Mission Requirements

The Level 1 Science Requirements flow down to lower-level science requirements. These Level 2 requirements expand to specific science measurements within each major discipline. While there is formal language associated with each of the Level 2 science requirements, they are most easily understood in tabular form. The following tables are grouped by discipline.

Solid Earth Science Level 2 Requirements

Attribute	Secular Deformation (658)	Co-Seismic Deformation (660)	Transient Deformation (663)
Measurement	Spatially averaged relative velocities in two dimensions	Point-to-point relative displacements in two dimensions	Point-to-point relative displacements in two dimensions
Method	Interferometry, Speckle tracking	Interferometry, Speckle tracking	Interferometry, Speckle tracking
Duration	3 years	3 years	Episodic over mission, depending on science target
Product resolution	100 m; smoothed according to distance scale L	100 m	100 m
Accuracy	2 mm/yr or better, 0.1 km < L < 50 km, over > 70% of coverage areas	4 (1+L1/2) mm or better, 0.1 km < L < 50 km, over > 70% of coverage areas	3 (1+L1/2) mm or better, 0.1 km < L < 50 km, over > 70% of ~2,000 targeted sites
Sampling	One estimate over 3 years, two directions	4 times per year to guarantee capture of any earthquake on land before surface changes too greatly	Every 12-days, two directions
Coverage	Land areas predicted to move faster than 1 mm/yr	All land, as earthquake locations are unknown a priori	Post-seismic events, volcanoes, ground-water, gas, hydrocarbon reservoirs, landslide-prone
Response latency	N/A	24 hr tasking, 5 hr data delivery Best effort basis on event	24/5 Best effort basis on event

Cryosphere Science Level 2 Requirements

Attribute	Ice Sheets and Glaciers Velocity Slow Deformation (667)	Ice Sheets and Glaciers Velocity Fast Deformation (668)	Ice Sheet Time-Varying Velocity (738)
Measurement	Point-to-point displacements in two dimensions	Point-to-point displacements in two dimensions	Point-to-point relative horizontal displacements
Method	Interferometry, Speckle tracking	Interferometry, Speckle tracking	Interferometry, Speckle tracking
Duration	3 years	3 years	3 years
Product resolution	100 m	250 m	500 m
Accuracy	3% of the horizontal velocity magnitude plus 1 m/yr, or better, over > 90% of coverage areas	3% of the horizontal velocity magnitude plus 5 m/yr, or better, over > 90% of coverage areas	3% of the horizontal velocity magnitude plus 10 m/yr, or better, over > 80% of coverage areas
Sampling	Each cold season, two directions	Each cold season, two directions	Every 12-days, two directions
Coverage	Areas moving slower than 50 m/yr of both poles and glaciers and icecaps	Areas moving faster than 50 m/yr of both poles	Outlet glaciers, or other areas of seasonal change
Response latency	N/A	N/A	24/5 Best effort basis on event

Attribute	Permafrost Displacement (671)	Grounding Line Vertical Displacement (445)	Sea Ice Velocity (670)
Measurement	Spatially averaged relative velocities in two dimensions	Point-to-point relative displacements in two dimensions	Point-to-point relative horizontal displacements
Method	Interferometry	Interferometry	Backscatter image feature tracking
Duration	3 years	3 years	3 years
Product resolution	100 m	100 m	Gridded at 5 km
Accuracy	10 mm or better, over > 80% of coverage areas	100 mm or better, over 95% coverage areas annually over 50% coverage areas monthly	100 m / day, over 70% of coverage area
Sampling	In snow-free months sufficient to meet accuracy (semi-monthly)	Monthly	Every 3 days
Coverage	Targeted priority regions in Alaska and Canada	Greenland and Antarctic coastal zones	Seasonally-adjusted Arctic and Antarctic sea ice cover
Response latency	N/A	24 hour tasking, 5 hour data delivery Best effort basis on event	24/5 Best effort basis on event

Ecosystems Science Level 2 Requirements

Attribute	Biomass (673)	Disturbance (675)	Inundation (677)	Crop Area (679)
Measurement	Biomass	Areal extent	Areal extent	Areal extent
Method	Polarimetric backscatter to biomass	Polarimetric backscatter temporal change	Polarimetric backscatter contrast	Polarimetric backscatter contrast and temporal change
Duration	3 years	3 years	3 years	3 years
Product resolution	100 m	100 m	100 m	100 m
Accuracy	20 Mg/ha or better where biomass is < 100 Mg/ha, over 80% of coverage areas	80% or better classification accuracy where canopy cover changes by > 50%	80% or better classification accuracy	80% or better classification accuracy
Sampling	Annual	Annual	Seasonal, sampled every 12 days to track beginning and end of flooding events	Quarterly; sampled every 12 days to track beginning and end of growing season
Coverage	Global areas of woody biomass	Global areas of woody biomass	Global inland and coastal wetlands	Global agricultural areas
Response latency	N/A	24/5 Best effort basis on event	24/5 Best effort basis on event	N/A