Potential Impacts of Reduced Inflows to the Salton Sea: Forecasting Non-market Damages

American Water Resources Association (AWRA) | September 28th, 2022

Potential local extirpation of an imperiled freshwater mussel population from wildfire runoff

Western North America Naturalist | December 17th, 2022

Potter Valley Hydroelectric Project (FERC Project No. 77) Draft Application for Surrender of License and Application for Non-Project Use of Project Lands

Pacific Gas & Electric Company (PG&E) | January 27th, 2025

Click here for a California State Water Resources Control Board page about FERC Project 77 Pacific Gas & Electric Company (PG&E) has prepared a Draft Surrender

Click here for a California State Water Resources Control Board page about FERC Project 77 Pacific Gas & Electric Company (PG&E) has prepared a Draft Surrender Application and Conceptual Decommissioning Plan (Surrender Application) for the Potter Valley Hydroelectric Project (Federal Energy Regulatory Commission [FERC or Commission] Project No. 77) (Project) consistent with 18 Code of Federal Regulations (CFR) Section (§) 6.1. PG&E’s goals upon conclusion of the decommissioning process are to (1) remove the Project facilities and features including but not limited to Scott Dam and Cape Horn Dam, (2) remove the Project from FERC and Division of Safety of Dams jurisdiction; and (3) no longer operate or maintain the Project and Project features in the future. Parts 1 and 2 -- Part one or click "Get Document" below Parts 1 and 2 -- Part two

PPIC Statewide Survey: Californians and the Environment

Public Policy Institute of California (PPIC) | July 28th, 2022

With California facing a severe drought and wildfire season, public awareness has risen of the impact of climate change as well as state policies to reduce greenhouse gas

With California facing a severe drought and wildfire season, public awareness has risen of the impact of climate change as well as state policies to reduce greenhouse gas emissions. A sharp increase in petroleum prices has led to discussions about expanding oil production and renewable energy sources. These are among the key findings of a statewide survey on environmental issues conducted by the Public Policy Institute of California from July 8 to 15, 2022.

PPIC Statewide Survey: Californians and the Environment

Public Policy Institute of California (PPIC) | August 8th, 2024

Californians have been facing a record heat wave and wildfires across the state this summer. The state’s multibillion-dollar budget deficit prompted spending cuts for

Californians have been facing a record heat wave and wildfires across the state this summer. The state’s multibillion-dollar budget deficit prompted spending cuts for climate and energy programs. In response, the legislature approved a $10 billion state bond for the November ballot that asks voters to approve more funding for drought, floods, wildfires, coastal resilience, and extreme heat mitigation. The deep partisan divide on climate and energy policies surfaced in the presidential debate on June 27. These are the key findings of the Californians and the Environment survey on local, state, and national issues and coastal and inland topics that was conducted June 24–July 2, 2024.

Practical methods to find polluted areas in urban stormwater catchments to support management actions

San Francisco Estuary Institute (SFEI) | January 14th, 2022

Precipitation Enhancement (Resource Management Strategy)

California Department of Water Resources (DWR) | July 29th, 2016

Precipitation enhancement, commonly called “cloud seeding,” artificially stimulates clouds to produce more rainfall or snowfall than they would produce naturally. Clo

Precipitation enhancement, commonly called “cloud seeding,” artificially stimulates clouds to produce more rainfall or snowfall than they would produce naturally. Cloud seeding injects substances into the clouds that enable snowflakes and raindrops to form more easily. Precipitation enhancement is the one form of weather modification done in California. Forms conducted in other states include hail suppression (reducing the formation of large, damaging hailstones) and fog dispersal (when fog is below freezing temperature). (There are some unconfirmed reports of hail suppression attempts in the San Joaquin Valley, using hail cannons, but the scientific basis for this method is dubious.) Winter orographic cloud seeding (cloud seeding where wind blows over a mountain range, thereby causing clouds and rain or snow by lifting the air) has been practiced in California since the early 1950s. Most of the projects are along the central and southern Sierra Nevada, with some in the Coast Ranges. The projects generally use silver iodide as the active seeding agent, supplemented by dry ice if aerial seeding is done. Silver iodide can be applied from ground generators or from airplanes. Occasionally, other agents, such as liquid propane, have been used. In recent years, some projects have been trying hygroscopic materials (substances that take up water from the air) as supplemental seeding agents. Most rain and snow enhancement projects are long-term projects that operate in all or most years. A few, such as Monterey County’s project, only ran for one or two seasons. Historically, the number of operating projects has increased during droughts, up to 20 projects in 1991, but has leveled off at about a dozen in wet or normal water years. Most of the agencies or districts doing precipitation enhancement projects suspend operations during very wet years once enough snow has accumulated to meet their water needs.

Precipitation History of the Mojave Desert Region, 1893–2001

U.S. Geological Survey (USGS) | July 1st, 2004

The Mojave Desert region covers 152,000 square km of the Southwestern United States. Recent studies by U.S. Geological Survey (USGS) and other scientists suggest

The Mojave Desert region covers 152,000 square km of the Southwestern United States. Recent studies by U.S. Geological Survey (USGS) and other scientists suggest that the region may become drier for the next 2 to 3 decades, in a pattern similar to mid-20th century dry conditions. Because the region’s population has increased rapidly since the mid-1950s, a repeat of such a dry episode could have severe consequences not only for residents but also for the desert’s diverse and fragile ecosystems.

Precipitation in a warming world: Assessing projected hydro-climate changes in California and other Mediterranean climate regions

Nature Portfolio (Springer Nature) | September 7th, 2017

In most Mediterranean climate (MedClim) regions around the world, global climate models (GCMs) consistently project drier futures. In California, however, proj

In most Mediterranean climate (MedClim) regions around the world, global climate models (GCMs) consistently project drier futures. In California, however, projections of changes in annual precipitation are inconsistent. Analysis of daily precipitation in 30 GCMs reveals patterns in projected hydrometeorology over each of the five MedClm regions globally and helps disentangle their causes. MedClim regions, except California, are expected to dry via decreased frequency of winter precipitation. Frequencies of extreme precipitation, however, are projected to increase over the two MedClim regions of the Northern Hemisphere where projected warming is strongest. The increase in heavy and extreme precipitation is particularly robust over California, where it is only partially offset by projected decreases in low-medium intensity precipitation. Over the Mediterranean Basin, however, losses from decreasing frequency of low-medium-intensity precipitation are projected to dominate gains from intensifying projected extreme precipitation. MedClim regions are projected to become more sub-tropical, i.e. made dryer via pole-ward expanding subtropical subsidence. California’s more nuanced hydrological future reflects a precarious balance between the expanding subtropical high from the south and the south-eastward extending Aleutian low from the north-west. These dynamical mechanisms and thermodynamic moistening of the warming atmosphere result in increased horizontal water vapor transport, bolstering extreme precipitation events.

Precipitation in a warming world: Assessing projected hydro‐climate changes in California and other Mediterranean climate regions

Nature Portfolio (Springer Nature) | September 7th, 2017

In most Mediterranean climate (MedClim) regions around the world, global climate models (GCMs) consistently project drier futures. In California, however, proj

In most Mediterranean climate (MedClim) regions around the world, global climate models (GCMs) consistently project drier futures. In California, however, projections of changes in annual precipitation are inconsistent. Analysis of daily precipitation in 30 GCMs reveals patterns in projected hydrometeorology over each of the five MedClm regions globally and helps disentangle their causes. MedClim regions, except California, are expected to dry via decreased frequency of winter precipitation. Frequencies of extreme precipitation, however, are projected to increase over the two MedClim regions of the Northern Hemisphere where projected warming is strongest. The increase in heavy and extreme precipitation is particularly robust over California, where it is only partially offset by projected decreases in low-medium intensity precipitation. Over the Mediterranean Basin, however, losses from decreasing frequency of low-medium-intensity precipitation are projected to dominate gains from intensifying projected extreme precipitation. MedClim regions are projected to become more sub-tropical, i.e. made dryer via pole-ward expanding subtropical subsidence. California’s more nuanced hydrological future reflects a precarious balance between the expanding subtropical high from the south and the south-eastward extending Aleutian low from the north-west. These dynamical mechanisms and thermodynamic moistening of the warming atmosphere result in increased horizontal water vapor transport, bolstering extreme precipitation events.