Seasonal-to-Interannual Variability of Southeastern South America in CMIP5 Decadal Hindcasts
Abstract
To face the increasing demand of near-term climate information, CMIP5 has designed a set of decadal hindcasts that explore the effect of initializing the models with information about the current state of the climate system. The idea is that some skill for the next year-to-decade may be gained if one can predict aspects of the natural internal variability of the climate system in addition to the anthropogenic trend. Preliminary results suggest that these hindcasts have some additional skill in the North Atlantic Ocean, which is likely associated with Atlantic multi-decadal variability, and in the tropical Pacific Ocean, which may reflect the decadal-scale component of ENSO. Southeastern South America (SESA) is a potentially interesting region to explore in these hindcasts, especially for precipitation. Over the 20th century this region experienced large trends, showed decadal-scale variability, and also exhibited strong seasonal-to-interannual variability, mainly due to an ENSO teleconnection. In this presentation we will discuss whether near-term climate projections for the area can benefit from initialized decadal hindcasts. In particular, we will explore if the hindcasts capture the main features of seasonal-to-interannual variability in SESA, even if we cannot expect to predict the exact timing of this variability years in advance. In particular, we examine the low-frequency modulation of ENSO-teleconnections in the region, and the extent to which these are tied to decadal-scale changes in the oceanic circulation.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFMGC43A0873G
- Keywords:
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- 1616 GLOBAL CHANGE / Climate variability;
- 1637 GLOBAL CHANGE / Regional climate change;
- 3305 ATMOSPHERIC PROCESSES / Climate change and variability;
- 3354 ATMOSPHERIC PROCESSES / Precipitation