Med-Hycos - the Software Tools
Med-Clim Viewer: Linear and Spatial Representation of Monthly Data
by Pelczer Ildiko, National Institute of Hydrology and Meteorology, Romania
1. An overview
The main purpose of the product is to give to the users a tool for linear and spatial visualisation of monthly rainfall and temperature data. In order to satisfy this purpose the product offers to the users a friendly interface and has the basic features requested from any graphical representation of data: different type of representation, simultaneous representation of two kind of data from selected stations, regression representation, printing and zooming possibilities.
1.1. Computer components needed
As the product is PC oriented, the application can run on a PC with more than 8MB of RAM, at least 100MB of free space on the hard disc, a printer, screen with more than 600*400 pixels resolution and an Internet connection.
The needs of program environment
This product uses the Windows’95 environment and can be installed under all latest versions, Windows NT included.
As the database is given with the program, it is not required to have ACCESS (which is a part of Microsoft Office). However if the user wants to see the database directly he will need an ACCESS’97 installation.
It is not necessary to install ODBC drivers for Oracle or ACCESS before using Med-Clim Viewer.
As an exclusive feature for remote Oracle users, this product includes the following Oracle product: SQL*Net version 2.3.4. This product maintains the interface between the TCP/IP network (Intra Net and Internet) and Oracle access modules. This product has to be installed by the user from the ORACLE directory from the MED-HYCOS CD-ROM.
First the user has to extract on the hard disc the contents of the compressed file oo4o805.exe which is given to provide the connection with the remote Oracle database only to registered users without redistribution rights.
From the directory where this file is unzipped choose the directory win32/install and run the Setup.exe program. It is advised to use English language for the installation of Oracle products. At the same time the user should take care of the Windows “Regional Parameters” (Start >> Parameters >> Configuration Panel >> Regional Parameters >> Number >> Decimal Point). Be sure that the corresponding character is the point (.); if it's not, change it to the point character. From the option list install SQL*Net 2.3.4.
This installation creates an entry in the main Windows menu: Start – Programs - " Oracle for Windows 95 ". From this entry choose " SQL*Net easy configuration ".
4.1. In the first window choose: " Add database alias ". In the blank field enter " world ".
4.2. For the protocol choose " TCP/IP ".
4.3. For the host name enter the name of the web server of Med-Hycos project "medhycos.mpl.ird.fr" or the substituted name from the file “hosts” given with the installation of Data Manager & Retriever.
4.4. In the field "data base instance" enter "HMD". Save the configuration and exit the menu.
After the new start-up of Windows the user can test the connection with the remote database.
5. What tests to make?
5.1. The first test checks the TCP/IP connection: from a DOS screen run the command line "ping medhycos.mpl.ird.fr". If the remote computer answers, you have the TCP/IP connection. If not, check if the “hosts” file (Windows directory) contains the corresponding line for the Med-Hycos server. If not, add it from the “hosts” file from Data Manager Installation (directory " Program Files\RoRetr ".
5.2. The second test checks the connection with the database: from the DOS prompt enter " tnsping world ". If the remote computer answers, you have a working SQL*Net layer. If not, check the similarity between host name in “hosts” file and the host name in " SQL*Net easy configuration ". If necessary, install again SQL*Net.
In the installation directory of the application the user can find a file ("HOST") with the name of the MED-HYCOS host, this name should be added to the users host file.
1.2. The installation
The installation package contains 19 files: the program setup.exe ; the list of installed files: setup.lst; 17 compressed CAB files.
The program installation has to be made with a common set-up program, started by the setup.exe.
In the case where the set-up program asks for a new Windows start-up or the change of existing files, the user should continue the installation and if possible to keep the newest files.
After the installation with setup.exe, in the working directory you will have the following files: MedClim.Exe, Algorithm.doc, Clima.mdb, optFile.ini, Surfer.dll, st6unst.log.
1.3. Observations about the data
The source of data used in this application is the Global Historical Climatology Network and it consist from monthly temperature and rainfall data for more than 700 (cumulated) stations from the mediterranean region and for a period between 1850-1990. For security reasons the monthly data is not available for the users from inside the application, but it can be requested from the Global Historical Climatology Network center. The derivated data (average monthly and average yearly data) is accessable for the users from the Access database.
2. Instructions to Use
After the installation of the program " Med-Clim Viewer " a shortcut will appear in the main Start menu of Windows. So you can start the program from this entry.
General rules for reading: Entries from the menu are in bold characters in parenthesis; Frames and panels are in underlined italics in parenthesis; Buttons are in italics in parenthesis.
The program shows a main window with one line of menus:
2.1. " Options "
The optional parameters can be changed after the installation. The purpose is to let the user choose the right connection type, the default value of the connection type is ACCESS, which means a connection with the local Access database.
In case of Access connection some features of the tool are not available (those using the measured data).
This entry allows you to exit the program.
2.2. " Linear_Graphical_Representation "
The option allows to represent monthly temperature or/and rainfall data, as time series ( the existing period). After launching the option the program will ask for the requested period, specified in the following window:
Selecting the begin and the end of the period, the available stations for representation will be those ones which have data in the requested period. Choosing "ALL" for the period the user will have the existing period in database for the selected combination of station, agregation level and variable available for representation. The period can be modified after drawing, so is not neccessary to relaunch the options for selecting another period. Pressing OK, the next window will be shown:
First selection to be made is the one of the variable: monthly rainfall or monthly temperature data. After selecting the variable the user has to specify the agregation level. The program offers three possibilities: monthly values (available just in the case of ORACLE connection), averaged monthly values and averaged yearly values. Depending on your selection in the station name and station number combo boxes you will have the list of those stations which have the specified data, for the specified period. Period can be changed from the combo boxes labeled "Period", by specifying the beginning and end of the desired period. After the very first selection the only enabled button is "Launch program", pressing it the graph will be showned and the datagrid filled with the corresponding values.
Other available buttons are related with the chart type or different utilities for showing more informations about stations.
In the Option frame:
Add_Graph: if the user wish to add a new graphic to the chart, after selecting the desired values for the variables, he has to click on this button and the chart will be refreshed. In the case of changing the aggregation level, only the last selection will be showned. In case of changing the variable type, the user will be asked if the other axes (the right or the left, depending on which one was used lately) to be used for gridding or not. Measurement units are C0 for temperature and mm for the rainfall.
Clear: button for clearing the chart. Selections done before are kept.
Add_To_Val: by pressing this button the user can add to the values of the last added chart the initial values. This operation can be a good solution when the represented values (from more than one station) are in the same range of variation and is difficult to tell the difference between them.
Stat.Info: Shows a window with statistical information about the data for the selected combination. The information is avalaible in case of Oracle connection.
Information is showned about the last selected station.
The Oracle ID is the WMO number of the station (the first five digits), followed by two extra digits for a sequential numbering. In case that the station has a WMO number, the last two digits will be 00, otherwise the first five digits are the WMO number of the nearest station (with assigned WMO number) followed by an index in order to give to the stations an unique identification number. In the description field, the variable marked with a '*' is the current variable, about which information is shown. If the second "Variable" field is filled, it means that for the respective station there is also data of the other kind.
Gen.Info: By pressing this button the user will have on the screen, in a window, shown the general infomation about the station.
Print: allows user to print the image and also to make the neccessary settings for the print job.
Close: by pressing, permits to close the general window opened by selecting the Linear_Graphical_Representation option and return to the general menu.
In the Graph Options frame:
Mean: draws the mean value for the data serie (the mean is calculated for the last selected combination of data, agregation level and variable).
Regresion: draws the line representing the calculated values on the basis of a linear time regression.
ST.Dv: draws the lines at the level of the values (mean ± standard deviation) on the chart.
Stck: significant only for more than two represented series. If checked will stack the series, meaning that the maximum value on the chart grid will be the sum of the maximum values from the series. In this way the graphs are more lisible.
Scat.: available only in the case of two represented series and will change the chart into one with scattered values, having the two axes values from the series.
The Line, Bar, Area, Pie, 3D buttons are for choosing the type of the chart, respectivelly to have line between the represented values or to be other type of drawing. In the situation in which for the selected combination of variable, agregation level and station there are singular values (the case of missing data), the way to see the data represented is to choose the Bar representation of the data.
The option is similar to the previous one with the exception that represents the existing period as yearly series, overputting the available years of data and, with dotted line, representing the monthly average on the existing period. The user begins again with the selection of the desired period and then, by specifying the station and variable obtains as result the overlaped graphs of data. This option is accesible only in Oracle connection with the database, because is using monthly measurements. The obtained window is the following:
The buttons on the right of the image have the same functionality as in the case of the previous option. The command-buttons in the Option frame were already described at the previous option. In the List of years frame, command buttons and combo boxes are related with the selection of drawn years. Initially all the avalaible and selected years are drawn, after representing the data, the user can remove a year or all the years, then add the selected ones ( multiple selection is possible, the selected items are marked with the sign "*"). At the end of the selection, redraw is effectuated by chosing the button End_select and redraw.
The last two buttons from this frame are associated with visualisation of the selections: the selected years and the one of the yearly average values for the existing period. This later information is shown in a new window, user can exit the window by clicking on the top right.
2.3. " Spatial_Graphical_Representation "
This option allows the user the representation of interpolated data for the selected aggregation level and variable. The option's window is:
Before the pressing of the "Launch program" button the user has to select the variable type (avalaible are: rainfall monthly and temperature monthly), the interpolation level (which has the same significance as in the linear-graphical-representation the aggregation level) which can be: monthly values, averaged monthly values and averaged yearly values.
In the case of monthly values, the user has to specify the year and month, for averaged monthly values the month and in case of the interpolation level set to averaged yearly values, he has to provide the year that he is interested in. Data is read from database, so in this situation all interpolation levels are available for both connection type. If the requested combination of the data is found in the database, the interpolated values are drawn, displaying in the same time the country borders.
Moving the mouse over the display the user will have the interpolated value of the region - in which the mouse pointer is - in the "Interpolated Value" box. Clicking once on the drawing will display the name of the nearest station and in the case of Oracle connection the value measured at the station for the specified period. At the bottom of the window the user will have general information about the interpolation, in the case of Oracle connection is displayed the number of stations considered for the interpolation, the minimum / maximum value for the specified period and the stations names where there were measured. In the case of Access connection these informations are not available.
The scale on the right side of the drawing is standard one, one for temperature and one for rainfall and is chosen in the way to fit inside of its range more than 95% of the values. For a better result data from not mediterranean countries (but neighbours to them) are considered. Even so, some results can be eronous, depending on the spatial distribution of the stations, on one part and one the other hand, on the relief (which is not taken into account in the interpolation proccess).
There are three buttons available in the SHOW frame:
Basins: If checked, on the drawing there will be also shown the basins from the mediterranean countries.
Rivers: If checked, on the drawing there will be also shown the rivers from the mediterranean countries.
Stations: If checked, on the drawing there will be also shown the stations from the mediterranean countries. In case of Oracle connection, the displayed stations will be those ones which are considered in the interpolation proccess (they have values for the specified combination of data); for Access connection all available stations will be shown.
Changing the values for the above mentioned check-button will cause an automatic redrawing of the map. Clicking on the map can take some seconds before showing the informations depending on the connection type and the computers features.
The DRAWWIDTH frame refers to the width of the line used in the drawing of the countries borders. The default value is set to 2 pixel, the user can try the 1 pixel width representation, but has to be aware that the result will depend on the monitor's features. In the case of a wrong result the user should use the 2 pixel width line. Setting this buttons will not cause an automatic redrawing, so the user has to relaunch the application, by pressing the "Launch program" button.
The zoom possibilities were also implemented in the program. By pressing the button SHIFT and simultaneously the left button of the mouse, dragging and then releasing both, as result we will have the image between the selected coordinates. As observation has to be said that the sea surface will not be coloured in blue in zooming. Consecutive zooming is possible and by pressing CTRL+SHIFT+click on the left button of the mouse on the image the previous image will be loaded and by pressing in the same time ALT+SHIFT and clicking with the mouse on the image, the initial ( the whole Mediterranean region) will be drawn again.
This option allows to execute the interpolation on user-specified region. First step is to make the selection of the region, by the following window:
By specifying the variable, aggregation level and date as result of pressing the Launch Program button, the user obtains the image of the mediterranean region and the stations which have data for the specified selection. The number of available stations is displayed on the bottom part of the window and is updated in Oracle connection. The possibilities of choosing a region are the following: specifying a country from the Country combobox, specifying a basin from the Basin combobox, or selecting a region by Select region button. In the last case, the region will be adjust by a ration for aspect. By selecting Show_Selected_Area, the user can visualise the selection, having on the bottom part the information about the coordinates of the region.
Accept_Values_Continue is the button by which the user validates his selection ( after visualising it with Show_Selected_region) and the program offers the next window for executing the interpolation.
The Cancel button assures the return to the main menu.
In case of a wrong selection, the user can return to the initial map ( Initial_Map button) and make a new selection.
As result of an accepted region on which interpolation will be executed, a new window is loaded:
The Countries, Rivers, Basins, Stations check-boxs at the top left of the window allow the drawing/not draing of the respective layers. The option button Drawwidth refers to the width of the line, used in drawing.
In the Selected values frame informations from the selection are shown, relating to the variable, date, aggregation level and about the scale used in drawing. If for interpolation measured values are used, the scale is in Usual units, otherwise is used a relative scale.
The interpolation is executed by pressing the Redraw button, as result at the bottom of the window maximum and minimum informations are shown, the number of considered stations.
General functionalities connected to mouse are available: by moving the mouse over the image, in the Interpolated Value box the interpolated value is shown. By clicking on the image, the nearest station and the measured value ( information avaliable only in Oracle connection) are shown.
This option also allows to user to compute an average value on a user-defined surface. The frame Region selection for average initially has to options available:
By checking this option, the combo box become enabled, allowing to choose an already defined region, saved into the database ( Acces or Oracle depending on the connection established in the Options menu item) on which an average to be computed. If the region lies inside of the drawn region, by chosing a region, is automatically drawn and computed the value, shown on the bottom part of the window, in the text box: Computed average value. The average is calculated as a surface weighted average, based on the interpolated values. Once the computing executed the value can be save into the database, by checking the Save value option from the same frame. The value can be transferred into Oracle/Acces, by checking the appropiate boxes.
This option allows to the user to define a new polygonial region on which an average value to be computed, based on the interpolated values. The process began by clicking on the Begin_Draw button, after that by clicking o the picture the poligonal region is drawn. The user can finish the drawing by clicking on the Close Draw button, which will close automatically the polygon. By clicking on the Int. point the program waites for the user to specify the interior of the region he drew. By this operation the region is coloured in blue and then by choosing the Analyse button, an average value is computed and shown in the bottom part of the window. The new region, as well the value can be saved, by checking the Save polygon ( and specifying an unique identification number and name) followed by the Go button, and by Save value button, respectivelly. The transfer between Access/Oracle is done by chosing the appripiate buttons from the same frame. Once a new region defined and saved, in the future can be used for computing, by selecting it from the combo box of existent regions.
This option mainly has the same facilities as the previous one, with the difference that first a region is selected on which the user can work, by selecting and changing the selection of variable, aggregation level. The same facilities of selecting an existing region or defining a new one are included.
2.4.1. "Linear representation"
This option is identic with the one from Linear graphical representation - Time series with the only difference that instead of choosing a station, a basin has to be chosen.
2.4.2. "Yearly representation"
This option is identic with the one from Linear graphical representation- -Yearly series with the only difference that instead of choosing a station, a basin has to be chosen.
2.4.3. "Spatial representation"
By this option is possible to represent the derivated average values for a basin ( based on the interpolated values for the same period and variable), for a selected period and variable/aggregation combination in the whole mediterranean region, by coloring the basins surface with the colour corresponding to the value.
The scale used for representing the computed values ( based on measured or relative interpolated values) is the same as the one used for interpolation.
The check butons Rivers and Station reffers to the possibility of drawing or not the respective layers, the Drawwidth has the same functionality as mentioned at other options.
In the Basin frame the user has the information about the basin on which the user clicked with the mouse and the value associated.
By chosing this option the user can see the animated images with the interpolated data on the whole mediterrenean region, for the selected period, variable and aggregation level.
In the first two boxes we have the possibility to specify the variable and the aggregation level, by clicking on the Retrieve_images the images for the user specified period are loaded and their display can be controled by the command buttons showned in the Action frame. In the lower part of the window the actual year and month is displayed.
For all the images the same scale is used.
For exiting this option, user has to click on the closing button on the top-right of the window.
This option has the same conception as the previous described one, but is displaying the interpolated data for basins. Actions and informations are similarly structured.
2.6. " About "
The window displayed after choosing this options offers general information about the project.
The selection of this option automatically launch an editor to show the Algorithm.doc document, which contains information about the interpolation method. In case that no editor is found an error message is displayed.
The selection of this option automatically launch an editor to show the Manual.doc document, which contains the user manual of the tool. In case that no editor is found an error message is displayed.
3 The Access database
The Access database contains all the data, except the monthly measured values, so there are the following tables: TBSTPMMA - averaged monthly temperature data, TBSRFMMA - averaged monthly rainfall data, TBSTPMYA - averaged yearly temperature data, TBSRFMYA - averaged yearly rainfall data, PRCSTAT - general information about stations, DATATTYP - stored datatypes, BASINS - informations about basins, COUNTRIES - informations about countries, RIVERS - informations about rivers, INTPLDT - interpolated data, BAZAVER - averaged values for basins, BAZAVERR - averaged values for basins based on relative interpolated values, BAZDIV - informations about the division of the basins, based on the square-structure of the interpolated values, BAZPOINT - informations about the division of the basins, based on the square-structure of the interpolated values, REGDATA - informations about average values computed over a region, REGION - informations about the user defined region.
The structure of data tables are similar: Station ID, Date, Value (TBSTPMMA, TBSTPMYA, TBSRFMMA, TBSRFMYA)
The structure of PRCSTAT: Cntry_Cod, Station_ID, Station_Name, Station_Latitude, Station_Longitude, Station_Elevation, Data_type1, Data_type2.
The structure of DATATTYP: Data_type, Measure_unit, Table_Name, Description, Short_Name_for_Datatype.
The structure of COUNTRIES, BASINS, RIVERS: ID, Name, Coordinate.
The structure of INTPLDT: Date, Agregation_level, Values.
The structure of BAZAVER (BAZAVERR) : BID, Whe, Aag, Value.
The structure of BAZDIV: BID, Bpointx, Bpointy, Snrx, Snry, Sarea.
The structure of BAZPOINT: BID, Bpointx, Bpointy, Snrx, Snry, Sarea,Bna.
The structure of REGDATA: PID, Whe, Val, Aag.
The structure of REGION: PID, Pna, Dat, Intx, Inty.
The structure of the Oracle database is similar to the Access database, containing beside the above mentioned ones two tables for the monthly rainfall and temperature data.