Projecting drought characteristics over East African basins at specific global warming levels

Nguvava, Mariam; Abiodun, Babatunde J.; Otieno, Francis O.

doi:10.1016/j.atmosres.2019.05.008

Cited by 63 publications

(40 citation statements)

References 78 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similarly, Gizaw and Gan (2017) suggested that East Africa will experience a drier climate in the 2050s and 2080s with an increase in drought‐prone areas calling for actionable policies geared toward adaptation and mitigation. Furthermore, the projected increase in drought over East Africa is in line with previous studies covering similar geographical settings (Cook et al, 2014b; Nguvava et al, 2019; Zhao & Dai, 2017). Using regional model simulations, Nguvava et al (2019) projected an increase in the intensity and frequency of droughts over large parts of East Africa.…”

Section: Discussionsupporting

confidence: 89%

“…The projected SPI/SPEI time series data also indicate that the effect of PET is a more important variable in detecting future drought risks than precipitation. Nguvava et al (2019) analyzed SPI and SPEI time series in East Africa, using CORDEX model setups and RCPs (4.5 and 8.5), and projected an increase in severity and frequency of SPEI as compared to SPI suggesting the magnitude and robustness of SPEI for drought projections. Using four drought indices Jiang et al (2014) revealed that the effects of climate change in drought conditions showed a temperature increase (2°C) suggesting the importance of the SPEI drought index.…”

Section: Resultsmentioning

confidence: 99%

“…Various studies (Ahmadalipour et al, 2017; S. Feng et al, 2017; Jeong et al, 2014; Nguvava et al, 2019; Spinoni et al, 2020) assessed drought in East Africa and beyond using SPI and SPEI that resulted in differences in magnitude and direction. For example, Nguvava et al (2019) revealed that SPEI has simulated higher drought magnitude as compared to SPI in East Africa and suggested an effective land management practices can reduce the amount of water loss through evaporation. Drought projections based on precipitation only would result in decreasing drought over the Horn of Africa from those based on both precipitation and PET (Spinoni et al, 2020).…”

Section: Discussionmentioning

confidence: 99%

“…According to Meza et al (2019) and Hagenlocher et al (2019) drought vulnerability and risk assessments across spatiotemporal scales have shown an increase consistent with increasing droughts suggesting a need for reducing social, environmental, and economic impacts of droughts by creating drought‐resilient societies. A study by Nguvava et al (2019) in East Africa indicated that incorporating PET in quantifying the severity of future drought projections is better than using only precipitation. According to Sheffield and Wood (2008), an increase in drought during the 21st century is primarily driven by increased evaporation from higher temperatures.…”

Section: Discussionmentioning

confidence: 99%

“…Therefore, evaluating the magnitude of the projected droughts and their impacts is very important over East Africa. Although some researches have been carried out to address this issue (e.g., Nguvava et al, 2019; Osima et al, 2018; Spinoni et al, 2020), the magnitude of how much the drought is projected and the way how those impacts would affect the society and the environment remain largely unexplored. Therefore, this study was designed to fill this gap by focusing on understanding of future drought severity levels (moderate, severe, and extreme), and characteristics (drought area, event, duration, frequency, and intensity) at different spatiotemporal scales.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Projected Impacts of Climate Change on Drought Patterns Over East Africa

et al. 2020

View full text Add to dashboard Cite

Investigation of the pressing impacts of climate change on drought is vital for sustainable societal and ecosystem functioning. The magnitude of how much the drought will change and the way how droughts would affect society and the environment are inadequately addressed over East Africa. This study aimed at assessing future drought changes using an ensemble of five Global Climate Models (GCMs) in the Coupled Model Intercomparison Project (CMIP5) over East Africa. To this end, drought characteristics were investigated under the Representative Concentration Pathways (RCPs) 2.6, 4.5, and 8.5 in the near term (the 2020s; 2011–2040), midcentury (2050s; 2041–2070), and end of century (2080s; 2071–2,100). The changes of the Standardized Precipitation Index (SPI) and Standardized Precipitation‐Evapotranspiration Index (SPEI) were first compared, and the SPEI was used for measuring future droughts as it showed stronger changes due to its inclusion of temperature effects. Drought area in East Africa is likely to increase at the end of the 21st century by 16%, 36%, and 54% under RCP 2.6, 4.5, and 8.5, respectively, with the areas affected by extreme drought increasing more rapidly than severe and moderate droughts. Spatially, drought event, duration, frequency and intensity would increase in Sudan, Tanzania, Somalia, and South Sudan, but generally decrease in Kenya, Uganda, and Ethiopian highlands. Results also confirm that drought changes over East Africa follow the “dry gets drier and wet gets wetter” paradigm. The findings provide important guidance for improving identification of causes, minimizing the impacts and enhancing the resilience to droughts in East Africa.

show abstract

Section: Discussionsupporting

confidence: 89%

Section: Resultsmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Projected Impacts of Climate Change on Drought Patterns Over East Africa

et al. 2020

View full text Add to dashboard Cite

show abstract

Projected temperature and precipitation changes using the LARS‐WG statistical downscaling model in the Shire River Basin, Malawi

Kavwenje

Zhao

Liang

et al. 2021

Intl Journal of Climatology

View full text Add to dashboard Cite

This study analyzes local‐scale temperature and precipitation projections in the Shire River Basin (SRB) in Malawi using 10 global circulation models (GCMs) available in the coupled model intercomparison project phase 5 (CMIP5), under two representative concentration pathways (RCP 4.5 and RCP 8.5). For nine stations in the study area, large‐scale maximum temperature (Tmax), minimum temperature (Tmin) and precipitation data from the selected GCMs were downscaled by the sixth version of the Long Ashton Research Station Weather Generator (LARS‐WG6). The mean seasonal and annual change projections for Tmax, Tmin and precipitation during two future periods, that is, the middle future (2041–2070) and late future (2071–2100) periods were analyzed. Modelling results demonstrated that the LARS‐WG model is capable of simulating temperature more accurately than precipitation in the SRB. All 10 GCMs revealed that continually rising temperatures are anticipated in the study area; however, the projected magnitude of change varied across GCMs and between RCPs. Generally, the increase in average Tmax and Tmin was observed to be higher under RCP 8.5 compared with RCP 4.5 due to unmitigated greenhouse gas emissions (GHGs). Future precipitation change results showed more complexity and uncertainty than for temperature; not all GCMs agree on whether there will be positive or negative changes in precipitation and no systematic variations under RCP4.5 and RCP8.5 were observed during the two future time period, illustrating that both GCMs and RCPs are important sources of the relatively large uncertainties in future precipitation projections in the SRB. Thus, this study indicated that uncertainties constrained by both GCMs and RCPs are crucial and need to always be considered when executing climate impact studies and adaptation, particularly at river basin level.

show abstract

Spatial patterns and temporal dynamics of drought in southern Ethiopia from 1981 to 2100

Mena,

Kenea,

Yate

2023

Intl Journal of Climatology

View full text Add to dashboard Cite

We assess the spatiotemporal characteristics of historical and projected future drought over southern Ethiopia using the Standardized Precipitation Evapotranspiration Index and the K‐means clustering method. Historical assessment is done for the period 1981–2018 while projected drought is analysed over two consecutive future periods, that is, 2021–2060 (near future) and 2061–2100 (far future). Projected drought events are identified under RCP 4.5 and 8.5 climate scenarios based on three RCMs selected after performance evaluation. Modified Mann–Kendall trend test is applied to determine trends and significance at the 5% significance level. The results reveal broadly diverse and heterogeneous spatiotemporal characteristics both over the historical and future periods. Droughts of various frequencies, durations, and magnitudes are observed amongst stations, while trends generally lack spatial coherence. The year 1984 is noted to be the driest year in the historical period while the years 1982, 2009, and 1991 are with the driest March–May (MAM), June–August (JJA), and September–November (SON) seasons, respectively. Compared to the historical period, the frequency, magnitude, and duration of drought events are projected to decrease in the near future and increase in the far future. The frequency of drought events in SON and JJA seasons are projected to increase in the near future and far future, respectively, under both scenarios. More number of station shows a wetting tendency in the historical period while more number of stations exhibit a drying tendency during the projected future periods under the two scenarios. Since complex drought characteristics are observed both in the historical and future periods, rigorous local‐scale drought monitoring and management is recommended.

show abstract

Projecting drought characteristics over East African basins at specific global warming levels

Cited by 63 publications

References 78 publications

Projected Impacts of Climate Change on Drought Patterns Over East Africa

Projected Impacts of Climate Change on Drought Patterns Over East Africa

Projected temperature and precipitation changes using the LARS‐WG statistical downscaling model in the Shire River Basin, Malawi

Spatial patterns and temporal dynamics of drought in southern Ethiopia from 1981 to 2100

Contact Info

Product

Resources

About