Southwest

The distribution and abundance of cheatgrass, an invasive annual grass native to Eurasia, has increased substantially across the Intermountain West, including the Great Basin. Cheatgrass is highly flammable, and as it has expanded, the extent and frequency of fire in the Great Basin has increased by as much as 200%. These changes in fire regimes are associated with loss of the native...

California’s Central Valley is a nexus for water resources in the state, draining the Sacramento and San Joaquin River watersheds. Urban centers, agricultural operations, and the environment all compete for limited water, and demand is expected to only increase as the population grows and agriculture intensifies. At the same time, the water supply is projected to decrease as temperatures...

This project aimed to contribute to effective decision making in the region for the scientific community and general public. Resource managers in the Great Basin are dealing with significant questions regarding how best to make decisions in the natural and human systems in response to climate change. Vulnerability assessments and other tools are used for climate change adaptation, but...

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...

Streamflow in the Colorado River is heavily influenced by high-elevation snowpack. Warming temperatures in spring can reduce snow-fed flows, with serious implications for the water supplies that support communities and wildlife. While it is already well-known that precipitation has a significant influence on river flow, recent observations suggest that temperature and the amount of water...

There is a growing realization that current warming trends may be associated with increases in the size, frequency, and severity of forest fires in the West. While rising temperatures can create drought conditions that favor severe fires, it is also possible that drought limits the ability of trees to survive a fire. During a drought, there is less water available for trees and more...

In the southwestern United States, droughts of 10 or more years are projected to become more frequent by 2100. It also is projected that there will be fewer wet days per year, with more precipitation falling on those wet days. Such climatic extremes can strongly affect wild animals and plants, ecosystems, and humans. In the Southwest, more frequent and intense storms may negatively...

The majority of the West Coast’s most extreme storms have been linked to atmospheric rivers, a meteorological phenomenon in which large amounts of moisture are carried in narrow bands from over the Pacific Ocean to western North America. While weak atmospheric rivers are critical providers of winter rain and snow, stronger events can cause extreme flooding, mudslides, and avalanches –...

In the Southwestern U.S., rising temperatures and changing precipitation patterns are resulting in changes such as more frequent and severe wildfires and prolonged drought. Natural resource managers striving to make decisions in the face of these changing conditions can benefit from information on past, present, and future climate. While an array of climate assessments are available, it...

Few evaluations of actual collaborative science or co-production processes have been undertaken that can point to specific outcomes for either resource management or science decisions. Project researchers will assess a sample of collaborative Southwest Climate Science Center (SW CSC) funded research projects in order to evaluate the approaches used by SW CSC investigators to collaborate...

Natural climate variability can obscure or enhance long-term trends in experienced weather due to climate change. This can happen temporarily on timescales of a season to several years to a decade or two. Natural variability is poorly described and attributed to specific causes, contributing to uncertainty and misunderstandings about the nature of climate change that stakeholders and...

This project links climate, hydrological, and ecological changes over the next 30 years in a Great Basin watershed. In recent years, climate variability on annual and decadal time scales has been recognized as greater than commonly perceived with increasing impacts on ecosystems and available water resources. Changes in vegetation distribution, composition and productivity resulting from...