1. Introduction to Field Informatics Chapter 1 Remote Sensing and Geographic Information System Kyoto University Graduate school of informatics Tetsuro SAKAI 1/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

2. An Overview of Remote Sensing Analyzed techniques of the characteristics and status of a target object without touching directly from the place left. Technical term was coined during the space age of the 1960s Using the reflection and radiation of electromagnetic waves Based on “All objects, if their types and environmental conditions differ, have different characteristics in terms of the reflection or emission of electromagnetic waves.” Using magnetic or gravitational force instead of electromagnetic waves 2/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

3. Application field of a remote sensing Remote sensing, which covers wide-scale terrestrial, atmospheric and oceanographic data collection as well as the monitoring of global-scale environmental shifts, has applications for a wide variety of fields. In terrestrial science, it is used as a means of acquiring and analyzing data about the environment and natural resources; such as data on land use, land cover, changes in vegetation and projections of crop growth and grain harvests. In oceanography, it is used to measure sea level, water pollution, the distribution of plant plankton, sea temperature and so on In atmospheric science, it is used to examine the composition of minor atmospheric constituents, such as carbon dioxide and ozone, and to analyze cloud formations and other weather phenomena. In the global environment age, the importance of the remote sensing becomes increasingly big. 3/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

4. Conceptual diagram of remote sensing Reflection of solar radiation Thermal radiation Reflection of microwave Earth observation satellite Visible spectrum/reflection infrared remote sensing: reflected sunlight Thermal infrared remote sensing ： heat radiation Microwave remote sensing ： reflection of emitted microwaves 4/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

5. Visible spectrum/reflection infrared remote sensing Measuring reflected solar radiation (visible or infrared) Observation is not possible at night or when clouds cover the sky The peak of radiation of sunlight is a visible ray area. Necessary to correct for atmospheric, topographical features and the position of the sun Example of usage Weather observation satellite ： the distribution of the cloud and the water vapor, observation of snow ice and floating ice Earth observation satellite ： land coverage, land-use change, vegetation and mineral resource 5/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

6. Thermal infrared remote sensing Measuring the thermal radiation which a target object emits Temperature observation by measuring the thermal radiation Human social economic activity observation by measurements of night-time artificial light Observation of discharge of thunder Example of usage Measurement of sea water temperature: weather observation and the fishing industry Observation in a hot spot :discovery of a brushfire and an accident Observation of night-time artificial light ： grasp the extent of damage in areas hit by earthquakes and other disasters 6/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

7. Microwave remote sensing The active method using Synthetic Aperture Radar (SAR). A microwave is emitted and the reflective wave is observed, so it‘s also possible to observe in night. A microwave which wavelength is long passes cloud, so corresponds to all-weather A microwave have directionality, so undergoes influence of the topography hard Example of usage Terrain analysis: the distortion of the topography by the crustal alteration Land cover: the paddy area, rice growth process and vegetation 7/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

8. Spectral Reflection Characteristics Shorter Wave of length Longer B G R Visible light Ultraviol et light Plant Soil Water Thermal radiation Reflection of solar radiation Strength of the reflection Strength of the radiation Near infrared Middle infrared Thermal infrared radiation radiation radiation Microwa ve Plant ： Reflection characteristic of chlorophyll, blue and red are absorbed, and green and near infrared are reflected. Soil ： There is a reflective peak in a visible area. Water ： reflect in the visible area, but absorb in the infrared area. 8/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

9. Wavelength range and Characteristic of Remote Sensing Wave-classNameWavelengthCharacteristics Visible LightBlue 0.4μm ～ 0.5μm Distinction of the soil and the vegetation Green 0.5μm ～ 0.6μm Vegetation activity Red 06μm ～ 0.7μm Distinction of soil and water, vegetation activity Infrared RaysNear-Infrared 0.7μm ～ 1.3μm Vegetation activity and distinction of land water and the topography SWIR 1.3μm ～ 3μm Judgment of the inland water area, geological feature reading, soil moisture content Mid-infrared 3μm ～ 8μm Thermal infrared 8μm ～ 14μm Temperature measurement Far infrared 14μm ～ 1 ｍｍ MicrowaveX-band 2.4cm ～ 3.75cm Reflect by leaves C-band 3.75cm ～ 7.5cm Reflect by leaves and a branches L-band 15cm ～ 30cm Penetrate through leaves, Reflect by trunks and the ground surface * The name is different depending on the fields, and SWIR is sometimes included in Mid-infrared. 9/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

10. The process of image data processing Ｚ Atmospheric correction is influential correction of scattering in the atmosphere Corrections using values that reflection ratio is already known Performing comparative calculations between spectral bands Geometric correction is the distortion of the sensor and correction of a map projection Comparing maps and images of the target area and designating several overlapping points Topography correction is correction of difference in sunlight reflection in sloping ground Correction using the angle and inclination of the terrain and the position of the sun Ordinary method is ratio calculation between the band Classificationprocessing Correctionprocessing Atmospheric correction Geometric correction Image classification Topography correction Image enhancement and feature extraction 10/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

11. Classification processing Image enhancement and feature extraction Color tone conversion and color composition using brightness histogram Spatial filtering Spectral feature extraction (principal component analysis, vegetation index,…) Textural feature extraction Image classification Supervised classification (wealth previous information): Using data from selected training areas, the statistical values are calculated and the entire target area is classified. The maximum-likelihood classification method is generally used. Unsupervised classification ( little previous information): Using the variables of random sampling pixels, they are classified several classes by cluster analysis. Using these statistical values, the entire target area is classified. Classificati on processing Correctionprocessing Atmospheric correction Geometric correction Image classification Topography correction Image enhancement and feature extraction 11/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

12. False-color and NDVI False-color image NDVI image Natural color ： Red, Green, Blue False color ： NIR, Red, Green Vegetation is shown to red Normalized Difference Vegetation Index （ NDVI):-1 ～ +1 NDVI = (NIR – RED)/(NIR + RED) NIR= the brightness value of the near infrared band. The activity of the vegetation is so high that the numerical value is big Ikonos satellite image showing the Kyoto Prefectural Botanical Garden and the surrounding area 12/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

13. GIS: Geographic Information System GIS is a system in which map information, along with various additional information, can be displayed and referenced using computers Application field Management of living infrastructure (house, road, water,…… ） Management of productive facility （ agricultural field, …. ) Management of a natural environment （ Forest, Park, watershed,... ） Disaster prevention and military use….. Four Ms plainly state the qualities of GIS Measurement of environmental variables Mapping of features Monitoring of environmental changes Modeling of plans or contingency plans 13/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

14. Concept of layers A layer is the unit of the data management in GIS Management by the respective layers every independent figure A conventional map condenses into 1sheet, GIS is made up of many separate sheets A layer is managed synthetically by position information ・・・・・・・・ RS classification Aerial photography Elevation Drainage systems Buildings Train lines Land use Roads Administrative boundary 14/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

15. Data Structures Concept Polygon Point Line Vector format data structure Raster format data structure B Ｂ B Ｂ Ｂ B Ｂ Ｂ B Ｂ Ａ Ａ Ａ B Ｂ Ｂ B Ｂ B Ａ Ｂ B Ｂ Ｂ B Ｂ B Ｂ Ｂ B Ｂ Ｂ A B The two representative data structures used in GIS are raster format and vector format. They have a merit and demerit respectively and are often combine used. Express spatial information by a point, a line and a polygon Express spatial information by grid 15/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

16. Acquisition of Positioning Information There are two types of satellite positioning systems. GPS (G lobal P ositioning S ystem ) is managed by the United States. GLONASS (Gl obal Na vigation S atellite S ystem ) is managed by Russia. GPS is widely generally used. In order to handle space information in GIS, positioning information is needed Until recently, positioning information was calculated on maps using a compass or measured from clearly-established locations (such as bridges, crossroads, benchmarks) on maps Nowadays, with satellite positioning systems, such as GPS, positioning information has become much easier to obtain 16/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

17. Positioning Methods used in GPS Single-point positioning Differential method Static method 17/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

18. Independent positioning method (Single-point positioning) Uses only one receiver Seeks the position of the observation point by measuring the false distance between that point and the positions of GPS. Four GPS satellites are necessary for correction of the receiver’s clock This method can position in real time, the accuracy of the measurements is comparatively low, with a margin of error of about ten meters. Example of usage navigation simple surveying 18/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

19. Differential positioning Method Observation at same time using multiple GPS receivers at the fixed benchmark position and at the measurement point. Error information is calculated in benchmark point and the position is corrected using the error information. At both measurement point, positional information is calculated with the same satellite GPS with a differential function and the corrective information from such as the beacon bureau are needed. The error are about 1 m. Example of usage Navigation support at neighboring seas and a harbor Simple measurement highly precise little 19/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

20. Static method positioning Using two highly precise GPS receivers The carrier phase of the GPS radio wave is measured and a base line vector between observation points is calculated. Need time for observation and analysis, but the measurement precision is high. the error is several mm Example of usage Highly precise control point surveying Scientific research activities such as measuring the movement of the earth’s crust 20/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

21. Processing of GIS + = Overlaying different themes layers are overlaid to create composite layers A buffer extracting target objects within a set radius from a specific point and line Data collection ： Collection of information in relation to the purpose of analysis Existing and relevant resources, such as maps, statistical information and field reports Pre-processing and data input ： Task of inputting collected data into GIS Requires the greatest expenditures of time and effort Database management ： Making and management of GIS database The basis of the GIS software, the general user non-participate Information analysis processing ： Analysis operation to draw information Information retrieval, the making of the new layer, modeling Information output ： Final results of analysis are output Example of information analysis 21/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

22. The standardization of and interrelation between data formats related to spatial data Standardization of the map information to support digital earth on the Internet KML (Keyhole Markup Language) Most GIS software GPS Google Earth Google Maps NMEA, GPX GML （ Geography Markup Language ） Basis of description of geographic information 22/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

23. Example of image transfer Google Maps Google Earth GIS image KML 23/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

24. Case Studies of RS and GIS Usage Land coverage in a basin is analyzed using a satellite image by a ASTER sensor with TERRA satellite (resolution 15m). Object place ： The Ishigaki-jima Island southern part geometric correction Land coverage classification Satellite image terrain map basin Land coverage figure of the basin unit GIS 24/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

25. Geometric Correction Yaeyama Islands Raw image Image after geometric correction Corrected using attached positional information for four corners and for the image's center The upper left of the Figure is Iriomote Island and the upper right is a part of Ishigaki Island. This figures are rendered using false color. the blue areas are shallow seas and the red area are vegetation. 25/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

26. Classification False-color imageImage after unsupervised classification Variables: the green band, red band, near-infrared band and the NDVI vegetation index. Method of classification: Unsupervised classification(15classes) Result ： Forest （ green ）, Farmland and a City area (pink color), Coral reef and Sea (light blue ) 26/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

27. Display in GIS with classification result Classification result, map of Geographical Survey Institute and each basin layer are overlaid in GIS. 27/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

28. Land Cover Classification Result Extraction of land cover classification result from drainage basin areas Drainage basin A Drainage basin B Drainage basin A Drainage basin B 28/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

29. Collection in a behavior track by GPS The routes traveled by mountain climbers (original image by Yoshimura Tetsuhiko) People visiting beauty spots including the national park increase, and natural destruction by the overuse is a problem Visitor's behavior track is collected and the activities and frequency are analyzed. A blue line and a red line in the figure indicate the difference of entrances and the thickness indicates a number of visitor. Visitors are concentrating in a part of upper-right and lower-left in this figure. 29/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.

30. 3-S Technologies Remote sensing (RS) Geographical information systems (GIS) Satellite positioning systems (GPS) The collecting and analysis of space information and their subsequent results are useful “tools” The information system with space information is various - from the large-scale tasks of the earth level such as the climate change analysis, to the small-scale tasks of the local level such as a disaster prevention system or the environmental map For the foreseeable future, the role of space information science, which brings real-world applications to geographic information, and the need for learning about the “3-S Technologies” are expected to continue to grow in importance. 30/30 Copyright (C) 2010 Field Informatics Research Group. Kyoto University. All Rights Reserved.