IMPROVED DATA PROCESSING OF LANDSAT ...

Rjeas

Research Journal in Engineering and Applied Sciences 1(4) 229-234 © Emerging Academy Resources (2012) (ISSN: 2276-8467) www.emergingresource.org

Rjeas

IMPROVED DATA PROCESSING OF LANDSAT SATELLITE FOR URBAN CLIMATE STUDIES Laras Tursilowati1,2, Josaphat Tetuko Sri Sumantyo1, Hiroaki Kuze1, and Erna Sri Adiningsih2 1 Center for Environmental Remote Sensing (CEReS), Chiba University, Japan. 2 National Institute of Aeronautics and Space (LAPAN), Indonesia. Corresponding Author: Laras Tursilowati ___________________________________________________________________________ ABSTRACT Surface Energy Balance Interface Software (SEBALIS) has been created using Visual Basic 6.0 program, which can simplify the existing system and the formulation, so as to minimize the use of software products that are commercially available. Specifically, the novel framework of SEBALIS facilitates data processing by reducing repetitive and complex tasks implemented with the ErMapper 7.1 software. The climate variables calculated in SEBALIS are always saved in such a way that they can be reprocessed using the ArcView GIS 3.3 software. The significance of this study lies in the combination of these tools is useful for obtaining information on the distribution of urban climate variables such as surface temperature (Ts), air temperature (Ta), net radiation (Rn), soil heat flux (G), latent heat flux (L), sensible heat flux (H), and evapotranspiration (Etp) for each land cover in urban areas. The scheme of SEBALIS is composed of Input Design, Structure of Input Output Data System, Output, User Interface, Menu Structure of Surface Energy Balance Model, and Software User Manual. The system output is capable of displaying spatial distribution map, map scale, and attribute information. The user interface contains five forms for Intro (splash screen), Load Data, MDI, Display, and Layer Symbol. The results of SEBALIS can be directly obtained in digital values, which can immediately be visualized in the software itself. For further analysis, the results of SEBALIS can be processed with ArcView GIS in the shapefile format. The benefits of this research for the reading community is able to understand design the interface software to simplify the manufacture of satellite data processing. ©Emerging Academy Resources KEYWORDS: Surface Energy Balance Interface Software (SEBALIS), Visual Basic 6.0, Novel Framework, ErMapper, ArcView GIS, Urban Climate Variables ________________________________________________________________________________________ INTRODUCTION in the case of Visual Basic (VB), since the system There is an increasing recognition of the role of cities enables programming without the need for and urban regions as key engines of economic remembering detailed operation codes (Datta, 2008; growth, job creation and innovation – as well as their Prince, 2002). This situation has encouraged us to role as the major contributors to global warming. create the Surface Energy Balance Interface Software Climate impacts will result from global climate (SEBALIS) based on the VB platform. As a result, change, but how climate change impacts individual we can simplify the formulation so that the utilization metropolitan regions will vary (OECD, 2010). of other existing programs is reduced considerably in Therefore it is very important to monitor urban the development of simulation model. As an climate changes in relation to land use changes. One example, here we apply the novel VB system to of the ways to monitor these changes is using the analyzing the energy balance in big cities in satellite data. In the previous study (Tursilowati, Indonesia. 2006; Tursilowati et al., 2009), the analysis of urban climate variables is implemented by means of SEBALIS was created as a tool for supporting the successive application of several software systems research activities conducted by the National Institute integrated to collect, process, and analyze existing of Aeronautics and Space (LAPAN), Indonesia, and data. This whole process is often ineffective, Center for Environmental Remote Sensing (CEReS) resulting in quality degradation of the final product Chiba University, Japan. The distribution of energy because of the frequent change of data format during balance is closely investigated over various types of the repeated output/input protocols. In addition, more land coverage including water body, forest, industry, time and cost are of course needed when several plantations, residence, paddy fields, open land, independent programs are incorporated. The embankment, and cloud. Tables and charts presenting shortcomings of other program tools can be avoided surface reflectance (albedo), surface temperature (Ts), 229

Research Journal in Engineering and Applied Sciences (ISSN: 2276-8467) 1(4):229-234 Improved Data Processing of Landsat Satellite for Urban Climate Studies

air temperature (Ta), the components of energy balance (net radiation, Rn), soil heat flux (G), latent heat flux (L), sensible heat flux (H)), and evapotranspiration (Etp) are generated to design the necessary system models on the basis of relevant satellite images. The design of SEBALIS enables to reduce repetitive and complex tasks often encountered in ErMapper 7.1 calculations, since all calculations of climate variables are implemented in SEBALIS. The processed data can always be saved, and the result can easily be reprocessed using the ArcView GIS 3.3 software to obtain distribution maps of climate variables.

problem definition, system requirements analysis, system design, implementation and testing. Usage this waterfall method, is expected to minimize the repetition of some stages of development / execution systems built. The methodology describes the procedure of processing of raw data and initial processing of Landsat satellite images, data extraction to urban climate variables to the analysis and visualization. The urban climate variables consist of the albedo, Ts, Ta, surface energy balance components (Rn, G, H, and L), and evapotranspiration (Etp). The calculation methods and the formulation of climate variables are explained in Tursilowati, 2006 and Tursilowati et al., 2009. Initial processing of raw image data to be output ASCII data is done by using the Er Mapper 7.1 software. Landsat data extraction for the numerical calculations performed using SEBALIS that has been developed. While the reclassification process the data until the final layout is done using the software ArcView GIS 3.3. Chart design of Surface Energy Balance Model in this study shown as Figure 1. .

Visual basic is derived from the Beginner AllPurpose Symbolic Instruction Code (BASIC) programming languages, it is a Microsoft window programming language, visual basic program are created in an integrated development environment (IDE), which allows the programmer to create run and design visual basic programs conveniently it’s also allow a programmer to create working programs in a fraction of time that normally takes to code programs without using IDE (Ford, 2009; Foxall, 2010; Halvorson, 2010; Hassan et al., 2006). The wide spread use of BASIC Language with various types of computer (sometimes called hardware platform) led to many enhancement to the languages with the development of Microsoft windows graphical user interface (GUI) in the late 1980’s and the early 1990’s, the natural evolution of basic was visual basic which was created by Microsoft corporation in 1991 (Foxall, 2010; Hassan et al., 2006). With Visual Basic, can design programs, also known as applications, to accomplish just about any task can imagine (Siler and Spotts, 1998). Visual basic is the most widely worlds use Rapid Application Development (RAD) language, is the process of rapidly creating an application. Visual Basic provide a powerful features such as GUI, events handling assess to Win 32 API, objectoriented features, error handling, structured programming and much more. Not until Visual Basic appeared, developing Microsoft windows based application was a difficult and cumbersome process. Visual basic greatly simplifies window application development.

Figure 1. Chart design of Surface Energy Balance Model Interface Model Data Processing using ER Mapper 7.1. Software Landsat satellite data processing using ER Mapper 7.1 Software is divided into two stages, namely preprocessing and processing image classification. The pre-processing consists of import data, calling and display raster image, create a composite image, geometric correction image to image, and atmospheric correction. The processing image classification consist of image enhancement, masking land and sea, unsupervised image classification, and editing the land classification (USGS Landsat, 2003). The result of landcover classification was validated by using survey ground data.

METHODOLOGY An outline, the methodology carried out by Waterfall approach. Waterfall method is, generally in use in the development of a system or application software that has long been widely known, very powerful software development methodology and consists of four phases that, in general, map to the four phases of the Kumiega-Van Vliet model analysis, design, implementation, and ongoing system testing (Van Vliet and Hendry, 2004). This method is part of the Systems Development Life Cycle (SDLC) include several working processes, namely: planning and 230

Research Journal in Engineering and Applied Sciences (ISSN: 2276-8467) 1(4):229-234 Improved Data Processing of Landsat Satellite for Urban Climate Studies

Data Processing using SEBAL Software Interface Processing data using Surface energy Balance Model that receives input data in the form of a data Band 1,2,3,4,5,6,7, the result of land cover classification, and Digital Elevation Model (DEM) are stored in ASCII format. Then the simulation results of the program will produce the output value of the albedo, Ts, Ta, Rn, G, H, LE, and Etp. The results of the SEBALIS output is then processed by ArcView GIS 3.3 software for the reclassification process, map visualization, and analysis. In the model developed there are three core processes that build the model, the third process is to load the satellite data, displaying maps and spatial analysis, tables and graphs. The process can be seen on the drawing flowcharts in Figure 2.

RESULT AND DISCUSSION Design surface energy balance interface software consist of: 1. Input Design 2. Structure of Input Output Data System 3. Output 4. User Interface 5. Menu Structure of Surface Energy Balance Model 6. Software User Manual Input Design Input design that was built on the system aims to enable the users can access information easily. Description of the input system can be seen in the Table 1. The Input system in the SEBALIS consist of Data, Spatial object, Field attribute, Scale unit, Graphic and table simulation, and Data management.

In the process, the first time the system will read ASCII text data which is loaded by the user (the existing data structure can be seen in the discussion of the input data structure). Existing data processing systems, namely reading band data values 1, 2, 3, 4, 5, 6, 7, DEM and land cover. Then the system will select the type of data which is input, the data is included into the kind of data Landsat TM or ETM+. Then the system will proceed according to the existing formulation to obtain components of energy balance, surface temperature and air temperature as well as other components. Then the system will perform two processes: the first process, the system of filling the data in table and graphic simulation; second process, the system will make the process of reading the energy component of the balance sheet, the temperature of surface and air temperatures as well as other components obtained previously and the process of overlaying and cropping appropriate basemap existing of the area. The next step the system will convert the data into a format such cropping results shapefile (*.shp) and displays into map layers.

Table 1. Description of Spatial Energy Balance Model input No. 1.

Input Data

2.

Spatial object

3.

Field attribute

4.

Scale unit

5.

Graphic and table simulation

6.

Data management

Description The data needed in the environmental system in the form area basemap data and ASCII text data Digital Number (DN), Landuse and DEM. Users can select the areas that will be on display spatial distribution, by selecting the data contained in list combo box, and have input on the form map display and map display2 Users can define attributes that will be displayed. Attributes include components of energy balance, air temperature, surface temperature, NDVI and land cover. Users can determine the scale of the map unit layer to be displayed. This input is a user input to output graphs and tables as well as simulation Descriptive statistical values. User can select the input of land over classes components of energy balance will be displayed. Input data management functions as data management includes the process of importing data into the model environment, split the data and editing the value, such as land cover, if there are errors in the data input structure.

Structure of Input Output Data System To get the desired output, the system requires input data for processing. The required input data structures the system are text data ASCII and spatial data as follows: Text Data ASCII ASCII text data needed to process the value system of energy balance components, surface temperature, air temperature, NDVI and landuse into tables / graphics, as well as spatial maps. Value extraction of the data is the DN (Digital Number) Landsat TM satellite image / ETM band1, band 2, band 3, band 4, band 5 and band 6, band 7, Landuse, DEM (Digital Elevation Model).

Figure 2. Flow Chart of Surface Energy Balance Interface Software (SEBALIS) 231

Research Journal in Engineering and Applied Sciences (ISSN: 2276-8467) 1(4):229-234 Improved Data Processing of Landsat Satellite for Urban Climate Studies

1. The Initial Data The initial data is an ASCII text data that have not been converted into a form that can be used in the system environment. Data is the data of the extracted value of DN (Digital Number) which consists of three components (X, Y, Z). Data structure can be seen in the following Table 2:

3. 100 : Resolution 4. 373394 : Number of data 5. 169 : Julian day 6. 48.23 : Sun elevation angle (degree) 7. 107.408025,6.689039,49,38,30,72,39,135,19,3,370 : Xeasting (Longitude), Ynorthing (Latitude), DN of Band (1,2,3,4,5,6,7), DEM, and class of Landcover

Table 2. Data Structure X Y Z X = Value of Xeasting Y=Valueof Ynorthing Z = Value of Digital number (DN)

Spatial Data To show the spatial map was necessary *.shp format data. The data consists of the basemap data areas and data from running (the data previously processed within the system). The data structure consists of several attributes as seen in Table 2, namely: Shape, Fd, Easting (Longitude), Northing (Latitude), Ts, Ta, Albedo, Rn, Soilhf, Sensiblehf, Latenhf, Etp, and Landcover.

2. The Mosaics Data Mosaics data is data that is used in the system environment the data is the result of the mosaic process some data DN (Digital Number). These data will be processed / estimated and displayed on tables/graphs and spatial map. The ASCII text data structure is as follows: 1. "Bandung 2001" : Object study and year of data 2. "ETM" : Type of Landsat data

Attribute data is data needed to process the query component to its spatial distribution. The system will perform the query processing component of the cool user's choice, then display it on the screen. Data attributes represent data structures that form the spatial data of each region.

Table 2. Attribute data

Output The resulting output of the system: the spatial distribution map of energy balance components, air temperature, surface temperature, and landcover. In addition, the system can also display the form information is presented charts and tables and area of the attribute value and the value of descriptive statistics of the data estimates. Description of the system output can be seen in Table 3.

User Interface Display Interface available in the model shown in table 4. The display interface available in the model consist of Form intro (splash screen), Form load data, Form Multiple Document Interface (MDI), From display, and Form layer symbol.

Table 3. Description of Spatial model of energy balance output. No. 1

Output Display of Spatial distribution map

2

Map scale

3

Attribute Information

Description Displays the spatial distribution map based on input from the user, in this case the user can select the attributes of the components of energy balance, air temperature, surface temperature, or other component. The results will be displayed on a layer that includes a graphical map data. Displays map scale appropriate unit desired by the user. Displays the attribute values selected by the user.

232

Figure 3 shows the Form Load Data with Landsat ETM + satellite data path 122 row 065 dated December 22, 2001 which cover the area of Bandung, West Java-Indonesia. In this form load data, the data entered and compiled to be processed from the database, runs and displays the basemap region based on the data loaded, and the process of converting satellite data into the form of shapefile (*shp)

Research Journal in Engineering and Applied Sciences (ISSN: 2276-8467) 1(4):229-234 Improved Data Processing of Landsat Satellite for Urban Climate Studies

Table 4. Display Interface available in the model No. 1

2

Module Form intro (splash screen) Form load data (Figure 3)

2

Form MDI

4

Form display (Figure and 5)

5

4

Form layer symbol (Figure 6)

Description Form which will appear the first time when surface energy balance model executed. Form to enter and compile the data to be processed from the existing database. In this form there are tools to enter and compile the data to be processed from the database, and displays the basemap region based on the data loaded, and the process of converting satellite data into the form of shapefile (*.shp). Form Multiple Document Interface (MDI) is the form parent. In this form there is provided the menu bar to access the program. The menu bar located above the window program that contains pulldown menus associated with the model created. To select the menu can use the mouse. This bar menu will change according to the active window. The menu bar consists of main menu file, input data, simulation, map, window and help. Form to display the spatial map. On the form will display the spatial distribution map according to input from the user. In this form there are also map features like the legend, map scale, latitude and longitude. Form for display legend and manipulate the map display view.

Figure 5 is Form Display depicting the spatial distribution map of surface temperature of Bandung. As in Figure 4, here also shown several features such as legend of value of Ts, map scale, also info map will show that if we select a point on 107.58 oE, 6.9 o S with a white cursor denote residence with value of Ts is 34 °C.

Figure 5. Form Temperature (Ts).

Display

(Map)

of

Surface

Figure 6 is form layer symbol that represent symbol properties for the landcover of Bandung. This form appears when we click the legend on the form display in Figure 4. On this form layer symbol we can change the display color of the legend according to which we want.

Figure 3. Form Load Data Figure 4 is Form Display depicting the spatial distribution of landcover map of Bandung. In the form shown several features such as legend of landcover types, map scale, also info map will show that if we select a point on longitude 107.58 E and latitude 6.9 S with a white cursor denote a residence.

Figure 6. Form Layer Symbol Advantages, Limitations and Difficulties of the Study Some advantages of the study include:  The system can store data and information about landcover, DEM, and DN satellite neatly in the database.  Users can retrieve easily the data from database folder thereafter process it by running SEBALIS quickly.  Users do not need to write formulas and calculate variable repeatedly, because all been integrated in the SEBALIS program.  Once the process is completed the user can retrieve the results from shp folder to be processed in ArcView GIS.

Figure 4. Form Display (Map) of Landcover

233

Research Journal in Engineering and Applied Sciences (ISSN: 2276-8467) 1(4):229-234 Improved Data Processing of Landsat Satellite for Urban Climate Studies

SEBALIS design can still be developed as needed, for example to estimate the other urban climate variables (humidity (RH), temperature humidity index (THI), Bowen ratio (β), evaporative fraction (EF), etc.). Can also be added to the display interface in tables and graphs in the system Several limitations and difficulties in this study are:  For the other observation location is still needed the land classification process from satellite data using ErMapper software.  It takes knowledge, experience and skills in the processing of satellite data with ErMapper, visual basic programming, science of meteorology and climatology, and processing in ArcView GIS.  For best results accountable of SEBALIS output, need the appropriate validation with observation data. While the available observational data are not always complete.

REFERENCES Datta, A. (2008). Process Engineering and Design Using Visual Basic, CRC Press, Taylor & Francis Group, Boca Raton, FL, USA. Ford, J.L., JR. (2009). Microsoft Visual Basic 2008 Express Programming for the absolute beginner, Course Technology a part of Cengage Learning, Boston, USA. Foxall, J. (2010). Sams Teach Yourself: Visual Basic 2010 in 24 Hours, Pearson Education, Inc., Indiana, USA. Halvorson, M. (2010). Microsoft Visual Basic 2010 – Step by Step, Microsoft Press, Washington, USA. Hassan, A.B., Abolarin, M.S., Jimoh, O.H. (2006). The Application of Visual Basic Computer Programming language to Simulate Numerical Iterations, Leonardo Journal of Sciences, p. 125-136. OECD. (2010). Cities and Climate Change. OECD Publishing.

CONCLUSION To overcome obstacles that complicated and repetitive work in estimating urban climatic variables, it has been created surface energy balance interface software (SEBALIS) using visual basic program that integrates counting process so that it becomes more practical and easier. Urban climate variables that have been successfully estimated the albedo, air temperature (Ta), surface temperature (Ts), net radiation (Rn), soil heat flux (G), latent heat flux (L), sensible heat flux (H). Before the process in SEBALIS, the first step is land classification process is carried out using ErMapper software. Design of SEBALIS is consist of Input Design, Structure of Input Output Data System, Output, User Interface, Menu Structure of Surface Energy Balance Model, and Software User Manual. The system output consist of 1) Display of Spatial distribution map that user can select the attributes of the components of energy balance, air temperature, surface temperatu. re and other components, the results will be displayed on a layer that ncludes a graphical map data, 2) Map scale appropirate unit desired by the user, and 3) Attribute Information that display the attribute values selected by the user. The display interface available in the model consists of form intro (splash screen), form load data, form MDI, form display, and form layer symbol.

Halvorson, M. (2010). Microsoft Visual Basic 2010: Step by Step, Microsoft Press, Washington, USA. Prince, A. (2002). Murach’s Beginning Visual Basic .NET, Mike Murach & Associates, Inc., USA. Siler, B., and Spotts, J. (1998). Special Edition Using Visual Basic® 6, Copyright© 1998 by Que, USA. Tursilowati, L. (2006). Impact of Urban Development on the Climate and Environmental change in Surabaya, Indonesia, Proceeding of International Conference on Mathematics and Natural Sciences (ICMNS), Institute of Bandung Technology. Tursilowati, L., Sumantyo, J.T.S., Kuze, H., and Adiningsih, E.S. (2009). Comparison Evaluation of Evapotranspiration Estimation between Satellite Data and Observation Data, Proceedings of 120th RISH Japan symposium - International Collaborative Programs in Indonesia, p. 174-185. USGS LANDSAT 7, 2003, Science Data Users Handbook.

The results of SEBALIS can be directly retrieved from digital value, can also be visualized in the software itself. In addition to further analysis until final layout, the results of SEBALIS can be processed with ArcView GIS from shapefile (*.shp) format. This study has advantages and limitations as describes in discussion section, but overall design of the interface software is very useful for processing satellite data, and could be developed appropriate to user needs.

Van Vliet, B., and Hendry, R. (2004). Modeling Financial Markets: Using Visual Basic.NET and Databases to Create Pricing, Trading, and Risk Management Models, Mc Graw Hill, USA.

234