Satellites may be providing scientists with the missing information they need to learn more about climate change. Researchers from the Hebrew University of Journalism in Israel have found a way to measure information that they needed in order to show human responsibility for our changing climate.
"This new satellite methodology enables us to quantify climate effects on a global scope, provides a more accurate assessment of the processes affecting global warming, and reduces the uncertainty there is about climate change," said Daniel Rosenfeld, an expert on climate change from the Hebrew University's Institute of Earth Sciences.
Greenhouse gas emissions from manmade sources have long been seen as one of the major causes for global warming. These gases actually slow the release of heat that radiates from Earth to space and actually reflect heat back to the planet.
However, there are some manmade particles that actually counter this effect. Smoke, dust, and other kinds of pollution particles, called Cloud Condensation Nuclei, have a particular effect on Earth's clouds. Polluted clouds contain a higher number of smaller droplets, which makes them brighter, and the smaller cloud droplets are slower to coalesce to raindrops. This makes the clouds persist for a longer period of time and reflect solar radiation back into space. In other words, this causes the Earth to be cooler.
However, researchers were previously sure exactly how to measure these particles to get a global view of their abundance and properties. This means that they weren't able to say exactly what effect these particles had on climate change.
But now, researchers have a new technique to measure the particles. They've used an existing meteorological satellite, operated since 2012, in order to determine cloud-based updraft speeds and quantify the particles' ability to create cloud droplets. This, in turn, could help researchers better understand what effect they have on the climate and how this factors into climate change models.
"Such measurements are very sparse, whereas quantifying climate effects requires conducting such measurements at a global coverage, which is possible only with satellites," Rosenfeld said.
The new findings are an important part of better understanding how climate change is affecting our planet. By seeing how these particles influence clouds, researchers can assess how much radiation is being reflected back into space.
The research was published in the March 4 issue of the journal Proceedings of the National Academy of Sciences.
