Matches in SemOpenAlex for { <https://semopenalex.org/work/W2116529903> ?p ?o ?g. }
- W2116529903 endingPage "1005" @default.
- W2116529903 startingPage "973" @default.
- W2116529903 abstract "A 47-year record (1951–1997) of gridded data covering Africa south of the Sahara was used to document the spatial and seasonal patterns of the correlation between precipitation and sea-surface temperatures (SST) in key tropical areas, as depicted by the NIÑO3, South Atlantic and North Atlantic indices. El Niño–Southern Oscillation (ENSO) is confirmed as playing a dominant part in northeastern, eastern and southern Africa. However, its impact is also found over the Sahel during the northern summer, and other parts of the Gulf of Guinea region outside this season, a hitherto poorly documented feature. Over these two areas, ENSO and Atlantic SST (predominantly South Atlantic) contribute to different parts of the rainfall variance. The correlation with South Atlantic SST appears as a south–north dipole (positive/negative correlation) which shifts northward following the Inter-tropical Convergence Zone (ITCZ) translation between the northern low-sun and high-sun periods. A typing of the seasonal correlation patterns and a mapping of the multiple correlation coefficients are carried out in order to synthesize the space–time impacts of the three SST indices. Decadal-scale changes affect the strength of the teleconnections with both Atlantic and East Pacific SST, as reflected for instance by a small rise of the correlation with the NIÑO3 index since 1970–1975 in the Sahel and southern Africa, and additional shifts for the Atlantic Ocean, but the main patterns remain generally apparent over the whole period. The circulation anomalies associated with the teleconnections were assessed using National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data. A study of the dataset accuracy in depicting long-term climatic variations revealed that a major shift, mainly artificial, is found in 1967–1968 in the time-series of most of the variables. The rest of the work thus concentrated on the 1968–1997 period. A number of changes in east–west circulation patterns have been found to be associated to ENSO variations. Over West Africa, El Niño events tend to result in enhanced northeasterlies/reduced monsoon flow, coupled to weakened upper easterlies, and hence dry conditions over West Africa close to the surface position of the ITCZ, in July–September, as well as January–March. Over the southwestern Indian Ocean, the positive equatorial temperature/geopotential height anomalies, which at 200 hPa accompany El Niño events, are conducive to an eastward shift of the mid-latitude upper troughs, thus being detrimental to summer rainfall over South Africa. Abnormally wet ‘short rains’ in East Africa can be accounted for by an ENSO-forced weakening of the equatorial Walker-type (east–west) cell which is found over the Indian Ocean during that season. By contrast, the impact of South Atlantic warmings is mostly shown in low-level dynamics, as exemplified by the weakened trades and monsoon flow which directly result in a southward shift of the ITCZ. The combination of ENSO and Atlantic SST anomalies are found to give rise to complex wind flow changes in the near-equatorial Atlantic. In addition to large-scale SST-forced atmospheric dynamics, a few regional atmospheric signals are found to explain residual parts of rainfall variance. For instance, a strengthening of the African Easterly Jet, or northerly wind anomalies across the Sahara, are shown to be related to drought conditions in the Sahel (July–September) and the Gulf of Guinea area (January–March), once the remote effect of SST anomalies is removed. Copyright © 2001 Royal Meteorological Society" @default.
- W2116529903 created "2016-06-24" @default.
- W2116529903 creator A5064106415 @default.
- W2116529903 creator A5074938844 @default.
- W2116529903 creator A5085293514 @default.
- W2116529903 date "2001-01-01" @default.
- W2116529903 modified "2023-10-17" @default.
- W2116529903 title "Seasonality and atmospheric dynamics of the teleconnection between African rainfall and tropical sea-surface temperature: Atlantic vs. ENSO" @default.
- W2116529903 cites W1434602508 @default.
- W2116529903 cites W156231230 @default.
- W2116529903 cites W1963675163 @default.
- W2116529903 cites W1965941316 @default.
- W2116529903 cites W1966780503 @default.
- W2116529903 cites W1970546048 @default.
- W2116529903 cites W1977343249 @default.
- W2116529903 cites W1983923793 @default.
- W2116529903 cites W1988245413 @default.
- W2116529903 cites W1989136259 @default.
- W2116529903 cites W1992456239 @default.
- W2116529903 cites W1993196883 @default.
- W2116529903 cites W1993924040 @default.
- W2116529903 cites W1994165184 @default.
- W2116529903 cites W1995133006 @default.
- W2116529903 cites W1997854900 @default.
- W2116529903 cites W2000270764 @default.
- W2116529903 cites W2001231422 @default.
- W2116529903 cites W2005019103 @default.
- W2116529903 cites W2006839567 @default.
- W2116529903 cites W2021408743 @default.
- W2116529903 cites W2021431193 @default.
- W2116529903 cites W2022160785 @default.
- W2116529903 cites W2023860630 @default.
- W2116529903 cites W2026259912 @default.
- W2116529903 cites W2026762905 @default.
- W2116529903 cites W2027672945 @default.
- W2116529903 cites W2031804827 @default.
- W2116529903 cites W2050766636 @default.
- W2116529903 cites W2056527387 @default.
- W2116529903 cites W2057641583 @default.
- W2116529903 cites W2058234865 @default.
- W2116529903 cites W2062125747 @default.
- W2116529903 cites W2075157927 @default.
- W2116529903 cites W2077167237 @default.
- W2116529903 cites W2079172128 @default.
- W2116529903 cites W2080475879 @default.
- W2116529903 cites W2081336416 @default.
- W2116529903 cites W2084359173 @default.
- W2116529903 cites W2085544245 @default.
- W2116529903 cites W2089318837 @default.
- W2116529903 cites W2093872841 @default.
- W2116529903 cites W2094096040 @default.
- W2116529903 cites W2112341777 @default.
- W2116529903 cites W2135554037 @default.
- W2116529903 cites W2137566659 @default.
- W2116529903 cites W2139221300 @default.
- W2116529903 cites W2146979626 @default.
- W2116529903 cites W2153573316 @default.
- W2116529903 cites W2154214068 @default.
- W2116529903 cites W2159511418 @default.
- W2116529903 cites W2163388917 @default.
- W2116529903 cites W2172553240 @default.
- W2116529903 cites W2173251738 @default.
- W2116529903 cites W2175105200 @default.
- W2116529903 cites W2176044148 @default.
- W2116529903 cites W2176224099 @default.
- W2116529903 cites W2178186723 @default.
- W2116529903 cites W2325312389 @default.
- W2116529903 cites W296118296 @default.
- W2116529903 cites W3111500917 @default.
- W2116529903 cites W4242481446 @default.
- W2116529903 doi "https://doi.org/10.1002/joc.673" @default.
- W2116529903 hasPublicationYear "2001" @default.
- W2116529903 type Work @default.
- W2116529903 sameAs 2116529903 @default.
- W2116529903 citedByCount "337" @default.
- W2116529903 countsByYear W21165299032012 @default.
- W2116529903 countsByYear W21165299032013 @default.
- W2116529903 countsByYear W21165299032014 @default.
- W2116529903 countsByYear W21165299032015 @default.
- W2116529903 countsByYear W21165299032016 @default.
- W2116529903 countsByYear W21165299032017 @default.
- W2116529903 countsByYear W21165299032018 @default.
- W2116529903 countsByYear W21165299032019 @default.
- W2116529903 countsByYear W21165299032020 @default.
- W2116529903 countsByYear W21165299032021 @default.
- W2116529903 countsByYear W21165299032022 @default.
- W2116529903 countsByYear W21165299032023 @default.
- W2116529903 crossrefType "journal-article" @default.
- W2116529903 hasAuthorship W2116529903A5064106415 @default.
- W2116529903 hasAuthorship W2116529903A5074938844 @default.
- W2116529903 hasAuthorship W2116529903A5085293514 @default.
- W2116529903 hasConcept C107054158 @default.
- W2116529903 hasConcept C111368507 @default.
- W2116529903 hasConcept C11308688 @default.
- W2116529903 hasConcept C123576220 @default.
- W2116529903 hasConcept C127313418 @default.
- W2116529903 hasConcept C127889277 @default.
- W2116529903 hasConcept C134097258 @default.