Skip to main content

Glen M MacDonald

Southern California relies heavily upon imported water from the Sacramento and Colorado river systems to augment local supplies and to mitigate the impacts of drought. In this paper a ‘perfect drought’ is defined as a prolonged drought that affects southern California, the Sacramento River basin and the upper Colorado River basin simultaneously. Examination of instrumental climate and discharge records shows that over the past century such perfect droughts do occur, but generally persist for less than five years. Perfect droughts that extend across all three areas are associated with anomalous upper-level high pressure off west coast and over western North America which is in turn associated with anomalously...
A key feature of anticipated 21st century droughts in Southwest North America is the concurrence of elevated temperatures and increased aridity. Instrumental records and paleoclimatic evidence for past prolonged drought in the Southwest that coincide with elevated temperatures can be assessed to provide insights on temperature-drought relations and to develop worst-case scenarios for the future. In particular, during the medieval period, ∼AD 900-1300, the Northern Hemisphere experienced temperatures warmer than all but the most recent decades. Paleoclimatic and model data indicate increased temperatures in western North America of approximately 1 °C over the long-term mean. This was a period of extensive...
thumbnail
In California, the near-shore area where the ocean meets the land is a highly productive yet sensitive region that supports a wealth of wildlife, including several native bird species. These saltmarshes, mudflats, and shallow bays are not only critical for wildlife, but they also provide economic and recreational benefits to local communities. Today, sea-level rise, more frequent and stronger storms, saltwater intrusion, and warming water temperatures are among the threats that are altering these important habitats. To support future planning and conservation of California’s near-shore habitats, researchers examined current weather patterns, elevations, tides, and sediments at these sites to see how they affect...
Categories: Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, Bolinas Lagoon, CA, CASC, California, All tags...
thumbnail
We examine instrumental meteorological records to compare recent precipitation regimes in the eastern and western Uinta Mountains region of Utah. The comparison demonstrates that, although the summer monsoon contributes a higher proportion of annual precipitation in the east, the two regions are significantly correlated in terms of precipitation variations including summer precipitation. Major droughts, such as the 1930s Dustbowl event, the 1976–1977 event, and the 1987–1989 event, are largely typified by strong decreases in winter precipitation, although deficits can extend into summer. Droughts generally impact the entire region when they occur. Unlike the Southwest and the Pacific Northwest, year-to-year...
View more...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.