German research initiative "Make our planet great again" (MOPGA-GRI) funds four years of r
From November 1st, I will be starting my own research group at the Institute for Atmospheric and Environmental Science at Goethe University in Frankfurt. The program is funded by the German Federal Ministry of Education and Research ("BMBF") and managed through the German Academic Exchange Service ("DAAD").
Figure: Near-global image from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite from Jan. 2nd 2018. Extensive cloud cover over the oceans with a lot of low clouds (i.e. clouds close to the surface) in the Southern Hemisphere and Arctic [source: http://earthdata.nasa.gov].
Clouds, which reside close to the ground are good reflectors of incoming sunlight and trap little heat radiated outward to space. In some sense these clouds shade the Earth’s surface and changes in cloud area or changes in their reflective properties constitute a pretty sensitive temperature dial for Earth’s climate. Any sheet of low-level cloud may span hundreds of kilometers and all together they span around one fifth of Earth’s oceans.
Figure: Illustration of different low-level cloud regimes. Each regime is associated with different dynamical characteristics and radiative properties. Clouds reflect in the shortwave and absorb in the longwave [source: http://earthdata.nasa.gov].
In some regions of the globe, in the mid-latitudes and the Arctic, these clouds do not only consist of water drops, but may contain a mixture of ice particles and water drops. We, as a community, are currently limited in our understanding of how the presence of ice crystals impacts the areal coverage and reflective properties of these clouds at the scale of an entire cloud field as opposed to a single cloud.
To answer this question, we will use satellite retrievals and sophisticated numerical models, which resolve many of the fundamental processes governing the cloud evolution.
Would you like to find out more about the project? Or would like to join the team? Just get in touch under apossner@carnegiescience.edu.