Eureka!

Reading the Sky

Scientists are looking to the clouds to help us track endangered species on Earth

By Charlotte Hsu

“We now have almost 40 years of satellite images we can use to understand past changes.”
Adam Wilson

They are beautiful to behold: feathery cirrus clouds, stretched out across the sky like wings. Puffy cumulus clouds, which resemble cotton candy. And moody nimbostratus clouds, blanketing the horizon in startling silver sheets.

But for UB geographer Adam Wilson, these sky-bound formations hold an allure beyond their aesthetic appeal. He reads the clouds for clues to where plants and animals live on Earth. Wilson published a study last spring with Yale University colleague Walter Jetz, showing how variations in cloud cover can outline the boundaries of ecological biomes as well as the stomping grounds of individual species. The duo used cloud patterns to plot with amazing precision the size and location of two species’ habitats: a South American bird called the montane woodcreeper and a South African shrub known as the king protea. Their techniques could aid conservation efforts, allowing scientists to get a more accurate picture of where wildlife is found on Earth, including in remote locations that are hard to access.

The king protea, a South African shrub, has been tracked by scientists using cloud data.

“Observing ecological processes on the ground is, in many ways, the best approach. But it’s also very expensive and time-consuming. We’ll never be able to replace fieldwork, but this approach is a powerful supplement that can help fill in the gaps and monitor change through time,” says Wilson, an assistant professor of geography who completed much of the research as a postdoctoral fellow at Yale.

Wilson and Jetz also have constructed an innovative cloud atlas, an online mapping tool that lets users explore cloud coverage worldwide over a 15-year period, from 2000 to 2014. The data came from the researchers’ painstaking analysis of images from NASA satellites that have been orbiting the Earth for decades, while snapping photos, twice a day, every day, of nearly every square kilometer of the planet.

Wilson says clouds are a largely untapped source of information when it comes to monitoring biodiversity—and a particularly powerful one, because they help control a plethora of factors that influence plant and animal survival. Clouds affect not only the amount of sunlight and rain that hit the Earth, but also such related attributes as the temperature of the air and the ground, and even leaf wetness.

Clouds have been used to obtain information on the habitat of the montane woodcreeper.

In the past, scientists looking for cloud data had to rely on observations from weather stations. This left large swaths of land unmonitored, creating serious limitations for research because traits like temperature and precipitation can vary significantly across even small regions. But technology has given us new ways to get our heads in the clouds.

“We now have almost 40 years of satellite images we can use to understand past changes and improve our ability to predict future change in our environment,” Wilson says. “It’s an incredibly rich archive; we’re really just getting started.”