Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria)
Northwest Algeria has experienced fluctuations in rainfall between the two decades 1940s and 1990s from positive to negative anomalies, which reflected a significant decline in rainfall during the mid-1970s. Therefore, further analyzing rainfall in this region is required for improving the strategie...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-03-01
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| Series: | Atmosphere |
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| Online Access: | https://www.mdpi.com/2073-4433/11/4/347 |
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| author | Hanane Bougara Kamila Baba Hamed Christian Borgemeister Bernhard Tischbein Navneet Kumar |
| author_facet | Hanane Bougara Kamila Baba Hamed Christian Borgemeister Bernhard Tischbein Navneet Kumar |
| author_sort | Hanane Bougara |
| collection | DOAJ |
| description | Northwest Algeria has experienced fluctuations in rainfall between the two decades 1940s and 1990s from positive to negative anomalies, which reflected a significant decline in rainfall during the mid-1970s. Therefore, further analyzing rainfall in this region is required for improving the strategies on water resource management. In this study, we complement previous studies by dealing with sub basins that were not previously addressed in Tafna basin (our study area located in Northwest Algeria), and by including additional statistical methods (Kruskal–Wallis test, Jonckheere-Terpstra test, and the Friedman test) that were not earlier reported on the large scale (Northwest Algeria). In order to analyse the homogeneity, trends, and stationarity in rainfall time series for nine rainfall stations over the period 1979–2011, we have used several statistical tests. The results showed an increasing trend for annual rainfall after the break detected in 2007 for Djbel Chouachi, Ouled Mimoun, Sidi Benkhala stations using Hubert, Pettitt, and Buishand tests. The Lee and Heghinian test has detected a break at the same year in 2007 for all stations except Sebdou, Beni Bahdel, and Hennaya stations, which have a break date in 1980. We have confirmed this increasing trend for rainfall with other trend detection methods such as Mann Kendall and Sen’s method that highlighted an upward trend for all the stations in the autumn season, which is mainly due to an increase in rainfall in September and October. On a monthly scale, the date of rupture is different from one station to another because the time series are not homogeneous. In addition, we have applied three tests enabling further results: (i) the Jonckheere-Terpstra test has detected an upward trend for two stations (Khemis and Hennaya), (ii) Friedman test has indicated the difference between the mean rank again with Khemis and Hennaya stations and the Merbeh station, (iii) according to the Kruskal-Wallis test, there have been no variance detected between all the rainfall stations. The increasing trend in rainfall may lead to a rise in stream flow and enhance potential floods risks in low-lying regions of the study area. |
| first_indexed | 2024-03-10T20:46:16Z |
| format | Article |
| id | doaj.art-c3312df1a7ae403281fb02e54aa1e5b5 |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-03-10T20:46:16Z |
| publishDate | 2020-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-c3312df1a7ae403281fb02e54aa1e5b52023-11-19T20:17:20ZengMDPI AGAtmosphere2073-44332020-03-0111434710.3390/atmos11040347Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria)Hanane Bougara0Kamila Baba Hamed1Christian Borgemeister2Bernhard Tischbein3Navneet Kumar4Faculty of Technology, University of Abou Bekr Belkaid, Tlemcen 13000, AlgeriaFaculty of Technology, University of Abou Bekr Belkaid, Tlemcen 13000, AlgeriaCenter for Development Research (ZEF), University of Bonn, 53113 Bonn, GermanyCenter for Development Research (ZEF), University of Bonn, 53113 Bonn, GermanyCenter for Development Research (ZEF), University of Bonn, 53113 Bonn, GermanyNorthwest Algeria has experienced fluctuations in rainfall between the two decades 1940s and 1990s from positive to negative anomalies, which reflected a significant decline in rainfall during the mid-1970s. Therefore, further analyzing rainfall in this region is required for improving the strategies on water resource management. In this study, we complement previous studies by dealing with sub basins that were not previously addressed in Tafna basin (our study area located in Northwest Algeria), and by including additional statistical methods (Kruskal–Wallis test, Jonckheere-Terpstra test, and the Friedman test) that were not earlier reported on the large scale (Northwest Algeria). In order to analyse the homogeneity, trends, and stationarity in rainfall time series for nine rainfall stations over the period 1979–2011, we have used several statistical tests. The results showed an increasing trend for annual rainfall after the break detected in 2007 for Djbel Chouachi, Ouled Mimoun, Sidi Benkhala stations using Hubert, Pettitt, and Buishand tests. The Lee and Heghinian test has detected a break at the same year in 2007 for all stations except Sebdou, Beni Bahdel, and Hennaya stations, which have a break date in 1980. We have confirmed this increasing trend for rainfall with other trend detection methods such as Mann Kendall and Sen’s method that highlighted an upward trend for all the stations in the autumn season, which is mainly due to an increase in rainfall in September and October. On a monthly scale, the date of rupture is different from one station to another because the time series are not homogeneous. In addition, we have applied three tests enabling further results: (i) the Jonckheere-Terpstra test has detected an upward trend for two stations (Khemis and Hennaya), (ii) Friedman test has indicated the difference between the mean rank again with Khemis and Hennaya stations and the Merbeh station, (iii) according to the Kruskal-Wallis test, there have been no variance detected between all the rainfall stations. The increasing trend in rainfall may lead to a rise in stream flow and enhance potential floods risks in low-lying regions of the study area.https://www.mdpi.com/2073-4433/11/4/347rainfall variabilitytrend analysisstatistical testwater resourceTafna basin |
| spellingShingle | Hanane Bougara Kamila Baba Hamed Christian Borgemeister Bernhard Tischbein Navneet Kumar Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria) Atmosphere rainfall variability trend analysis statistical test water resource Tafna basin |
| title | Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria) |
| title_full | Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria) |
| title_fullStr | Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria) |
| title_full_unstemmed | Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria) |
| title_short | Analyzing Trend and Variability of Rainfall in The Tafna Basin (Northwestern Algeria) |
| title_sort | analyzing trend and variability of rainfall in the tafna basin northwestern algeria |
| topic | rainfall variability trend analysis statistical test water resource Tafna basin |
| url | https://www.mdpi.com/2073-4433/11/4/347 |
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