More than half the world’s largest lakes shrank over the past three decades, threatening the wildlife ecologies and vast human populations in those regions. To examine this issue, including the shrinking Salton Sea in California, UCR Distinguished Professor and Wilber W. Mayhew Endowed Chair in Geo-Ecology Tim Lyons is heading to Yale.
“Drying lakes are an aspect of climate change that has been underappreciated, given that over a quarter of the world’s population lives in basins experiencing water loss,” Lyons said. “As drought and increased demand for drinking and irrigation water dry them out, they leave behind dust laden with pesticides, biological pathogens, and potentially toxic metals that pose serious health issues.”
Lyons has been designated an Edward P. Bass Distinguished Visiting Environmental Scholar and will begin a six-month period of research on receding lakes at the Yale Institute for Biospheric Studies, or YIBS, starting in Spring 2024. The program brings premier scholars in any field dealing with environmental studies to Yale on the nomination of the institute’s faculty affiliates.
“Because I did my Ph.D. work at Yale, it’s particularly heartening to see how much leadership the school is showing on issues related to the climate and sustainability. YIBS has played a major role in that arena,” Lyons said.
For this fellowship, Lyons was nominated by one of his former UCR Ph.D. students, Noah Planavsky, now a professor in the Department of Earth and Planetary Sciences at Yale. Planavsky will serve as Lyons’ host, and the two geochemists will use traditional and novel techniques to study issues specific to the Salton Sea but with potential for investigating drying lakes worldwide and the threats they pose.
At 350 square miles, the Salton Sea is California’s largest lake, and possibly one of its most polluted. Although alternating between wet and dry conditions naturally over the thousands of years, the present lake formed in 1905 when Colorado River floodwater breached an irrigation canal in the Imperial Valley. It is a terminal lake, meaning water flows in but has no outlet. Water levels have been maintained since this event by agricultural runoff, which has been decreasing dramatically in recent years due to changes in climate and water policy.
Salt flows in and stays, resulting in a salinity level that is almost twice that of the ocean. There are also well-documented problems related to elevated levels of nitrogen, phosphorus, and other elements from fertilizers in the water, as the sea is adjacent to one of the country’s largest farming areas. Algae and bacteria thrive on these components, resulting in blooms that decay into “dead zones” where fish suffocate.
Algae and bacteria can be transported by the wind and inhaled, causing respiratory problems in humans. The dust emerging from the drying lake is also a concern, with the added threats of metals and pesticides now residing in the muds on the lake floor.
Lyons and Planavsky will “fingerprint” the sea muds and related dust to learn precisely what chemicals and pathogens are present and where they are spreading, including the portions delivered into the lungs of people living nearby. The team hopes to understand what part of the sea might produce the most harmful dust and how far it might travel throughout the region. This understanding will help inform choices among the various solutions being considered.
Most importantly, they hope their data will reveal which areas of the sea are most important to keep wet, what percentage of the lake should stay wet, and whether there is anything that can be done about the harmful sediment already there. To this end, Lyons has been working closely with UCR graduate student Caroline Hung and postdoc Charlie Diamond.
At UCR, Lyons is a leader of the Salton Sea Task Force, a group of faculty from multiple departments dedicated to understanding the issues with the Salton Sea and recommending solutions to policymakers. Group members share a concern about the expected population growth in the area surrounding the sea with expanding efforts to mine lithium for electric vehicles and smartphones.
“With the lithium industry showing so much promise, there is talk of moving a lot of people to Imperial County to build lithium extraction plants, related infrastructure and manufacturing, and potentially to conduct battery research,” Lyons said. “I do not believe the industry fully recognizes the threats that loom for existing and growing populations.”
Present degradation of air and water quality are already major health concerns, and growth in the area only elevates the potential for harmful consequences as material spreads via winds throughout the immediate region and extending into Coachella Valley. Presently, the full distribution of potential human impacts is not known.
Though lithium extraction is specific to this areas, drying lakes are a global challenge. The Aral Sea in central Asia, once the fourth largest lake in the world, has been slowly disappearing for decades. Similar story for Lake Chad in west central Africa; Lake Urmia in northwestern Iran; Lake Poopó in Bolivia, which dried up completely in 2015; and the Great Salt Lake in Utah, at risk of disappearing within five years.
Lyons expressed gratitude for the opportunity to increase the profile of Salton Sea issues in California with his fellowship at Yale and hopes to direct academic and public attention more generally to the issue of drying lakes throughout the world.
“My goal ultimately is to have people from all over the world come together and talk about our common problems and, by learning from each other, converge on a set of steps we can take to best manage our dwindling resources,” Lyons said.