North Coast

The impacts of climate change on coastal groundwater

Nature Portfolio (Springer Nature) | January 11th, 2024

Coastal groundwater (CGW) is a critical water resource for many communities and can be a key part of coastal ecosystems. Owing to its location, CGW faces both terrestrial

Coastal groundwater (CGW) is a critical water resource for many communities and can be a key part of coastal ecosystems. Owing to its location, CGW faces both terrestrial and marine effects of climate change while simultaneously being impacted by anthropogenic activities. In this Review, we discuss the expected impacts of climate change on CGW and CGW-dependent ecosystems. Sea-level rise, coastal flooding increases and precipitation and aridity changes will drive alterations in the amount, chemistry and fluxes of CGW. Impacts could also arise from changes in storm and cyclone activity, land and ocean temperature rises, cryosphere melt, ocean chemistry and coastal erosion, but the overall effect is understudied. Human-induced stressors, such as groundwater extraction, will interact with climate change impacts to alter CGW at different temporal and spatial scales. CGW-associated ecosystems are expected to respond to changes in an ecosystem and site-specific manner — for example, some coastal temperate and tropical ecosystems might be more impacted by seawater intrusion owing to sea-level rise and coastal flooding, whereas others, such as coastal polar ecosystems, could be more affected by increases in cryosphere melt. A comprehensive and global CGW observatory programme is needed to better understand baseline CGW conditions, track change and support resource management.

The Importance of Interflow to Groundwater Recharge in a Snowmelt-Dominated Headwater Basin

American Geophysical Union (AGU) | May 23rd, 2019

Understanding the sensitivity of groundwater generation to climate in a mountain system is complicated by the tight coupling of snow dynamics to vegetation and topogr

Understanding the sensitivity of groundwater generation to climate in a mountain system is complicated by the tight coupling of snow dynamics to vegetation and topography. To address these feedbacks, we combine LiDAR-derived snow observations with an integrated hydrologic model to quantify spatially and temporally distributed water fluxes across varying climate conditions in a Colorado River headwater basin. Results indicate annual groundwater flow is an important and stable source of stream water. However, interflow decreases during drought as a function increased plant water use and the relative fraction of groundwater to streams increases. Seasonal snowmelt and vegetation water use regulate small recharge rates in the lower portions of the basin, but snowmelt transported via interflow from high mountain ridges toward convergent topographic zones define preferential recharge in the upper subalpine. Recharge in this zone appears decoupled from annual climate variability and resilient to drought. 

The Klamath River’s dams are being removed. Inside the effort to restore a scarred watershed

Los Angeles Times | March 24th, 2024

HORNBROOK, Calif. — Near the California-Oregon border, reservoirs that once submerged valleys have been drained, revealing a stark landscape that had been underwater fo

HORNBROOK, Calif. — Near the California-Oregon border, reservoirs that once submerged valleys have been drained, revealing a stark landscape that had been underwater for generations. A thick layer of muddy sediment covers the sloping ground, where workers have been scattering seeds and leaving meandering trails of footprints. In the cracked mud, seeds are sprouting and tiny green shoots are appearing. With water passing freely through tunnels in three dams, the Klamath River has returned to its ancient channel and is flowing unhindered for the first time in more than a century through miles of waterlogged lands.

The Magnitude of California's Water Challenges

UnIversity of California, Davis (UC Davis) | June 4th, 2024

California will see increasing water scarcity from climate change, the end of overdrafting groundwater and the Colorado River’s massive reservoirs, increased water dedi

California will see increasing water scarcity from climate change, the end of overdrafting groundwater and the Colorado River’s massive reservoirs, increased water dedications for environmental flows, and other factors, such as salination of aquifers and land subsidence reducing canal capacities. Total reduction in average water availability in the coming decades will likely range from 4.6 to 9 million acre-feet per year. For context, this is equivalent to the water use of 1 – 2.8 million acres of irrigated agriculture or most urban water use in California. Perhaps 20-30% of this loss will likely be addressed by ongoing water conservation and supply improvements, being planned and implemented, leaving a 3 – 7.2 million acre-feet/year likely net average difference between statewide water demands and availability.

The NOAA NCEI marine microplastics database

Nature Portfolio (Springer Nature) | October 20th, 2023

Microplastics (<5 mm) pollution is a growing problem affecting coastal communities, marine ecosystems, aquatic life, and human health. The widespread occurrence of m

Microplastics (<5 mm) pollution is a growing problem affecting coastal communities, marine ecosystems, aquatic life, and human health. The widespread occurrence of marine microplastics, and the need to curb its threats, require expansive, and continuous monitoring. While microplastic research has increased in recent years and generated significant volumes of data, there is a lack of a robust, open access, and long-term aggregation of this data. The National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI) now provides a global open access to marine microplastics data on an easily discoverable and accessible GIS web map and data portal. The objective of this data portal is to develop a repository where microplastics data are aggregated, archived, and served in a user friendly, consistent, and reliable manner. This work contributes to NCEI’s efforts towards data standardization, integration, harmonization, and interoperability among national and international collaborators for monitoring global marine microplastics. This paper describes the NOAA NCEI global marine microplastics database, its creation, quality control procedures, and future directions.

The Northern California 2018 Extreme Fire Season

American Meteorological Society (AMS) | February 19th, 2020

The fire season of 2018 was the most extreme on record in Northern California in terms of the number of fatalities (95), over 22,000 structures destroyed, and over 600,00

The fire season of 2018 was the most extreme on record in Northern California in terms of the number of fatalities (95), over 22,000 structures destroyed, and over 600,000 ha burned. The most deadly and destructive fire in California history, the Camp Fire, occurred in Butte County in the Sierra Nevada foothills in early November, and caused 85 fatalities and destroyed nearly 19,000 structures. The largest fire complex in state history, the Mendocino Complex, which included the Ranch fire, the largest single fire in state history, burned nearly 186,000 ha. It occurred in July and August, killing one firefighter. In western Shasta County nearly 138,000 ha burned from July through September in the Carr, Hirz, and Delta Fires. These fires caused multiple closures of Interstate 5 and exhibited some of the most extreme fire behavior ever observed in California. The Carr Fire caused eight fatalities, including two firefighters and two workers supporting firefighting efforts, burned over 1,100 homes in west Redding, caused the evacuation of one-third of the city, and produced an extreme fire vortex with an Enhanced Fujita scale rating between 136 to 165 mph, making it arguably the strongest tornado type event in state history, and one of the strongest documented cases in the world (Lareau et al. 2018).

The Pacific Decadal Oscillation modulated marine heatwaves in the Northeast Pacific during past decades

Nature Portfolio (Springer Nature) | June 19th, 2023

The potential of collaborative solutions to improve management of California (United States) wildlands

Restoration Ecology, Society for Ecological Restoration (SER) | November 13th, 2024

The Rainfall Intensity-Duration Control of Debris Flows After Wildfire

American Geophysical Union (AGU) | May 23rd, 2023

The Rebirth of California Fish & Game Code Section 5937: Water for Fish

University of California, Davis (UC Davis) | July 1st, 2012

Swarms of living creatures will live wherever the river flows. There will be large numbers of fish, because this water flows there and makes the salt water fresh; so wh

Swarms of living creatures will live wherever the river flows. There will be large numbers of fish, because this water flows there and makes the salt water fresh; so where the river flows everything will live. Fishermen will stand along the shore; from En Gedi to En Eglaim there will be places for spreading nets. In an average year, California receives inflows and imports of water totaling around 200 million acre-feet,2 enough water to cover the entire state twenty-three inches deep. But California is a state of spatial and temporal water extremes. Spatially, precipitation varies wildly: Death Valley in the Southeast averages less than three inches per year, yet the northwestern corner of the state averages over 140 inches per year. More than 70% of California’s stream flow originates north of Sacramento, but more than 80% of the water is used south of Sacramento. Temporally, precipitation varies both seasonally and annually. California’s wet season typically runs from October or November to April or May, with little or no precipitation during the growing season, from May to September.7 Annual rainfalls of 40% or more below average and 36% or more above average each typically occur once every six to seven years.  To balance these extremes, over 1,300 dams store water across the state, supplying water for urban, industrial, and agricultural uses. While these uses sustain a tremendous part of California’s economy, they also come at high, often unappreciated costs. Fish also need water, so dams that alter water flows for human benefits may also have marked negative impacts on fish.