5EASM2: LINKING NEAR-TERM FUTURE CHANGES IN WEATHER AND HYDROCLIMATE IN WESTERN NORTH AMERICA TO ADAPTATION FOR ECOSYSTEM AND WATER MANAGEMENT
Lamont-Doherty Earth Observatory of Columbia University 61 Route 9W Palisades, NY 10964

10. Climate variability and change and Southwestern river flows

Causes of Interannual to Decadal Variability of Gila River Streamflow over the past Century - PDF

Gila

 

Flow data for the Gila River, New Mexico, shows peaks in the winter-spring (December-January-February-March-April-May), and summer (August-September). Winter flow is typically greater than summer flow, although large spikes are found to appear intermittently in summer values. The mechanisms responsible for the variability of the winter-spring and summer streamflow peaks are investigated by correlation of streamflow with precipitation and sea surface temperature for 1928 to 2012. Decadal variability in the flow record is also examined for a longer term perspective on Gila River streamflow. Results indicate a strong coupling between the winter-spring streamflow and winter-spring precipitation and winter-spring streamflow and with Pacific SST with El NiƱo conditions causing increased precipitation and streamflow. Decadal Pacific variability helps explain the transition from high winter flow in the late 20th century to lower flows in the most recent decade. The summer streamflow has a somewhat weaker correlation with summer precipitation and Pacific SST, and its variability is more likely influenced by local variability within the North American Monsoon. Tree ring-based reconstructions of the Palmer Drought Severity Index and the Standardized Precipitation Index indicate much more severe and extended periods of droughts and pluvials in past centuries as well as periods of concurrent winter and summer drought.

Keywords: streamflow decadal variability; drought; pluvials; treering; teleconnections; North American Monsoon

Climate model simulation of Rio Grande stream flow and projected changes for the 21st Century

REFERENCE
  • Pascolini-Campbell, M.A., R. Seager, D.S. Gutzler, B.I. Cook and D. Griffin, 2015: Causes of Interannual to decadal variability of Gila Riverstreamflow over the past century. J. Hydrology: Regional Studies, 3: 494-508. PDF