Data derived from earth orbiting satellites are becoming increasingly popular in monitoring the environment. On one hand, the large spatial coverage that these data provide, make it much easier for scientists to “access” areas that are otherwise impossible to reach. On the other hand, specific characteristics of the data allow precise estimation of variables that are otherwise too difficult, or time/labor consuming to measure at large scale. These include chemical composition of both atmosphere and earth surface, gravity, ice thickness, among many others.
A team from the Hebrew University of Jerusalem, led by professor Daniel Rosenfeld, developed a new rapid method to monitor man-introduced pollutants in the atmosphere. Until now, these have been very difficult, or in fact, near impossible, to accurately monitor and measure at a global scale. Scientists could only rely on aircraft-derived data, or data derived from ground stations, which are location limited.
In the paper published in the journal Proceedings of the National Academy of Sciences, the team from Jerusalem proposed an innovative approach, where meteorological satellite data is used to determine two major atmospheric characteristics: the ability of aerosol particles to form clouds and the speed of cloud-base updraft.
These two characteristics, or factors, closely determine the intensity of greenhouse gas effect, and consequently climate change. The explanation behind this is that polluted clouds are rich in small droplets, which are generally slower to form rain drops. Thus, the lifespan of the clouds is prolonged, meaning that radiation cannot escape, and stays trapped under the clouds for longer time. Consequently, the greenhouse gas effect is worsened.
With the new technique, the team managed to add some missing pieces to the huge puzzle that is climate change. What is more, they managed to provide a mean to reduce the uncertainty, and therefore shutting up some of the deniers, who claim that man-made climate change is fiction.
Understanding climate change can only happen if we look at processes on a global scale. Satellite data provide us with this opportunity. With the numerous newly available sensors in space, the possibilities for such incredible scientific discoveries are becoming endless.
Image (c) Meinrat Andreae