Developing Adaptation Strategies for San Luis Obispo: Preliminary Climate Change Vulnerability Assessment for Social Systems

California Energy Commission (CEC) | July 31st, 2012

San Luis Obispo faces a variety of risks from climate change, including extreme heat, a generally drier climate, increases in extreme weather events, and sea-level rise.

San Luis Obispo faces a variety of risks from climate change, including extreme heat, a generally drier climate, increases in extreme weather events, and sea-level rise. Important vulnerabilities are apparent for water supplies, in agriculture (especially for wine and cattle ranchers) and related tourism, for fishing, coastal tourism, coastal development and infrastructure, and for community services. Certain county populations may face disproportionate risks including the elderly, those already affected by diseases, and outdoor and migrant workers from extreme heat, people living in coastal and inland floodplains, those living at the wildland-urban interface, the student population, institutionalized individuals (especially the state hospital), and those members of the community that tend to be somewhat disenfranchised from public decision-making, such as non-English speaking individuals and those who can’t afford to take off from work to attend public meetings. The county is wise to begin planning and building its adaptive capacity at this time before climate change impacts become more severe, and before there may be greater competition for state and federal financial support for adaptation planning and implementation.

Developing the Next Framework to Manage the Colorado River: Flexible Tools to Benefit Tribes and the Basin

Water and Tribes Initiative | August 2nd, 2022

Development of a Mono Lake Water Level Model and Projections across the 21st Century

University of California, Los Angeles (UCLA) | March 17th, 2026

The UCLA Mono Lake Model (UCLA-MLM) was developed to assess how climate-driven changes and existing and alternative export criteria influence Mono Lake’s water level th

The UCLA Mono Lake Model (UCLA-MLM) was developed to assess how climate-driven changes and existing and alternative export criteria influence Mono Lake’s water level throughout the 21st century.

Development of Stage-Frequency Curves in the Sacramento-San Joaquin Delta for Climate Change and Sea Level Rise

California Energy Commission (CEC) | August 27th, 2018

Future changes in hydrologic patterns and sea level rise will impact water levels in the Sacramento-San Joaquin Delta (Delta), the hub of California’s water supply sys

Future changes in hydrologic patterns and sea level rise will impact water levels in the Sacramento-San Joaquin Delta (Delta), the hub of California’s water supply system and an important ecosystem and agricultural area. An important tool for flood management is stage frequency curves which indicate how often certain water levels (or stage) occur. The Delta poses inherent complexity in the determination of stage-frequency and requires a number of considerations. One needs to account for river flows coming into the Delta, as well as the effect of tides from the Delta’s connection to the ocean through San Francisco Bay. During storms, Delta water levels are also affected by storm surge from the advancing storm fronts coming from the Pacific Ocean. Under climate change, Delta water levels will also be affected by rising sea levels and expected changes in hydrology, such as shifts in timing and amount of precipitation and runoff and changes in how much of our precipitation falls as rain or snow (referred to as climate change hydrology in this paper). With these taken into consideration, this study lays out the assumption and method used to develop stage-frequency curves in the Delta for three different conditions: current hydrology conditions, current hydrology with sea level rise, and late-century climate change hydrology with sea level rise. In addition, water surface elevation profiles along the Sacramento and San Joaquin rivers for various magnitudes of flood events were compared to the top of levee elevations. Both the stage-frequency curves and the water surface elevation profiles comparisons to top of levee elevations provide valuable information to water resources planners and were applied to inform life and flood risk analysis for the Delta in the Central Valley Flood Protection Plan 2017 Update.

Dimension reduction approach for understanding resource-flow resilience to climate change

Nature Portfolio (Springer Nature) | June 15th, 2024

Disappearing Arctic sea ice reduces available water in the American west

American Geophysical Union (AGU) | March 24th, 2004

Recent decreases in Arctic sea ice cover and the probability of continued decreases have raised the question of how reduced Arctic sea ice cover will influence extrapo

Recent decreases in Arctic sea ice cover and the probability of continued decreases have raised the question of how reduced Arctic sea ice cover will influence extrapolar climate. Using a fully coupled earth system model, we generate one possible future Arctic sea ice distribution. We use this ‘‘future’’ sea ice distribution and the corresponding sea surface temperatures (SSTs) to run a fixed SST and ice concentration experiment with the goal of determining direct climate responses to the reduction in Arctic sea ice that is projected to occur in the next 50 years. Our results indicate that future reductions in Arctic sea ice cover could significantly reduce available water in the American west and highlight the fact that the most severe impacts of future climate change will likely be at a regional scale.

Disparities in urban vegetation degradation and heat exposure during drought periods in U.S. cities

nature Portfolio (Springer Nature) | December 15th, 2025

Policymakers are increasingly recognizing the necessity for the equitable distribution of urban green spaces across sociodemographic groups. Nevertheless, the extant rese

Policymakers are increasingly recognizing the necessity for the equitable distribution of urban green spaces across sociodemographic groups. Nevertheless, the extant research consistently highlights disparities in this allocation, frequently neglecting the critical implications of extreme droughts on vegetation-related inequalities. Leveraging satellite observations in conjunction with census data, we examine the drought-related disparities in urban vegetation degradation (UVD) and the corresponding heat exposure across sociodemographic groups within major U.S. cities. Our findings reveal that marginalized communities experience more severe UVD during droughts, a trend particularly pronounced in Sunbelt U.S. cities, such as those in Southern California and Texas. Additionally, the unequal UVD during drought exacerbates existing inequalities in heat exposure. These results highlight the urgent need for the implementation of targeted policies, including effective water supply management strategies. Such measures could mitigate thermal environmental injustices and promote equitable vegetation distribution under a warming climate.

Distribution of Landfalling Atmospheric Rivers on the U.S. West Coast During Water Year 2018 Through April

Scripps Institution of Oceanography at U.C. San Diego | March 1st, 2018

Forty-four atmospheric rivers (ARs) made landfall on the West Coast during the 2018 water year through April compared to 68 the year before, report meteorologists Chad H

Forty-four atmospheric rivers (ARs) made landfall on the West Coast during the 2018 water year through April compared to 68 the year before, report meteorologists Chad Hecht and Marty Ralph from the Center for Western Weather and Water Extremes, Scripps Institution of Oceanography at U.C. San Diego. This notes the ARs' landfall patterns, strength, geographic distribution, and timing.

Divergent effects of climate change on future groundwater availability in key mid-latitude aquifers

Nature Portfolio (Springer Nature) | July 24th, 2020

Groundwater provides critical freshwater supply, particularly in dry regions where surface water availability is limited. Climate change impacts on GWS (groundwater stora

Groundwater provides critical freshwater supply, particularly in dry regions where surface water availability is limited. Climate change impacts on GWS (groundwater storage) could affect the sustainability of freshwater resources. Here, we used a fully-coupled climate model to investigate GWS changes over seven critical aquifers identified as significantly distressed by satellite observations. We assessed the potential climate-driven impacts on GWS changes throughout the 21st century under the business-as-usual scenario (RCP8.5). Results show that the climate-driven impacts on GWS changes do not necessarily reflect the long-term trend in precipitation; instead, the trend may result from enhancement of evapotranspiration, and reduction in snowmelt, which collectively lead to divergent responses of GWS changes across different aquifers. Finally, we compare the climate-driven and anthropogenic pumping impacts. The reduction in GWS is mainly due to the combined impacts of over-pumping and climate effects; however, the contribution of pumping could easily far exceed the natural replenishment.

Downscaling global ocean climate models improves estimates of exposure regimes in coastal environments

Nature Portfolio (Springer Nature) | August 26th, 2020

Climate change is expected to warm, deoxygenate, and acidify ocean waters. Global climate models (GCMs) predict future conditions at large spatial scales, and these pred

Climate change is expected to warm, deoxygenate, and acidify ocean waters. Global climate models (GCMs) predict future conditions at large spatial scales, and these predictions are then often used to parameterize laboratory experiments designed to assess biological and ecological responses to future change. However, nearshore ecosystems are affected by a range of physical processes such as tides, local winds, and surface and internal waves, causing local variability in conditions that often exceeds global climate models. Predictions of future climatic conditions at local scales, the most relevant to ecological responses, are largely lacking. To fill this critical gap, we developed a 2D implementation of the Regional Ocean Modeling System (ROMS) to downscale global climate predictions across all Representative Concentration Pathway (RCP) scenarios to smaller spatial scales, in this case the scale of a temperate reef in the northeastern Pacific. To assess the potential biological impacts of local climate variability, we then used the results from different climate scenarios to estimate how climate change may affect the survival, growth, and fertilization of a representative marine benthic invertebrate, the red abalone Haliotis rufescens, to a highly varying multi-stressor environment. We found that high frequency variability in temperature, dissolved oxygen (DO), and pH increases as pCO2 increases in the atmosphere. Extreme temperature and pH conditions are generally not expected until RCP 4.5 or greater, while frequent exposure to low DO is already occurring. In the nearshore environment simulation, strong RCP scenarios can affect red abalone growth as well as reduce fertilization during extreme conditions when compared to global scale simulations.