PHY2505 - Lecture 11

1. PHY2505 - Lecture 11 Principles of remote sensing With thanks to Prof. K. Strong for lecture material Selected figures from: “Remote Sensing of the Lower Atmosphere” Graeme L. Stephens, Oxford University Press (1994) ISBN 019-5081889

2. What do we mean by remote sensing? Remote sensing definition

3. What do we mean by remote sensing? a means of obtaining information about an object or medium without coming into contact with it Remote sensing definition

4. What do we mean by remote sensing? a means of obtaining information about an object or medium without coming into contact with it General: The acquisition and measurement of data/information on some property(ies) of a phenomenon, object, or material by a recording device not in physical, intimate contact with the feature(s) under surveillance; techniques involve amassing knowledge pertinent to environments by measuring force fields, electromagnetic radiation, or acoustic energy employing cameras, radiometers and scanners, lasers, radio frequency receivers, radar systems, sonar, thermal devices, seismographs, magnetometers, gravimeters, scintillometers, and other instruments. Remote sensing definition

5. Remote sensing is an INDIRECT METHOD that requires the solution of the inverse problem: In simple terms: The inverse problem

6. There is always the niggling doubt that you are actually measuring what you think you are and it is related to the thing you want to measure in the way you think! In fact nearly all measurements are done in this way, but only in some fields is the possibility of error large enough to account for. The inverse problem

7. Fundamental obstacles in the inverse problem What are the three main problems associated with the inverse problem?

8. Fundamental obstacles in the inverse problem

9. Fundamental problems with the inverse problem We will look at the inverseproblem and weighting functions for particular measurement scenarios later, FIRST…

10. Classification of remote sensing methods Source of radiation Type of measurements Spectral region

11. Active & Passive methods Source of radiation Type of measurements Spectral region

12. Passive methods

13. Active methods

14. Types of remote sensing methods

15. REMOTE SENSING FAMILY TREE Active methods

16. REMOTE SENSING FAMILY TREE Active methods

17. Passive Imaging systems

18. Four passive imaging techniques Eg. The Mars Imager for Cloud and Aerosol

19. Four passive imaging techniques

20. Four passive imaging techniques

21. OPTO-MECHANICAL SCANNERS WHISKBROOM PUSHBROOM

22. Four passive imaging techniques

23. REMOTE SENSING FAMILY TREE Active methods

24. Passive non-imaging methods

25. REMOTE SENSING FAMILY TREE Active methods

26. Passive sounding methods

27. Passive sounding methods: radiometers

28. Passive sounding methods: spectrometers

29. Passive sounding methods: spectrometers

30. Passive sounding methods: interferometers ABB BOMEM ACE-FTS

31. REMOTE SENSING FAMILY TREE Active methods

32. Active methods

33. Active imaging methods

34. Active imaging methods: SAR

35. Active non-imaging methods: LASER

36. Active non-imaging methods: RADAR

37. REMOTE SENSING FAMILY TREE Active methods

38. Active sounding methods

39. Active sounding methods: RADAR

40. Active sounding methods: LIDAR

41. Active sounding methods: LITE