1. workbook DAAC Product Review Passive Microwave Data Sets Walt Meier

2. workbook DAAC Product Review 2 The Passive Microwave Data Sets Product IDSubsetName NSIDC-0001Brightness TemperatureDMSP SSM/I Daily Polar Gridded Brightness Temperatures NSIDC-0032Brightness TemperatureDMSP SSM/I Pathfinder Daily EASE-Grid Brightness Temperatures NSIDC-0036Brightness TemperatureNimbus-7 SMMR Pathfinder Brightness Temperatures NSIDC-0037Brightness TemperatureNimbus-7 SMMR Antenna Temperatures NSIDC-0071Brightness TemperatureNimbus-7 SMMR Pathfinder Daily EASE-Grid Brightness Temperatures NSIDC-0077Brightness TemperatureNimbus-5 ESMR Polar Gridded Brightness Temperatures NSIDC-0080Brightness TemperatureNear Real-Time DMSP SSM/I Daily Polar Gridded Brightness Temperatures NISE1COMBONear Real-Time SSM/I EASE-Grid Daily Global Ice Concentration and Snow Extent NSIDC-0024COMBONimbus-7 SMMR Derived Monthly Global Snow Cover and Snow Depth NSIDC-0046COMBONorthern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent Version 2 NSIDC-0042LandDMSP-F8 SSM/I Pathfinder Land Surface Products NSIDC-0002Sea IceDMSP SSM/I Daily and Monthly Polar Gridded Sea Ice Concentrations NSIDC-0007Sea IceNimbus-7 SMMR Polar Gridded Radiances and Sea Ice Concentrations NSIDC-0009Sea IceNimbus-5 ESMR Polar Gridded Sea Ice Concentrations NSIDC-0028Sea IceDMSP-F8 SSM/I Pathfinder Global Level 2 Sea Ice Concentrations NSIDC-0051Sea IceSea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I Passive Microwave Data NSIDC-0079Sea IceBootstrap Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I NSIDC-0081Sea IceNear Real-Time DMSP SSM/I Daily Polar Gridded Sea Ice Concentrations NSIDC-0105Sea IceSnow Melt Onset Over Arctic Sea Ice from SMMR and SSM/I Brightness Temperatures NSIDC-0116Sea IcePolar Pathfinder Daily 25 km EASE-Grid Sea Ice Motion Vectors NSIDC-0192Sea IceSea Ice Trends and Climatologies from SMMR and SSM/I

3. workbook DAAC Product Review 3 The Passive Microwave Data Sets - Summary Brightness Temperatures  Nimbus-5 ESMR, Nimbus-7 SMMR, DMSP SSM/I, NRT SSM/I Combined Products  NRT SSM/I EASE Snow Extent and Ice Concentration (NISE)  Nimbus-7 SMMR Snow Cover and Depth  No. Hem. EASE Weekly Snow Cover and Sea Ice Extent, Ver. 2 Land  DMSP F8 SSM/I Pathfinder Land Surface Products Sea Ice  Concentration: o DMSP SSM/I Polar Gridded, SMMR-SSM/I Polar Gridded, ESMR Polar Gridded, DMSP F8 Global, NRT SSM/I o Trends and Climatologies from SMMR and SSM/I  Other: o Snow Melt over Sea Ice from SMMR and SSM/I T b s o Polar Pathfinder EASE Motion (from SMMR, SSM/I, AVHRR, and buoys)

4. workbook DAAC Product Review 4 Brightness Temperatures, Science Title:  NSIDC-0001, DMSP SSM/I Daily Polar Gridded Tbs  NSIDC-0032, DMSP SSM/I Pathfinder Daily EASE-Grid Tbs  NSIDC-0036, Nimbus-7 SMMR Pathfinder Tbs  NSIDC-0037, Nimbus-7 SMMR Antenna Temperatures  NSIDC-0071, Nimbus-7 SMMR Pathfinder Daily EASE-Grid Tbs  NSIDC-0077, Nimbus-5 ESMR Polar Gridded Tbs  NSIDC-0080, Near Real-Time DMSP SSM/I Daily Polar Gridded Tbs Description: Gridded brightness (antenna) temperatures from passive microwave on polar stereographic grid or EASE-Grid Algorithm: Calibrated, georeferenced on satellite and/or during postprocessing, gridded (12.5 km or 25 km) at NSIDC Science Justification: Provides input to other sea ice products (concentration, snow melt, motion). Model input fields, etc. Quality and Accuracy: Geolocation accuracy to ~5-8 km, Sensor accuracy ~1 K Science Value/Intended Product Use: Inputs into algorithms for physical products, models. As input for sea ice products, which are longest, continuous record of sea ice conditions and have tracked climate variability and trends. Limitations: Low spatial resolution cannot resolve local processes. Daily fields may have errors in select locations.

5. workbook DAAC Product Review 5 Brightness Temperatures, DAAC Title:  NSIDC-0001, DMSP SSM/I Daily Polar Gridded Tbs  NSIDC-0032, DMSP SSM/I Pathfinder Daily EASE-Grid Tbs  NSIDC-0036, Nimbus-7 SMMR Pathfinder Tbs  NSIDC-0037, Nimbus-7 SMMR Antenna Temperatures  NSIDC-0071, Nimbus-7 SMMR Pathfinder Daily EASE-Grid Tbs  NSIDC-0077, Nimbus-5 ESMR Polar Gridded Tbs  NSIDC-0080, Near Real-Time DMSP SSM/I Daily Polar Gridded Tbs Heritage: NSIDC began support of SSMI data in 1983 through research funding from NASA. Justification came from a science study team for use of PM data for sea ice research. (see report authored by R. Thomas, circa 1983) Metrics: See metrics slides Current Involvement/Responsibility: DAAC managed Level and Type of Service: Category/Level1234 Activity - IngestX Activity - DistributionX Maturity - ScienceX Maturity - PreservationX Level of ServiceX

6. workbook DAAC Product Review 6 Combined Products, Science Title:  NISE1, NRT SSM/I EASE-Grid Daily Global Ice Concentration and Snow Extent  NSIDC-0024, Nimbus-7 SMMR Derived Monthly Global Snow Cover and Snow Depth  NSIDC-0046, Northern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent Version 2 Description: Combined snow and ice products over globe or hemisphere, 25 km spatial resolution Algorithm:  NISE and NSIDC-0024 produced from Tbs using established, well-documented algorithms  NSIDC-0046 from NOAA-NESDIS Weekly NH Snow Charts (based on visible imagery) and SMMR-SSM/I sea ice concentrations, regridded to EASE-Grid Science Justification: Provides long-term timeseries of snow and ice Quality and Accuracy: Sea ice average accuracy 5-10% in winter, 10-20% in summer, higher errors near ice edge. Errors of snow cover difficult to assess, passive microwave fields generally agree well with visible imagery, but PM tends to miss shallow snow, wet snow Science Value/Intended Product Use: Large scale trends/variability detection, water resources, model inputs. NISE is an essential input to MODIS processing. Limitations: Cannot resolve local processes; high errors in certain conditions, as described above.

7. workbook DAAC Product Review 7 Combined Products, DAAC Title:  NISE1, NRT SSM/I EASE-Grid Daily Global Ice Concentration and Snow Extent  NSIDC-0024, Nimbus-7 SMMR Derived Monthly Global Snow Cover and Snow Depth  NSIDC-0046, Northern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent Version 2 Heritage: Obtained from PIs Metrics: See metrics slides Current Involvement/Responsibility: DAAC managed Level and Type of Service: Category/Level1234 Activity - IngestXX Activity - DistributionX Maturity - ScienceXXX Maturity - PreservationXXX Level of ServiceX

8. workbook DAAC Product Review 8 Land Products, Science Title:  NSIDC-0042, DMSP-F8 SSM/I Pathfinder Land Surface Products Description: Level 2 and 3 land cover, surface temperature, land use classes, snow cover, and vegetation cover Algorithm: Derived from T b s based on difference thresholds and/or ratios, and statistical regressions Science Justification: Baseline of land surface parameters from F8. Quality and Accuracy: No accuracy info available Science Value/Intended Product Use: Combined with other data can track long-term changes in vegetation, snow, etc. Limitations: Only about one year of data, Aug 1987-Dec 1988 – not useful for interannual variability or climate change. Classification scheme not as detailed as other available algorithms.

9. workbook DAAC Product Review 9 Land Products, DAAC Title:  NSIDC-0042, DMSP-F8 SSM/I Pathfinder Land Surface Products Heritage: Obtained from Marshall Metrics: See metrics slides Current Involvement/Responsibility: DAAC managed Level and Type of Service: Category/Level1234 Activity - IngestX Activity - DistributionX Maturity - ScienceXX Maturity - PreservationXX Level of ServiceX

10. workbook DAAC Product Review 10 Sea Ice Products – Melt and Motion, Science Title:  NSIDC-0105, Snow Melt Onset Over Arctic Sea Ice from SMMR and SSM/I Brightness Temperatures  NSIDC-0116, Polar Pathfinder 25 km EASE-Grid Sea Ice Motion Vectors Description:  Melt onset 25 km polar stereographic fields with date of melt onset for each pixel, 1979- 1998  Sea ice motion is a blended product from passive microwave, visible and infrared imagery, and buoy observations Algorithm:  Melt onset: onset of melt significantly alters PM Tb  Sea ice motion: maximum cross-correlation – matches features in two images separated by some time Science Justification: Melt provides important information on thermodynamics of Arctic; Motion provides important info on dynamics. Science Value/Intended Product Use: Large-scale trends in melt and circulation. Limitations: Errors at specific data points possible due to Tb errors, weather. Surrounding data points should be compared to be sure the data, trends, etc. are consistent.

11. workbook DAAC Product Review 11 Sea Ice Products – Melt and Motion, DAAC Title:  NSIDC-0105, Snow Melt Onset Over Arctic Sea Ice from SMMR and SSM/I Brightness Temperatures  NSIDC-0116, Polar Pathfinder 25 km EASE-Grid Sea Ice Motion Vectors Heritage: Obtained from PIs Metrics: See metrics slides Current Involvement/Responsibility: DAAC managed Level and Type of Service: Category/Level1234 Activity - IngestX Activity - DistributionX Maturity - ScienceXX Maturity - PreservationXX Level of ServiceX

12. workbook DAAC Product Review 12 Sea Ice Products – Concentration, Science Title:  NSIDC-0009, Nimbus-5 EMSR Polar Gridded Sea Ice Concentrations  NSIDC-0002, DMSP SSM/I Daily and Monthly Polar Gridded Sea Ice Concentrations  NSIDC-0007, Nimbus-7 SMMR Polar Gridded Radiances and Sea Ice Concentrations  NSIDC-0028, DMSP-F8, SSM/I Pathfinder Global Level 2 Sea Ice Concentrations  NSIDC-0051 & 0079, NASA Team and Bootstrap Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I  NSIDC-0081, NRT DMSP SSM/I Daily Polar Gridded Sea Ice Concentration Description: Hemispheric sea ice concentration fields on polar stereographic grid (25 km resolution), based on gridded Tb fields Algorithm: NASA Team and Bootstrap algorithms. Both empirically derived from mixing ratios based on pure surface type tiepoints. Algorithms use different formulations and Tb channels. ESMR uses as a single-channel algorithm. Science Justification: Key field in tracking climate change in the Arctic. Quality and Accuracy: average 5-10% winter, 15-20% summer, but errors can be much higher in regions of thin ice, meltponds, and regions of with mixture of three or more ice types Science Value/Intended Product Use: Tracking large-scale variability in sea ice and polar climate. Arctic field indicate a significant long-term downward trend in summer ice extent. Key inputs into climate models, regional process studies, etc. NRT fields provide operational assistance. Limitations: Underestimation in summer, and in thin ice. Daily concentration fields in specific regions may not be reliable. Extent fields more reliable and longer (weekly, monthly) fields more reliable.

13. workbook DAAC Product Review 13 Sea Ice Products – Concentration, DAAC Title:  NSIDC-0009, Nimbus-5 EMSR Polar Gridded Sea Ice Concentrations  NSIDC-0002, DMSP SSM/I Daily and Monthly Polar Gridded Sea Ice Concentrations  NSIDC-0007, Nimbus-7 SMMR Polar Gridded Radiances and Sea Ice Concentrations  NSIDC-0028, DMSP-F8, SSM/I Pathfinder Global Level 2 Sea Ice Concentrations  NSIDC-0051 & 0079, NASA Team and Bootstrap Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I  NSIDC-0081, NRT DMSP SSM/I Daily Polar Gridded Sea Ice Concentration Heritage: GSFC products obtained from PIs. Justification based on transfer of PM data responsibilities from the MSFC DAAC, and through recommendations of the PoDAG (UWG). Metrics: See metrics slides Current Involvement/Responsibility: DAAC managed Level and Type of Service: Category/Level1234 Activity - IngestXX Activity - DistributionXX Maturity - ScienceXX Maturity - PreservationX Level of ServiceX

14. workbook DAAC Product Review 14 GSFC vs. NSIDC Sea Ice Products Update Frequency Time Delay Quality Control Time Period GSFCOnce every 12 months ~ 12 months HighOct 1978 – Dec 2004 NSIDCOnce every 3 months ~ 3 monthsLowJul 1987 - Present NRTOnce per day 1 dayNoneLast 3-6 months

15. workbook DAAC Product Review 15 NASA Team vs. Bootstrap Sea Ice Products FrequenciesProsConsNotes NASA Team 19V, 19H, 37V  PR, GR ratios Independent of temperature Sensitive to layering and thin ice SMMR, SSM/I NASA Team 2 19V, 19H, 37V, 85V, 85H  ratios No layering sensitivity; weather and thin ice correction No data before 1992 SSM/I, AMSR-E Bootstrap 19V, 37V or 37V, 37H No sensitivity to layering Temperature dependence, seasonal tiepoints SSMR, SSM/I, AMSR-E Adapted from slide by T. Markus, 2004