HR: 12:05h
AN: U42B-08    [Abstracts]
TI: Tree Ring Chronologies in Mexico and Dendroclimatic and Ecological Applications
AU: * Villanueva-Diaz, J
EM: villanueva.jose@inifap.gob.mx
AF: INIFAP CENID-RASPA, Km 6.5 Margen Derecha del Canal Sacramento, Gomez Palacio, Dgo 35140, Mexico
AU: Cerano-Paredes, J
EM: cerano.julian@inifap.gob.mx
AF: INIFAP CENID-RASPA, Km 6.5 Margen Derecha del Canal Sacramento, Gomez Palacio, Dgo 35140, Mexico
AU: Stahle, D W
EM: dstahle@uark.edu
AF: University of Arkansas, 113 Ozark Hall, University of Arkansas, Fayetteville, Ark 72701, United States
AU: Therrell, M D
EM: matthew-therrell@uiowa.edu
AF: University of Virginia, 291 McCormick Rd. PO. Box 400123, Charlotesville, VA 22904-4123, United States
AU: Luckman, B H
EM: luckman@uwo.ca
AF: University of Western Ontario, The University of Western Ontario, London, Ont N6A 5C2, Canada
AB: The understanding of historic hydroclimate variability is basic to determine the impact of atmospheric circulatory patterns and to plan for a proper management of limited water resources and ecosystem conservation purposes. The objective of this study was to develop a network of tree-ring chronologies for climate reconstruction and to analyze the influence of the ENSO warm phase in northern Mexico by using the Tropical Rainfall Index. Climatic sensitive tree-ring chronologies were developed in mountain ranges and riparian ecosystems of the Sierras Madre Oriental and Occidental, and central Mexico. A grid of over 30 new Douglas-fir, baldcypress, and pinyon pine chronologies were developed and seasonal winter-spring and summer precipitation reconstructions have been produced for northern and central Mexico. The seasonal winter-spring precipitation reconstructions extended 353 years (1450 - 2002) and 530 years (1472 - 2002) for Chihuahua, 228 years (1765 - 1993) and 504 years (1500 - 2003) for Durango, 602 years (1400 - 2002) for Nuevo Leon, 522 years (1474 - 1995) for Tamaulipas; and 342 years (1659 - 2001) and 410 years (1595 - 2004) for Coahuila. Some of the low frequency events were specific for each reconstruction, but common low frequency events (decadal resolution) were present in most of the reconstructions; specific cases are the droughts of the 1780s, 1810s, 1860s, 1870s, 1950s, and 1990s; and the wet episodes of the 1820s, 1830s, and 1890s.Trends in dry or wet periods were disrupted by above or below normal precipitation as affected by the ENSO phenomena, especially in the winter- spring period when this circulatory pattern produced in times abundant rains in northern Mexico. However, the ENSO influence on winter-spring precipitation has fluctuated through time. Cold fronts and hurricanes impacting the Gulf of Mexico may explain some of the hydrological behavior detected for northeastern Mexico. These results indicate that winter-spring hydroclimate variability in northern Mexico is influenced by a range of atmospheric circulatory patterns, and a greater grid of tree-ring chronologies should be developed to better explain climatic variability in this region. Currently, a couple of summer precipitation reconstructions have been developed and others are in process, but future research will focus on this issue. Summer rainfall represents over 70% of the annual precipitation in Mexico and provides water for agriculture, forest productivity, and other uses. On the other hand, fire frequency and forest dynamic studies are in process for restoration and conservation purposes.
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1620 Climate dynamics (0429, 3309)
DE: 4920 Dendrochronology
DE: 4922 El Nino (4522)
DE: 4950 Paleoecology
SC: Union [U]
MN: 2007 Joint Assembly