Clouds reveal where world's most threatened species live

What have clouds to do with conserving threatened species? A lot, say researchers, adding that cloud cover can help identify the size and location of key animal and plant habitats.

Scientists increasingly look to satellite remote sensing as a way to understand habitats and distributions of species.

Researchers from the University at Buffalo and Yale University examined 15 years of data from NASA's Terra and Aqua satellites which orbit and study the Earth.

The comprehensive observations enabled them to build a database containing two images per day of cloud cover for nearly every square km of the planet from 2000 to 2014.

While clouds might seem an odd thing to probe when it comes to mapping species, these sky-bound entities influence factors such as rain, sunlight, surface temperature and leaf wetness that dictate where plants and animals can survive.

The study found that variations in cloud cover sharply delineated the boundaries of ecological biomes, including tropical cloud forests that harbour many species not found anywhere else in the world.

"When we visualised the data, it was remarkable how clearly you could see many different biomes on Earth based on the frequency and timing of cloudy days over the past 15 years," said lead scientist Adam Wilson from Yale.

"As you cross from one ecosystem into another, those transitions show up very clearly, and the exciting thing is that these data allow you to directly observe those patterns at one-km resolution," he added.

Cloud cover also helped the researchers to better predict where specific species live.

By taking cloud patterns into account, the team was able to determine the size and location of habitats for the montane woodcreeper (a South American bird) and king protea (a South African shrub) in unprecedented detail.

"That finding is particularly exciting because the technique could be used to research the habitats of threatened plants and animals," added Walter Jetz, associate professor of ecology and evolutionary biology at Yale in a paper published in the journal PLOS Biology.

Understanding the spatial patterns of biodiversity is critical if we want to make informed decisions about how to protect species and manage biodiversity and its many functions into the future.

The study demonstrates how remote sensing can be a powerful tool in monitoring ecosystems.