Trends and variability of temperature and evaporation over the African continent: Relationships with precipitation

Onyutha, Charles

doi:10.20937/atm.52788

Cited by 14 publications

(7 citation statements)

References 68 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As temperature increases, PET is also expected to increase. This is because high temperature induces an increased amount of energy required to convert liquid water to water vapor [48]. Theoretically, the expected increase in evaporative demand per degree warming is at a globally varying rate of 1.5-4% according to the Clausius-Clapeyron relationship [49].…”

Section: Future Precipitation and Petmentioning

confidence: 99%

“…The increases in PET will generally be larger over the Upper Nile, Kyoga, and northern Albert than in the Victoria and the southern Albert. It is worth noting that the water required to meet the evaporation and transpiration demands is supplied by precipitation [48]). Hence, as precipitation increases, PET is also expected to increase.…”

Section: Future Precipitation and Petmentioning

confidence: 99%

See 1 more Smart Citation

Observed and Future Precipitation and Evapotranspiration in Water Management Zones of Uganda: CMIP6 Projections

et al. 2021

Self Cite

View full text Add to dashboard Cite

We used CMIP6 GCMs to quantify climate change impacts on precipitation and potential evapotranspiration (PET) across water management zones (WMZs) in Uganda. Future changes are assessed based on four Shared Socioeconomic Pathways (SSP) scenarios including SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 over the periods 2021–2040, 2041–2060, 2061–2080, and 2081–2100. Both precipitation and PET are generally projected to increase across all the WMZs. Annual PET in the 2030s, 2050s, 2070s, 2090s will increase in the ranges 1.1–4.0%, 4.8–7.9%, 5.1–11.8%, and 5.3–17.1%, respectively. For the respective periods, annual precipitation will increase in the ranges 4.0–7.8%, 7.8–12.5%, 7.9–19.9%, and 6.9–26.3%. The lower and upper limits of these change ranges for both precipitation and PET are, respectively, derived under SSP1-2.6 and SSP5-8.5 scenarios. Climate change will impact on PET or precipitation disproportionately across the WMZs. While the eastern WMZ (Kyoga) will experience the largest projected precipitation increase especially towards the end of the century, the southern WMZ (Victoria) exhibited the largest PET increase. Our findings are relevant for understanding hydrological impacts of climate change across Uganda, in the background of global warming. Thus, the water sector should devise and implement adaptation measures to impede future socioeconomic and environmental crises in the country.

show abstract

Section: Future Precipitation and Petmentioning

confidence: 99%

Section: Future Precipitation and Petmentioning

confidence: 99%

Observed and Future Precipitation and Evapotranspiration in Water Management Zones of Uganda: CMIP6 Projections

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Hope 2009;Verissimo 2020). Such warming would add extra heat into the atmosphere, and most of this heat would go into drying the continent (Feddema 1999;Lian et al 2021;Onyutha 2021). Hence, the warming would amplify the evaporative demand of the atmosphere, thus triggering natural droughts more quickly and making such droughts more intense and longer-lasting.…”

Section: Introductionmentioning

confidence: 99%

Potential impacts of stratospheric aerosol injection on drought risk managements over major river basins in Africa

et al. 2021

View full text Add to dashboard Cite

Most socio-economic activities in Africa depend on the continent’s river basins, but effectively managing drought risks over the basins in response to climate change remains a big challenge. While studies have shown that the stratospheric aerosol injection (SAI) intervention could mitigate temperature-related climate change impacts over Africa, there is a dearth of information on how the SAI intervention could influence drought characteristics and drought risk managements over the river basins. The present study thus examines the potential impacts of climate change and the SAI intervention on droughts and drought management over the major river basins in Africa. Multi-ensemble climate simulation datasets from the Stratospheric Aerosol Geoengineering Large Ensemble (GLENS) Project were analysed for the study. The Standardized Precipitation Evapotranspiration Index (SPEI) and the Standardized Precipitation Index (SPI) were used to characterize the upper and lower limits of future drought severity, respectively, over the basins. The SPEI is a function of rainfall and potential evapotranspiration, whereas the SPI is only a function of rainfall, so the difference between the two indices is influenced by atmospheric evaporative demand. The results of the study show that, while the SAI intervention, as simulated in GLENS, may offset the impacts of climate change on temperature and atmospheric evaporative demand, the level of SAI that compensates for temperature change would overcompensate for the impacts on precipitation and therefore impose a climate water balance deficit in the tropics. SAI would narrow the gaps between SPEI and SPI projections over the basins by reducing SPEI drought frequency through reduced temperature and atmospheric evaporative demand while increasing SPI drought frequency through reduced rainfall. The narrowing of this gap lowers the level of uncertainty regarding future changes in drought frequency, but nonetheless has implications for future drought management in the basins, because while SAI lowers the upper limit of the future drought stress, it also raises the lower limit of the drought stress.

show abstract

“…Three main climate descriptors were retrieved: average air temperature (WorldClim 1.2; [50]), precipitation (CHIRPS; [51]), and potential evapotranspiration (TERRACLI-MATE; [52]). These variables represent some of the most important variables for characterizing the climate effect on crops [4,[53][54][55][56]. Main details on data sources can be accessed in Table 2.…”

Section: Climate Datamentioning

confidence: 99%

Soil and Climate Characterization to Define Environments for Summer Crops in Senegal

Hernández

Faye

et al. 2021

Sustainability

View full text Add to dashboard Cite

Investigating soil and climate variability is critical to defining environments for field crops, understanding yield-limiting factors, and contributing to the sustainability and resilience of agro-ecosystems. Following this rationale, the aim of this study was to develop a soil–climate characterization to describe environmental constraints in the Senegal summer-crops region. For the soil database, 825 soil samples were collected characterizing pH, electrical conductivity (EC), phosphorus (P), potassium (K), cation exchange capacity (CEC), and total carbon (C) and nitrogen (N). For the climate, monthly temperature, precipitation, and evapotranspiration layers were retrieved from WorldClim 2.1, CHIRPS and TERRACLIMATE. The same analysis was applied individually to both databases. Briefly, a principal component analysis (PCA) was executed to summarize the spatial variability. The outcomes from the PCA were subjected to a spatial fuzzy c-means algorithm, delineating five soil and three climate homogeneous areas, accounting for 73% of the soil and 88% of the climate variation. To our knowledge, no previous studies were done with large soil databases since availability field data is often limited. The use of soil and climate data allowed the characterization of different areas and their main drivers. The use of this classification will assist in developing strategic planning for future land use and capability classifications.

show abstract

Trends and variability of temperature and evaporation over the African continent: Relationships with precipitation

Abstract: Highlights • Trends and variability in long-term (1991-2015) temperature, potential evapotranspiration (PET) and precipitation across Africa were assessed. • Africa experienced warming trends at an average rate of about 0.2°C per decade.

Cited by 14 publications

References 68 publications

Observed and Future Precipitation and Evapotranspiration in Water Management Zones of Uganda: CMIP6 Projections

Observed and Future Precipitation and Evapotranspiration in Water Management Zones of Uganda: CMIP6 Projections

Potential impacts of stratospheric aerosol injection on drought risk managements over major river basins in Africa

Soil and Climate Characterization to Define Environments for Summer Crops in Senegal

Contact Info

Product

Resources

About