Enjibara and Tilili, receive more than 2200 mm of rainfall annually. West Gondar zone received the lowest rainfall amount in the region.

Key-Words / Index Term :
rainfall, temperature, temporal variation, Mann-Kendall test, western Amhara

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