SALTON SEA | California

As drought fueled by climate change batters the American West, evaporation and a decreased inflow of agricultural runoff from surrounding farms are causing California’s Salton Sea to shrink. Today, the state’s largest and most polluted lake teeters on the brink of ecological collapse. Residents living in its vicinity face the threat of toxic dust. As the soil dries and the winds stir, the lake’s parched shores emit hazardous dust laced with arsenic, selenium, and pesticides—remnants of a century's worth of agricultural runoff. Respiratory illness in the area is already widespread, and in Imperial County, children visit emergency rooms for asthma-related symptoms at double the average statewide rate. The lake’s future now stands at a precipice: protracted drought and reductions in inflow from the overextended Colorado River threaten to accelerate the beleaguered lake’s decline. If the shoreline continues to recede, an estimated 100 tons of lung-damaging dust could blow off its shores daily by 2045.

The circumstances at the Salton Sea represent a microcosm of an alarming global phenomenon: Earth’s largest lakes are drying out. According to a 2023 study published in the journal Science, over half of the planet’s large lakes have diminished in size over the last three decades, and approximately one-quarter of the population worldwide currently resides in the basin of one of these shrinking water bodies. Terminal lakes—landlocked bodies of water that have no drainage, like the Salton Sea—are particularly vulnerable to climatic and agronomic stressors. A combination of evaporation and water diversion has caused Lake Chad in Central Africa to shrink by 90%, leaving behind a desert region that is currently one of the largest sources of dust on the planet. Lake Urmia in northwest Iran has diminished to 10% of its former size, and both the Aral Sea in Central Asia and Lake Poopó in Bolivia have completely disappeared.