Understanding Climate from Subantarctic Tree Rings

FIDEL A. ROIG; RICARDO VILLALBA

Late Cenozoic of Patagonia and Tierra del Fuego

Elsevier

Lugar: Amsterdam; Año: 2008; p. 411 - 435

In this contribution we review progress in interpretation of past climate characteristics from the coterminous Patagonia region based on tree-ring analysis. In this sence, we describe the significant contributions of dendroclimatology to our more precise knowledge of climate variations of the past centuries to millennia in Patagonia. Significant variations in temperature and precipitation have been identified for the last centuries. Particularly, a sustained positive trend during the 20th century has been shown in southern latitude temperature reconstructions. This warming trend appears to be unprecedent for at least the last few centuries. However, precipitation changes, as indicated from the long-term means in Patagonia during the 20th Century seem to indicate more pronounced intervals of dryness and wetness than a sustained trend. The exception is the downward trend in annual precipitation observed in the central Chile since the 1860?s to the present. Many of the growth patterns observed in living tree ring chronologies from Patagonia seem to be reproduced in chronologies constructed with ancient woods. A new framework provided by the analysis of floating subfossil tree-ring chronologies from glacial times suggest that common growth forcing factors influenced growth during contrasting climatic scenarios in Patagonia.