Accession Number:

ADA509715

Title:

Intraseasonal Variability Associated with Summer Precipitation Over South America Simulated by 14 IPCC AR4 Coupled GCMs

Descriptive Note:

Journal article

Corporate Author:

NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV

Report Date:

2009-09-01

Pagination or Media Count:

25.0

Abstract:

This study evaluates the intraseasonal variability associated with summer precipitation over South America in 14 coupled general circulation models GCMs participating in the Intergovernmental Panel on Climate Change IPCC Fourth Assessment Report AR4. Eight years of each models twentieth-century climate simulation are analyzed. Two dominant intraseasonal bands associated with summer precipitation over South America are focused on the 40- and the 22 day band. The results show that in the southern summer November-April, most of the models underestimate seasonal mean precipitation over central-east Brazil, northeast Brazil, and the South Atlantic convergence zone SAC2, while the Atlantic intertropical convergence zone ITCZ is shifted southward of its observed position. It is found that models with some form of moisture convective trigger tend to produce large variances for the intraseasonal bands.

Subject Categories:

  • Meteorology
  • Geography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE