Characterization of the Interannual Variability of Precipitation and Streamflow in Tensift and Ksob Basins (Morocco) and Links with the NAO

Atmosphere

Nour-Eddine Laftouhi¹  Zineb Zamrane²  Gil Mahé²  Imen Turki³  Benoit Laignel³ 

[1] Faculty of Sciences Semlalia Marrakesh, Lab. GEOHYD, BP 2390 Marrakesh 40000, Morocco;Institut de recherche pour le développement, Unité mixte de recherche HydroSciences, University of Montpellier, 34095 Montpellier, France;Unité mixte de recherche Centre national de recherche scientifique 6143 Continental and Coastal Morphodynamics (M2C), University of Rouen, 76821 Mont-Saint-Aignan Cedex, France;

关键词: hydrological variability;    precipitation;    NAO;    wavelet analysis;    coherence analysis;    Morocco;    Tensift basin;    Ksob basin;   

DOI  :  10.3390/atmos7060084

来源: DOAJ

【 摘 要 】

The aim of this study is to understand the inter-annual hydrological variability (precipitation and streamflow) in the basins of the High Atlas in Morocco and to determine how climate fluctuations (represented by the North Atlantic Oscillation (NAO) climate index) are expressed in the hydrological system. To reach this objective, time series of precipitation and streamflow are processed as standardized anomalies and studied by continuous wavelet analysis and wavelet coherence analysis, which are particularly suitable for the study of unsteady processes. Wet and dry periods vary from one basin to another between three and five years. The wavelet analysis shows the existence of many bands of energy in most of the sub-basins, from annual to inter-annual scales regarding the precipitation and streamflow time series. These bands correspond to intervals of one year, 2–4 years, 4–8 years and 8–12 years. The wavelet coherence analysis shows a strong coherence between NAO/streamflow and precipitation/NAO identified at the inter-annual scale. Non-stationarity can be observed in the late 1980s, 1990s and 2000s. The contribution of the NAO is different from one basin to another ranging between 67% and 77%.

【 授权许可】

Unknown