Field Activity #8: ArcPad Data Collection

Introduction

This weeks activity involved gathering micro climate data using a Trimble GPS unit and temperature gauge, then mapping the information by using ArcMap.  The class was divided into groups of two and the task was to gather points in an area on the campus of University of Wisconsin Eau-Claire.  The activity called for collecting temperature, dew point, relative humidity, snow depth, wind direction, as North, South, East and West, and also azimuth 0-360 degrees, wind speed, time, and any notes to help better the collection.  After all the groups collected data for their area the points were compiled into one geodatabase ready to be used to map out the results.  

Methods

The first step of this activity is getting the GPS unit and ArcMap ready for the collection.  Two weeks ago, see field activity #6 blog, a domain was created for this assignment and was placed, along with a raster image of UWEC's campus into ArcMap.  To load the domain, or feature class, and raster image on to the GPS or ArcPad these steps need to be taken.  In ArcMap click on customize>extensions> and check ArcPad Data Manager, this will allow you to use that tool.  Next add the toolbar to ArcMap by clicking Customize>Tool bars> ArcPad Data Manager.  Then click the first button as figure 1 displays to start adding the data to the trimble unit.  

Figure 1: Click on Get Data for ArcPad

After clicking this button a box will appear and click next from the welcome screen.  Hit the action menu and choose all Geodatabase layers, and also click on the raster image and click export as background TIFF.  Then in the next screen under specify a name type 'micro_yourusername' this will create a folder for all the information.  Also change the path of where the file is stored by clicking on the little folder and put in the folder you wish to store the ArcPad data information.  Then in the next window click on create the ArcPad data on this computer and finish.  Once the project is created, copy the folder and paste it for backup in case there is an error in the process or out on the field.  

The next step is to put the new feature class and tiff image onto the ArcPad GPS unit.  Connect the trimble unit with a USB port, and once the Trimble unit is in the computer and files can be viewed copy and past the newly created folder into the storage card of the Trimble unit.  After this is done disconnect the trimble and click the button top right corner labeled ArcPad 10 as you can see in figure 2 below.  Next hit open new map and choose the new folder that created for this process, figure 3.

Figure 2: ArcPad 10

Figure 3: Choose new map to open

After these steps and with the raster image loaded to the device you are ready to go out into the field and collect data.  Using the Trimble GPS unit, figure 4, a compass, meter stick, and the Kestral device collecting the data should run quite smooth.

Figure 4: Trimble GPS unit.  When first turning on the trimble make sure the GPS is getting a signal or fix,
to allow for the GPS to know your exact location of the points created. 

Figure 5: Kestrel device, can read temperature, dew point, relative humidity, and wind speed.  

Once out in the field and in the study you and a partner can work as a team to collect the data quickly.  In trimble unit find the green circle button that collects a point and allows you to enter the information for temp, dew point, wind speed, etc.  Use the meter stick to measure snow depth, compass to find the wind azimuth and direction and the arrows on the kestrel unit will allow to move across the different elements of temperature.  Once collecting all the information move onto the next point, since this is a micro-climate activity it is wise to collect points that are relatively close to each other, about 20 or 30 yards.  

Figure 6: My partner and I study area and the 23 points we collected.  As you can see we collected
points on the eastern side of campus.  After looking at the points collected
we could have done a better job at collecting more points to gather more information. 

Figure 7: Image of UWEC's campus and the class's study area.  A total
of 268 points were collected. 

After enough points are collected the next step is to take the trimble unit back to the computer and upload the points on to ArcMap.  This is done by going back to the ArcPad Data Manager and clicking on the fourth button 'get data from ArcPad.  In the box hit the green plus arrow navigate to the new folder with points and click import graphics or check in. After this is done the new feature class containing the points with the micro climate information will appear in the geodatabase created for this activity.  The next step is to merge all of the groups information into one feature class so the information can be mapped.  The step for this can be found in Tim Condon's blog, a classmates of mine, found here.  

The next step of the activity is to create a series of map's that display the information collected.  This was done by adding the merged feature class of the all the groups.  Then using the feature class's symbology to display different types of information.  To create continuous maps of temperature, dew point, snow depth, and relative humidity the arc tool box > 3D analyst tools and the interpolation technique of natural neighbors was used to map the data.  Also one of the assignments was to create a map that showed the wind speed and direction this was done in symbology> quantities> graduated colors> advanced> rotation and rotating it by wind direction azimuth.  An arrow symbol was used to show the direction of the wind as you can see in figure 8 below.  

Results

Figure 8: Map of Wind Speed and Direction, the wind were rather calm on this day only 3 reaching
over 10 mph, also the wind direction seemed to trend as a NW wind ,coming from, making the temps colder.

Figure 9: Relative Humidity Map, increased from west to east.  

Figure 10: Snow Depth Map of the Snow depths on campus in centimeters.  The snow levels
were rather low unless some snow was shoveled or plowed making the levels higher

Figure 11: Temperature map of Eau Claire, this is an interesting map as the
only real high temps came in one circle, it could have been a group error or located near a
heater. 

Figure 12: Temperature and Relative Humidity Map, there seems to be no trend
between relative humidity and temperature.  

Figure 13: Map of temperature and wind speed + direction.

This map shows that colder temperatures are associated with higher wind speeds, which makes sense.  However there is a wind speed of 10-11 in the warmest spot which is interesting to me.  It makes me believe that there was a heater or error by the group collecting the data.  

All of the maps do a good job of representing the data collected and some patterns can be seen.  There were some errors by group 3 and points had to be deleted between Murray and Towers Hall.  Somehow the points got placed near the equator which is very strange.  These points were deleted to make the interpolation techniques work.  

Conclusion

I thought this activity was very fun to complete.  I enjoyed making the maps to find the results of all data collected and I am very happy of how my maps turned out.  I wish I would know more about weather so I can make connections and see patterns more easily.  For example, the relationship between temperature, dew point, and relative humidity and how they effect each other.  In all it was a great learning experience for the class and a skill that is going to be very useful for the future.