Landsat H (8)Landsat H (8) Long-Term Acquisition Long-Term Acquisition

PlanPlan

Samuel N. Goward – UMDSamuel N. Goward – UMD

Darrel L. Williams – Darrel L. Williams – NASA/GSFCNASA/GSFC

Andrew Macatee - UMDAndrew Macatee - UMD

L7 – LTAPL7 – LTAP

1993 Beginning for 1998 Launch1993 Beginning for 1998 Launch– Finished 1999Finished 1999

Validation 2000-2002Validation 2000-2002– SLC failureSLC failure

Validation Lessons Learned Validation Lessons Learned – LTAP-5, LTAP-7, LTAP-8LTAP-5, LTAP-7, LTAP-8

Validation Outcomes Summary

SeasonalitySeasonality– Good global coverage on quarterly basisGood global coverage on quarterly basis– Regional coverage needs adjustmentRegional coverage needs adjustment

Excessive deserts and winter high latitudesExcessive deserts and winter high latitudes Excessive tropical cloud coverExcessive tropical cloud cover Not enough boreal forest growing seasonNot enough boreal forest growing season

RadiometryRadiometry•Fourth generation gain change Fourth generation gain change approachapproach•Change solar zenith angle Change solar zenith angle threshold to 75º from threshold to 75º from 85º in Northern Hemisphere85º in Northern Hemisphere

Cloud AvoidanceCloud Avoidance•25% reduced cloud 25% reduced cloud contamination in archive contamination in archive imageryimagery•ACCA within 10%, 95% of the ACCA within 10%, 95% of the timetime•NOAA NCEP predicts and ACCA NOAA NCEP predicts and ACCA agree best agree best at high (>80%) and low (<20%) at high (>80%) and low (<20%) cloud covercloud cover•Problems at land/water margins Problems at land/water margins (e.g., coastal regions)(e.g., coastal regions)

Potential LTAP Potential LTAP EnhancementsEnhancements

Improve LTAP coverageImprove LTAP coverage– Reduced desert and winter acquisitionsReduced desert and winter acquisitions– Focused boreal and tropical forest acquisitionsFocused boreal and tropical forest acquisitions– Consideration of image composite approachesConsideration of image composite approaches– Conversion of niches to campaigns Conversion of niches to campaigns

Incorporate continuous variable seasonality (NDVI)Incorporate continuous variable seasonality (NDVI)– Better use of LTAP decision makingBetter use of LTAP decision making

Include land mask for ACCA assessment, possibly Include land mask for ACCA assessment, possibly for cloud predict applicationfor cloud predict application

Consider Low-gain-only operationsConsider Low-gain-only operations– Gain changes more of a problem than a solutionGain changes more of a problem than a solution

Cloud Contamination Cloud Contamination (L7 16-Day Temporal Repeat – Washington DC region, (L7 16-Day Temporal Repeat – Washington DC region,

2000)2000)

May 11 May 27 June 12

June 28

July 14 July 30

Cloud Contamination Cloud Contamination (L7 16-Day Temporal Repeat – Oregon region, (L7 16-Day Temporal Repeat – Oregon region,

2000)2000)May 19 June 04 June 20

Aug 07July 22July 06