HR: 15:45h
AN: PP53A-08 [Abstracts]
TI: A High Resolution Record of Recent Climate Change From Isla Isabela in the Gulf of California
AU: * Englebrecht, A
EM: aenglebrecht@berkeley.edu
AF: Department of Earth and Planetary Science, University of California Berkeley, Berkeley, CA
94720, United States
AU: Ingram, L
EM: ingram@eps.berkeley.edu
AF: Department of Earth and Planetary Science, University of California Berkeley, Berkeley, CA
94720, United States
AU: Ingram, L
EM: ingram@eps.berkeley.edu
AF: Department of Geography, University of California Berkeley, Berkeley, CA 94720, United
States
AU: Byrne, R
EM: arbyrne@berkeley.edu
AF: Department of Geography, University of California Berkeley, Berkeley, CA 94720, United
States
AU: Kienel, U
EM: ukienel@gfz-potsdam.de
AF: Department 3.3 Climate Dynamics and Sediments, GeoForschungsZentrum Potsdam
Telegrafenberg C 428, Potsdam, D- 13477, Germany
AU: Boehnel, H
EM: hboehnel@geociencias.unam.mx
AF: Centro de Geociencias, Universidad Nacional Autonoma de Mexico
Campus Juriquilla, Queretaro, CP 76230, Mexico
AU: Haug, G
EM: haug@gfz-potsdam.de
AF: Department 3.3 Climate Dynamics and Sediments, GeoForschungsZentrum Potsdam
Telegrafenberg C 324, Potsdam, D- 14473, Germany
AB:
Here we report on the stable isotopic composition (oxygen and carbon) and pollen content of seasonally
laminated lake sediments from Isla Isabela (21°52' N, 105°54' W) to reconstruct the history of recent
climate change in northwestern Mexico. Isabela crater lake is located approximately 30km offshore the state of
Nayarit, and is in the precipitation region of the Mexican Monsoon (also called North American Monsoon). Work
on an initial short core indicates coherent periodicities in δ13C and δ18O of bulk
inorganic carbonate throughout the past two centuries. Most notably, strong excursions in δ13C and
observable sedimentological changes occur at depths in the core corresponding to the years 1973-74, 1950s,
1860s, 1810s, and 1780s A.D.—recognized periods of historical drought in Mexico. Further downcore work
reveals additional periods of reduced water availability that may correspond to variations in the Mexican Monsoon.
DE: 1041 Stable isotope geochemistry (0454, 4870)
DE: 1051 Sedimentary geochemistry
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Joint Assembly