Oceanic Forcing of Sahel Rainfall on Interannual to Interdecadal Time Scales

  title={Oceanic Forcing of Sahel Rainfall on Interannual to Interdecadal Time Scales},
  author={Alessandra Giannini and Ramalingam Saravanan and Ping Chang},
  pages={1027 - 1030}
We present evidence, based on an ensemble of integrations with NSIPP1 (version 1 of the atmospheric general circulation model developed at NASA's Goddard Space Flight Center in the framework of the Seasonal-to-Interannual Prediction Project) forced only by the observed record of sea surface temperature from 1930 to 2000, to suggest that variability of rainfall in the Sahel results from the response of the African summer monsoon to oceanic forcing, amplified by land-atmosphere interaction. The… 
Oceanic forcing of the late 20th century Sahel drought
The Sahel region of Africa underwent a pronounced interdecadal drying trend in the latter half of the 20th century. In order to investigate this drying trend, several ensembles of numerical
Understanding Pacific Ocean influence on interannual precipitation variability in the Sahel
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Dynamics of the boreal summer African monsoon in the NSIPP1 atmospheric model
A nine-member ensemble of simulations with a state-of-the-art atmospheric model forced only by the observed record of sea surface temperature (SST) over 1930–2000 is shown to capture the dominant
Observation of oceanic origin of Sahel precipitation from space
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Moisture budget analysis of SST-driven decadal Sahel precipitation variability in the twentieth century
It is well known that the Sahel region of Africa is impacted by decadal scale variability in precipitation, driven by global sea surface temperatures. This work demonstrates that the National Center
Ocean Warming and Late-Twentieth-Century Sahel Drought and Recovery
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An Externally Forced Decadal Rainfall Seesaw Pattern Over the Sahel and Southeast Amazon
By analyzing observations and model simulations, here we show that there exists a significant anticorrelation on interannual to multidecadal time scales between the Sahel and southeast Amazon
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Given the pronounced warming in the Indian Ocean sea surface temperature (SST) during the second half of the twentieth century and the empirical relationship between the Indian Ocean SST and Sahel
Robust Sahel drought due to the Interdecadal Pacific Oscillation in CMIP5 simulations
Many studies address the Interdecadal Pacific Oscillation (IPO) as a modulator of climate in several regions all over the globe. However, very few suggest that it has an impact on Sahel rainfall


Influence of the Atlantic, Pacific and Indian Oceans on Sahel rainfall
Folland et al.1 have reported that persistently dry and wet periods of several years in the Sahel have been accompanied by global-scale patterns of sea-surface temperature (SST) anomaly. They also
Sahel rainfall and worldwide sea temperatures, 1901–85
Using the comprehensively quality-controlled Meteorological Office Historical Sea Surface Temperature data set (MOHSST)1,2 we show for the first time that persistently wet and dry periods in the
Enhancement of Interdecadal Climate Variability in the Sahel by Vegetation Interaction.
The role of naturally varying vegetation in influencing the climate variability in the West African Sahel is explored in a coupled atmosphere-land-vegetation model and interactive vegetation enhances the interdecadal variation substantially but can reduce year-to-year variability.
Mechanisms by Which Gulf of Guinea and Eastern North Atlantic Sea Surface Temperature Anomalies Can Influence African Rainfall
Abstract The sensitivity of precipitation over West Africa to sea surface temperature anomalies (SSTAs) in the Gulf of Guinea and the eastern North Atlantic is studied using a GCM. Results from nine
Tropical tropospheric temperature variations caused by ENSO and their influence on the remote tropical climate
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West African Monsoon Dynamics and Eastern Equatorial Atlantic and Pacific SST Anomalies (1970-88)
Abstract The Laboratoire de Meteorologie Dynamique atmospheric GCM is used to investigate relationships between West African monsoon dynamics and SST anomalies in the eastern equatorial Atlantic and
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An intermediate‐complexity atmospheric model coupled with a simple land‐surface model and a mixed‐layer ocean model is used to investigate the processes involved in an idealized monsoon occurring on
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Abstract Sub-Saharan West Africa (10–20°N) receives moisture from the tropical Atlantic via low-level south-westerly flow across the southwestern coast of West Africa. This paper utilizes a 1arge
Variability of summer rainfall over tropical north Africa (1906–92): Observations and modelling
The nature and causes of seasonal (July to September (JAS)) rainfall variability over tropical north Africa are investigated using a combination of empirical and modelling approaches. Concentration