Jet stream dynamics, hydroclimate, and fire in California from 1600 CE to present

National Academy of Sciences (NAS) | March 4th, 2019

Moisture delivery in California is largely regulated by the strength and position of the North Pacific jet stream (NPJ), winter high-altitude winds that influence regiona

Moisture delivery in California is largely regulated by the strength and position of the North Pacific jet stream (NPJ), winter high-altitude winds that influence regional hydroclimate and forest fire during the following warm season. We use climate model simulations and paleoclimate data to reconstruct winter NPJ characteristics back to 1571 CE to identify the influence of NPJ behavior on moisture and forest fire extremes in California before and during the more recent period of fire suppression. Maximum zonal NPJ velocity is lower and northward shifted and has a larger latitudinal spread during presuppression dry and high-fire extremes. Conversely, maximum zonal NPJ is higher and southward shifted, with narrower latitudinal spread during wet and low-fire extremes. These NPJ, precipitation, and fire associations hold across pre–20th-century socioecological fire regimes, including Native American burning, postcontact disruption and native population decline, and intensification of forest use during the later 19th century. Precipitation extremes and NPJ behavior remain linked in the 20th and 21st centuries, but fire extremes become uncoupled due to fire suppression after 1900. Simulated future conditions in California include more wet-season moisture as rain (and less as snow), a longer fire season, and higher temperatures, leading to drier fire-season conditions independent of 21st-century precipitation changes. Assuming continuation of current fire management practices, thermodynamic warming is expected to override the dynamical influence of the NPJ on climate–fire relationships controlling fire extremes in California. Recent widespread fires in California in association with wet extremes may be early evidence of this change.

Joining Forces: Innovative Co-Funding to Enhance Corporate Water Stewardship Impact in the Colorado River Basin

Pacific Institute | May 16th, 2023

The premise of this paper is that co-funding with existing and emerging funding mechanisms can help corporations tackle more complex problems at more meaningful scales in

The premise of this paper is that co-funding with existing and emerging funding mechanisms can help corporations tackle more complex problems at more meaningful scales in the Colorado River Basin and beyond. Corporations often have more flexibility than other funders, particularly federal and state agencies, in deciding how to spend their water stewardship budgets. This flexibility is an important asset, allowing funding to be deployed strategically. This white paper defines innovative co-funding as the intentional and focused use of corporate water stewardship funding alongside other funders and funding sources in new ways that expand the impact of corporate spending.

Joint Report to the Legislature on the Department of Fish and Wildlife and State Water Resources Control Board pilot project to address the Environmental Impacts of Cannabis Cultivation (Watershed Enforcement Team)

California State Water Resources Control Board (SWRCB) | March 16th, 2015

This report is in response to the 2014-2015 Supplemental Report for item 3600-001-0001-Department of Fish and Wildlife (Department or CDFW), which provides the following

This report is in response to the 2014-2015 Supplemental Report for item 3600-001-0001-Department of Fish and Wildlife (Department or CDFW), which provides the following directive: “The Department of Finance shall report, on behalf of the Marijuana Task Force, on or before January 10, 2015, to the Assembly and Senate budget committees, on its recommendations to require marijuana producers growing under Proposition 215 protections, to comply with regular permitting, and with any need for regulatory changes to allow law enforcement to accompany regulators for site visits.” In this report, the Department and the State Water Resources Control Board (Water Board)1 provide an overview of the joint pilot project to address environmental degradation resulting from marijuana cultivation, a discussion of the agencies’ interaction with other state agencies, and a discussion of the program’s outcomes between August 2014 and February 1, 2015. This report also describes that the CDFW and the Water Board intend to require that marijuana producers growing on private lands comply with CDFW’s and the Water Boards’ existing and soon-to-be adopted permitting programs and current environmental protection laws. There is no need for a regulatory change that would allow law enforcement to accompany regulators on site visits as that authority currently exists.

Joshua Tree National Park: A History of Preserving the Desert

National Park Service (NPS) | March 16th, 2015

Judicial Missteps, Legislative Dysfunction, and the Public Trust Doctrine: Can two wrongs make it right?

Harvard University | December 19th, 2015

Professor Joseph Sax’s environmental law scholarship has inspired generations of lawyers and legal scholars, including my very first law review publication in 1987, whi

Professor Joseph Sax’s environmental law scholarship has inspired generations of lawyers and legal scholars, including my very first law review publication in 1987, which questioned the way that some public interest advocates were enlisting Sax’s seminal work on the public trust doctrine to champion environmentalist causes. In our last conversation not long before his passing, Joe asked me whether I still believed now what I wrote in 1987 with the benefit of almost three decades of hindsight. This essay expands on the answer I gave Joe that evening. The essay first acknowledges the significant ways in which I clearly fell short in anticipating trends in environmental law, and for that reason, I agree that my original thesis warrants revision—especially with regard to the role of the public trust doctrine as a viable basis for defeating regulatory takings challenges. Next, the Essay discusses how, by contrast, I would not change my thesis in other respects and why, for that reason, I question the efficacy of relying on atmospheric trust doctrine theories in litigation to address the pressing issue of global climate change. The Essay is especially critical of atmospheric trust doctrine advocacy that relies on unduly harsh and demeaning criticism of existing environmental law and the career public servants who strive for its effective implementation.

Just the Facts: Land, Water, and Agriculture in the Colorado River Basin

Babbitt Center for Land and Water Policy (Babbitt Center) | March 1st, 2022

Juvenile Production Estimate (JPE) Calculation and Use/Application of Survival Data from Acoustically-tagged Chinook Salmon Releases Report

Delta Stewardship Council (Delta Council) | February 21st, 2014

Each year, NOAA’s National Marine Fisheries Service (NMFS) estimates the number of juvenile winter-run Chinook salmon expected to enter the Delta. NMFS’ June 4, 2009

Each year, NOAA’s National Marine Fisheries Service (NMFS) estimates the number of juvenile winter-run Chinook salmon expected to enter the Delta. NMFS’ June 4, 2009, biological and conference opinion on the long-term operation of the Central Valley Project and State Water Project provides an incidental take limit on natural juvenile winter-run based on the juvenile production estimate.

Juvenile salmonids traverse coastal meta-nurseries that connect rivers via the sea

Ecological Society of America (ESA) | April 30th, 2025

Conventionally, juvenile salmonids are thought to migrate unidirectionally from freshwater systems to marine systems and therefore only inhabit natal drainages. Although

Conventionally, juvenile salmonids are thought to migrate unidirectionally from freshwater systems to marine systems and therefore only inhabit natal drainages. Although scattered evidence suggests juveniles can move bidirectionally between freshwater rivers and the ocean, including into non-natal drainages, such movements have never been documented with high replication. Here, we detected hundreds of movements of juvenile salmonids between drainages that involved 0–22% of cohort emigrants in Washington State and California. Individuals moved up to nine times and between drainages up to 70 km apart. These findings reveal a life-history type of salmonids whose remarkably complex migrations have gone unnoticed. Implicitly, juveniles may use any coastal freshwater habitat accessible from the sea and may not descend from spawning populations of drainages they inhabit. Consequently, typical conservation focused on natal drainages may overlook freshwater habitat elsewhere. A concept of coastal areas as meta-nurseries formed by multiple watersheds connected by the sea may accurately describe anadromous species’ habitat options and better inform management.

Kaweah Subbasin Probationary Hearing Draft Staff Report

California State Water Resources Control Board (SWRCB) | May 2nd, 2024

The State Water Board recognizes that local public agencies in the Kaweah Subbasin have made significant efforts since the passage of SGMA to form three groundwater susta

The State Water Board recognizes that local public agencies in the Kaweah Subbasin have made significant efforts since the passage of SGMA to form three groundwater sustainability agencies (GSAs) and then develop detailed technical and other information supporting the adoption and implementation of three groundwater sustainability plans (GSPs) for the subbasin. Despite those efforts, in January of 2020, DWR reviewed the three GSPs to determine if the GSPs met SGMA’s requirements and found the GSPs to be incomplete. Following revisions made by the GSAs in the subbasin, DWR reevaluated the GSPs in March of 2023, determined the GSPs to be inadequate, and referred the subbasin to the State Water Board, as required by SGMA. Consistent with SGMA, the State Water Board may now consider whether to designate the Kaweah Subbasin as a “probationary basin,” a term that is used in SGMA to describe a basin in the first stage of state intervention.  Click here for Water Board updates on hearings. A January 5, 2025 has been cancelled to allow more time to review updated groundwater sustainability plans.

Keeping up with the status of freshwater fishes: A California (USA) perspective

Conservation Science and Practice (Wiley) | May 29th, 2021