CORE GEOGG141: Principles and Practice of Remote Sensing (15 credits) Term 1 (2011) Note the sessions are TBC as of June 2011 Staff: Mat Disney (convenor), Jon Iliffe, Dietmar Backes Dr. M. Disney, room 113 Pearson Building, tel. 7679 0592 (x30592) mdisney@geog.ucl.ac.uk Course web page http://www2.geog.ucl.ac.uk/~mdisney/teaching/GEOGG141/GEOGG141.html Aims: To provide knowledge and understanding of the basic concepts, principles and applications of remote sensing, particularly the geometric and radiometric principles; To provide examples of applications of principles to a variety of topics in remote sensing, particularly related to data collection, radiation, resolution, sampling, mission choices. To introduce the principles of the radiative transfer problem in heterogeneous media, as an example application of fundamental principles. To provide some background to remote sensing organizations and policy through occasional seminars. Content: The module will provide an introduction to the basic concepts and principles of remote sensing. It will include 3 components: i) geometric principles of remote sensing: geodetic principles and datums, reference systems, mapping projections distortions and transformations; data acquisition methods; ii) radiometric principles remote sensing: electromagnetic radiation; basic laws of electromagnetic radiation; absorption, reflection and emission; atmospheric effects; radiation interactions with the surface, fundamentals of radiative transfer in heterogeneous media (vegetation); orbits; spatial, spectral, temporal, angular and radiometric resolution; data pre-processing; scanners; iii) timeresolved remote sensing including: RADAR principles; the RADAR equation; RADAR resolution; phase information and SAR interferometry; LIDAR remote sensing, the LIDAR equation and applications. Introduction to geodetic principles and datums (JI) Data acquisition and positioning (DB) 3D mapping and imaging (DB) Introduction to remote sensing (MD) Radiation principles, EM spectrum, blackbody (MD) EM spectrum terms, definitions and concepts (MD) Radiative transfer (MD) Spatial, spectral resolution and sampling (MD) Pre-processing chain, ground segment, radiometric resolution, scanners (MD) LIDAR remote sensing (MD) RADAR remote sensing I: principles (MD) RADAR remote sensing II: interferometric SAR (MD) Assessment: 3 hour seen examination, which takes place at the start of Term 2. Format: The course is based upon lectures, with occasional seminars provided by outside speakers from industry, government etc. Learning Outcomes: At the end of the course students should: Have knowledge and understanding of the basic concepts, principles and applications of remote sensing. Be able to derive solutions to given quantitative problems particularly related to geometric principles, EM radiation, LIDAR and RADAR systems Have an understanding of the trade-offs in sensor design, orbit, resolution etc. required for a range of applications Have an understanding of the propagation of radiation transfer in vegetation, and be able to explain the problem, and propose mathematical solutions Class schedule: This module runs in Term 1 Sessions Week 1 2 Date Day/Time Duration Class Room 07/10 Fri 11-13 2 hrs Introduction to mapping methods 2 07/10 Fri 14-16 2 hrs Mapping foundations I 3 14/10 Fri 11-13 2 hrs Mapping foundations II 3 14/10 Fri 14-16 2 hrs Data Acquisition 1: GNSS 4 21/10 Fri 11-13 2 hrs Mapping foundations: III 4 21/10 Fri 14-16 2 hrs Data Acquisition 2: 3D mapping 5 5 6 6 7 7 8 8 9 9 10 28/10 Fri 11-13 Introduction, Radiation I 04/10 Fri 11-13 2 hrs 2 hrs 2 hrs 11/11 Fri 11-13 Fri 14-16 25/11 10 11 11 12 12 Lecturer DB/JI Radiation II Gordon St [25] D103 Malet Pl Eng 1.02 Gordon St [25] D103 Malet Pl Eng 1.02 Gordon St [25] D103 Malet Pl Eng 1.02 PBG07 PBG07 PBG07 2 hrs 2 hrs 2 hrs Radiative transfer I Radiative transfer II Spatial, spectral resolution/sampling PBG07 PBG07 PBG07 MD MD MD Fri 11-13 2 hrs Angular and temporal resolution/sampling PBG07 MD 02/12 Fri 11-13 2 hrs PB110 MD 02/12 09/12 Fri 14-16 Fri 11-13 2 hrs 2 hrs Pre-processing, ground segment, scanning LIDAR remote sensing RADAR remote sensing 1 PB110 PBG07 MD MD 16/12 16/12 Fri 11-13 Fri 14-16 2 hrs 2 hrs RADAR remote sensing 2 RADAR III + revision PBG07 PB110 MD MD 18/11 Contact time = 34 hours JI JI DB JI DB MD MD MD Key contacts: MD = Mat Disney (mdisney@geog.ucl.ac.uk) 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/). NOTE: The course has been modified for the 2011 academic year and now contains the radiative transfer elements of the Vegetation Science option module from previous years (CEGEG065). The course also changed significantly in 2005 and 2007 so you should ignore Q4 on the 2006 GEOGRSC1 paper, Q1 on the 2005 GEOGRSC1 paper, and Q3 on the 2007 GEOGGR01 paper. Course material All teaching notes are available from the course webpage and moodle. Books Mapping principles 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. Remote Sensing principles Campbell, J. B. (2007) Introduction to Remote Sensing (2nd Ed), London, Taylor and Francis, 4th 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, 2nd 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, 5th 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, 2nd 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, WileyBlackwell (a good account of various remote sensing applications, strong on ocean and coral reefs). Rees, W. G. (2001, 2nd 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. Web resources Tutorials 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 Journals 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 Detailed outline of Remote Sensing component MU = Monteith and Unsworth (1990) JJ = Jensen, J. (2006) LK = Lillesand & Kiefer (2004) Introduction to remote sensing principles & Radiation I Housekeeping What is remote sensing and why do we do it? Definitions of remote sensing Examples and applications Introduction to process Collection of signal Interpretation into information Experience of students? Introduction to some terms and concepts EM Radiation Solar properties Interaction with atmosphere Interaction with surface Resolution Spatial Spectral Temporal Angular Radiometric The remote sensing process Instrument design Mission Information collection and processing Introduction to EM spectrum Conduction, convection, radiation (JJ29) Wave model of EM radiation Properties of EM wave (JJ30) Concepts of wave velocity, wavelength, period etc. (JJ31) Solar radiation Concept of blackbody (MU25) Kirchoff's Law (JJ250) Radiant energy of sun/Earth (thermal emission) Stefan-Boltzmann law (MU25/JJ247) Wien's displacement law (MU25) Planck's law (MU26) Solar constant (MU36) Implications of en. distribution for EO Calculation of energy between given wavelengths Implications for evolution of the eye, chlorophyll pigments etc. etc. Radiation principles II Particle model of EM radiation Photon energy (JJ35) Photoelectric effect (JJ36) Quantum energy and unit (MU27/JJ37) Atomic energy levels (JJ38) Radiation geometry and interactions Radiant flux, and radiant flux density (MU28) Radiance/Irradiance, Exitance, Emittance (MU28/MU31) Flux from a point source and from a plane source (MU29/MU30) Cosine law for emission & absorption, Lambert's Cosine Law (MU29/MU30) Interaction with the atmosphere Refraction (index of etc.), Snell's Law (JJ39) Scattering Rayleigh, Mie, Non-selective (JJ41) Absorption (JJ42/MU39) and atmospheric windows Absorption (and scattering at the surface) Examples of vegetation, soil, snow spectra Spectral features and information Sun/Earth geometry, direct and diffuse radiation (MU40-42) Interaction of radiation with the surface Reflectance, specular, diffuse etc. BRDF Hemispherical reflectance, transmittance, absorptance Albedo Surface spectra Spectral features and information Data acquisition and sensor design considerations (lectures 4-7) Resolution: concepts (JJ12-17) Spatial Spectral Temporal Angular Radiometric Time-resolved signals RADAR, LiDAR (sonar) Spatial: High v Med/Moderate v Low E.g. IKONOS, MODIS/AVHRR, MSG IFOV and pixel size GRE/GRD/GSD (LK 334) Point spread function What's in a pixel? (Cracknell, A. P., IJRS, 1998, 19(11), 2025-2047). Mixed pixel, continuous v. Discrete, generalisation Spectral Wavelength considerations Optical Photography, scanning sensors, LiDAR et. Microwave (active/passive) RADAR Thermal Atmospheric sounders Temporal/Angular Orbits Kepler's Laws Orbital period, altitude Polar, equatorial and Geostationary (LK 397-9; JJ187-9 and 201) Advantages/disadvantages of various orbits Coverage of surface Solar crossing time/elevation Broad swath instruments AVHRR/POLDER/MODIS etc. v Narrow swath Landsat ETM+, IKONOS, MISR etc. Radiometric Precision v accuracy Digital v analogue Signal to noise Processing stages Transmission Storage and dissemination Ground segment Overview of pre-processing stages Geometric, radiometric, atmospheric correction Multi/hyperspectral scanners Heritage Landsat, AVHRR (NOAA), EOS/NPOESS (NASA), ESA (Envisat, Explors etc.) Discrete detectors and scanning mirrors (JJ183) Pushbroom/whiskbroom linear arrays (JJ184) Across track scanning (LK 331, 337) Digital frame camera area arrays Detector types (CCD, LK 336) Hyperspectral area arrays Examples of the different systems LiDAR Vegetation First/last pass (discrete return), waveform Principles of lidar measurement Information content Radiative transfer Radiative approach RT theory at optical wavelengthgs Wave propagation, polarisation Tools for developing RT Canopy scattering models Scalar RT equation Extinction coefficient, Beer’s Law Simplifications for vegetation canopies Recollision probability theory RADAR principles RADAR: Definitions SLAR, SAR, IfSAR Principles Ranging and imaging Geometry Wavelengths SAR principles Resolution Azimuth, range ERS1 & 2 examples Radiometric effects Speckle RADAR equation Geometric effects Shadow Foreshortening Layover Surface interactions Moisture Types of interaction The RADAR equation Measurable quantities Calibration Interferometric SAR (InSAR) Principles Phase information Coherence Phase unwrapping Interferograms, fringes, DEMs Sources Problems Geomtetry Decoherence Accuracy Differential InSAR