More frequent atmospheric rivers slow the seasonal recovery of Arctic sea ice

Nature Portfolio (Springer Nature) | February 6th, 2023

In recent decades, Arctic sea-ice coverage underwent a drastic decline in winter, when sea ice is expected to recover following the melting season. It is unclear to what

In recent decades, Arctic sea-ice coverage underwent a drastic decline in winter, when sea ice is expected to recover following the melting season. It is unclear to what extent atmospheric processes such as atmospheric rivers (ARs), intense corridors of moisture transport, contribute to this reduced recovery of sea ice. Here, using observations and climate model simulations, we find a robust frequency increase in ARs in early winter over the Barents–Kara Seas and the central Arctic for 1979–2021. The moisture carried by more frequent ARs has intensified surface downward longwave radiation and rainfall, caused stronger melting of thin, fragile ice cover and slowed the seasonal recovery of sea ice, accounting for 34% of the sea-ice cover decline in the Barents–Kara Seas and central Arctic. A series of model ensemble experiments suggests that, in addition to a uniform AR increase in response to anthropogenic warming, tropical Pacific variability also contributes to the observed Arctic AR changes.

More state and local attention to financing can advance sustainable groundwater management

Berkeley Law Center for Law, Energy, & the Environment | April 12th, 2025

More with Less: Agricultural Water Conservation and Efficiency in California – A Special Focus on the Delta

Pacific Institute | September 8th, 2008

California farmers can grow more food and fiber with less water, according to the Pacific Institute report, More with Less: Agricultural Water Conservation and Efficiency

California farmers can grow more food and fiber with less water, according to the Pacific Institute report, More with Less: Agricultural Water Conservation and Efficiency in California – A Special Focus on the Delta. The report offers a comprehensive analysis of how to maintain a strong agricultural economy while improving the efficiency of water use and reducing groundwater overdraft and water withdrawals from the critically threatened Sacramento-San Joaquin Delta. The study finds agricultural water-use efficiency can be improved through careful planning, adopting existing, cost-effective technologies and management practices, and implementing feasible policy changes. The report also provides recommendations to overcome some of the financial, legal, and institutional barriers that can hinder farmers from implementing such adaptations and investments.

Mound Basin Groundwater Sustainability Plan

Mound Basin Groundwater Sustainability Agency | December 31st, 2021

The goal of this GSP is to sustainably manage the groundwater resources of the Mound Basin for the benefit of current and anticipated future beneficial users of groundwat

The goal of this GSP is to sustainably manage the groundwater resources of the Mound Basin for the benefit of current and anticipated future beneficial users of groundwater and the welfare of the general public who rely directly or indirectly on groundwater. This GSP describes the approach to achieve and maintain a sustainable groundwater resource free of undesirable results pursuant to the SGMA, while establishing long-term reliability no later than 20 years from GSP adoption through implementation. Due to size, this file has been divided into three parts. Part 1, Part 2, Part 3

Mountain Rivers

American Geophysical Union (AGU) | January 1st, 2000

Published by the American Geophysical Union as part of the Water Resources Monograph Series, Volume 14. I wrote this book in response to a need expressed by one of my

Published by the American Geophysical Union as part of the Water Resources Monograph Series, Volume 14. I wrote this book in response to a need expressed by one of my Ph.D. students, David Merritt, who walked into my office one afternoon for a summary reference on mountain rivers. Search as I might, I could not find such a reference in my files. I did find a stack of individual articles, however, and sent David on his way loaded up with them. As I thought about it, I realized that a summary reference on mountain rivers could be very useful, particularly given the increasing interest in the subject that I have noticed these last few years. Thus I began to write a review of the fluvial geomorphology of mountain rivers and, as such volumes will, this grew into a broader review of physical, biological, and chemical characteristics of mountain rivers, and of human interactions with these rivers.

Mountain Rivers Revisited

American Geophysical Union (AGU) | January 1st, 2010

Published by the American Geophysical Union as part of the Water Resources Monograph Series, Volume 19. What are the forms and processes characteristic of mountain riv

Published by the American Geophysical Union as part of the Water Resources Monograph Series, Volume 19. What are the forms and processes characteristic of mountain rivers and how do we know them? Mountain Rivers Revisited, an expanded and updated version of the earlier volume Mountain Rivers, answers these questions and more. Here is the only comprehensive synthesis of current knowledge about mountain rivers available. While continuing to focus on physical process and form in mountain rivers, the text also addresses the influences of tectonics, climate, and land use on rivers, as well as water chemistry, hyporheic exchange, and riparian and aquatic ecology. With its numerous illustrations and references, hydrologists, geomorphologists, civil and environmental engineers, ecologists, resource planners, and their students will find this book an essential resource.

Mountain rock glaciers contain globally significant water stores

Nature Portfolio (Springer Nature) | February 12th, 2018

Glacier- and snowpack-derived meltwaters are threatened by climate change. Features such as rock glaciers (RGs) are climatically more resilient than glaciers and

Glacier- and snowpack-derived meltwaters are threatened by climate change. Features such as rock glaciers (RGs) are climatically more resilient than glaciers and potentially contain hydrologically valuable ice volumes. However, while the distribution and hydrological significance of glaciers is well studied, RGs have received comparatively little attention. Here, we present the first near-global RG database (RGDB) through an analysis of current inventories and this contains >73,000 RGs. Using the RGDB, we identify key data-deficient regions as research priorities (e.g., Central Asia). We provide the first approximation of near-global RG water volume equivalent and this is 83.72 ± 16.74 Gt. Excluding the Antarctic and Subantarctic, Greenland Periphery, and regions lacking data, we estimate a near-global RG to glacier water volume equivalent ratio of 1:456. Significant RG water stores occur in arid and semi-arid regions (e.g., South Asia East, 1:57). These results represent a first-order approximation. Uncertainty in the water storage estimates includes errors within the RGDB, inherent flaws in the meta-analysis methodology, and RG thickness estimation. Here, only errors associated with the assumption of RG ice content are quantified and overall uncertainty is likely larger than that quantified. We suggest that RG water stores will become increasingly important under future climate warming.

Movement and Age of Ground Water in the Western Part of the Mojave Desert, Southern California, USA

U.S. Geological Survey (USGS) | July 15th, 2004

Tritium and carbon-14 data in water from wells in the Mojave River and the Morongo groundwater basins in the western part of the Mojave Desert show recent recharge focuse

Tritium and carbon-14 data in water from wells in the Mojave River and the Morongo groundwater basins in the western part of the Mojave Desert show recent recharge focused in the floodplain aquifer along the Mojave River. Older ground water was present in parts of the regional aquifer that surround and underlie the floodplain aquifer. Movement of water between the floodplain and the regional aquifers occurs near on the upgradient side of faults as water from the regional aquifer discharges to the floodplain aquifer and on the downgradient side of the faults where water from the floodplain aquifer recharges the regional aquifer. On the basis of carbon-14 ages, corrected for mineralogic reactions with aquifer materials, water from some wells was recharged more than 20,000 years ago. Geochemical data show ground-water recharge has gradually decreased as the climate changed since that time.

Movement of synthetic organic compounds in the food web after the introduction of invasive quagga mussels (Dreissena bugensis) in Lake Mead, Nevada and Arizona, USA

Publisher not available | August 21st, 2020

Introductions of dreissenid mussels in North America have been a significant concern over the last few decades. This study assessed the distribution of synthetic organic

Introductions of dreissenid mussels in North America have been a significant concern over the last few decades. This study assessed the distribution of synthetic organic compounds (SOCs) in the food web of Lake Mead, Nevada/Arizona, USA and how this distribution was influenced by the introduction of invasive quagga mussels. A clear spatial gradient of SOC concentrations in water was observed between lake basins downstream of populated areas and more rural areas. Within the food web, trophic magnification factors (TMF) indicated statistically significant biomagnification for nine, and biodilution for two, of 22 SOCs examined. The highest value recorded was for PCB 118 (TMF, 5.14), and biomagnification of methyl triclosan (TMF, 3.85) was also apparent. Biodilution was observed for Tonalide® (0.06) and Galaxolide® (0.38). Total SOC concentration in quagga mussels was higher than in three pelagic fishes. Also, 19 of 20 SOC examined in Largemouth Bass (Micropterus salmoides) had substantially lower concentrations in 2013, when quagga mussels had become well established, than in 2007/08, soon after quagga mussels were introduced. Estimates of SOC concentrations in the water column and quagga mussels suggest that a considerable portion (~10.5%) of the SOC mass in the lake has shifted from the pelagic to the benthic environments due to quagga mussel growth. These observations suggest that benthic species, such as the endangered Razorback Sucker, may be experiencing increased risk of SOC exposure. In addition, stable isotope analysis (carbon and nitrogen) indicated a decrease in the nutritional value of zooplankton to consumers (e.g., Razorback Sucker larvae) since quagga mussels became established. These changes could affect Razorback Sucker larval survival and recruitment. Results from this study strongly suggest that the introduction of quagga mussels has greatly altered the dynamics of SOCs and other processes in the food web of Lake Mead.

Moving Forward Effort: Phase 1 Report

U.S. Bureau of Reclamation (USBR) | May 1st, 2015

In 2012, the Bureau of Reclamation (Reclamation), in partnership with the seven Colorado River Basin States (Basin States) and in collaboration with a wide spectrum of

In 2012, the Bureau of Reclamation (Reclamation), in partnership with the seven Colorado River Basin States (Basin States) and in collaboration with a wide spectrum of Colorado River Basin (Basin) stakeholders, published the most comprehensive study of future Basin supply and demand ever undertaken. The Colorado River Basin Water Supply and Demand Study (Basin Study) confirmed that, in the absence of timely action, there are likely to be significant shortfalls between projected water supplies and demands in coming decades. The Basin Study also confirmed that a wide range of solutions are needed to mitigate and adapt to such shortfalls, which are likely to affect each sector (agricultural, municipal, energy, and environmental, for example) dependent on the Colorado River and its tributaries. In response to the findings of the Basin Study, in May 2013, Reclamation and the Basin States, in collaboration with the Ten Tribes Partnership and conservation organizations, initiated the Moving Forward effort to build on future considerations and next steps identified in the Basin Study. The Moving Forward effort builds upon and enhances the broad, inclusive stakeholder process demonstrated in the Basin Study with an ultimate goal of identifying actionable steps to address projected water supply and demand imbalances that have broad-based support and provide a wide-range of benefits. The Moving Forward effort is being conducted in a phased approach. Phase 1, which was funded by Reclamation and the Basin States, began with the formation of a Coordination Team and three multi-stakeholder workgroups that focus on water conservation, reuse, and environmental and recreational flows. The Phase 1 Report documents the activities and outcomes of the workgroups during this phase. Commenting on the information provided in the Phase 1 Report is encouraged. Written comments should be submitted within 90 days following the release of this report. The comments will be summarized and posted to the Moving Forward website and will be considered in future Moving Forward phases. Instructions for submitting comments are provided at [this link].