Core geogg141: Principles and Practice of Remote Sensing

Format:

The course is based upon lectures, with occasional seminars provided by outside speakers from industry, government etc.

At the end of the course students should:

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  Have knowledge and understanding of the basic concepts, principles and applications of remote sensing.
  
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  Be able to derive solutions to given quantitative problems particularly related to geometric principles, EM radiation, LIDAR and RADAR systems
  
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  Have an understanding of the trade-offs in sensor design, orbit, resolution etc. required for a range of applications
  
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  Have an understanding of the propagation of radiation transfer in vegetation, and be able to explain the problem, and propose mathematical solutions
  

This module runs in Term 1

Contact time = 34 hours

DB = Dietmar Backes (dietmar@cege.ucl.ac.uk)

JI = Jon Iliffe (jiliffe@cege.ucl.ac.uk )
Examinations

The examination will be a combination of essay-type and problem-solving questions. Candidates will answer three questions on this part of the course from a choice of four in 2 hours. The PPRS MSc module (CEGE046) has run with different module codes in the past, so the past papers are: CEGE046 (2008-2010); GEOMG017 (2007-8), GEOGRSC1 (2005-6), GEOGGR01 (2007 referred/deferred paper). Past exam papers are kept in the library (http://exam-papers.ucl.ac.uk/SocHist/Geog/).

All teaching notes are available from the course webpage and moodle.

Aronoff, S., et. al. (2005), Remote Sensing for GIS Managers. ESRI Press, Redlands.

Iliffe, J., Lott, R. (2008), Datums and Map Projections: for Remote Sensing, GIS and Surveying. Whittles Publishing London.

Konecny, G., (2002). Remote Sensing, Photogrammetry and Geographic Information Systems. Taylor and Francis, London.

Zhilin, L., Chen, J. & Baltsavias, E., (2008), Advances in Photogrammetry, Remote Sensing and Spatial Information Sciences. CRC Press London,

Mikhail, E., Bethel, J., McGlone, J., (2001), Introduction to modern Photogrammetry. John Wiley & Sons New York.

Campbell, J. B. (2007) Introduction to Remote Sensing (2nd Ed), London, Taylor and Francis, 4^th edn. (a good general textbook covering theory with a little bit on image interpretation).

Jensen, John R. (2006) Remote Sensing of the Environment: an Earth Resources Perspective, Hall and Prentice, New Jersey, 2^nd ed. (an excellent, slightly more advanced textbook covering theory and applications but not image processing. A solid investment).

Jones, H. and Vaughan, R. (2010, paperback) Remote Sensing of Vegetation: Principles, Techniques, and Applications, OUP, Oxford. (A graduate-level textbook covering theory and applications related to vegetation – more specialized but a very good primer in the field).

Liang, S. (2004) Quantitative Remote Sensing of Land Surfaces, Wiley-Blackwell (an excellent, advanced textbook covering radiation transfer, theory and algorithms. Expensive, so try the library).

Lillesand, T., Kiefer, R. and Chipman, J. (2004) Remote Sensing and Image Interpretation. John Wiley and Sons, NY, 5^th ed.. (Good general textbook with image processing as well).

Monteith, J. L and Unsworth, M. H. (1990) Principles of Environmental Physics, Edward Arnold: Routledge, Chapman and Hall, NY, 2^nd ed. (an excellent book covering basic physics – lots of useful parts here on radiation, surface energy budgets, modelling etc. – a real gem).

Purkis, S. J. and Klemas, V. V. (2011) Remote Sensing and Global Environmental Change, Wiley-Blackwell (a good account of various remote sensing applications, strong on ocean and coral reefs).

Rees, W. G. (2001, 2^nd ed.). Physical Principles of Remote Sensing, Cambridge Univ. Press. (Good general textbook).

Warner, T. A., Nellis, M. D. and Foody, G. M. eds. (2009) The SAGE Handbook of Remote Sensing (Hardcover). Limited depth, but very wide-ranging – excellent reference book.

http://rst.gsfc.nasa.gov/Front/tofc.html

http://mercator.upc.es/nicktutorial/TofC/table.html

http://earth.esa.int/applications/data_util/SARDOCS/spaceborne/Radar_Courses/

http://www.ccrs.nrcan.gc.ca/ccrs/learn/tutorials/fundam/fundam_e.html

Other resources

NASA www.nasa.gov

European Space Agency www.esa.int

NOAA www.noaa.gov

Remote sensing and Photogrammetry Society UK www.rspsoc.org

Remote Sensing of the Environment (via Science Direct from within UCL): http://www.sciencedirect.com/science?_ob=JournalURL&_cdi=5824&_auth=y&_acct=C000010182&_version=1&_urlVersion=0&_userid=125795&md5;=5a4f9b8f79baba2ae1896ddabe172179

International Journal of Remote Sensing: http://www.tandf.co.uk/journals/titles/01431161.asp

IEEE Transactions on Geoscience and Remote Sensing: http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?puNumber=36

Housekeeping

What is remote sensing and why do we do it?

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  Definitions of remote sensing
  
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  Examples and applications
  
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  Introduction to process
  
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  Collection of signal
  
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  Interpretation into information
  
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  Experience of students?
  

Introduction to some terms and concepts

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  EM Radiation
  
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  Solar properties
  
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  Interaction with atmosphere
  
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  Interaction with surface
  
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  Resolution
  
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  Spatial
  
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  Spectral
  
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  Temporal
  
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  Angular
  
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  Radiometric
  

The remote sensing process

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  Instrument design
  
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  Mission
  

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  Information collection and processing
  

Introduction to EM spectrum

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  Conduction, convection, radiation (JJ29)
  

Wave model of EM radiation

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  Properties of EM wave (JJ30)
  
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  Concepts of wave velocity, wavelength, period etc. (JJ31)
  

Solar radiation

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  Concept of blackbody (MU25)
  
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  Kirchoff's Law (JJ250)
  
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  Radiant energy of sun/Earth (thermal emission)
  
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  Stefan-Boltzmann law (MU25/JJ247)
  
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  Wien's displacement law (MU25)
  
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  Planck's law (MU26)
  
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  Solar constant (MU36)
  
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  Implications of en. distribution for EO
  
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  Calculation of energy between given wavelengths
  
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  Implications for evolution of the eye, chlorophyll pigments etc. etc.
  

Particle model of EM radiation

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  Photon energy (JJ35)
  
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  Photoelectric effect (JJ36)
  
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  Quantum energy and unit (MU27/JJ37)
  
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  Atomic energy levels (JJ38)
  

Radiation geometry and interactions

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  Radiant flux, and radiant flux density (MU28)
  
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  Radiance/Irradiance, Exitance, Emittance (MU28/MU31)
  
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  Flux from a point source and from a plane source (MU29/MU30)
  
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  Cosine law for emission & absorption, Lambert's Cosine Law (MU29/MU30)
  

Interaction with the atmosphere

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  Refraction (index of etc.), Snell's Law (JJ39)
  
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  Scattering
  
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  Rayleigh, Mie, Non-selective (JJ41)
  
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  Absorption (JJ42/MU39) and atmospheric windows
  
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  Absorption (and scattering at the surface)
  
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  Examples of vegetation, soil, snow spectra
  
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  Spectral features and information
  
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  Sun/Earth geometry, direct and diffuse radiation (MU40-42)
  

Interaction of radiation with the surface

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  Reflectance, specular, diffuse etc.
  
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  BRDF
  
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  Hemispherical reflectance, transmittance, absorptance
  
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  Albedo
  
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  Surface spectra
  

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  Spectral features and information
  

Resolution: concepts (JJ12-17)

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  Spatial
  
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  Spectral
  
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  Temporal
  
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  Angular
  
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  Radiometric
  
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  Time-resolved signals
  
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  RADAR, LiDAR (sonar)
  

Spatial:

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  High v Med/Moderate v Low
  
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  E.g. IKONOS, MODIS/AVHRR, MSG
  
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  IFOV and pixel size
  

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  GRE/GRD/GSD (LK 334)
  

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  Point spread function
  
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  What's in a pixel? (Cracknell, A. P., IJRS, 1998, 19(11), 2025-2047).
  
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  Mixed pixel, continuous v. Discrete, generalisation
  

Spectral

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  Wavelength considerations
  

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  Optical
  
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  Photography, scanning sensors, LiDAR et.
  
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  Microwave (active/passive)
  
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  RADAR
  
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  Thermal
  
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  Atmospheric sounders
  

Temporal/Angular

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  Orbits
  

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  Kepler's Laws
  
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  Orbital period, altitude
  
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  Polar, equatorial and Geostationary (LK 397-9; JJ187-9 and 201)
  
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  Advantages/disadvantages of various orbits
  
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  Coverage of surface
  
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  Solar crossing time/elevation
  

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  Broad swath instruments
  
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  AVHRR/POLDER/MODIS etc.
  
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  v Narrow swath
  
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  Landsat ETM+, IKONOS, MISR etc.
  

Radiometric

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  Precision v accuracy
  
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  Digital v analogue
  
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  Signal to noise
  

Processing stages

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  Transmission
  
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  Storage and dissemination
  
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  Ground segment
  
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  Overview of pre-processing stages
  
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  Geometric, radiometric, atmospheric correction
  

Multi/hyperspectral scanners

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  Heritage
  
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  Landsat, AVHRR (NOAA), EOS/NPOESS (NASA), ESA (Envisat, Explors etc.)
  
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  Discrete detectors and scanning mirrors (JJ183)
  
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  Pushbroom/whiskbroom linear arrays (JJ184)
  
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  Across track scanning (LK 331, 337)
  
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  Digital frame camera area arrays
  
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  Detector types (CCD, LK 336)
  
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  Hyperspectral area arrays
  
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  Examples of the different systems
  

LiDAR

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  Vegetation
  
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  First/last pass (discrete return), waveform
  

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  Principles of lidar measurement
  
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  Information content
  

Radiative approach

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  RT theory at optical wavelengthgs
  
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  Wave propagation, polarisation
  
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  Tools for developing RT
  
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  Canopy scattering models
  
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  Scalar RT equation
  
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  Extinction coefficient, Beer’s Law
  
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  Simplifications for vegetation canopies
  
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  Recollision probability theory
  

RADAR: Definitions

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  SLAR, SAR, IfSAR
  
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  Principles
  
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  Ranging and imaging
  
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  Geometry
  
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  Wavelengths
  
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  SAR principles
  
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  Resolution
  
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  Azimuth, range
  
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  ERS1 & 2 examples
  

Radiometric effects

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  Speckle
  
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  RADAR equation
  

Geometric effects

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  Shadow
  
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  Foreshortening
  
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  Layover
  

Surface interactions

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  Moisture
  
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  Types of interaction
  

The RADAR equation

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  Measurable quantities
  
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  Calibration
  

Interferometric SAR (InSAR)

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  Principles
  
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  Phase information
  
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  Coherence
  
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  Phase unwrapping
  
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  Interferograms, fringes, DEMs
  
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  Sources
  
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  Problems
  
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  Geomtetry
  
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  Decoherence
  
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  Accuracy
  
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  Differential InSAR