HR: 10:35h
AN: U42B-02    [Abstracts]
TI: Preliminary spatial Standardized Precipitation Index (SPI) drought reconstructions for central and northern Mexico
AU: * Gutierrez-Garcia, G
EM: genarog@email.arizona.edu
AF: University of Arizona, 825 E. 5th APT 417, Tucson, AZ 85719, United States
AU: Mendez, J M
EM: matias@atmosfera.unam.mx
AF: Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior s/n, Ciudad Universitaria Del. Coyoacan, Mexico D.F., 04510, Mexico
AU: Magana, V
EM: victormr@servidor.unam.mx
AF: Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior s/n, Ciudad Universitaria Del. Coyoacan, Mexico D.F., 04510, Mexico
AU: Villanueva-Diaz, J
EM: villanueva.jose@inifap.gob.mx
AF: CENID-RASPA, Instituto Nacional de Investigaciones Forestales y Agropecuarias, Km. 6.5 margen derecha del Canal de Sacramento, Gomez Palacio, Dgo, 35140, Mexico
AB: We developed a spatial drought reconstruction of the Standardized Precipitation Index (SPI) for northern and central Mexico based on the relationship between tree growth and climate. Many previous tree-rings studies have successfully reconstructed drought indices as Palmer Drought Severity Index (PDSI), although SPI has become a widely accepted drought index; to our knowledge no SPI reconstructions have been developed using tree-ring chronologies over our study region. The methodology used in this work was the Point by Point Regression (PPR). The data set used was a network of tree-ring chronologies for Mexico and south United States and a 7-month Standardized Precipitation Index (SPI) for the season November - May. The observed SPI was based on the Pearson Type III distribution (Guttman 1999), calculated from a 1-degree monthly precipitation dataset (Chen et al 2002). In order to maximize the number of tree-ring chronologies we set our calibration and reconstruction periods for 1948-1985 and 1801- 1985, respectively. According with our analysis, El Nino events are mainly associated with wetter condition over northern Mexico, while La Nina events are characterized by dry conditions. This reconstruction reproduces the 1950s drought which affected most of northern Mexico, the Great Plains and the southwestern United States. Results are compared with other reconstructed gridded drought indices available for the same area (Cook et al 2004).
DE: 1812 Drought
DE: 4920 Dendrochronology
SC: Union [U]
MN: 2007 Joint Assembly