Web GIS Lab 2

Goal and Background

The goal of this lab exercise was to introduce us to the process of authoring geospatial data in order to create and host geospatial web services. The services are hosted via ArcGIS online and the ArcGIS server we have for the Geography department at UWEC. Several techniqes were learned to for different kinds of web services like shape files, Excel CSV file, ArcMap and the ArcGIS server. Another component of this lab was an introduction to authoring and creation of a feature access service where end users can make edits.

Methods

Part 1 Publishing feature hosted services through ArcGIS Online

The first step for this lab was to download the data provided for us by Dr.Wilson. It comes in a zipped folder which we saved in our own files and unzipped. Inside one of the folders are shapefiles for the major transportation routes in Wisconsin. The folder included interstates, highways, major cities, and the Wisconsin counties. We selected those four shapefiles and compressed them and remained them for later use. Once saved we then signed into our ArcGIS online accounts and went to our content and then the add tab. This is where you add data like data layers to the maps. We added that compressed file containing the transportation data and added tags so that it can be easily found when searching for data. The next step is to publish the data after which there will be a new feature service in your content. That feature service includes all 4 of those shapefiles and can easily be added to a web map by clicking open and add to new map. Figure 1 is the web map I created using this feature layer service.

Figure 1 This is a map showing the transpiration routes in Wiscsonsin. There are also the counties, major cities and I added a layer with the Marathon gas stations. This created from the shape file data.

Shapefile is one kind of data that can used another is an Excel CSV file. For this lab we are using a CSV containing lat long positions of fires in Wisconsin during 2004. The first step is to save the Excel sheet as a CSV instead of the default file type. CSV are usually used for point data. We went about adding this data to ArcGIS Online the same way as the shape files only we had to select so that the point_X field is set to longitude and the point_Y field is set to latitude. This is how ArcGIS Online know where to place the points. Once the data is added it will show up again as a feature service. Open it on a new map and then we made some changes the pop ups which contain information about each fire location. You can do this be going to the configure pop-up tab and select which field you want to display. In this case we chose to display just he date the fires occurred. Figure 2 is the fire data from the CSV file.

Figure 2 This is a map showing that fire occurrence data from 2004 in Wisconsin. This is created with the CSV file.

The last kind of file we can create a feature service from is an ArcMap file. This is a little bit more complicated but still easy to do. We added river, stream and lake data to an ArcMap document and saved the whole document. Once saved we signed into ArcGIS Online through ArcMap and then you share the file as a service. We use the Geography hosted service to publish the data but before it can be published we had to add a description, summary and tags we also made it so an end user can update, create and run query on the data but not delete it. We then choose to share it with the 455 class and hit analyze which makes sure there are no issues. If no errors occur the service can be published. Again this will show up in your content in ArcGIS Online. Figure 3 is the web map created with this data.

Figure 3 This is a map showing that feature service containing the lakes, rivers and streams data. This was created from ArcMap.

Part 2 Publishing a tiled map service using ArcGIS Server

The step is to connect to our enterprise geodatabase in ArcMap. Once we are connected to our own folder we then added some data to the server. We imported land use land cover data, again provided by Dr. Wilson, of the Eau Claire, Altoona and Chippewa Falls areas. Once added to the map the data was published through ArcMap just like the river, stream and lake data. With this data however we want to make sure that it is being cached or partially preloaded so that when I want to access the map the server does not have to find it which reduces server time and processing power. Then run the analyze again and publish the data. Once published the next step is to access it. This is done through a URl which leads to the ArcGIS Server Services Directory. Inside this directory you find your folder, find the file just published and open it using ArcGIS.com. 

Part 3 Author a map document, create a feature service and add to a web map

This section is working with hurricane and earthquake data. Again import these to the enterprise geodatabase and then add them to the map. We made some adjustments to the symbology of the two dataset to make them more aesthetically pleasing. Once the symbology is adjusted we then turn this into a time enabled map. This means that there is a slider and as time progresses more hurricanes and earthquakes are added to the map. Again using the ArcMap way of publishing we publish this data this data to the ArcGIS services Directory. The next step is to add this data to a web map. In ArcGIS Online we go to the add tab and choose to add a layer from the web. We then copy the URL of the feature saved in the directory and paste it into the add layer box. It will go to that URL and retrieve the feature service. It is added to a web map where we again made changes to the pop-ups to only display certain information. ArcGIS Online recognizes that this layer is time enabled and displays a slider at the bottom of the map where you can adjust the time interval and how fast the slider moves. We chose 6 months for the time interval and have the speed about 3/4 of the way to fast. Figures 4 and 5 are the time enabled map showing the progression of hurricanes and earthquakes in the United States.

Figure 4 This is the time enabled map showing the earthquake data. This is the whole time span so all the earthquakes in our data are being shown.

Figure 5 This is that same time enabled map only it is displaying the hurricanes. This is only a small chunk of the time as you see on the slider at the bottom of the image. 

Results

The results of this lab are the 5 figures I have included. They are all used to illustrate a different task in the lab and help us to better understand how to create and host geospatial services.  

Sources

Data sources: Dataset for part 1 section 1 is obtained from Mastering ArcGIS geodatabase by Maribeth Price, 2014. Data for part 1 section 3 is obtained from Wisconsin DNR, 2013. Stream dataset for part 1 section 4 is obtained from Mastering ArcGIS geodatabase by Maribeth Price, 2014 while the Lakes dataset is obtained from Wilson, Cyril unpublished data 2012. Data for part 2, section 1 is obtained from Advanced Remote Sensing Class, Fall 2012. Data for part 3 is obtained from Fu, Pinde (2015). HERE, Census at: \\EsriPress\GTKWebGIS\Chapter3\Data.gdb\Earthquakes, courtesy of USGS National Atlas. \\EsriPress\GTKWebGIS\Chapter3\Data.gdb\Hurricanes, courtesy of NOAA National Climatic Data Center.