Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of Ethiopia
A composite analysis is used to evaluate the teleconnections between the long term (June- August) rainfall anomalies with east and west phases of quasi-biennial oscillation (QBO) in the stratospheric zonal winds from 1979–2017. Applying the lower equatorial stratospheric zonal wind index in JJA rain...
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AIMS Press
2021-05-01
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| Series: | AIMS Environmental Science |
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| Online Access: | http://www.aimspress.com/article/doi/10.3934/environsci.2021013?viewType=HTML |
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| author | Abebe Kebede Habtegebreal Abebaw Bizuneh Alemu U. Jaya Prakash Raju |
| author_facet | Abebe Kebede Habtegebreal Abebaw Bizuneh Alemu U. Jaya Prakash Raju |
| author_sort | Abebe Kebede Habtegebreal |
| collection | DOAJ |
| description | A composite analysis is used to evaluate the teleconnections between the long term (June- August) rainfall anomalies with east and west phases of quasi-biennial oscillation (QBO) in the stratospheric zonal winds from 1979–2017. Applying the lower equatorial stratospheric zonal wind index in JJA rainfall prediction is based on its tendency to persist for several months after the phase change from easterly to westerly and vice versa. Below normal condition rainfall used to coin drought. This study is important because, the Upper Blue Nile region is one of the most inviting areas for different activities like agriculture and hydroelectric power; therefore, timely prediction of June-August rainfall serves farmers and other concerned sectors. The aim of this analysis is to establish the global signal quasi-biennial oscillation contribution alone at different time lags and its association among Southern Oscillation Index (SOI) for estimation June-August rainfall of the Upper Blue Nile. The rainfall used as predictand while quasi-biennial oscillation & SOI datasets are used as predictors in regression model after testing collinearity of these two independent variables. Performance of regression model and actual value is tested by using statistical techniques: Root Mean Square Error, Mean Absolute Error and bias. The performance is seen reasonably high between actual and estimated values show strong agreement. |
| first_indexed | 2024-12-19T17:25:33Z |
| format | Article |
| id | doaj.art-490d804341f9406c8e5a921962fc2146 |
| institution | Directory Open Access Journal |
| issn | 2372-0352 |
| language | English |
| last_indexed | 2024-12-19T17:25:33Z |
| publishDate | 2021-05-01 |
| publisher | AIMS Press |
| record_format | Article |
| series | AIMS Environmental Science |
| spelling | doaj.art-490d804341f9406c8e5a921962fc21462022-12-21T20:12:34ZengAIMS PressAIMS Environmental Science2372-03522021-05-018319020310.3934/environsci.2021013Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of EthiopiaAbebe Kebede Habtegebreal0Abebaw Bizuneh Alemu1U. Jaya Prakash Raju 21. Arba Minch University, Water Technology Institute, Meteorology and Hydrology Faculty, Ethiopia2. Bahir Dar University, Collage of Science, Department of Physics, Ethiopia 3. Ethiopian Institute of Textile and Fashion Technology, Basic Engineering & Science Research and Innovation Center, Ethiopia2. Bahir Dar University, Collage of Science, Department of Physics, EthiopiaA composite analysis is used to evaluate the teleconnections between the long term (June- August) rainfall anomalies with east and west phases of quasi-biennial oscillation (QBO) in the stratospheric zonal winds from 1979–2017. Applying the lower equatorial stratospheric zonal wind index in JJA rainfall prediction is based on its tendency to persist for several months after the phase change from easterly to westerly and vice versa. Below normal condition rainfall used to coin drought. This study is important because, the Upper Blue Nile region is one of the most inviting areas for different activities like agriculture and hydroelectric power; therefore, timely prediction of June-August rainfall serves farmers and other concerned sectors. The aim of this analysis is to establish the global signal quasi-biennial oscillation contribution alone at different time lags and its association among Southern Oscillation Index (SOI) for estimation June-August rainfall of the Upper Blue Nile. The rainfall used as predictand while quasi-biennial oscillation & SOI datasets are used as predictors in regression model after testing collinearity of these two independent variables. Performance of regression model and actual value is tested by using statistical techniques: Root Mean Square Error, Mean Absolute Error and bias. The performance is seen reasonably high between actual and estimated values show strong agreement.http://www.aimspress.com/article/doi/10.3934/environsci.2021013?viewType=HTMLteleconnectionzonal windphase changesoiqbo |
| spellingShingle | Abebe Kebede Habtegebreal Abebaw Bizuneh Alemu U. Jaya Prakash Raju Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of Ethiopia AIMS Environmental Science teleconnection zonal wind phase change soi qbo |
| title | Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of Ethiopia |
| title_full | Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of Ethiopia |
| title_fullStr | Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of Ethiopia |
| title_full_unstemmed | Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of Ethiopia |
| title_short | Examining the Role of Quasi-biennial Oscillation on Rainfall patterns over Upper Blue Nile Basin of Ethiopia |
| title_sort | examining the role of quasi biennial oscillation on rainfall patterns over upper blue nile basin of ethiopia |
| topic | teleconnection zonal wind phase change soi qbo |
| url | http://www.aimspress.com/article/doi/10.3934/environsci.2021013?viewType=HTML |
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