Examining the Contribution of the Observed Global Warming Trend to the California Droughts of 2012/13 and 2013/14

American Meteorological Society (AMS) | September 30th, 2014

In this study, we examine the November–February California droughts of 2012/13 and 2013/14. During 2013/14, California had its warmest and third driest rainy se

In this study, we examine the November–February California droughts of 2012/13 and 2013/14. During 2013/14, California had its warmest and third driest rainy season on record (1895–2014), while the 2012/13 season registered as the 45th warmest and 38th driest (Vose et al. 2014). The 2013 January–December calendar year was the driest on record (Water CA 2014). These consecutive below-normal seasons conspired with warm temperatures to reduce California’s snowpack to the second lowest level since 1960, when recording began, with snowpack at 24% of normal (Water CA 2014). Between January 2013 and January 2014, satellite observations documented dramatic snowpack-related land cover change (NASA Earth Observatory 2014): in 2014, the Cascade, Sierra Nevada, and Coastal ranges were almost completely devoid of snow. In February and March of 2014, air temperatures were extremely warm (NOAA NCDC 2014; HPRC 2014), and U.S. Geological Survey (USGS) observations indicated extreme or moderate hydrologic drought (USGS 2014) and high levels of vegetation stress (VegDRI 2014). The state declared a drought emergency (NIDIS 2014). While it is too soon to assess the full impact of the 2012/13 and 2013/14 California droughts, they seem likely to substantially impact the state’s ability to generate hydrologic power, support agriculture, reduce the risk of forest and bush fires, and protect fragile ecosystems (Huffington Post 2014). *Chapter 4, Explaining Extreme Events of 2013 from a Climate Perspective, Bull. Amer. Meteor. Soc., 95 (9)

Excavation and Embankment by Water Power

Scientific American | July 24th, 1886

I wish to call the attention of the Society to a plan by which large excavations and embankments can be cheaply made —which is especially applicable to earthen dams

I wish to call the attention of the Society to a plan by which large excavations and embankments can be cheaply made —which is especially applicable to earthen dams— by simply applying the method used in the hydraulic mines that have been so largely developed in California. The system, in brief, is discharging the water under a vertical head of from 100 to 300 feet against the bank to be excavated. The momentum of the water cuts the bank, the material of which is conveyed by it into the flume, and thence by it to the place at which it is to be discharged. This point of discharge is generally in some water course or river, which soon becomes dammed by a perfectly water-tight dam, which remains intact and tight until it is destroyed, or partially so, by the winter's flood washing away the material from the top.

Executive Order N-10-19

State of California | April 29th, 2019

Executive Order N-4-23

State of California | March 10th, 2023

Executive Order N-7-23

State of California | May 17th, 2023

Executive Summary: An Evaluation of Compensatory Mitigation Projects Permitted Under Clean Water Act Section 401 by the California State Water Resources Control Board, 1991-2002

California State Water Resources Control Board (SWRCB) | August 1st, 2007

The purpose of this project, which was funded by the California State Water Resources Control Board (SWRCB), was to evaluate the compliance and wetland conditio

The purpose of this project, which was funded by the California State Water Resources Control Board (SWRCB), was to evaluate the compliance and wetland condition of compensatory wetland mitigation projects associated with Clean Water Act Section 401 Water Quality Certifications throughout California. This was done by selecting, reviewing and performing field evaluations for 143 permit files distributed across the 12 Water Board regions and sub-regions of the State. For each permit file we assessed the extent to which permittees complied with their mitigation conditions, including acreage requirements, whether the corresponding mitigation efforts resulted in optimal wetland condition, and if the habitat acreages gained through compensatory mitigation adequately replaced those lost through the permitted impacts. We found that permittees are largely following their permit conditions (although one-quarter to one-third of the time these are not met), but the resulting compensatory mitigation projects seldom result in wetlands with optimal condition.

Existing Accessible Modeling Tools Offer Limited Support to Evaluation of Impact Investment in Rangeland Ecosystem Services

Frontiers in Sustainable Food Systems (Frontiers) | September 24th, 2019

Privately owned rangelands in the western US support many ecosystem services and are threatened by financial incentives favoring conversion to housing development and m

Privately owned rangelands in the western US support many ecosystem services and are threatened by financial incentives favoring conversion to housing development and more intensive forms of agriculture. Recognizing this threat, the impact investment community has identified rangeland management as a potential investing strategy to produce financial returns while preserving or enhancing the ecosystem services provided by intact rangelands. This strategy is based primarily on the notion that a capital-intensive conversion from continuous to rotational grazing can financially sustain rangelands through a combination of increased productivity and potentially monetized ecosystem service flows. The potential for these gains is supported by compelling anecdotal evidence, yet a robust body of scientific literature based on rigorous field experiments has not supported those claims, nor produced transferrable estimates of the benefits provided by rotational grazing of livestock (particularly cattle in the western US). Therefore, to demonstrate investment viability and measure investment success, impact investors will likely need to address these well-documented disconnects through some combination of monitoring and process-based modeling. This study examines the extent to which existing modeling tools are up to this task, by assessing the ability of two process-based models to represent four specific rotational grazing benefits put forth by impact investors, using a ranch in northeastern Wyoming as a case study. Using the Soil Water Assessment Tool, we simulated high magnitude changes in the water balance from surface runoff to evapotranspiration, which may be a benefit or negative impact depending on context (Benefit 1). We simulated a decrease in soil water storage under rotational grazing, which directly contradicts the outcome assumed in investment literature (Benefit 2). Using the InVEST beta Rangeland Production Model (based on the Century ecosystem model), we simulated increased biomass productivity (Benefit 3) under rotational grazing, which enhanced animal performance under some management parameters but negatively impacted it in others (Benefit 4). We conclude that the impact investing community will likely find greater success through a shift to objective-oriented ranch management, rather than a specific focus on rotation, and will also need additional investment in science and monitoring to demonstrate benefits.

Exit here: Strategies for dealing with aging dams and reservoirs

Aquatic Sciences (Springer) | October 22nd, 2019

Aging infrastructure is prevalent throughout the world, but water control management structures, specifically dams, are of growing concern. Dams and their corresponding r

Aging infrastructure is prevalent throughout the world, but water control management structures, specifically dams, are of growing concern. Dams and their corresponding reservoirs have inherent, but separate, lifespans. The proportion of dams around the world that continue operation beyond their intended lifespans is growing at an alarming rate. Society will not only have to navigate the tradeoffs associated with the deterioration of services provided by reservoirs and dams, but also impending structural failures. Society is nearing a critical pinch point where we will have to decide how to deal with dams and reservoirs at scales that range from a single system to multiple systems in large watersheds. No comprehensive strategy exists to inform both the range of actions that can be applied to such infrastructure and how such actions would influence biophysical, socioeconomic, and geopolitical tradeoffs. The development of proactive exit strategies is a critical first step in ensuring controlled transitions for aging dams and reservoirs. Herein, we present an overview of actions and considerations for aging dams and reservoirs, followed by an initial framework for exit strategy development to launch a further discussion on how society could deal with this aging infrastructure.

Expansion and Intensification of the North American Monsoon During the Pliocene

American Geophysical Union (AGU) | November 10th, 2022

Expert review of the sediment screening guidelines for the beneficial reuse of dredged material in San Francisco Bay, Workshop Summary Report

Publisher not available | March 17th, 2020