Late 20th century attribution of drying trends in the Sahel from the Regional Climate Model (RegCM3)

摘要: Received 27 July 2005; revised 7 October accepted 19 published November 2005. [1] The RegCM3 has been integrated for the period of 1960–2002 using initial and lateral boundary conditions from NCEP re-analyses at 6-hour intervals. Greenhouse gas concentrations remain fixed land-use/soil properties are not altered. accurately portrays a trend wetter in 1960s to very dry 1980s. 1980s temperatures Sahel approximately 3K warmer than wet 1960s, caused by reduction precipitation clouds leading an increase net absorbed solar radiation surface. This anomalous warming maintains steepest meridional temperature gradient therefore African Easterly Jet lower latitudes. initiation starts June persists through August model simulations. appears be related weaker Tropical which may linked Indian Ocean over past several decades. Citation: Jenkins, G. S., A. T. Gaye, B. Sylla (2005), Late 20th century attribution drying trends Regional Climate Model (RegCM3), Geophys. Res. Lett., 32, L22705, doi:10.1029/2005GL024225.