Solar Geoengineering Seminar Series


Wednesday, October 16, 2019, 12:00pm to 1:00pm


Harvard University Center for the Environment, 26 Oxford Street, Room 440

"Cirrus seeding: Understanding the complicated little sister of stratospheric geoengineering"


Ulrike Lohmann, Department of Environmental Systems Science, ETH Zurich.


Amy Chang

Lunch is provided with RSVP to


David Keith, Faculty Associate. Gordon McKay Professor of Applied Physics, Harvard John A. Paulson School of Engineering and Applied Sciences; Professor of Public Policy, Harvard Kennedy School.


Climate engineering is a potential means to offset the climate warming caused by anthropogenic greenhouse gases. The most prominent and best researched climate engineering approach to alter Earth’s radiation balance is the injection of atmospheric aerosol particles or their precursor gases into the stratosphere, where these particles reflect solar radiation back to space. Climate engineering through cirrus cloud thinning, in contrast, mainly targets the longwave radiation that is emitted from Earth. Because cirrus clouds warm the climate, reducing their coverage and optical thickness leads to a cooling. In the talk, cirrus seeding will be discussed in all facets.