| Full text | |
| Author(s): |
Total Authors: 2
|
| Affiliation: | [1] Univ Sao Paulo, Dept Atmospher Sci, BR-05508090 Sao Paulo - Brazil
[2] Univ Calif Santa Barbara, Inst Computat Earth Syst Sci, Santa Barbara, CA 93106 - USA
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Climate Dynamics; v. 33, n. 7-8, p. 893-916, DEC 2009. |
| Web of Science Citations: | 42 |
| Abstract | |
This study examines the variability of the South America monsoon system (SAMS) over tropical South America (SA). The onset, end, and total rainfall during the summer monsoon are investigated using precipitation pentad estimates from the global precipitation climatology project (GPCP) 1979-2006. Likewise, the variability of SAMS characteristics is examined in ten Intergovernmental Panel on Climate Change (IPCC) global coupled climate models in the twentieth century (1981-2000) and in a future scenario of global change (A1B) (2081-2100). It is shown that most IPCC models misrepresent the intertropical convergence zone and therefore do not capture the actual annual cycle of precipitation over the Amazon and northwest SA. Most models can correctly represent the spatiotemporal variability of the annual cycle of precipitation in central and eastern Brazil such as the correct phase of dry and wet seasons, onset dates, duration of rainy season and total accumulated precipitation during the summer monsoon for the twentieth century runs. Nevertheless, poor representation of the total monsoonal precipitation over the Amazon and northeast Brazil is observed in a large majority of the models. Overall, MI-ROC3.2-hires, MIROC3.2-medres and MRI-CGCM3.2.3 show the most realistic representation of SAMS's characteristics such as onset, duration, total monsoonal precipitation, and its interannual variability. On the other hand, ECHAM5, GFDL-CM2.0 and GFDL-CM2.1 have the least realistic representation of the same characteristics. For the A1B scenario the most coherent feature observed in the IPCC models is a reduction in precipitation over central-eastern Brazil during the summer monsoon, comparatively with the present climate. The IPCC models do not indicate statistically significant changes in SAMS onset and demise dates for the same scenario. (AU) | |
| FAPESP's process: | 06/53769-6 - Climatic extremes in the Southeast and Center-West of Brazil: the present climate and projections for the XXI Century |
| Grantee: | Rodrigo José Bombardi |
| Support Opportunities: | Scholarships in Brazil - Master |
| FAPESP's process: | 02/09289-9 - Biosphere-atmosphere interaction - Phase 2: cerrados and land use changes |
| Grantee: | Humberto Ribeiro da Rocha |
| Support Opportunities: | BIOTA-FAPESP Program - Thematic Grants |