India’s Rising Suicide Rate Linked to Climate Change
Climate change has already caused more than 59,000 suicides in India over the last 30 years, according to estimates in a study published in Proceedings of the National Academy of Sciences in July. Research suggests that failing harvests that push farmers into poverty are likely the key culprits.
Tamma Carleton, a doctoral candidate in the Department of Agricultural and Resource Economics, discovered that warming by 1 degree Celsius (1.8 degrees Fahrenheit) on a single given day during India’s agricultural growing season leads to roughly 65 suicides across the country whenever that day’s temperature is above 20 degrees Celsius (68 degrees Fahrenheit). Warming by 5 degrees Celsius under the same temperature conditions has five times that effect.
Heat drives crop loss, Carleton contends, which can cause ripple effects throughout the Indian economy as poor harvests drive up food prices, shrink agricultural jobs, and deplete household savings. The study demonstrates that warming—forecast to reach 3 degrees Celsius by 2050—is already taking a toll on Indian society.
Using methods that she developed in a previous paper, published in the journal Science, Carleton projects that the suicide rate will only rise as temperatures continue to warm.
Debate about solutions to the country’s high and rising suicide rate, which has nearly doubled since 1980 and claims more than 130,000 lives each year, is contentious and has centered on lowering economic risks for farmers. In response, in 2016 the Indian government established a $1.3 billion crop insurance plan aimed at reducing the suicide rate—but it is unknown if that will be effective or sufficient.
Carleton said she hopes her work will help people better understand the human costs of climate change, as well as inform suicide prevention policy in India and other developing countries. “The tragedy is unfolding today. This is not just a problem for future generations. This is our problem, right now,” she said. “The right policies could save thousands.”
— Adapted from an article by Kathleen Maclay
Engineering a Sugar That's Good for You
Kulika Chomvong and Chaeyoung Shin, cofounders of Sugarlogix.Photo by Or Weizman
Kulika Chomvong and Chaeyoung Shin want the world to eat more sugar. The two are cofounders of Sugarlogix, a start-up cultivating prebiotic sugars. “We make healthier sugars for healthier products,” said Chomvong, PhD ’16 Plant and Microbial Biology. “We want to make sugars that are worth getting addicted to.”
The duo met on campus at the Energy Biosciences Institute while working at separate ends of the same problem.
Chomvong was engineering yeast suitable for the production of fuel from cellulose, while Shin—a chemical engineering doctoral student—was refining the biofuel fermentation process itself. After graduating in 2016, the two pivoted to the production of prebiotic sugars.
Many people are familiar with probiotics, live cultures of “good” gut bacteria found in foods like yogurt and kombucha. In contrast, prebiotic sugars—also called prebiotics—are nondigestible compounds that promote the growth of intestinal microflora. Probiotics are living bacteria, whereas prebiotics are the nonliving chemical compounds on which intestinal flora feed.
“What we’re doing is re-creating the food for good gut bacteria,” said Chomvong, and the result could be a positive impact on gut health. While anyone can benefit from a healthier gut, Chomvong is optimistic that prebiotics would most benefit individuals with depleted levels of gut bacteria, such as those who have recently taken antibiotics.
Currently, Sugarlogix is focusing on how prebiotics could help infants, by culturing human milk oligosaccharides, or HMO. Compounds similar to HMO—called galacto-oligosaccharides, or GOS—occur naturally in the milk of other mammals and have been used as an additive in infant formula for years. A study co-published by the National Center for Biotechnology Information and the National Institutes of Health found that infants given formula supplemented with GOS showed gut health consistent with that of breast-fed infants. Chomvong and Shin believe they would see similar if not superior results for infant formula supplemented with HMO.
Although prebiotics can’t replace sweeteners, as an additive to infant formula they could lead to healthier babies. And as Sugarlogix develops prebiotics for a wider audience,
Chomvong and Shin hope its products can someday promote healthy intestinal flora in adults, too.
— Adapted from an article by Cirrus Wood in Berkeleyside
From left: Mary Firestone, N. Louise Glass, Susan Hubbard, Margaret Torn
ESPM professor Mary Firestone was elected to the National Academy of Sciences in May. Firestone’s research examines the fundamental understanding of soil microbial ecology and its applications to issues such as climate change, sustainability, and biodegradation.
Plant and microbial biology professor N. Louise Glass was named a fellow of the Mycological Society of America in July. Glass is a leading researcher in the molecular genetics of Neurospora, including the genetics of mating, non-self recognition, and lignocellulose decomposition.
Also in July, Susan Hubbard and Margaret Torn were elected fellows of the American Geophysical Union. Hubbard is an adjunct ESPM professor and the associate lab director of the Earth and Environmental Sciences Area at the Lawrence Berkeley National Laboratory (Berkeley Lab). Torn is an adjunct ERG associate professor and a senior scientist in Berkeley Lab’s Earth and Environmental Sciences Area.
Mapping the Cost of Climate Change
A new study co-led by two UC Berkeley researchers predicts that if climate change continues unmitigated through the end of the century, the poorest third of U.S. counties will likely lose up to 20 percent of their incomes, and regions such as the Pacific Northwest and New England will gain economically over the southern and Gulf states.
The research concludes that for every 1-degree-Fahrenheit increase in global temperatures, the U.S. economy stands to lose about 0.7 percent of its gross domestic product.
Published June 29 in the journal Science, the analysis was led by Solomon Hsiang, a professor in the Goldman School of Public Policy, and James Rising, a postdoctoral researcher in the Energy and Resources Group (ERG).
Their study combined 116 forecasts and numerous economic analyses developed by scientists around the world to assess costs and benefits of unmitigated climate change for crime, agriculture, energy, labor, coastal communities, and mortality.
Rising and Hsiang say that the study results can be useful to everyone from policy makers and public utility officials to farmers and law enforcement officials, as well as those in the tourist industry and disaster relief organizations.
- Rising mean sea levels linked to stronger, more frequent tropical cyclones will amplify storm tide heights and extend floodplains, worsening problems for low-lying coastal cities and inflicting direct economic damages on them.
- Agricultural yields in the Midwest will decline dramatically with rising global mean surface temperatures.
- Annual national mortality rates will rise by roughly five deaths per 100,000 people for each 1-degree-Celsius (1.8-degrees-Fahrenheit) increase in temperature.
- Owing to more hot days, electricity demands will increase for all regions except the Rockies and the Pacific Northwest.
- For each additional degree of rising global mean surface temperature, the number of hours worked will decline by about 0.11 percent for workers who are not generally exposed to outdoor temperatures and by 0.53 percent for high-risk, outdoor workers in sectors like agriculture, construction, manufacturing, and mining.
- Property crimes will increase in the Northeast as the number of cold days decreases. Meanwhile, violent crime rates will increase across the country by about 0.9 percent per each additional degree Celsius in global mean surface temperature.
— Adapted from an article by Kathleen Maclay
Cannabis Crop Expansion Threatens Wildlife Habitats
Planting cannabis for commercial production in remote locations creates forest fragmentation, stream modification, soil erosion, and landslides. Without land-use policies to limit its environmental footprint, the impacts of cannabis farming could get worse, according to a new study published in Frontiers in Ecology and the Environment.
“To mitigate the anticipated environmental impacts, now is the time for policy makers and land-use planners to set regulations to manage the spatial pattern of cannabis expansion, before crop production becomes established,” said co-author Van Butsic, a Cooperative Extension specialist in the Department of Environmental Science, Policy, and Management (ESPM).
Cannabis, as either a medicinal or a recreational drug, is now legal in more than 30 U.S. states and several other countries. In California, where medicinal marijuana has been legal since 1996, voters approved the sale and possession of one ounce of marijuana per person for recreational use in November of last year. As a result, cannabis production is ramping up.
Earlier studies have shown that cannabis production causes environmental damage, including the rodenticide poisoning of forest mammals and the dewatering of streams due to improper irrigation.
In this study, Butsic, ESPM assistant professor Ian Wang, and Jacob Brenner of Ithaca College compared the effects of cannabis cultivation in Humboldt County from 2000 to 2013 with those of timber harvests during the same period. Based on the size, shape, and placement of the cannabis grows within 62 randomly selected watersheds, they quantified the grows’ impacts relative to those of timber harvests.
“We found that although timber has greater landscape impacts overall, cannabis causes far greater changes in key metrics on a per-unit-area basis,” Butsic said.
The cannabis grows resulted in 1.5 times more forest loss and 2.5 times greater fragmentation of the landscape, breaking up large, contiguous forests into smaller patches and reducing wildlife habitats.
Current California law caps the size of outdoor cannabis production at one acre per parcel, to prohibit the development of industrial-scale cannabis operations outdoors. An unintended consequence of this law may be smaller, dispersed cannabis grows that edge out wildlife.
— Adapted from an article by Pamela Kan-Rice