Calendar Event Details
William Collins - 610AT Monthly Seminar
Affiliation: Lawrence Berkley National Laboratory
Event Date: Thursday, May 16, 2013
Time: 3:30 PM
"Early detection of critical climate feedbacks from hyperspectral observations"
One of the central challenges in observing climate change is to detect and attribute alterations in the Earth system that constitute critical climate feedbacks. These feedbacks include alterations in atmospheric moisture, temperature, and snow and ice albedo in response to higher surface temperatures that act to further amplify or moderate the temperature change. Two of the principal issues are the sign and magnitude of cloud feedbacks, and it is debatable whether current surface and satellite observing networks are sufficient to settle these issues. In this talk, I discuss our exploration of the potential for hyperspectral observations of the Earth's reflected visible and near-infrared radiation field and its infrared emission to detect and attribute the responses of clouds to global warming. The two key requirements of these observations are an unprecedented level of calibration stability and the utilization of spectral redundancy to greatly enhance signal-to-noise measures of statistical significance. We have explored these issues using an observing system simulation experiment (OSSE) for climate change that simulates, for the first time, the evolution of Earth's spectrum in both the visible and infrared wavelengths over the 21st century. We show how the use of hyperspectral data can greatly reduce the time to robust detection of cloud responses to global warming relative to conventional broadband measurements of the Earth's radiation field in the longwave, as is well known, as well as in the shortwave, which is a new result produced by this OSSE.
File(s) associated with this entry:
- William Collins CV (pdf file, 152.61 kB)