Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence.
The negative impact of Upper Greater Horn of Africa's (UGHA) complex topography on drought characterization exacerbated by gauge density and model forcing parameters has not been investigated. In order to fill this gap, this study employs a combination of remotely sensed, in situ, and model pro...
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| Format: | Journal Article |
| Language: | English |
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ELSEVIER
2020
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| Online Access: | http://hdl.handle.net/20.500.11937/86610 |
| _version_ | 1848764844036063232 |
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| author | Agutu, N.O. Awange, Joseph Ndehedehe, C. Mwaniki, M. |
| author_facet | Agutu, N.O. Awange, Joseph Ndehedehe, C. Mwaniki, M. |
| author_sort | Agutu, N.O. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The negative impact of Upper Greater Horn of Africa's (UGHA) complex topography on drought characterization exacerbated by gauge density and model forcing parameters has not been investigated. In order to fill this gap, this study employs a combination of remotely sensed, in situ, and model products (1982–2013); precipitation (CHIRPS, GPCC, and CHIRP), soil moisture (ERA-Interim, MERRA-2, CPC, GLDAS, and FLDAS), vegetation condition index (VCI), and total water storage products (GRACE and MERRA-2) to (i) characterize drought, (ii) explore the inconsistencies in areas under drought due to topographical variations, gauge density, and model forcing parameters, and (iii), assess the effectiveness of various drought indicators over Ethiopia (a selected UGHA region with unique topographical variation). A 3-month time scale that sufficiently captures agricultural drought is employed to provide an indirect link to food security situation in this rain-dependent region. The spatio-temporal drought patterns across all the products are found to be dependent on topography of the region, at the same time, the inconsistencies in characterizing drought is found to be mainly driven by topographical variability (directly) and gauge density (inversely) for precipitation products while for soil moisture products, precipitation forcing parameters plays a major role. In addition, the inconsistencies are found to be higher under extreme and moderate droughts than severe droughts. The mean differences in the percentage of areas under drought and different drought intensities over the region are on average 15.87% and 6.16% (from precipitation products) and 12.65% and 5.20% (from soil moisture products), respectively. On the effectiveness of various indicators, for the duration under study, the following were found to be most suitable over Ethiopia; VCI, GPCC, ERA, CPC, and FLDAS. These results are critical in putting into perspective drought analysis outcomes from various products. |
| first_indexed | 2025-11-14T11:25:48Z |
| format | Journal Article |
| id | curtin-20.500.11937-86610 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:25:48Z |
| publishDate | 2020 |
| publisher | ELSEVIER |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-866102021-12-06T03:10:23Z Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence. Agutu, N.O. Awange, Joseph Ndehedehe, C. Mwaniki, M. Science & Technology Life Sciences & Biomedicine Environmental Sciences Environmental Sciences & Ecology Agricultural drought Effectiveness of drought indicators Total water storage VCI Standardized index Standardized soil moisture index STANDARDIZED PRECIPITATION INDEX SATELLITE RAINFALL PRODUCTS TERRESTRIAL WATER STORAGE SOIL-MOISTURE METEOROLOGICAL DROUGHT VARIABILITY CLIMATE REANALYSIS TEMPERATURE VALIDATION The negative impact of Upper Greater Horn of Africa's (UGHA) complex topography on drought characterization exacerbated by gauge density and model forcing parameters has not been investigated. In order to fill this gap, this study employs a combination of remotely sensed, in situ, and model products (1982–2013); precipitation (CHIRPS, GPCC, and CHIRP), soil moisture (ERA-Interim, MERRA-2, CPC, GLDAS, and FLDAS), vegetation condition index (VCI), and total water storage products (GRACE and MERRA-2) to (i) characterize drought, (ii) explore the inconsistencies in areas under drought due to topographical variations, gauge density, and model forcing parameters, and (iii), assess the effectiveness of various drought indicators over Ethiopia (a selected UGHA region with unique topographical variation). A 3-month time scale that sufficiently captures agricultural drought is employed to provide an indirect link to food security situation in this rain-dependent region. The spatio-temporal drought patterns across all the products are found to be dependent on topography of the region, at the same time, the inconsistencies in characterizing drought is found to be mainly driven by topographical variability (directly) and gauge density (inversely) for precipitation products while for soil moisture products, precipitation forcing parameters plays a major role. In addition, the inconsistencies are found to be higher under extreme and moderate droughts than severe droughts. The mean differences in the percentage of areas under drought and different drought intensities over the region are on average 15.87% and 6.16% (from precipitation products) and 12.65% and 5.20% (from soil moisture products), respectively. On the effectiveness of various indicators, for the duration under study, the following were found to be most suitable over Ethiopia; VCI, GPCC, ERA, CPC, and FLDAS. These results are critical in putting into perspective drought analysis outcomes from various products. 2020 Journal Article http://hdl.handle.net/20.500.11937/86610 10.1016/j.scitotenv.2019.135149 English ELSEVIER restricted |
| spellingShingle | Science & Technology Life Sciences & Biomedicine Environmental Sciences Environmental Sciences & Ecology Agricultural drought Effectiveness of drought indicators Total water storage VCI Standardized index Standardized soil moisture index STANDARDIZED PRECIPITATION INDEX SATELLITE RAINFALL PRODUCTS TERRESTRIAL WATER STORAGE SOIL-MOISTURE METEOROLOGICAL DROUGHT VARIABILITY CLIMATE REANALYSIS TEMPERATURE VALIDATION Agutu, N.O. Awange, Joseph Ndehedehe, C. Mwaniki, M. Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence. |
| title | Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence. |
| title_full | Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence. |
| title_fullStr | Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence. |
| title_full_unstemmed | Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence. |
| title_short | Consistency of agricultural drought characterization over Upper Greater Horn of Africa (1982–2013): Topographical, gauge density, and model forcing influence. |
| title_sort | consistency of agricultural drought characterization over upper greater horn of africa (1982–2013): topographical, gauge density, and model forcing influence. |
| topic | Science & Technology Life Sciences & Biomedicine Environmental Sciences Environmental Sciences & Ecology Agricultural drought Effectiveness of drought indicators Total water storage VCI Standardized index Standardized soil moisture index STANDARDIZED PRECIPITATION INDEX SATELLITE RAINFALL PRODUCTS TERRESTRIAL WATER STORAGE SOIL-MOISTURE METEOROLOGICAL DROUGHT VARIABILITY CLIMATE REANALYSIS TEMPERATURE VALIDATION |
| url | http://hdl.handle.net/20.500.11937/86610 |