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2020 Water Resilience Portfolio (draft)

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2020 Water Resilience Portfolio (draft)
California Natural Resources Agency | January 2, 2020...
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A changing framework for urban water systems

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A changing framework for urban water systems
American Chemical Society (ACS) | May 8, 2013...
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Urban water infrastructure and the institutions responsible for its management have gradually evolved over the past two centuries. Today, they are under increasing...

Urban water infrastructure and the institutions responsible for its management have gradually evolved over the past two centuries. Today, they are under increasing stress as water scarcity and a growing recognition of the importance of factors other than the cost of service provision are forcing a reexamination of long-held ideas. Research and development that supports new technological approaches and more effective management strategies are needed to ensure that the emerging framework for urban water systems will meet future societal needs

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A freshwater conservation blueprint for California: prioritizing watersheds for freshwater biodiversity

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A freshwater conservation blueprint for California: prioritizing watersheds for freshwater biodiversity
Freshwater Science, University of Chicago Press Journals | April 18, 2018...
Summary
Conservation scientists have adapted conservation planning principles designed for protection of habi- tats ranging from terrestrial to freshwater ecosystems. We applied current approaches...

Conservation scientists have adapted conservation planning principles designed for protection of habi- tats ranging from terrestrial to freshwater ecosystems. We applied current approaches in conservation planning to prioritize California watersheds for management of biodiversity. For all watersheds, we compiled data on the pre- sence/absence of herpetofauna and fishes; observations of freshwater-dependent mammals, selected invertebrates, and plants; maps of freshwater habitat types; measures of habitat condition and vulnerability; and current manage- ment status. We analyzed species-distribution data to identify areas of high freshwater conservation value that op- timized representation of target taxa on the landscape and leveraged existing protected areas. The resulting priority network encompasses 34% of the area of California and includes ≥10% of the geographic range for all target taxa. High-value watersheds supported nontarget freshwater taxa and habitats, and focusing on target taxa may provide broad conservation value. Most of the priority conservation network occurs on public lands (69% by area), and 46% overlaps with protected areas already managed for biodiversity. A significant proportion of the network area is on private land and underscores the value of programs that incentivize landowners to manage freshwater species and habitats. The priority conservation areas encompass more freshwater habitats/ha than existing protected areas. Land use (agriculture and urbanization), altered fire regimes, nonnative fish communities, and flow impairment are the most important threats to freshwater habitat in the priority network, whereas factors associated with changing climate are the key drivers of habitat vulnerability. Our study is a guide to a comprehensive approach to freshwater conservation currently lacking in California. Conservation resources are often limited, so prioritiza- tion tools are valuable assets to land and water managers.

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A spatially comprehensive, hydrometeorological data set for Mexico, the U.S., and Southern Canada 1950–2013

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A spatially comprehensive, hydrometeorological data set for Mexico, the U.S., and Southern Canada 1950–2013
Nature | August 18, 2015...
Summary
A data set of observed daily precipitation, maximum and minimum temperature, gridded to a 1/16° (~6 km) resolution, is described that spans the...

A data set of observed daily precipitation, maximum and minimum temperature, gridded to a 1/16° (~6 km) resolution, is described that spans the entire country of Mexico, the conterminous U.S. (CONUS), and regions of Canada south of 53° N for the period 1950–2013. The dataset improves previous products in spatial extent, orographic precipitation adjustment over Mexico and parts of Canada, and reduction of transboundary discontinuities. The impacts of adjusting gridded precipitation for orographic effects are quantified by scaling precipitation to an elevation-aware 1981–2010 precipitation climatology in Mexico and Canada. Differences are evaluated in terms of total precipitation as well as by hydrologic quantities simulated with a land surface model. Overall, orographic correction impacts total precipitation by up to 50% in mountainous regions outside CONUS. Hydrologic fluxes show sensitivities of similar magnitude, with discharge more sensitive than evapotranspiration and soil moisture. Because of the consistent gridding methodology, the current product reduces transboundary discontinuities as compared with a commonly used reanalysis product, making it suitable for estimating large-scale hydrometeorologic phenomena.

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A tale of two California droughts: Lessons amidst record warmth and dryness in a region of complex physical and human geography

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A tale of two California droughts: Lessons amidst record warmth and dryness in a region of complex physical and human geography
American Geophysical Union (AGU) | November 19, 2015...
Summary
The state of California has experienced the worst drought in its historical record during 2012–2015. Adverse effects of this multi year event have been...
The state of California has experienced the worst drought in its historical record during 2012–2015. Adverse effects of this multi year event have been far from uniformly distributed across the region, ranging from remarkably mild in most of California’s densely populated coastal cities to very severe in more rural, agricultural, and wildfire-prone regions. This duality of impacts has created a tale of two very different California droughts—highlighting enhanced susceptibility to climate stresses at the environmental andsocioeconomic margins of California. From a geophysical perspective, the persistence of related atmospheric anomalies has raised a number of questions regarding the drought’s origins—including the role of anthropogenic climate change. Recent investigations underscore the importance of understanding the underlying physical causes of extremes in the climate system, and the present California drought represents an excellent case study for such endeavors. Meanwhile, a powerful El Niño event in the Pacific Ocean offers the simultaneous prospect of partial drought relief but also an increased risk of flooding during the 2015–2016 winter—a situation illustrative of the complex hydroclimatic risks California and other regions are likely to face in a warming world.

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Accounting for Climate Change
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Accounting for Climate Change
Department of Water Resources | April 29, 2010...
Summary
In recent years, evidence that global climate will have significant effects on water resources in California has continued to accumulate. Climate change can...
In recent years, evidence that global climate will have significant effects on water resources in California has continued to accumulate. Climate change can affect the amount, timing, and form of precipitation, whether rain or snow, that California receives, as well as the sea level of the Pacific Ocean. Moreover, changes in weather, especially temperature, and atmospheric composition can affect water use and consumption. Changes in climate have occurred during the 20th century, with noticeable warming in the last two decades.

Most scientists feel that changes during the last several decades are likely mostly due to human activities, but natural causes and variability cannot be ruled out as a significant component. Likewise, projections of amount of warming and other climate changes during the 21st century are wide ranging, depending on assumptions and models.

A major cause of expected climate change is the increasing amounts of greenhouse gases, such as carbon dioxide, in the atmosphere as a result of man’s activities. These gases, as well as water vapor, allow solar radiation to pass inward through the atmosphere, but trap the longer wave infrared radiation reflected back from the earth’s surface. Greenhouse gases are accumulating in the atmosphere; the following chart shows the gradual build up in carbon dioxide at Mauna Loa in Hawaii, as measured by Scripps Institution of Oceanography scientists. The annual cycle is caused by northern hemisphere vegetation uptake during the growing season. Other significant greenhouse gases are methane, nitrous oxide, halocarbons (like freon and its replacements), and, of course, water vapor itself. Cloud cover is an important element in the global radiation balance.

Whatever the causes, the prospects of significant changes warrant examination of how the State’s water infrastructure and natural systems can accommodate or adapt to climate changes and whether more needs to be done to detect, evaluate and respond to water resource system effects. Many uncertainties remain, primarily on the degree of change to be expected. Responsible planning requires that the California water planning community work with climate scientists and others to reduce these uncertainties and to begin to prepare for those impacts that are well understood, already appearing as trends, or likely to appear. In this section we review possible impacts and address some of the responses appropriate for water planners and managers.

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Adaptability and adaptations of California’s water supply system to dry climate warming

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Adaptability and adaptations of California’s water supply system to dry climate warming
Climactic Change, Springer | November 27, 2007...
Summary
Economically optimal operational changes and adaptations for California’s water supply system are examined for a dry form of climate warming (GFDL CM2.1 A2)...
Economically optimal operational changes and adaptations for California’s water supply system are examined for a dry form of climate warming (GFDL CM2.1 A2) with year 2050 water demands and land use. Economically adaptive water management for this climate scenario is compared to a similar scenario with the historical climate. The effects of population growth and land use alone are developed for comparison. Compared with the historic hydrology, optimized operations for the dry climate warming scenario raise water scarcity and total operation costs by $490 million/year with year 2050 demands. Actual costs might be somewhat higher where non-economic objectives prevail in water management. The paper examines the economical mix of adaptation, technologies, policies, and operational changes available to keep water supply impacts to such modest levels. Results from this screening model suggest promising alternatives and likely responses and impacts. Optimized operations of ground and surface water storage change significantly with climate. Dry-warm climate change increases the seasonal storage range of surface reservoirs and aquifers. Surface reservoir peak storage usually occurs about a month earlier under dry-warm climate change.

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Adaptation Strategies for Agricultural Sustainability in Yolo County, California
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Adaptation Strategies for Agricultural Sustainability in Yolo County, California
California Energy Commission (CEC) | July 31, 2012...
Summary
This place-based case study in an agricultural county in California’s Central Valley focused on the period of 2010–2050, and dealt with biophysical and...
This place-based case study in an agricultural county in California’s Central Valley focused on the period of 2010–2050, and dealt with biophysical and socioeconomic issues related to both mitigation of greenhouse gas (GHG) emissions and to adaptation to an uncertain climate. In the past 100 years, changes in crop acreage has been more related to crop price and availability of irrigation water than to growing degree days during summer, and in fact, summer temperatures have increased less than winter temperatures. Econometric analysis indicated that warmer winters, as projected by Geophysical Fluid Dynamics Laboratory-Bias Corrected Constructed Analog during 2035–2050, could result in less wheat acreage, more alfalfa and tomato acreage, and slight effects on tree and vine crops. The Water Evaluation and Planning (WEAP) model showed that these econometric projections did not reduce irrigation demand under either the B1 or A2 scenarios, but a diverse, water-efficient cropping pattern combined with improved irrigation technology reduced demand to 12 percent below the historic mean.

Collaboration during development of Yolo County’s Climate Action Plan showed that nitrous oxide (mainly from nitrogen fertilizers) was the main source (40 percent) of agricultural emissions. Emissions from cropland and rangeland were several orders of magnitude lower than urbanized land per unit area. A survey distributed to 570 farmers and ranchers achieved a 34 percent response rate. Farmers concerned about climate change were more likely to implement water conservation practices, and adopt voluntary GHG mitigation practices.

Use of the urban growth model (UPlan) showed that channeling much or all future urban development into existing urban areas will increase ecosystem services by preserving agricultural land and open space, immensely reducing the Yolo County’s GHG emissions, and greatly enhancing agricultural sustainability.

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Adapting California’s Water Management to Climate Change
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Adapting California’s Water Management to Climate Change
Public Policy Institute of California (PPIC) | January 12, 2009...
Summary
Among the potential impacts of climate change, accelerated sea level rise and a reduced Sierra snowpack are the most certain. Both will pose...
Among the potential impacts of climate change, accelerated sea level rise and a reduced Sierra snowpack are the most certain. Both will pose significant challenges for water supply and flood management. Water utilities have already begun to plan for these changes, but flood control agencies are lagging behind and face greater regulatory constraints. State leadership is needed to resolve some threats, including the risk of catastrophic failure in the Sacramento-San Joaquin Delta. This report was prepared as part of the Preparing California for a Changing Climate project.

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Adapting to Climate Change and Drought in Selected California Groundwater Basins: Local Achievements and Challenges

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Adapting to Climate Change and Drought in Selected California Groundwater Basins: Local Achievements and Challenges
California Natural Resources Agency | August 27, 2018...
Summary
Climate change projections are for higher temperatures and extreme droughts by the end of the 21st century. This will alter the natural recharge...
Climate change projections are for higher temperatures and extreme droughts by the end of the 21st century. This will alter the natural recharge of groundwater, including decreased inflow from runoff, increased evaporative losses, and warmer and shorter winter seasons, impacts that are likely to exacerbate already existing groundwater overdraft in many basins. Additionally, the imported surface water that can be delivered from the Central Valley Project (CVP) and State Water Project (SWP) to areas reliant on this water for groundwater recharge and consumptive use is projected to be less reliable and more expensive. Yet groundwater is a critical water supply source during drought when it compensates for reduced surface water supplies. The need for proactive adaptation strategies to address the extreme droughts projected under climate change are frequently discussed, yet there are limited examples of such groundwater management strategies. This paper therefore explores:

1) How groundwater management agencies are planning for drought

2) What new approaches are currently being used that show promise for addressing the more extreme droughts projected under climate change?

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2020 Water Resilience Portfolio (draft)

2020 Water Resilience Portfolio (draft)

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A changing framework for urban water systems

A changing framework for urban water systems

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A freshwater conservation blueprint for California: prioritizing watersheds for freshwater biodiversity

A freshwater conservation blueprint for California: prioritizing watersheds for freshwater biodiversity

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A spatially comprehensive, hydrometeorological data set for Mexico, the U.S., and Southern Canada 1950–2013

A spatially comprehensive, hydrometeorological data set for Mexico, the U.S., and Southern Canada 1950–2013

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A tale of two California droughts: Lessons amidst record warmth and dryness in a region of complex physical and human geography

A tale of two California droughts: Lessons amidst record warmth and dryness in a region of complex physical and human geography

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Accounting for Climate Change

Accounting for Climate Change

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Adaptability and adaptations of California’s water supply system to dry climate warming

Adaptability and adaptations of California’s water supply system to dry climate warming

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Adaptation Strategies for Agricultural Sustainability in Yolo County, California

Adaptation Strategies for Agricultural Sustainability in Yolo County, California

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Adapting California’s Water Management to Climate Change

Adapting California’s Water Management to Climate Change

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Adapting to Climate Change and Drought in Selected California Groundwater Basins: Local Achievements and Challenges

Adapting to Climate Change and Drought in Selected California Groundwater Basins: Local Achievements and Challenges

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