Enlarge / A 2-year-old enjoys the spray of water in a splash pad in Los Angeles on June 20, 2022. (credit: Getty | Al Seib )

It's summer, and that means health organizations will be periodically showering Americans with reminders of how public swimming venues are actually nightmarish cesspits teeming with microbes that can burn your eyes, ravage your intestines, and eat your brains .

In attempts to communicate some pretty basic health advice—like, don't pee or poop in a public pool and try to avoid gulping toxic algae from lakes—health organizations create a mesmerizing fountain of hilarious, graphic, disturbing, clumsy, and sometimes perplexing advisories.

Given this wellspring of vomitus summer fun, here are our picks for the top five public health advisories bobbing in the waters this summer.

Enlarge / Aerial view of an abandoned boat on a desert at the site of former Lake Poopó, near Punaca Tinta Maria, Bolivia, taken on October 15, 2022. (credit: Martin Silva/AFP via Getty Images)

Water storage in many of the world’s biggest lakes has declined sharply in the last 30 years, according to a new study, with a cumulative drop of about 21.5 gigatons per year, an amount equal to the annual water consumption of the United States.

The loss of water in natural lakes can “largely be attributed to climate warming,” a team of scientists said as they published research today in Science that analyzed satellite data from 1,980 lakes and reservoirs between 1992 and 2020. When they combined the satellite images with climate data and hydrological models, they found “significant storage declines” in more than half of the bodies of water.

The combination of information from different sources also enabled the scientists to determine if the declines are related to climate factors, like increased evaporation and reduced river flows, or other impacts, including water diversions for agriculture or cities. A quarter of the world’s population lives in basins where lakes are drying up, they warned.

Enlarge (credit: Layland Masuda )

Not for nothing, but when it comes to bodies of water and climate change, the ocean gets the (sea) lion's share of attention. But on land, around 117 million admittedly smaller bodies of water play necessary ecological, social, and economic roles. Lakes are relatively tiny, but "relative" is a key term there—for instance, the Great Lakes of North America account for 20 percent of the Earth's surface freshwater. We also rely on them for food, fresh water, transportation, and more.

New research identifies the interrelated challenges that the world's lakes face. According to Sapna Sharma, co-author of the research and an associate professor of York University's biology department, many of the climate change-related impacts that these watering holes remain relatively hidden despite these waters potentially facing an extensive collection of problems. "I hope that people get a sense of how widespread the effects of climate change on lakes are," she told Ars. "If you just go look out at a lake, you might not know all the changes it's experiencing."

To study this, Sharma and colleagues at different universities around the world pored over hundreds of research papers about lakes. These papers came from across the globe, and some date back to the 1930s, she said. Sharma and her fellow researchers all have differing areas of expertise, allowing them to review and synthesize the existing literature.