The truth about cookstove carbon credits
Annelise Gill-Wiehl (second from left) and her local research partners teach women in rural Tanzania how to use clean-burning liquified petroleum gas stoves, one of the few models that have both health and climate benefits.
Photo courtesy Annelise Gill-Wiehl.The fastest-growing type of offset on the global carbon market subsidizes the distribution of efficient cookstoves in developing countries to reduce greenhouse gas emissions, but a study by UC Berkeley researchers finds that the stoves’ carbon-saving credits are vastly overestimated, by a factor of ten.
The overestimation undermines efforts to counteract carbon emissions to slow climate change, since companies can use offsets to meet climate targets and sell products labeled as “carbon neutral” instead of making real reductions in greenhouse gas emissions.
“Estimated correctly, carbon offsets have the potential to support the free or subsidized distribution of efficient stoves that reduce time spent collecting firewood or the cost of purchasing fuel,” said first author Annelise Gill-Wiehl, a PhD candidate in the Energy and Resources Group (ERG), who has conducted extensive household energy fieldwork in East Africa. “What’s more, certain stoves can reduce smoke exposure enough to ultimately save lives.”
Published in Nature Sustainability in January, the study was the first comprehensive, quantitative quality assessment of any type of offset project. Barbara Haya, PhD ’10 ERG, director of the Berkeley Carbon Trading Project, and Daniel Kammen, the James and Katherine Lau Distinguished Professor of Sustainability, are co-authors of the study. The authors also offer a companion website with a summary of findings, background materials, and guidance for cookstove offset project developers and credit buyers who want to trade in quality credits that can substantially improve health and reduce emissions.
Want to preserve groundwater?
Tax it.
During the early 1980s, farmers in the Pajaro Valley, a California region known for its ample apple orchards and strawberry fields, suffered an agricultural disaster. Years of overpumping groundwater created space for seawater to enter the coastal aquifer that farms and ranches relied on, devastating crops irrigated with this salty water.
In response, voters agreed to create the Pajaro Valley Water Management Agency to manage local water supplies and prevent future groundwater overdraft. The agency began metering groundwater in 1994 and charging based on usage. To avoid groundwater overdraft near the coast, the agency also began piping in irrigation water to certain areas known as the Delivered Water Zone (DWZ). Beginning in 2010, agricultural customers who received water deliveries were required to pay an additional fee.
Economists like Ellen Bruno, a professor of Cooperative Extension in Agricultural and Resource Economics, have long thought that charging for groundwater could incentivize customers to manage their water use more efficiently without mandating specific changes. Although such charges are rarely enacted in California, the Pajaro Valley’s separate charge for service in the DWZ gave Bruno the opportunity to study the effect of what amounts to a tax on groundwater.
After analyzing the five-year periods before and after the implementation of the DWZ charge, Bruno and collaborators found that groundwater demand in the Pajaro Valley shrank in response to long-term price increases. Specifically, DWZ customers who faced an average 21 percent increase in the price of groundwater reduced their average annual extraction by 22 percent.
These findings, which were featured in Bloomberg and the New York Times, could have significant implications for groundwater management in California, especially as local regulators face a 2040 deadline to achieve groundwater sustainability.
A commitment to conservation
The view looking south from the top of Heart Mountain toward Cody, Wyoming, where the Beyond Yellowstone Program centers its work.
Photo by Kristin Barker.Established last fall with a five-year, $2.5 million gift from the James M. and Cathleen D. Stone Foundation, the Stone Center for Environmental Stewardship at UC Berkeley is dedicated to advancing the conservation and restoration of ecologically and culturally important wildlife in the United States through community-engaged research, training, outreach, and policy work. The Center will create several Living Labs in specific landscapes where researchers and local partners collaborate to identify conservation priorities, evaluate solutions, monitor outcomes, and connect with policymakers. The Center’s first Living Lab is the Beyond Yellowstone Program, led by Professor Arthur Middleton and colleagues from the University of Wyoming, which focuses on studying and sharing the story of the Yellowstone ecosystem’s wildlife, lands, and people in support of landscape-scale conservation. “The Center will leverage Berkeley’s interdisciplinary research capabilities, leadership in environmental problem-solving, and ability to connect experts to local partners and policymakers, allowing us to increase the pace, scale, equity, and durability of landscape conservation,” said Middleton.
Beyond tired
When you think about what causes cancer, you might be quick to name chemicals like tobacco or radiation sources like ultraviolet light. But a recent study co-authored by Nutritional Sciences and Toxicology professor David Moore identifies another cause: prolonged shift work, chronic jet lag, and other circadian rhythm dysfunctions. After exposing mice with both human and rodent liver cells to conditions that mimicked the jet lag associated with many weeks of international travel, Moore and co-authors from the Baylor College of Medicine observed increased rates of cirrhosis, jaundice, and liver cancer compared to mice that were kept in sync with the natural day-and-night cycle. “Our work shows that circadian influences in cancer cannot be underestimated: chronic circadian dysfunction is a human carcinogen,” Moore said.
In Their Own Words
Did California’s overtime law help agricultural workers?
Farmworkers are vital to the success of California’s agricultural industry and the broader agrifood system, yet many face economic, social, and health-related challenges. Nearly two-thirds of California crop workers have household incomes below 200 percent of the federal poverty level, more than half self-identify as undocumented, and their jobs are regularly ranked as highly dangerous.
These and other challenges have, in part, been attributed to historical discrimination and the resulting exclusion of farmworkers from federal labor laws, including laws with protections related to youth employment, unionization, minimum wages, and overtime standards. In 2016, California passed legislation to gradually phase in overtime standards beginning in 2019. Since then, four other states—New York, Washington, Oregon, and Colorado—have passed similar legislation.
Overtime regulations aim to improve worker well-being by requiring higher pay for working long hours. However, worker incomes could fall if employers reduce hours to avoid paying overtime rates, making workers who value extra income more than additional leisure time worse off. In this case, employers would also need to hire additional workers, invest in labor-saving technology, or make larger changes like switching to less labor-intensive crops.
My research using the National Agricultural Workers Survey shows that in the two years following the phase-in of California’s overtime standards for agricultural workers, the average California crop worker experienced reduced hours and earnings. Fewer workers worked at or just below the prior overtime threshold of 60 hours per week, and more worked at or just below the 2020 threshold of 50 hours per week. Reduction in hours was accompanied with decreases in workers’ weekly take-home pay. These changes are consistent with employers cutting individual worker hours to remain under overtime thresholds.
This early evidence suggests that the law may not be benefiting the workers it aims to protect, but additional research is needed. It is possible that despite these outcomes, workers are happy to accept the lower pay in exchange for fewer working hours and more leisure time. Additionally, the law might have led to increased job opportunities in agriculture, improving well-being for previously unemployed or underemployed individuals, or resulted in safer working environments, since research suggests longer hours can increase workplace injuries. On the other hand, workers and their families who were depending on this lost income may now need to seek out additional employment opportunities, negating these other benefits and adding the inconvenience of traveling between jobs. I am currently exploring these and other outcomes using alternative data sources.
Alexandra Hill is an assistant professor of Cooperative Extension in the Department of Agricultural and Resource Economics whose research and outreach aims to advance diversity, equity, and inclusion in the agrifood system. A longer version of this article originally appeared in ARE Update, published by the Giannini Foundation of Agricultural Economics.
Not in my backyard?
Wind power is one of the fastest-growing renewable energy sources, but its implementation often faces significant challenges from local communities, partly from resistance to visible wind turbines and the assumed implications for property values.
A study published this March in the Proceedings of the National Academy of Sciences shows, however, that the values of houses in the United States within a wind turbine’s viewshed drop only slightly and temporarily due to disrupted views. The effect is smaller the farther away the turbines are and fades over time. The research was conducted by Maximilian Auffhammer, a professor in the Department of Agricultural and Resource Economics (ARE), Wei Guo, PhD ’23 ARE, and former ARE postdoctoral researcher Leonie Wenz, now at the Potsdam Institute for Climate Impact Research.
After statistically analyzing data from more than 300 million home sales and 60,000 wind turbines from 1997 to 2020, the team found that the impact of wind turbines on house prices is much smaller than generally feared. “In the U.S., it’s about one percent for a house that has at least one wind turbine in a 10-kilometer radius,” explains Auffhammer. “And surprisingly, the house value bounces back to the original price over time.” The study authors also found that there was no longer any effect for wind turbines built after 2017, a phenomenon they suggest could be due to people getting used to these new structures in their environment.
Hot off the press
Sweet Deal, Bitter Landscape
Gender Politics and Liminality in Tanzania’s New Enclosures
Cornell University Press
In the mid-2000s the Tanzanian government struck a deal with a foreign investor to convert more than 20,000 hectares of long-settled coastal land into a sugarcane plantation, but abandoned the plan a decade later. With rich ethnographic detail and visual storytelling, Assistant Professor Youjin Chung traces the profound implications the incomplete processes of development and dispossession had for the rural people there.
Disabled Ecologies
Lessons from a Wounded Desert
University of California Press
Assistant Professor Sunaura Taylor tells the story of the contamination of an aquifer in Tucson, Arizona, and its ripple effects through the largely Mexican American community living above. Drawing on her own complex relationship to this long-ago injured landscape, Taylor offers a powerful analysis and call to action that reveals disability as one of the defining features of environmental devastation and resistance.
Toxic Water, Toxic System
Environmental Racism and Michigan’s Water War
University of California Press
Drawing from three years of ethnographic fieldwork in Detroit and Flint, Michigan, Professor Michael Mascarenhas amplifies the voices of marginalized communities, particularly African American women, whose perspectives and labor are consistently overlooked. The book exposes the consequences of a seemingly anonymous authoritarian state willing to maintain white supremacy at any cost—including poisoning an entire city and shutting off water to thousands of people.
Learn more and listen to a recording of the faculty discussing their books on the ESPM website.
Investigating coral reef viruses
In addition to well-known threats to coral reefs like mass bleaching and ocean acidification, stony coral tissue loss disease (SCTLD) has been decimating coral reef communities at an alarming pace.
Infected colonies exhibit rapidly expanding lesions that consume the coral’s living tissue, killing even large corals in mere months. Scientists are working to determine the cause of SCTLD—which was first observed off the Florida coast in 2014 and has since been reported in 28 Caribbean nations—and to identify treatments that slow its spread.
Lauren Howe-Kerr collects a tissue biopsy of the branching coral, Acropora hyacinthus, off the coast of Mo’orea, French Polynesia.
Courtesy of the Correa Lab.Filamentous viruses have gained recent attention as a possible contributor to the disease. However, a study co-authored by Environmental Science, Policy, and Management professor Adrienne Correa in November shows that filamentous viruses may be globally distributed in corals and are not a component unique to this devastating disease.
Researchers in Correa’s previous lab at Rice University identified filamentous virus-like particles (VLPs) in images of healthy and bleached coral samples collected in the waters surrounding the South Pacific island of Mo’orea, even though SCTLD has not been reported in the Pacific Ocean basin. “This tells us that filamentous VLPs are not solely associated with SCTLD and that we need to take a much closer look at what various kinds of viruses are doing,” explained Lauren Howe-Kerr, who led the research while a postdoctoral researcher at Rice University.
Correa, who has studied coral reef virology for the past 14 years and joined the Berkeley faculty last fall, also stressed the importance of better understanding how viruses and microorganisms affect coral colonies’ overall health. To advance that goal, her lab is collaborating with scientists from the Smithsonian and Oregon State University at UC Berkeley’s Gump Research Station on Mo’orea to deep sequence corals and other reef organisms—including their resident viruses.
— Mathew Burciaga