A method and system for displaying meteorological data distribution map of geographic information system GIS

Abstract

The present invention relates to a method and system for displaying meteorological data distribution maps of a geographic information system (GIS). The method draws a geographic meteorological distribution map based on the NCL language, sets the latitude and longitude boundary range of the projection of the geographic meteorological distribution map, adjusts the latitude and longitude range to be consistent with the meteorological distribution map, and overlays the meteorological distribution map on the GIS map; the geographic information system continuously and dynamically displays the meteorological distribution map according to the predefined grid point number and the drawing time of the meteorological distribution map. The above scheme can replace the direct data rendering method of GIS, and greatly improve the meteorological data display speed of GIS while ensuring the display quality.

Description

Technical Field

[0001] The present invention relates to a data display method and system, and in particular to a meteorological data distribution map display method and system of a geographic information system (GIS). Background Art

[0002] Meteorological distribution maps refer to the spatial distribution drawn on geographic drawings based on data from meteorological observations and forecasts, such as the actual observation maps and forecast maps of the meteorological station's temperature, wind speed, wind direction, precipitation, humidity, rainstorms, strong winds, high temperatures and other elements. Meteorological distribution maps have three important features. The first is that the map contains real geographical information, that is, the specific location of each region can be found by looking at the map; the second is the distribution color of meteorological elements, different colors represent different quantities, so that the meteorological conditions in different regions can be distinguished; the third is that the map has a legend of the quantity levels represented by different colors, and the legend can tell how much a certain color represents. The production of meteorological distribution maps requires professional meteorologists to use professional meteorological mapping software, such as NCL, GRADS, etc.

[0003] With the increasing demand for meteorological data in geography, electricity, agriculture, aviation, railways, highways and other professions or industries, many companies use geographic information systems (GIS) to display meteorological data. GIS systems, which have developed with the development of geographical science, computer technology, remote sensing technology and information science, enable people to combine geographic information data with computers to process, such as rendering meteorological data on geographic systems to display weather conditions in different regions. At present, the most commonly used GIS systems are Google Earth and ArcGIS. In practical applications, a GIS system has to manage a lot of very complex data, which may have tens of thousands of polygons, tens of thousands of lines, and tens of thousands of points. It is necessary to calculate and manage various complex spatial relationships between them. The amount of meteorological data itself is very large. For example, the meteorological data of a province at one time and with a resolution of 3km×3km contains about 20,000 grid points. If multiple time renderings are performed on the GIS system, the amount of calculation is huge. For general computers, there is a very slow and lagging operation perception, which affects the operation experience. Summary of the invention

[0004] In order to remedy the above defects, the present invention provides a method and system for displaying meteorological data distribution maps of a geographic information system (GIS), which can replace the direct data rendering method of GIS and greatly improve the meteorological data display speed of GIS while ensuring the display quality.

[0005] The present invention is achieved by adopting the following technical solutions:

[0006] A method for displaying a meteorological data distribution map of a geographic information system (GIS), the method comprising:

[0007] Draw a geographical meteorological distribution map based on the NCL language, and set the latitude and longitude boundary range of the projection of the geographical meteorological distribution map;

[0008] Adjust the latitude and longitude range to be consistent with the meteorological distribution map, and overlay the meteorological distribution map on the geographic information system GIS map;

[0009] The geographic information system continuously and dynamically displays the meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map.

[0010] Preferably, the drawing of a geographical meteorological distribution map based on NCL comprises:

[0011] Processing the acquired meteorological data file into discrete point data, and interpolating the discrete point data into grid point data according to the area covered by the meteorological data;

[0012] Reading the latitude and longitude information and meteorological element values ​​of the grid point data, and classifying the meteorological data into temperature levels according to the meteorological element values;

[0013] A meteorological distribution map is drawn according to the latitude and longitude information and the temperature level of the grid point data, and a geographical meteorological distribution map named after the current time is generated.

[0014] Furthermore, drawing the geographical meteorological distribution map according to the latitude and longitude information and temperature level of the grid data includes:

[0015] The grid points of geographical locations at the same temperature level are connected by a curve, and the area where the curve is located is defined as the drawing area corresponding to the temperature level. The drawing areas of the same temperature level in the geographical meteorological distribution map are represented by the same color, and the background part outside the area is drawn as a transparent color.

[0016] Preferably, the latitude and longitude range of the set geographical meteorological distribution map includes: latitude 18°~53.8°, and longitude 73.3°~135.3°.

[0017] Preferably, adjusting the latitude and longitude range to be consistent with the meteorological distribution map, and overlaying the geographical meteorological distribution map on the geographic information system GIS map comprises:

[0018] Accessing the geographic meteorological distribution image into a database of a geographic information system;

[0019] The latitude and longitude range of the geographic meteorological distribution map is located through the geographic information system, and the location information of the meteorological distribution map is displayed in the geographic information system GIS map through coordinate conversion and superimposed with the GIS map.

[0020] Furthermore, the coordinate conversion method comprises:

[0021] Coordinate calibration of the longitude and latitude range of the meteorological distribution map;

[0022] Convert the longitude and latitude range of the weather distribution map into hexadecimal coordinates;

[0023] By converting the coordinate system, the geographic meteorological distribution map is positioned and projected into a geographic information system (GIS) map.

[0024] Preferably, the defining grid point numbers comprises:

[0025] According to the grid longitude and latitude information, the target area is hierarchically divided into regional blocks using a quadtree structure;

[0026] Calculating the longitude and latitude intervals between the grid points of the area block;

[0027] The grid point numbers are determined according to the longitude and latitude intervals between the grid points; wherein the grid point numbers include the longitude numbers and latitude numbers of the grid points.

[0028] Furthermore, the longitude interval Loni and the latitude interval Lati between the grid points in the area block are determined by the following formulas:

[0029] Loni=(Lon1-Lon0) / LonNum

[0030] Lati=(Lat1-Lat0) / LatNum

[0031] Where Lon0 is the minimum longitude, Lon1 is the maximum longitude, Lat0 is the minimum latitude, Lat1 is the maximum latitude, Loni is the grid longitude interval, Lati is the grid latitude interval, LonNum is the number of grid points in the longitude direction, and LatNum is the number of grid points in the latitude direction.

[0032] Furthermore, the longitude LonNo number and latitude LatNo number of the grid point are determined as follows:

[0033] LonNo=[(lonX-Lon0) / Loni]

[0034] LatNo = [(latX-Lat0) / Lati]

[0035] Where lonX represents the longitude position of any grid point; latX represents the latitude position of any grid point, and the symbol [] indicates rounding.

[0036] Preferably, the geographic information system continuously and dynamically displays the geographic and meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map, including:

[0037] Get the area block corresponding to any grid point data according to the grid point number;

[0038] According to the drawing time of the meteorological distribution map, the meteorological distribution map is continuously superimposed to form a dynamic display effect.

[0039] A meteorological data distribution map display system of a geographic information system GIS, comprising:

[0040] A definition module, used for drawing a geographical meteorological distribution map based on the NCL language, and setting the latitude and longitude boundary range of the projection of the geographical meteorological distribution map;

[0041] An adjustment module, used for adjusting the latitude and longitude range to be consistent with the meteorological distribution map, and superimposing the meteorological distribution map on the geographic information system GIS map;

[0042] The display module is used for the geographic information system to continuously and dynamically display the meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map.

[0043] Compared with the closest prior art, the present invention has the following beneficial effects:

[0044] The technical solution provided by the present invention draws a geographical meteorological distribution map based on the NCL language, sets the latitude and longitude boundary range of the projection of the geographical meteorological distribution map; adjusts the latitude and longitude range to be consistent with the meteorological distribution map, and overlays the meteorological distribution map on a geographic information system GIS map. The direct data rendering method of GIS is replaced by image overlay; since the speed of image overlay far exceeds the speed of real-time rendering, the meteorological data display speed of GIS is greatly improved.

[0045] The technical solution provided by the present invention enables the geographic information system to realize continuous dynamic display of the meteorological distribution map according to the predefined grid point number and the drawing time of the meteorological distribution map; solves the operation lag problem of real-time rendering of meteorological data in the GIS system, and realizes the continuous dynamic display of the meteorological distribution map drawn based on the meteorological data with excellent display quality.

[0046] The technical solution provided by the present invention overcomes the problem that the amount of meteorological data in the prior art is very large. For example, the meteorological data of a province at one time and with a resolution of 3km×3km contains approximately more than 20,000 grid points. If the data at multiple times are rendered and displayed on the GIS system, the amount of calculation is huge, and there is a very slow and lagging operating experience, which affects the operating experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a flow chart of a method for displaying a meteorological data distribution map of a geographic information system GIS provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The following describes in detail the implementation scheme of the method of the present invention in conjunction with the accompanying drawings.

[0049] like Figure 1 A method for displaying a meteorological data distribution map of a geographic information system (GIS) is shown, comprising:

[0050] S1 draws a geographical meteorological distribution map based on NCL language and sets the latitude and longitude boundary range of the geographical meteorological distribution map projection;

[0051] S2 adjusts the latitude and longitude range to be consistent with the weather distribution map, and overlays the weather distribution map on a geographic information system (GIS) map;

[0052] The S3 geographic information system continuously and dynamically displays the meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map.

[0053] The NCL (NCAR Command Language) in step S1 is a high-level programming language designed specifically for scientific data processing and data visualization, and is particularly widely used in meteorological data processing and visualization. NCL is superior to other drawing software in that, in addition to the graphic display function, it also has a complete data processing module. Commonly used data processing methods such as empirical orthogonal function expansion (EOF), filtering (Filters), and wavelet analysis (Wavelets) can all be processed with it. At the same time, because it supports external calls in C language and Fortran language, its program is simple and easy to understand, and flexible and changeable; it has a special data interface with multiple meteorological data models. For example, to fully use all modules of the mesoscale numerical model WRF, it is necessary to correctly install NCL; in addition, NCL also has a complete map projection system and rich color effects, which makes the visual effect of its graphics more intuitive, becoming a new platform for international meteorological data display.

[0054] NCL sample drawing program, command to load drawing tool:

[0055] load"$NCARG_ROOT / lib / ncarg / nclscripts / csm / gsn_code.ncl"

[0056] load"$NCARG_ROOT / lib / ncarg / nclscripts / csm / gsn_csm.ncl"

[0057] load"$NCARG_ROOT / lib / ncarg / nclscripts / csm / contributed.ncl"

[0058] load"$NCARG_ROOT / lib / ncarg / nclscripts / wrf / WRFUserARW.ncl"

[0059] load"$NCARG_ROOT / lib / ncarg / nclscripts / csm / shea_util.ncl"

[0060] In step S1, drawing a meteorological distribution map based on NCL includes:

[0061] Processing the acquired meteorological data file into discrete point data, and interpolating the discrete point data into grid point data according to the area covered by the meteorological data;

[0062] Reading the longitude and latitude information and meteorological element values ​​of the grid point data, and classifying the meteorological data into temperature levels according to the meteorological element values;

[0063] According to the latitude and longitude information and temperature level of the grid data, a meteorological distribution map is drawn, and a meteorological distribution image file named after the current time is generated.

[0064] In order to facilitate the subsequent GIS platform to read the time when the picture was drawn, the meteorological distribution map is named according to the time. For example, the picture at 12:00 on February 2, 2018 is named 2018020212.png.

[0065] Among them, drawing a meteorological distribution map based on the latitude and longitude information and temperature level of the grid data includes: using a curve to connect the grid geographical locations at the same temperature level, defining them as a drawing area corresponding to the temperature level; wherein the drawing areas of the same temperature level in the meteorological distribution map are filled with the same color, and the drawing areas of different temperature levels are filled with different colors, and the background part outside the drawing area is set to a transparent color.

[0066] The color filling and setting can be achieved using the convert command of the Imagemagic software under Linux:

[0067] wks=gsn_open_wks("png",plot_name); set the image format to png format, gsn_define_colormap(wks,"matlab_jet"); set the image color system or implement it in Photoshop under Windows.

[0068] res@mpAreaMaskingOn=True;Turn on the drawing area limitation function;

[0069] res@mpMaskAreaSpecifiers = ( / "China:States" / ); Only the Chinese part is restricted to be drawn, and the other areas are white.

[0070] map = gsn_csm_contour_map (wks, varPlot, res); drawing command

[0071] draw(map); drawing command

[0072] frame(wks); drawing command

[0073] system("convert"+plot_name+".png-bordercolor white-border 1x1-matte-fill none-fuzz 8%-draw'matte 0,0floodfill'-shave 1x1"+plot_name+".png"); turns the background color into transparent.

[0074] In step S1, setting the latitude and longitude boundary range of the projection of the geographic meteorological distribution map includes: setting the latitude of the bottom boundary to 18°, setting the latitude of the top boundary to 53.8°, setting the longitude of the left boundary to 73.3°, and setting the longitude of the right boundary to 135.3°.

[0075] res@mpLimitMode = "LatLon"; Set the boundary mode to latlon.

[0076] res@mpMinLatF=18.0; Set the latitude of the bottom boundary to 18°

[0077] res@mpMaxLatF=53.8; Set the latitude of the top boundary to 53.8°

[0078] res@mpMinLonF=73.3; Set the longitude of the left border to 73.3°

[0079] res@mpMaxLonF=135.3; Set the longitude of the right border to 135.3°

[0080] In step S2, the projection mode and longitude and latitude range of the geographic information system GIS map and the meteorological distribution are adjusted. Figure 1 The meteorological distribution map is superimposed on the GIS map, including:

[0081] Connect the meteorological distribution image files to the database of the geographic information system;

[0082] The longitude and latitude range of the meteorological distribution map is located through the geographic information system, and the location information of the meteorological distribution map is displayed on the geographic information system GIS map through coordinate conversion and superimposed with the GIS map.

[0083] Overlay and adjustment can be performed through the AddImageOverlay function of Google Earth or the overlay analysis function under ArcGIS's spatial analysis.

[0084] The coordinate transformation method includes:

[0085] Coordinate calibration of the longitude and latitude range of the meteorological distribution map;

[0086] Convert the longitude and latitude range of the weather distribution map into hexadecimal coordinates;

[0087] By converting the coordinate system, the meteorological distribution map is positioned and projected onto the Geographic Information System (GIS) map.

[0088] In step S3, pre-defining grid point numbers includes:

[0089] The target area is hierarchically divided into several area blocks using a quadtree structure according to the grid point longitude and latitude information;

[0090] Calculate the grid longitude and latitude intervals within the area block;

[0091] The grid point numbers are determined according to the grid point longitude and latitude intervals; wherein the grid point numbers include the longitude numbers and latitude numbers of the grid points.

[0092] The grid longitude and latitude intervals within the region block are determined by the following formula:

[0093] Loni=(Lon1-Lon0) / LonNum

[0094] Lati=(Lat1-Lat0) / LatNum

[0095] Where Lon0 is the minimum longitude, Lon1 is the maximum longitude, Lat0 is the minimum latitude, Lat1 is the maximum latitude, Loni is the grid longitude interval, Lati is the grid latitude interval, LonNum is the number of grid points in the longitude direction, and LatNum is the number of grid points in the latitude direction.

[0096] The longitude and latitude numbers of the grid points are determined by the following formula:

[0097] LonNo=[(lonX-Lon0) / Loni]

[0098] LatNo = [(latX-Lat0) / Lati]

[0099] Where LonNo represents the longitude number of any grid point, LatNo represents the latitude number of any grid point, lonX represents the longitude position of any grid point, latX represents the latitude position of any grid point, and the symbol [] represents rounding.

[0100] Step S3, the geographic information system continuously and dynamically displays the meteorological distribution map according to the predefined grid point number and the drawing time of the meteorological distribution map, including:

[0101] Get the area block corresponding to any grid point data according to the grid point number;

[0102] According to the drawing time of the meteorological distribution map, the meteorological distribution map is continuously superimposed to form a dynamic display effect.

[0103] Since the response time of the geographic information system GIS to overlay a picture is in milliseconds, it will form a smoother display effect, which is much more efficient than directly rendering meteorological data.

[0104] Based on the same inventive concept, the present invention also provides a meteorological data distribution map display system of a geographic information system GIS, comprising:

[0105] A definition module, used for drawing a geographical meteorological distribution map based on the NCL language, and setting the latitude and longitude boundary range of the projection of the geographical meteorological distribution map;

[0106] An adjustment module, used for adjusting the latitude and longitude range to be consistent with the meteorological distribution map, and superimposing the meteorological distribution map on the geographic information system GIS map;

[0107] The display module is used for the geographic information system to continuously and dynamically display the meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map.

[0108] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0109] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0110] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0111] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application rather than to limit its protection scope. Although the present application has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading the present application, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, and these changes, modifications or equivalent substitutions are all within the scope of the claims to be approved by the application.

Claims

1. A method for displaying a meteorological data distribution map of a geographic information system (GIS), characterized in that: The method comprises: Draw a geographical meteorological distribution map based on the NCL language, and set the latitude and longitude boundary range of the projection of the geographical meteorological distribution map; Adjusting the latitude and longitude range of a geographic information system (GIS) map to be consistent with the meteorological distribution map, and overlaying the geographic meteorological distribution map on the geographic information system (GIS) map; The geographic information system continuously and dynamically displays the meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map; Adjusting the latitude and longitude range of the geographic information system (GIS) map to be consistent with the meteorological distribution map, and overlaying the geographic meteorological distribution map on the geographic information system (GIS) map includes: Connecting the geographic meteorological distribution map to a database of a geographic information system; The latitude and longitude range of the geographic meteorological distribution map is located by means of a geographic information system, and the location information of the meteorological distribution map is displayed in a geographic information system GIS map by means of coordinate conversion, and is superimposed on the GIS map; The coordinate conversion method comprises: Coordinate calibration of the longitude and latitude range of the meteorological distribution map; Convert the longitude and latitude range of the weather distribution map into hexadecimal coordinates; By converting the coordinate system, the geographic meteorological distribution map is positioned and projected into a geographic information system (GIS) map.

2. The method according to claim 1, characterized in that Drawing a geographical meteorological distribution map based on NCL language includes: Processing the acquired meteorological data file into discrete point data, and interpolating the discrete point data into grid point data according to the area covered by the meteorological data; Reading the latitude and longitude information and meteorological element values ​​of the grid point data, and classifying the meteorological data into temperature levels according to the meteorological element values; A meteorological distribution map is drawn according to the latitude and longitude information and the temperature level of the grid point data, and a geographical meteorological distribution map named after the current time is generated.

3. The method according to claim 2, characterized in that Drawing the geographical meteorological distribution map according to the latitude and longitude information and temperature level of the grid point data includes: The grid points of geographical locations at the same temperature level are connected by a curve, and the area where the curve is located is defined as the drawing area corresponding to the temperature level. The drawing areas of the same temperature level in the geographical meteorological distribution map are represented by the same color, and the background part outside the area is drawn as a transparent color.

4. The method according to claim 1, characterized in that The latitude and longitude ranges of the set geographical meteorological distribution map include: latitude 18°~53.8°, and longitude 73.3°~135.3°.

5. The method according to claim 1, characterized in that The defined grid point numbers include: According to the grid longitude and latitude information, the target area is hierarchically divided into blocks using a quadtree structure; Calculating the longitude and latitude intervals between the grid points of the area block; The grid point numbers are determined according to the longitude and latitude intervals between the grid points; wherein the grid point numbers include the longitude numbers and latitude numbers of the grid points.

6. The method according to claim 5, characterized in that The longitude interval Loni and latitude interval Lati between grid points in the area block are determined by the following formula: Loni=(Lon1-Lon0) / LonNum Lati=(Lat1-Lat0) / LatNum Where Lon0 is the minimum longitude, Lon1 is the maximum longitude, Lat0 is the minimum latitude, Lat1 is the maximum latitude, Loni is the grid longitude interval, Lati is the grid latitude interval, LonNum is the number of grid points in the longitude direction, and LatNum is the number of grid points in the latitude direction.

7. The method according to claim 5, characterized in that Determine the longitude LonNo and latitude LatNo of the grid point as follows: LonNo=[(lonX-Lon0) / Loni] LatNo=[(latX-Lat0) / Lati] Where, lonX represents the longitude position of any grid point; latX represents the latitude position of any grid point, and the symbol [] represents rounding; Lon0 is the minimum longitude, Loni is the grid longitude interval, Lat0 is the minimum latitude, and Lati is the grid latitude interval.

8. The method according to claim 1, characterized in that The geographic information system continuously and dynamically displays the geographic and meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map, including: Get the area block corresponding to any grid point data according to the grid point number; According to the drawing time of the meteorological distribution map, the meteorological distribution map is continuously superimposed to form a dynamic display effect.

9. A meteorological data distribution map display system of a geographic information system GIS, characterized in that: include: A definition module, used for drawing a geographical meteorological distribution map based on the NCL language, and setting the latitude and longitude boundary range of the projection of the geographical meteorological distribution map; An adjustment module, used to adjust the latitude and longitude range of a geographic information system (GIS) map to be consistent with the meteorological distribution map, and to overlay the geographic meteorological distribution map on the geographic information system (GIS) map; A display module, used for the geographic information system to continuously and dynamically display the meteorological distribution map according to the predefined grid point numbers and the drawing time of the meteorological distribution map; Adjusting the latitude and longitude range of the geographic information system (GIS) map to be consistent with the meteorological distribution map, and overlaying the geographic meteorological distribution map on the geographic information system (GIS) map includes: Connecting the geographic meteorological distribution map to a database of a geographic information system; The latitude and longitude range of the geographic meteorological distribution map is located by means of a geographic information system, and the location information of the meteorological distribution map is displayed in a geographic information system GIS map by means of coordinate conversion, and is superimposed on the GIS map; The coordinate conversion method comprises: Coordinate calibration of the longitude and latitude range of the meteorological distribution map; Convert the longitude and latitude range of the weather distribution map into hexadecimal coordinates; By converting the coordinate system, the geographic meteorological distribution map is positioned and projected into a geographic information system (GIS) map.

Images