HR: 09:20h
AN: A41B-08    [Abstracts]
TI: Interannual Variability of South American Climate in a Regional Climate Model and Observations
AU: * Seth, A
EM: seth@iri.columbia.edu
AF: Columbia University, 61 Route 9 W, Palisades, NY 10964 United States
AU: Rauscher, S
EM: rauscher@iri.columbia.edu
AF: Columbia University, 61 Route 9 W, Palisades, NY 10964 United States
AU: Camargo, S J
EM: suzana@iri.columbia.edu
AF: Columbia University, 61 Route 9 W, Palisades, NY 10964 United States
AB: The nested climate modeling approach is increasingly being used to address the need for higher spatial and temporal resolution climate information from seasonal forecasts and climate change scenarios. To evaluate this approach, an ensemble nested model climatology for South America is being performed using a regional climate model (RegCM3) driven with lateral boundary conditions from a general circulation model (GCM; ECHAM4) and NCEP/NCAR reanalyses, and using observed sea surface temperatures (SSTs) for the period 1982-2003. We will present preliminary results from the first 10 years of model integrations. The annual cycle and interannual variability of the nested model climate will be compared against both observations and the driving CGM. In particular, we will examine the climate features of the tropical and subtropical South American sector including the ITCZ, SACZ, and South Atlantic subtropical high and their relationships to moisture transport and continental rainfall and their representation in the RegCM and GCM. Discussion will focus on the ``added value'' of this dynamical downscaling methodology.
DE: 1655 Water cycles (1836)
DE: 1833 Hydroclimatology
DE: 1854 Precipitation (3354)
DE: 1610 Atmosphere (0315, 0325)
DE: 1620 Climate dynamics (3309)
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting