Remote Sensing of the Environment

Course Information

Courses and exams
Prof	Smets Benoît
Courses	Lectures and practicals
Examination	50% report 20% practical exam open book 30% oral exam (no preparation)
Background
Credits	3
When?	2nd term
ECTS	KU Leuven VUB

This course is new since 2022. Smets is very friendly during the exam!

2025

June

18/06/2025

Practical exam:

1. GEE-script of the UN on flood detection using RADAR imagery for two dates. ( / 12)
   1. What is the extent of the flood, in m² ? ( / 1)
   2. How many people were affected? ( / 1)
   3. Why is there an underestimation of the people affected? ( / 2)
   4. Which polarization technique is best for floods, VH or VV? ( / 2)
   5. Cite at least two limitations to SAR based flood detection. ( / 2)
   6. What names of the dimensions of a SAR image? ( / 1)
2. NHI-tool for the Erta Ale
   1. What are the two peak dates of hotspot detection? ( / 1)
   2. How can we compare hotspot pixels of image with different resolutions? Create a formula and explain. ( / 2)
   3. What is the peak heat emission and on what date, include the unit. ( / 1)
   4. Describe the difference between the measures VRP/FRP and the hotspot pixel count, include the units ( / 4)
3. Interferograms
   1. What is the difference between the two images' acquisition geometry? ( / 1)
   2. What does LOS mean? ( / 1)
   3. Why are the fringes in the right image inverted in comparison to the one on the left? ( / 2)
   4. Why are there areas with no fringes or color? ( / 2)

Oral/Theory:

1. Definitions (you needed to explain three random ones)
   1. Nadir
   2. SAR
   3. Photogrammetry
   4. BTD
   5. Sentinel1
   6. Azimuth & range
   7. ESA
   8. GOES17
   9. Sentinel3
   10. Phase unwrapping
   11. SfM
   12. Sentinel2-MSI
   13. Sentinel3 SLSTR
   14. SAR Coherence
   15. Sentinel5P TROPOMI
2. Methods
   1. SAR - floods
   2. BTD
   3. DIC
   4. Hotspot detection
   5. SfM/MVS
3. Image
   1. Volcanic ash clouds
   2. Notre Dame tie points
   3. Lava flow & DIC
   4. Landslides & DIC
   5. Measured, nodelled and residual ground deformation
   6. dInSAR

10/06/2025

Practical exam:

1. GEE-script of the UN on flood detection using RADAR imagery.
   1. What is the extent of the flood? How many people were affected? (These variables are included in the script) Why is there an underestimation of the people affected?
   2. Which polarization technique is best for floods (VH or HH)?
   3. What are the dimensions of a SAR image?
   4. What are disadvantages of flood detection using RADAR?
2. NHI-tool
   1. What are the two peak dates of hotspot detection?
   2. How can we compare hotspot pixels of image with different resolutions?
   3. What is the peak heat emission and on what date, include the unit
   4. Describe the difference between VRP/FRP and the hotspot pixel
3. Interferograms
   1. What is the difference between the two images?
   2. What does LOS mean
   3. Why are the fringes in the right image inverted in comparison to the one on the left?
   4. Why are there areas with no fringes or color?

Definitions:

1. Nadir
2. SAR
3. Sentinel-3 (SLSTR)
4. DIC
5. SAR coherence
6. Sentinel-5 (TROPOMI)
7. BTD
8. Photogrammetry
9. Sentinel-1

Methods:

1. SfM-VSM photogrammetry
2. Thermal hotspot detection
3. Digital Image Correlation

Images:

1. DIC of a lava flow
2. Tie points/key points (Notre Dame image)
3. Foreshortening/shadow/overlap
4. Plot with B4 and B12 marked. Used to calculate hotspots. Wiens displacement law

2023

June

20/06/2023

Definitions (3 pp):

1. SAR Coherence
2. DIC
3. Sentinel-5P (Tropomi)
4. Interior orientation
5. FRP
6. Landat 8 (OLI)
7. Nadir
8. SAR
9. Sentinel-2 (SLSTR)
10. BTD

Explain image (1pp):

• Image of passive and active sensor + atmospheric distrubances
• Image of corner reflextion
• Image of  distortion and residual map
• Image of clouds and ash (BTD)

Explain Method (1pp):

• SAR Interferometry
• Thermal hotspot detection
• InSAR

2022

You have to explain 3 definitions, one image and one method per student by drawing cards. The examples below were all asked during the oral exam:

Definitions (per 3):

1. Azimuth and range direction
2. ESA
3. GOES-17

1. BTD
2. Photogrammetry
3. Sentinel-1

1. Nadir
2. SAR
3. Sentinel3-SLSTR

1. Interferrometric phase unwrapping
2. SfM
3. Sentinel-2

Explain image:

• Image of DEM and dense point cloud of volcano
• Image of atmospheric disturbance
• Image of digital image correlation (+can you see vertical displacement? No)
• Image of earth radiation budget
• Image of Notre dame and lines (image matching)

Explain method:

• Hotspot detection (Wien's law and NTI)
• SfM and MVS (+ difference tie point and point in sparse point cloud)
• Volcanic ash detection
• SAR inferrometry