LECTURE & WORKSHOP

Terrain Mapping & Radar RS

March 19, 2026 | Classroom

Sessions

10:00 - 11:00 Terrain Mapping
11:00 - 12:00 Radar RS & SAR Applications
14:00 - 16:00 GEE-Elevation Modeling

📚 Required Readings

Digital Elevation Models

DEMs, DSMs, DTMs, and terrain derivatives.

📖 RS eBook - Chapter 11
Radar Remote Sensing

SAR principles, polarimetry, and InSAR applications.

📖 RS eBook - Chapter 12
Terrain Analysis in GEE

Slope, aspect, hillshade, and watershed delineation.

📖 RS eBook - Chapter 13

📝 Key Concepts for the Exam

Active vs. Passive Sensors
Optical (Passive)

Relies on reflected sunlight. Blocked by clouds. Daytime only. Measures surface reflectance. Platforms: Landsat, Sentinel-2, MODIS.

SAR (Active)

Transmits own microwave pulses. Penetrates clouds, rain, smoke. Day and night. Measures surface roughness and moisture. Platforms: Sentinel-1, ALOS PALSAR.

InSAR and SAR Polarization
  • InSAR (Interferometric SAR): Compares the phase difference between two SAR acquisitions to detect millimeter-scale surface deformation (subsidence, volcanic uplift, earthquake damage).
  • Co-polarized (HH, VV): Sensitive to surface roughness. Used for soil moisture and water detection.
  • Cross-polarized (HV, VH): Sensitive to volume scattering (forest canopy structure). Valuable for biomass estimation.
Elevation Models
  • DEM (Digital Elevation Model): Generic term for any elevation raster. Represents bare-earth or surface height.
  • DSM (Digital Surface Model): Includes buildings, trees, and other structures above the ground.
  • DTM (Digital Terrain Model): Represents the bare earth surface only, with structures removed.
  • Hillshade: A visualization technique where the analyst controls azimuth and altitude of a simulated light source. Changing illumination parameters completely alters the terrain narrative (GIS as Art).

Assessment

Final Exam Prep

Terrain and Radar concepts are core components of the module exam.

Assessed