Author(s)

Natiko Peter^1,2*, Wang Wen^1*, Nyasulu Matthews³, Raharivelo Sitraka Ny Aina¹, Alupot Donnata¹

¹School of Atmospheric Science, Nanjing University of Information Science & Technology, Nanjing, China.
²Uganda National Meteorological Authority, Directorate of Station Networks, Department of Instruments and Installations, Kampala, Uganda.
³School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, China.

Understanding the spatiotemporal variability of climatic parameters and their effects on pasture variability is vital for pasture management interventions over East Africa. The present study aims to assess the spatial-temporal variability of rainfall, temperature and Normalized Difference Vegetation Index (NDVI) (which is being used to assess pasture quality and productivity) over the region, between the period of 1982 and 2019. This study used annual mean values for rainfall, temperature and NDVI which were calculated for the period mentioned above. NDVI was derived from National Oceanic and Atmospheric Administration (NOAA) Global Area Cover (GAC) (NOAA-07-GAC) data. The rainfall data was acquired from the Climate Hazards Group Infrared Precipitation with Station (CHIRPS) while temperature is ERA5 reanalysis data sourced from the European Centre for Medium-Range Weather Forecasts (ECMWF). The study utilized the empirical orthogonal function (EOF) to identify patterns and dominant relationships between the climate variables. The correlation was calculated between rainfall, temperature and NDVI to assess the relationship among them. A non-parametric Mann-Kendall trends test was used to determine whether annual precipitation, temperature and NDVI had statistically increasing or decreasing trend. Results revealed a positive correlation between rainfall and NDVI while a negative correlation between NDVI and temperature. Positive correlation between rainfall and NDVI indicates that pasture health (quality and productivity), will improve accordingly. A negative correlation between temperature and NDVI indicates that pasture health will decrease with increase in temperature while improving with decreasing temperature. Outcome from this study suggests that changes in climatic variables influence the distribution of pasture in East Africa’s cattle grazing areas. The study hence recommends prioritisation of climatic (weather) information during pasture management over East Africa.

NDVI, Climatic Parameters, EOF, Pasture, East Africa

Peter, N. , Wen, W. , Matthews, N. , Aina, R. and Donnata, A. (2024) Spatio-Temporal Variability of Rainfall and Temperature and Their Effects on Pasture Variability over East Africa: Implication on the Cattle Grazing Areas. Journal of Geoscience and Environment Protection, 12, 54-69. doi: 10.4236/gep.2024.123004.