North Lahontan

Climate-Altered Wetlands Challenge Waterbird Use and Migratory Connectivity in Arid Landscapes

Nature Portfolio (Springer Nature) | March 15th, 2019

Wetlands in arid landscapes provide critical habitat for millions of migratory waterbirds across the world and throughout their annual cycle. The scope and scale

Wetlands in arid landscapes provide critical habitat for millions of migratory waterbirds across the world and throughout their annual cycle. The scope and scale of understanding avian use of these wetlands in conjunction with changes in climate are daunting yet critical to address lest we lose continent-wide migratory pathways. Here, we assess changes in waterbird use of North America’s Pacific Flyway in the Great Basin by examining water availability and climate trends over the past 100 years. We found recent (1980–2015) climate warming has significantly reduced the amount and shifted seasonality of water flowing into wetlands. Further, we found remarkable changes in waterbird species composition over time. We propose that a reduced hydroperiod and lower water quality from reduction in water level and flow limits sites used by waterbirds. These factors reduce chick survivorship as they cannot metabolize saline water, which makes suitable freshwater conditions a limiting resource. Collectively, climate-induced changes in Great Basin wetlands suggest a major shift in freshwater ecosystems, resulting in degradation of a continental migratory route. This work illustrates the importance of examining multi-scale changes in critical regional resources to understand their impact across a hemispheric flyway and provides a model to examine other flyways.

Climate-driven disturbances amplify forest drought sensitivity

Nature Portfolio (Springer Nature) | June 7th, 2024

Climate-informed hydrologic modeling and policy typology to guide managed aquifer recharge

American Association for the Advancement of Science (AAAS) | April 21st, 2021

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deploy

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deployment of this multibeneficial adaptation option is fundamentally constrained by how much water is available for recharge (WAFR) at present and under future climate change. Here, we develop a climate-informed and policy-relevant framework to quantify WAFR, its uncertainty, and associated policy actions. Despite robust and widespread increases in future projected WAFR in our case study of California (for 56/80% of subbasins in 2070–2099 under RCP4.5/RCP8.5), strong nonlinear interactions between diversion infrastructure and policy uncertainties constrain how much WAFR can be captured. To tap future elevated recharge potential through infrastructure expansion under deep uncertainties, we outline a novel robustness-based policy typology to identify priority areas of investment needs. Our WAFR analysis can inform effective investment decisions to adapt to future climate-fueled drought and flood risk over depleted aquifers, in California and beyond.

Climate-Smart Tools to Protect California’s Freshwater Biodiversity

Public Policy Institute of California (PPIC) | May 28th, 2024

California’s freshwater ecosystems—and the native plants and animals that rely on them—have been in decline for decades. Roughly half of California’s native fresh

California’s freshwater ecosystems—and the native plants and animals that rely on them—have been in decline for decades. Roughly half of California’s native freshwater species are highly vulnerable to extinction within this century. But efforts to protect and recover native species now face an additional serious threat: climate change, which is accelerating and compounding the impacts of past and current land and water management issues. Simply working harder, using the same insufficient approaches to conservation, is unlikely to be successful. New approaches, including some that are experimental or highly controversial, are urgently needed. Although California has recently made important strides in setting goals for salmon, the state lacks a comprehensive approach to protecting native biodiversity in the face of climate change. We have identified a portfolio of actions that can help California rise to this urgent challenge.

Commercial, Industrial, and Institutional Task Force Water Use Best Management Practices Report to the Legislature

California Department of Water Resources (DWR) | October 21st, 2013

This report to Legislature, Commercial, Industrial, and Institutional Task Force Water Use Best Management Practices, identifies specific practices to improve water use e

This report to Legislature, Commercial, Industrial, and Institutional Task Force Water Use Best Management Practices, identifies specific practices to improve water use efficiency and support California’s water supply sustainability. It is intended to provide the CII sectors with information on water-saving technologies and BMPs applicable in the CII sectors. The report is also intended for use as a resource for: • Existing and new businesses, facilities, and institutions • Developers, consultants, and designers • Water service providers • Planning agencies • Policy makers This two-part document is linked below.  The Executive Summary is also linked in the display window. Executive Summary Volume 1 - A Summary Volume 2 - Technical Information

Community estimate of global glacier mass changes from 2000 to 2023

Nature Portfolio (Springer Nature) | February 19th, 2025

Glaciers are indicators of ongoing anthropogenic climate change1. Their melting leads to increased local geohazards2, and impacts marine3 and terrestrial4,5 ecosystems, r

Glaciers are indicators of ongoing anthropogenic climate change1. Their melting leads to increased local geohazards2, and impacts marine3 and terrestrial4,5 ecosystems, regional freshwater resources6, and both global water and energy cycles7,8. Together with the Greenland and Antarctic ice sheets, glaciers are essential drivers of present9,10 and future11,12,13 sea-level rise. Previous assessments of global glacier mass changes have been hampered by spatial and temporal limitations and the heterogeneity of existing data series14,15,16. Here we show in an intercomparison exercise that glaciers worldwide lost 273 ± 16 gigatonnes in mass annually from 2000 to 2023, with an increase of 36 ± 10% from the first (2000–2011) to the second (2012–2023) half of the period. Since 2000, glaciers have lost between 2% and 39% of their ice regionally and about 5% globally. Glacier mass loss is about 18% larger than the loss from the Greenland Ice Sheet and more than twice that from the Antarctic Ice Sheet17. Our results arise from a scientific community effort to collect, homogenize, combine and analyse glacier mass changes from in situ and remote-sensing observations. Although our estimates are in agreement with findings from previous assessments14,15,16 at a global scale, we found some large regional deviations owing to systematic differences among observation methods. Our results provide a refined baseline for better understanding observational differences and for calibrating model ensembles12,16,18, which will help to narrow projection uncertainty for the twenty-first century11,12,18. Click here for more about the Glacier Mass Balance Intercomparison Exercise 

Compounding effects of climate change and WUI expansion quadruple the likelihood of extreme-impact wildfires in California

Nature Portfolio (Springer Nature) | February 21st, 2025

Previous research has examined individual factors contributing to wildfire risk, but the compounding effects of these factors remain underexplored. Here, we introduce the

Previous research has examined individual factors contributing to wildfire risk, but the compounding effects of these factors remain underexplored. Here, we introduce the “Integrated Human-centric Wildfire Risk Index (IHWRI)” to quantify the compounding effects of fire-weather intensification and anthropogenic factors—including ignitions and human settlement into wildland—on wildfire risk. While climatic trends increased the frequency of high-risk fire-weather by 2.5-fold, the combination of this trend with wildland-urban interface expansion led to a 4.1-fold increase in the frequency of conditions conducive to extreme-impact wildfires from 1990 to 2022 across California. More than three-quarters of extreme-impact wildfires—defined as the top 20 largest, most destructive, or deadliest events on record—originated within 1 km from the wildland-urban interface. The deadliest and most destructive wildfires—90% of which were human-caused—primarily occurred in the fall, while the largest wildfires—56% of which were human-caused—mostly took place in the summer. By integrating human activity and climate change impacts, we provide a holistic understanding of human-centric wildfire risk, crucial for policy development.

Conjunctive Water Management Resource Management Strategy

California Department of Water Resources (DWR) | April 29th, 2024

Conjunctive water management, also referred to as conjunctive use, is broadly defined as the coordinated and planned use and management of the different sources of water

Conjunctive water management, also referred to as conjunctive use, is broadly defined as the coordinated and planned use and management of the different sources of water in time and space. It is usually focused on surface water and groundwater resources to maximize the availability and reliability of water supplies in a region to meet various management objectives. It is a holistic approach to water resource management that can increase available water for beneficial uses, allow water agencies greater flexibility in scheduling deliveries, and improve drought resiliency (California Department of Water Resources 2003).

Contributions of Climate Change and ENSO Variability to Future Precipitation Extremes Over California

American Geophysical Union (AGU) | June 14th, 2023

Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | October 31st, 2023