Collaborative: A multiple-technique approach for deconvolving tropical cyclone effects on Late Quaternary geomorphic change in arid southwestern North America.

Status Start Date End Date Locations
Extended Mar 1, 2018 Feb 29, 2020 All Counties
Director: Jose Luis Antinao
Other Researchers: Marissa Schorr (DEAS)
Funding: National Science Foundation
Objective: The project will perform: 1) A spatial identification and morphological, pedological (in collaboration with DRI), and sedimentological characterization of alluvial fan units in the Vizcaino and Colorado subregions of the Sonoran Desert. 2) develop a chronology of the identified alluvial fan units. 3) compare the Late Pleistocene chronology to other paleoclimate proxies and in particular to the record in Antinao et al (2016). 4) compare the Holocene chronology to a paleotempestological record on the Pacific coast (to be developed by this project through collaboration with LSU).
Approach: This project will compare a recently established alluvial fan chronology in southern Baja California, with newly-obtained alluvial fan and paleotempestological records. A Holocene paleotempestological record of overwash deposits in the Pacific coastal Vizcaino Desert will be developed for the first time. The inferred tropical storm activity will be compared with inland alluvial fan deposition in this area and in the northern Sonoran Desert, enabling discrimination of signals from different moisture sources, based on observed coastal and alluvial sedimentology, stratigraphy, and specific proxy records. Effects of different sources of moisture that drive sedimentation will be assessed by probing different time periods, and compared to independent paleoclimatic proxies. Bayesian analysis of luminescence, cosmogenic, and radiocarbon geochronology will improve age control precision.
Benefits: For the first time, a tropical cyclone landfall chronology covering the last few millennia will be developed for the Pacific coast of southwestern North America. This research has the potential to inform large-storm prediction scenarios for southern California and northwestern Mexico, which is relevant to hazards management for communities in need of risk assessment of rare and extreme events. The project will contribute to the training of the next generation of earth scientists using a tiered approach, with field-based collaboration of postdoctoral fellows, graduate and undergraduate students. This approach has been proven successful for inclusion of underrepresented minorities, enhanced also with planned research alongside Mexican collaborators and students. The project will provide unique broader educational experiences for grade-school students in Indiana and Arizona, through the use of technology to connect fieldwork and classrooms.