Events
DMS Statistics and Data Science Seminar |
| Time: Nov 19, 2020 (02:00 PM) |
| Location: ZOOM |
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Details: Speaker: Mikael Kuusela (Statistics and Data Science, Carnegie Mellon University) Title: Objective Frequentist Uncertainty Quantification for Atmospheric Carbon Dioxide Retrievals
Abstract: The steadily increasing amount of atmospheric carbon dioxide is having an unprecedented impact on the global climate system. In order to better understand the sources and sinks of CO2, NASA operates the Orbiting Carbon Observatory-2 & 3 instruments to monitor CO2 from space. These instruments measure the radiance of the sunlight reflected off the Earth's surface, which is then inverted to obtain CO2 estimates. In this work, we first analyze the current operational retrieval procedure, which uses a prior distribution to regularize the underlying ill-posed inverse problem, and demonstrate that the resulting uncertainties might be poorly calibrated both at individual locations and over a spatial region. To alleviate these issues, we propose a new method that uses known physical constraints and direct inversion of functionals of the CO2 profile to construct well-calibrated frequentist confidence intervals based on convex programming. Furthermore, we study the influence of individual nuisance variables on the length of the intervals and identify certain key variables that can greatly reduce the final uncertainty given additional deterministic or probabilistic constraints. This is joint work with Pratik Patil (Carnegie Mellon University) and Jonathan Hobbs (Jet Propulsion Laboratory).
Seminar website: http://webhome.auburn.edu/~ezc0066/stat-datasci-seminar.html Join from PC, Mac, Linux, iOS or Android: https://auburn.zoom.us/j/93758346031 —————————————————————————————————————————————————————————— More details on the Zoom meeting.
Topic: Statistics & Data Science Seminar Time: Nov 19, 2020 02:00 PM Central Time (US and Canada)
Join from PC, Mac, Linux, iOS or Android: https://auburn.zoom.us/j/93758346031 Connect using Computer/Device audio if possible.
Or Telephone: Meeting ID: 937 5834 6031 Dial: +1 646 876 9923 (US Toll) or +1 301 715 8592 (US Toll)
Or an H.323/SIP room system: H.323: 162.255.37.11 (US West) or 162.255.36.11 (US East) Meeting ID: 937 5834 6031
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