Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder

Cryospheric and Polar Processes Seminar

Known Knowns, Known Unknowns, and Unknown Unknowns about Uncertainties in Passive Microwave Sea Ice Data By Walt Meier, Senior Research Scientist, DAAC Scientist, National Snow and Ice Data Center, CIRES, University of Colorado
Sea ice data from passive microwave sensors are the basis for one of the longest satellite-derived climate records. While there are many advantages in using passive microwave sensors for sea ice, including complete and consistent daily coverage, there are also many known uncertainties in using the data. These known uncertainties are helpful in guiding use of the data. However, there are many aspects of the uncertainties that are not well known, particularly at the grid cell level. Only recently have some sea ice concentration products started to provide grid cell uncertainty estimates. However, these uncertainty estimates have not themselves been validated – they are unknown unknowns. This talk will focus on recent efforts to validate the concentration uncertainty estimates through comparisons with concentrations derived from visible and infrared imagery. It will also present background on passive microwave sea ice fields and discuss uncertainties in total sea ice extent estimates.

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Wednesday, November 29, 2017
11:00 am to 12:00 pm




  • CIRES employees
  • CU Boulder employees
  • General Public
  • NOAA employees
  • Science collaborators
  • Open to Public



East Campus, RL-2, Room 155