Past Climate Variability in South America and Surrounding Regions

This book features overviews and research papers dealing with South American climate variability from the Last Glacial Maximum to the Holocene. It presents an insight into dynamics of the past and provides a work of reference for data-model comparison.

South America is a unique place where a number of past climate archives are ava- able from tropical to high latitude regions. It thus offers a unique opportunity to explore past climate variability along a latitudinal transect from the Equator to Polar regions and to study climate teleconnections. Most climate records from tropical and subtropical South America for the past 20,000 years have been interpreted as local responses to shift in the mean position and intensity of the InterTropical Conv- gence Zone due to tropical and extratropical forcings or to changes in the South American Summer Monsoon. Further South, the role of the Southern Hemisphere westerly winds on global climate has been highly investigated with both paleodata and coupled climate models. However the regional response over South America during the last 20,000 years is much more variable from place to place than pre- ously thought. The factors that govern the spatial patterns of variability on millennial scale resolution are still to be understood. The question of past natural rates and ranges of climate conditions over South America is therefore of special relevance in this context since today millions of people live under climates where any changes in monsoon rainfall can lead to catastrophic consequences.

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This book groups together overviews and original research papers dealing with South American climate variability from the Last Glacial Maximum to the Holocene. The contributions deal with tropical, temperate and high latitudes climate variability in South America and in surrounding regions (including Pacific and Atlantic Oceans and Antarctica). It offers results obtained from both natural climate archives and recent simulations from coupled climate models. The objective is to propose a state of the art about our knowledge of past climate variability in South America. Specifically, this book aims at presenting the whole available observations and at discussing climate mechanisms, specifically the low to high latitude teleconnections on that continent which spreads out from the equator to Patagonia. It is written by an expert group of climate change scientists, and presents an insight into dynamics of the past and provides climate modellers with work of reference for data-model comparison. The book is an advanced but very readable text essential for all students and scientists interested in global environmental change.

Contenu
Can We Draw a Robust Picture of Last Glacial Maximum Climate Conditions in South America?.- Moisture Pattern During the Last Glacial Maximum in South America.- Orbital and Millennial-Scale Precipitation Changes in Brazil from Speleothem Records.- Chronologies of the Last Glacial Maximum and its Termination in the Andes (?1055°S) Based on Surface Exposure Dating.- Vegetation and Fire at the Last Glacial Maximum in Tropical South America.- Re-evaluation of Climate Change in Lowland Central America During the Last Glacial Maximum Using New Sediment Cores from Lake Petén Itzá, Guatemala.- Glacial to Holocene Paleoceanographic and Continental Paleoclimate Reconstructions Based on ODP Site 1233/GeoB 3313 Off Southern Chile.- The High Latitudes-Tropics and Tropics-Tropics Teleconnections over the Last Deglaciation and Last Glacial Maximum.- Teleconnections into South America from the Tropics and Extratropics on Interannual and Intraseasonal Timescales.- South American Climate Variability and Change: Remote and Regional Forcing Processes.- Sensitivity of South American Tropical Climate to Last Glacial Maximum Boundary Conditions: Focus on Teleconnections with Tropics and Extratropics.- Similarities and Discrepancies Between Andean Ice Cores Over the Last Deglaciation: Climate Implications.- Characteristics of the Holocene Climate. Focus on Global Events: Are They Widespread, Comparable and Synchroneous in South America?.- Mid-Holocene Climate of Tropical South America: A Model-Data Approach.- Millennial-Scale Ecological Changes in Tropical South America Since the Last Glacial Maximum.- The Nature and Origin of Decadal to Millennial Scale Climate Variability in the Southern Tropics of South America: The Holocene Record of Lago Umayo, Peru.- Hydrological Variability inSouth America Below the Tropic of Capricorn (Pampas and Patagonia, Argentina) During the Last 13.0 Ka.- Climate Change in Southern South America During the Last Two Millennia.- The Little Ice Age in Southern South America: Proxy and Model Based Evidence.