1. Introduction to Remote Sensing and GIS REM 611 REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM APPLICATION Dr HALILU AHMAD SHABA PANSHARPENED IMAGE OF NIGERIASAT-2 (ABUJA)

2. The Class  REM 611 REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM APPLICATIONS  Introduction of Remote Sensing and Geographic Information System  Remote sensing Applications to Disaster Management  Types and Sources of Remote Sensing and Geographic Information Systems Data  Data requirement for Disaster Management  Information Generation for Decision Making  Use of geo-information to visualize geographic data  Remote Sensing Data Application to Hazard analysis and mapping

3. What we are going to cover on this  Brief  Introduction of Remote Sensing and Geographic Information systems  Remote sensing  Definitions  How it works/ principles  EMR interactions  Types of Remote Sensing  History of Remote Sensing  Advantages of Remote Sensing  Geographic information system  What is GIS  Components of GIS  Advantages of GIS

4. DEFINITIONS OF RS

5. Remote Sensing: Defined  General: “..it is the art or science of telling something about an object without being in direct contact with it.” (Fisher et al. 1976; from Table 1.1 of your text)

6. Remote Sensing: Defined  More specific: “Remote sensing is the practice of deriving information about the earth’s land and water surface using images acquired from an overhead perspective, using electromagnetic radiation in one or more regions of the electromagnetic spectrum, reflected or emitted from the earth’s surface.” (Campbell)

7. Remote Sensing: Defined  Obtaining information about Earth’s surface from measurements, by aircraft or satellite sensors, of radiated energy

8. Remote Sensing: Defined  Remote sensing is the science (and to some extent, art) of acquiring information about the Earth's surface without actually being in contact with it. This is done by sensing and recording reflected or emitted energy and processing, analyzing, and applying that information (from Canadian Center for Remote Sensing).

9. How it works

10. Remote Sensing Process

11. Energy Propagation and usage Remote Sensing is more particular about Reflected Energy

12. Remote Sensing  Relies on detection, measurement, recording and analysis of electro-magnetic (EM) energy reflected or emitted from the objects of interest on the surface of the earth.  Different objects return different types and amounts of EMR and this is the basis for which various objects, features and conditions are assessed.

13. The electromagnetic spectrum  All objects above absolute zero (-273.15ºC or 0ºK) emit electromagnetic radiation  Nuclear reactions occur within the Sun which emits ER across a broad range of wavelengths called a spectrum  Some regions of this spectrum are visible (visible light) and some are invisible (infrared or ultraviolet)  Remote sensing relies on the measurement of this radiation

14. Radiation from the Sun has a short wavelength (shortwave). Radiation from the Earth has a long wavelength (longwave) The electromagnetic Energy The shorter the wavelength the higher the frequency

15. The Electromagnetic Spectrum μm = micrometer = 10 -6 meters The micrometer is the most common unit used to quantify the wavelength of EM energy Lillesand and Kiefer

16. Interactions of EM energy with earth surface features  λ the greek letter “lambda” is the symbol for wavelength  This figure is really a statement about the First Law of Thermodynamics. You will recall that this law deals with the conservation of energy.  All incident EM energy of a particular wavelength, λ, will be partitioned among reflection, transmission and absorption.  This basic principle hold for solids, liquids and gases. Lillesand and Kiefer

17. Types of remote sensing  Passive: source of energy is either the Sun or Earth/atmosphere  Sun - wavelengths: 0.4-5 µm  Earth or its atmosphere - wavelengths: 3 µm -30 cm  Active: source of energy is part of the remote sensor system  Radar - wavelengths: mm-m  Lidar - wavelengths: UV, Visible, and near infrared Camera takes photo as example, no flash and flash

18. 18 Remote sensing began in 1840 when balloonists used “new camera technology” to take pictures. At the turn of the century were “pigeon fleet” in Europe. REMOTE SENSING HISTORY

19. 19 Camera systems were placed on V-2 rockets tested at White Sands, NM after WW II. Sputnik in 1957 changed our outlook toward using outer space as a place from which to observe the earth.

20. 20 Milestones in the history of Remote Sensing 1800 : Discovery of infrared by Sir William Herschel 1839: Beginning of practice of photography 1847: Infrared spectrum shown by A. H. L. Fizeau & J.B.L. Foucault to share properties with visible light 1850-1860: Photography from balloons 1873: Theory of electromagnetic energy developed by James Clerk Maxwell 1909: Photography from airplanes 1914-1918: World War 1: aerial reconnaissance 1920-1930: Development & initial application of aerial photography & photogrammetry/ routine use of aerial photos by various government agencies 1929-1939: Economic depression generates environmental crises that lead to governmental application of aerial photography.

21. 21 Milestones in the history of Remote Sensing 1930-1940: Development of radars in Germany, US & UK 1839-1945: World War II: application of nonvisible portions of electromagnetic spectrum, Development of infrared films training of persons in acquisition and interpretation of airphotos. 1950-1960: Military research and development for intelligence gathering 1850-1860: Photography from balloons 1956: Colwell research on plant disease detection with infrared photography. 1960-1970: First use of term “remote sensing”, start TIROS weather satellite, Skylab, development of digital image processing with multispectral scanners

22. Milestones in Remote Sensing  1972: The launch of the Earth Resources Technology Satellite (ERTS-A); later renamed LANDSAT I. This was the first satellite dedicated to civilian remote sensing  1970-1980: Rapid advances in digital image processing  1980-1990: Landsat 4: new generation of Landsat sensors  1986: SPOT French Earth Observation satellite  1980: Development of hyperspectral sensor

23. 3 broad categories of spatial resolution available  High resolution (0.6-5m)  IKONOS, Quickbird, Orbview, NigeriaSat-1  Moderate (10-80m)  MSS, TM, SPOT, Aster, NigeriaSat-1  Low (250m – 4km)  AVHRR, MODIS

24. Field of Application Wageningen 1999

25. ADVANTAGES OF REMOTE SENSING  Improved vantage point, synoptic view  Broadened spectral sensitivity and amenability  Increased spatial resolution  3-D perspective  Historical record  Rapid data collection and repeat coverage  Quantitative analysis  Cost savings  Multiple use