Multi‐Scale Analysis of July (Hamle) Rainfall Failure as an Indicator of Drought and El Niño Events in Ethiopia: A Case Study of Borkena Watershed, Awash Basin.
Saved in:
| Title: | Multi‐Scale Analysis of July (Hamle) Rainfall Failure as an Indicator of Drought and El Niño Events in Ethiopia: A Case Study of Borkena Watershed, Awash Basin. |
|---|---|
| Authors: | Lakew, Haileyesus Belay1,2 (AUTHOR) h.lakew@cgiar.org, Taye, Meron Teferi1 (AUTHOR), Seid, Abdulkarim Hussien1 (AUTHOR) |
| Source: | International Journal of Climatology. Mar2026, Vol. 46 Issue 3, p1-14. 14p. |
| Subject Terms: | *Droughts, *Drought forecasting, *Water management, *Watersheds, El Niño, Rainfall reliability, Ethiopians |
| Geographic Terms: | Ethiopia |
| Abstract: | Drought has severe consequences for the livelihoods and economies of countries reliant on rainfed agriculture, such as Ethiopia. The Awash Basin, which experiences frequent droughts and water scarcity, requires effective water resource management. Identifying reliable drought indicators is crucial for early warning and mitigation. This study aims to determine the most relevant rainfall‐based indicator of historical meteorological drought in relation to El Niño events across multiple spatial and temporal scales. Using historical precipitation data from the CHIRPS dataset (1981–2021), the study analyses rainfall patterns at three spatial scales: the Awash Basin (110,000 km2), the Borkena sub‐basin (3250 km2), and local livelihood zones (36–927 km2). Monthly and dekadal (10‐day) temporal scales are considered, with rainfall classified into three dekads per month. Signal Detection Theory (SDT) metrics of True Positive Rate (TPR), False Positive Rate (FPR) and Competence (C) are used to evaluate the ability of total rainfall failure to detect historical droughts and El Niño years. Results indicate that July's total rainfall failure consistently aligns with historical droughts and El Niño events, achieving high detection performance (TPR > 70%, FPR < 30%, C > 40%) across all spatial scales. In the Borkena watershed, detection improves when focusing on the second and third dekads of July and the first dekad of August, corresponding to the Ethiopian month of Hamle, with maximum performance (TPR = 90%, FPR = 10%, C = 80%). These findings demonstrate that July rainfall failure, especially during Hamle, can serve as an in‐season early‐warning signal for meteorological drought, supporting timely response and water management. [ABSTRACT FROM AUTHOR] |
| Copyright of International Journal of Climatology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | GreenFILE |
| FullText | Text: Availability: 0 |
|---|---|
| Header | DbId: 8gh DbLabel: GreenFILE An: 192094472 AccessLevel: 6 PubType: Academic Journal PubTypeId: academicJournal PreciseRelevancyScore: 0 |
| IllustrationInfo | |
| Items | – Name: Title Label: Title Group: Ti Data: Multi‐Scale Analysis of July (Hamle) Rainfall Failure as an Indicator of Drought and El Niño Events in Ethiopia: A Case Study of Borkena Watershed, Awash Basin. – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AR" term="%22Lakew%2C+Haileyesus+Belay%22">Lakew, Haileyesus Belay</searchLink><relatesTo>1,2</relatesTo> (AUTHOR)<i> h.lakew@cgiar.org</i><br /><searchLink fieldCode="AR" term="%22Taye%2C+Meron+Teferi%22">Taye, Meron Teferi</searchLink><relatesTo>1</relatesTo> (AUTHOR)<br /><searchLink fieldCode="AR" term="%22Seid%2C+Abdulkarim+Hussien%22">Seid, Abdulkarim Hussien</searchLink><relatesTo>1</relatesTo> (AUTHOR) – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="JN" term="%22International+Journal+of+Climatology%22">International Journal of Climatology</searchLink>. Mar2026, Vol. 46 Issue 3, p1-14. 14p. – Name: Subject Label: Subject Terms Group: Su Data: *<searchLink fieldCode="DE" term="%22Droughts%22">Droughts</searchLink><br />*<searchLink fieldCode="DE" term="%22Drought+forecasting%22">Drought forecasting</searchLink><br />*<searchLink fieldCode="DE" term="%22Water+management%22">Water management</searchLink><br />*<searchLink fieldCode="DE" term="%22Watersheds%22">Watersheds</searchLink><br /><searchLink fieldCode="DE" term="%22El+Niño%22">El Niño</searchLink><br /><searchLink fieldCode="DE" term="%22Rainfall+reliability%22">Rainfall reliability</searchLink><br /><searchLink fieldCode="DE" term="%22Ethiopians%22">Ethiopians</searchLink> – Name: SubjectGeographic Label: Geographic Terms Group: Su Data: <searchLink fieldCode="DE" term="%22Ethiopia%22">Ethiopia</searchLink> – Name: Abstract Label: Abstract Group: Ab Data: Drought has severe consequences for the livelihoods and economies of countries reliant on rainfed agriculture, such as Ethiopia. The Awash Basin, which experiences frequent droughts and water scarcity, requires effective water resource management. Identifying reliable drought indicators is crucial for early warning and mitigation. This study aims to determine the most relevant rainfall‐based indicator of historical meteorological drought in relation to El Niño events across multiple spatial and temporal scales. Using historical precipitation data from the CHIRPS dataset (1981–2021), the study analyses rainfall patterns at three spatial scales: the Awash Basin (110,000 km2), the Borkena sub‐basin (3250 km2), and local livelihood zones (36–927 km2). Monthly and dekadal (10‐day) temporal scales are considered, with rainfall classified into three dekads per month. Signal Detection Theory (SDT) metrics of True Positive Rate (TPR), False Positive Rate (FPR) and Competence (C) are used to evaluate the ability of total rainfall failure to detect historical droughts and El Niño years. Results indicate that July's total rainfall failure consistently aligns with historical droughts and El Niño events, achieving high detection performance (TPR > 70%, FPR < 30%, C > 40%) across all spatial scales. In the Borkena watershed, detection improves when focusing on the second and third dekads of July and the first dekad of August, corresponding to the Ethiopian month of Hamle, with maximum performance (TPR = 90%, FPR = 10%, C = 80%). These findings demonstrate that July rainfall failure, especially during Hamle, can serve as an in‐season early‐warning signal for meteorological drought, supporting timely response and water management. [ABSTRACT FROM AUTHOR] – Name: AbstractSuppliedCopyright Label: Group: Ab Data: <i>Copyright of International Journal of Climatology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.) |
| PLink | https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=8gh&AN=192094472 |
| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1002/joc.70227 Languages: – Code: eng Text: English PhysicalDescription: Pagination: PageCount: 14 StartPage: 1 Subjects: – SubjectFull: Droughts Type: general – SubjectFull: Drought forecasting Type: general – SubjectFull: Water management Type: general – SubjectFull: Watersheds Type: general – SubjectFull: El Niño Type: general – SubjectFull: Rainfall reliability Type: general – SubjectFull: Ethiopians Type: general – SubjectFull: Ethiopia Type: general Titles: – TitleFull: Multi‐Scale Analysis of July (Hamle) Rainfall Failure as an Indicator of Drought and El Niño Events in Ethiopia: A Case Study of Borkena Watershed, Awash Basin. Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Lakew, Haileyesus Belay – PersonEntity: Name: NameFull: Taye, Meron Teferi – PersonEntity: Name: NameFull: Seid, Abdulkarim Hussien IsPartOfRelationships: – BibEntity: Dates: – D: 01 M: 03 Text: Mar2026 Type: published Y: 2026 Identifiers: – Type: issn-print Value: 08998418 Numbering: – Type: volume Value: 46 – Type: issue Value: 3 Titles: – TitleFull: International Journal of Climatology Type: main |
| ResultId | 1 |