Climate change has intensified temperature extremes worldwide, with particularly severe implications for semi-arid regions such as southern Ethiopia. This study assessed historical and future temperature extremes across the Borana Zone using ENACTS observational datasets (1985–2014) and bias-corrected outputs from nine CMIP6 global climate models under SSP2-4.5 and SSP5-8.5 scenarios. Extreme temperature indices recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI) were computed using the Climate Data Tool. Model performance was evaluated using correlation coefficient, mean error, mean absolute error, root mean square error, and index of agreement. Long-term trends were assessed using the Mann–Kendall test and Sen's slope estimator, while Pearson correlation analysis was employed to investigate relationships between temperature extremes and major large-scale climate indices, including ENSO, PDO, IOD, SOI, and AMO. Results indicate statistically significant increases in warm temperature indices (TN90p, TX90p, TNx, TXx) and significant decreases in cold extremes (TN10p and CSDI), indicating an overall warming climate with stronger nighttime warming. Future projections show substantial increases in mean temperature and warm spell duration under both emission scenarios, with the highest warming projected under SSP5-8.5 by the late twenty-first century. Diurnal temperature range is projected to decrease, reflecting accelerated increases in minimum temperature relative to maximum temperature. Significant relationships between several temperature extremes and large-scale climate indices demonstrate the influence of global climate variability on regional temperature behavior. These findings provide important scientific evidence for climate adaptation planning, drought preparedness, and sustainable management of pastoral systems in the Borana Zone.
| Published in | Science Discovery Environment (Volume 1, Issue 4) |
| DOI | 10.11648/j.sdenv.20260104.14 |
| Page(s) | 215-233 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2026. Published by Science Publishing Group |
Borana Zone, CMIP6, Mann Kendall, Large Scale Climate Indices, Sen.’s Slope, Temperature Extremes
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APA Style
Arrefaine, M. G., Weldegerima, T. M. (2026). Spatiotemporal Analysis of Temperature Extremes Under Future Climate Scenarios in the Borana Zone, Ethiopia. Science Discovery Environment, 1(4), 215-233. https://doi.org/10.11648/j.sdenv.20260104.14
ACS Style
Arrefaine, M. G.; Weldegerima, T. M. Spatiotemporal Analysis of Temperature Extremes Under Future Climate Scenarios in the Borana Zone, Ethiopia. Sci. Discov. Environ. 2026, 1(4), 215-233. doi: 10.11648/j.sdenv.20260104.14
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Download@article{10.11648/j.sdenv.20260104.14,
author = {Mikiyas Gebre Arrefaine and Tesfay Mekonnen Weldegerima},
title = {Spatiotemporal Analysis of Temperature Extremes Under Future Climate Scenarios in the Borana Zone, Ethiopia},
journal = {Science Discovery Environment},
volume = {1},
number = {4},
pages = {215-233},
doi = {10.11648/j.sdenv.20260104.14},
url = {https://doi.org/10.11648/j.sdenv.20260104.14},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.sdenv.20260104.14},
abstract = {Climate change has intensified temperature extremes worldwide, with particularly severe implications for semi-arid regions such as southern Ethiopia. This study assessed historical and future temperature extremes across the Borana Zone using ENACTS observational datasets (1985–2014) and bias-corrected outputs from nine CMIP6 global climate models under SSP2-4.5 and SSP5-8.5 scenarios. Extreme temperature indices recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI) were computed using the Climate Data Tool. Model performance was evaluated using correlation coefficient, mean error, mean absolute error, root mean square error, and index of agreement. Long-term trends were assessed using the Mann–Kendall test and Sen's slope estimator, while Pearson correlation analysis was employed to investigate relationships between temperature extremes and major large-scale climate indices, including ENSO, PDO, IOD, SOI, and AMO. Results indicate statistically significant increases in warm temperature indices (TN90p, TX90p, TNx, TXx) and significant decreases in cold extremes (TN10p and CSDI), indicating an overall warming climate with stronger nighttime warming. Future projections show substantial increases in mean temperature and warm spell duration under both emission scenarios, with the highest warming projected under SSP5-8.5 by the late twenty-first century. Diurnal temperature range is projected to decrease, reflecting accelerated increases in minimum temperature relative to maximum temperature. Significant relationships between several temperature extremes and large-scale climate indices demonstrate the influence of global climate variability on regional temperature behavior. These findings provide important scientific evidence for climate adaptation planning, drought preparedness, and sustainable management of pastoral systems in the Borana Zone.},
year = {2026}
}
TY - JOUR T1 - Spatiotemporal Analysis of Temperature Extremes Under Future Climate Scenarios in the Borana Zone, Ethiopia AU - Mikiyas Gebre Arrefaine AU - Tesfay Mekonnen Weldegerima Y1 - 2026/11/06 PY - 2026 N1 - https://doi.org/10.11648/j.sdenv.20260104.14 DO - 10.11648/j.sdenv.20260104.14 T2 - Science Discovery Environment JF - Science Discovery Environment JO - Science Discovery Environment SP - 215 EP - 233 PB - Science Publishing Group SN - 3071-5431 UR - https://doi.org/10.11648/j.sdenv.20260104.14 AB - Climate change has intensified temperature extremes worldwide, with particularly severe implications for semi-arid regions such as southern Ethiopia. This study assessed historical and future temperature extremes across the Borana Zone using ENACTS observational datasets (1985–2014) and bias-corrected outputs from nine CMIP6 global climate models under SSP2-4.5 and SSP5-8.5 scenarios. Extreme temperature indices recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI) were computed using the Climate Data Tool. Model performance was evaluated using correlation coefficient, mean error, mean absolute error, root mean square error, and index of agreement. Long-term trends were assessed using the Mann–Kendall test and Sen's slope estimator, while Pearson correlation analysis was employed to investigate relationships between temperature extremes and major large-scale climate indices, including ENSO, PDO, IOD, SOI, and AMO. Results indicate statistically significant increases in warm temperature indices (TN90p, TX90p, TNx, TXx) and significant decreases in cold extremes (TN10p and CSDI), indicating an overall warming climate with stronger nighttime warming. Future projections show substantial increases in mean temperature and warm spell duration under both emission scenarios, with the highest warming projected under SSP5-8.5 by the late twenty-first century. Diurnal temperature range is projected to decrease, reflecting accelerated increases in minimum temperature relative to maximum temperature. Significant relationships between several temperature extremes and large-scale climate indices demonstrate the influence of global climate variability on regional temperature behavior. These findings provide important scientific evidence for climate adaptation planning, drought preparedness, and sustainable management of pastoral systems in the Borana Zone. VL - 1 IS - 4 ER -
Ethiopian Meteorology Institute, West Oromia Meteorological Research Center, Jimma, Ethiopia
Meteorology and Hydrology Faculty, Arba Minch University, Arba Minch, Ethiopia
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