Northern and Central Delta-Mendota Regions Revised Groundwater Sustainability Plan

San Luis & Delta-Mendota Water Authority (SLDMWA) | June 24th, 2022

Within the Delta-Mendota Subbasin, six (6) GSPs have been developed in a coordinated fashion with the goal of achieving sustainability for the Subbasin as a whole. The GS

Within the Delta-Mendota Subbasin, six (6) GSPs have been developed in a coordinated fashion with the goal of achieving sustainability for the Subbasin as a whole. The GSP Groups preparing the coordinated GSPs include: the Aliso Water District GSP Group, Farmers Water District GSP Group, Fresno County GSP Group, Grassland GSP Group, Northern & Central Delta-Mendota Region GSP Group, and San Joaquin River Exchange Contractors GSP Group. This GSP has been developed for the Northern and Central Delta-Mendota Regions, which are comprised of the following eight Groundwater Sustainability Agencies (GSAs): Central Delta-Mendota, City of Patterson, DM-II, Northwestern Delta-Mendota, Oro Loma Water District, Patterson Irrigation District, West Stanislaus Irrigation District, and Widren Water District. The Northern & Central Delta-Mendota Region GSP has been developed by these GSAs to meet SGMA regulatory requirements while reflecting local needs and preserving local control over water resources. This GSP provides a path to achieve and document sustainable groundwater management within 20 years following adoption, promoting the long-term sustainability of locally-managed groundwater resources now and into the future. Due to size, this file has been divided. Part 1, Part 2, Part 3

Ocean submesoscale fronts induce diabatic heating and convective precipitation within storms

Nature Portfolio (Springer Nature) | January 30th, 2025

The intensity of atmospheric storms is influenced by ocean temperature contrasts. While mesoscale sea surface temperature anomalies ( ~ 200 km-size) are known to inte

The intensity of atmospheric storms is influenced by ocean temperature contrasts. While mesoscale sea surface temperature anomalies ( ~ 200 km-size) are known to intensify storms via latent heat release, the role of finer oceanic scales remains unknown. Using a global coupled ocean-atmosphere simulation at a km-scale resolution, we show that half of latent heat flux variability is driven by oceanic motions at the meso- ( ~ 40%) and submesoscale ( ~ 10-20 km-size,  < 10%) in the Kuroshio Extension during winter. Additionally, ocean submesoscale fronts, with temperature gradients of 5 °C per 10 km, induce a secondary circulation reaching 4 km within the troposphere, which enhances diabatic processes and convective precipitations within storms. In the warm sector of storms, ocean submesoscale fronts locally account for half the total precipitations, averaging 14 mm day−1 over five days. As such, ocean submesoscale fronts pump moisture from the ocean to the atmosphere and have the potential to affect storm intensification.

On the Connection Between Global Hydrologic Sensitivity and Regional Wet Extremes

American Geophysical Union (AGU) | October 23rd, 2018

The global water cycle is expected to intensify under climate change and can be generally characterized by greater rainfall and surface evaporation in the future. However

The global water cycle is expected to intensify under climate change and can be generally characterized by greater rainfall and surface evaporation in the future. However, the rate at which the globally averaged precipitation increases is highly variable among different climate models. In this paper, we relate the intermodel variability in global water cycle intensification to differences in model projections of heavy precipitation in tropical and some extratropical regions. We also find that models consistently experience a trade‐off between increasing heavy and decreasing light‐moderate precipitation: Models with larger future increases in heavy precipitation exhibit greater compensating declines in light‐moderate rainfall. Differences in heavy precipitation changes are also tied to model resolution. Our study helps to provide new insight on the factors shaping projections of future precipitation extremes, which have strong implications for water resources, natural hazard risks associated with flooding, and ecosystem stability.

On the dynamics of the Hadley circulation and subtropical drying

Climate Dynamics (Springer) | April 10th, 2014

Changes in subtropical precipitation and the Hadley circulation (HC) are inextricably linked. The original Halley–Hadley model cannot explain certain aspects of the Ear

Changes in subtropical precipitation and the Hadley circulation (HC) are inextricably linked. The original Halley–Hadley model cannot explain certain aspects of the Earth’s meridional circulation in the tropics and is of limited use in understanding regional changes in precipitation. Here, we expand on previous work on the regional and seasonal aspects of the HC, in particular how land–sea temperature contrasts contribute to the strength and width of the HC. We show that the Earth’s HC is well described by three regionally distinct cells along the eastern edges of the major ocean basins with opposite circulations elsewhere. Moreover, comparable summertime hemisphere cells emerge in each region. While it has been recognized that continents modify the meridional pressure gradient, we demonstrate that a substantial part of the Earth’s HC is driven by zonal pressure gradients (ZPGs) that only exist due to continental heating and air–sea interaction. Projected changes in land–sea temperature contrasts in a warming climate due to the relatively low thermal capacity of land will also affect ZPGs and thus HC strength and width, with implications for extremes in hydroclimate and freshwater resources across the increasingly vulnerable subtropics.

On the Sources of Water Supply Forecast Error in Western Colorado

American Meteorological Society (AMS) | December 1st, 2023

One Water LA 2040 Plan

City of Los Angeles | April 30th, 2018

The purpose of the One Water LA 2040 Plan (Plan) is to increase sustainable water management for the City of Los Angeles (City). The City launched One Water LA with two p

The purpose of the One Water LA 2040 Plan (Plan) is to increase sustainable water management for the City of Los Angeles (City). The City launched One Water LA with two primary goals: 1. Develop a vision and implementation strategy to more sustainably and cost-effectively manage water. 2. Identify ways for City departments and regional agencies to integrate their water management strategies. Los Angeles Sanitation (LASAN) and the Los Angeles Department of Water and Power (LADWP) led the Plan's development, partnering with other City departments, regional agencies, academia, the business community, and other stakeholders. The Plan provides a comprehensive strategy for managing water in a more integrated, collaborative, and sustainable way through new project, program, and policy opportunities. The Implementation Strategy provides a roadmap to make the One Water LA Vision a reality. Additional water projects, programs, or policies that are the sole responsibility of one agency, including LADWP's aqueduct or groundwater remediation project, are contained in each agency's appropriate plans. This plan is divided into an Executive Summary and ten sections. Executive Summary Volume One: Summary Report Volume Two: Wastewater Facilities Plan Volume Three: Stormwater and Urban Runoff Facilities Plan Volume Four: Los Angeles River Flow Study Volume Five: Integration Opportunities Analysis Volume Six: Climate Risk and Resilience Assessment for Wastewater and Stormwater Infrastructure Volume Seven: Implementation Strategy Supporting Documents Volume Eight: Technical Support Materials Volume Nine: Stakeholder Engagement Materials, Part 1, Part 2, Part 3 Volume Ten: Programmatic Environmental Impact Report (in progress)

Order Approving Temporary Urgency Changes to Water Right License and Permit Terms Relating to Delta Water Quality Objectives

California State Water Resources Control Board (SWRCB) | February 21st, 2023

Origins of Extreme Climate States during the 1982–83 ENSO Winter

American Meteorological Society (AMS) | November 1st, 1997

Orographic amplification of El Niño teleconnections on winter precipitation across the Intermountain West of North America

Nature Portfolio (Springer Nature) | December 4th, 2023

Pacific sea-surface temperature related to rain in California

Nature Portfolio (Springer Nature) | October 1st, 1977

California is experiencing the worst drought in modern history, and there is much concern and speculation about future rainfall prospects. We recently succeeded in relati

California is experiencing the worst drought in modern history, and there is much concern and speculation about future rainfall prospects. We recently succeeded in relating South Atlantic sea surface temperatures (SST) to rain in northeastern Brazil1, and here we use similar methods to relate sea surface temperatures over the North Pacific Ocean to rainfall in California. We found December SST in the north-east Pacific off Washington to have a limited but definite predictive value, and to account for about 45% of the variation in California rainfall for the period February–April.