Field Activity 6: Microclimate Geodatabase Construction for Deployment to ArcPad

Introduction:

This week the class was assigned the task of creating a geodatabase to be deployed to ArcPad to create a microclimate map.  The microclimate map itself will be a part of a future activity; this week the class is just to focus on creating the geodatabase.  One might think of the construction of a geodatabase as a trivial task.  Though a geodatabase can be constructed rather easily thanks to ArcCatalog's user-friendly layout, setting up a geodatabase properly for data collection is another matter entirely.  This whole activity is pre-planning for a future activity, the better this activity goes, the better the activity out in the field will go.  Part One will cover the importance of pre-planning and having a proper geodatabase, while Part Two will be a tutorial in how the microclimate geodatabase was actually instructed.


Part One:

Being properly prepared is one of the keys to good field work.  If someone goes out into the field without the correct tools, the data collection will likely go horribly wrong.  ArcPad (Figure 1) is a good tool to use when collecting data out in the field.  It can be used to capture, edit, and display geographic information quickly on the go.  Data can be checked in and out of a geodatabase from ArcPad itself.

This is an example of a tool with ArcPad installed.  A geodatabase can be uploaded into this device and used to survey and collect data about features that can be created on the fly.  It's best to have the device properly set up for the most efficient and effective data collection. (Figure 1)

In order to effectively use ArcPad to collect data, a proper geodatabase should be installed.  A geodatabase is a common data storage and management framework when using ArcGIS.  It is a data repository that allows easy access and management of GIS data.

When creating a geodatabase, one must consider every aspect that the project may entail.  This is where a large amount of pre-planning comes in.  When pre-planning for geodatabase creation, one of the key aspects to consider is the domain.  Domains are a set or range of valid attribute values that can be recorded for features collected or updated in a specific field.  They are essential to ensure that data entry is accurate and consistent.  A single domain can be used for multiple feature classes within a geodatabase as the domain is a property of the geodatabase which can be set.  There are several different domain field types which can be set (Figure 2).  These include:  short integer, long integer, float, double, text, and date.

These are some of the Field Type options for domains.  Text is also an option when choosing a field type.  Typically short integer and float are the more popular of the options.  These are the only two options, other than text, which will be used when creating the geodatabase for the microclimate map. (Figure 2)

If someone wishes to go out and collect temperature data of an several points around an area (which will be done for the microclimate map) they will likely set their domain as a float with a reasonable temperature range (0-100 degrees Fahrenheit).  Setting this domain and range will help prevent them from accidentally recording a value such as 200 Fahrenheit as it will not be possible when using ArcPad.  Getting all of the domains properly set with appropriate ranges can help save time when entering in values and will help the user avoid errors when recording data.  Also doing all of this beforehand can help save time when out in the field.


Part Two:

Steps to Complete Proper Geodatabase Construction for a Microclimate Map:
1. Pre-planning for preparation of the geodatabase
2. Construction of the file geodatabase
3. Creation of geodatabase domains based on pre-planning
4. Construction of a feature class to be used to collect data
5. Preparing project in ArcMap

Step One:

In preparation of the geodatabase the project itself must be considered.  A microclimate is a small area that is different from the area around it.  It may vary in temperature, humidity, or in other aspects.  Microclimates can be very small.  For example, a courtyard next to a building will likely be warmer and less windy than an open area just 100 meters away.  Microclimates may also be very large.  For example, an urban area typically doesn't experience the harsh cold that areas in the surrounding countryside do.

A microclimate map is a good way to help visualize the various microclimates of a given area.  When collecting data to design a microclimate map, various aspects must be taken into consideration.  Temperature, wind speed, wind direction, relative humidity, dew point, time and date, and even snow depth are all information of interest that will need to be gathered to help design a microclimate map for the University of Wisconsin-Eau Claire campus.  All of these data will need to be taken into consideration when designing the geodatabase.

Step Two:

Constructing the geodatabase is one of the easier steps of the whole process.  One way to do this is to open up ArcCatalog, choose a folder to insert the geodatabase, right click and select "new" "file geodatabase" (Figure 3).

This shows what the new geodatabase will look like in ArcCatalog.  From here the geodatabase is ready to have its properties set. (Figure 3)

For this project, the new geodatabase was named "mc_condontd.gdb".  This is the geodatabase in which all data will be collected, stored, analyzed, and displayed from for the microclimate map. (Figure 4)

Step Three:

When setting geodatabase domains, it is important to consider all aspects of data that may be collected; for the project as it is easier to prepare the domains initially than to go back once collection has begun.  In the case of this microclimate map, several domains were set based on the pre-planning in step one.  To set the domains, one simply needs to right click on the geodatabase and click on "properties".  From here clicking on the Domains tab will allow domains and ranges to be set (Figure 5).

This is the domains tab underneath the geodatabase properties.  From here, the domains and ranges can be set to the desired field types and values.  Multiple different domains can be set and domains can be used multiple times or not at all in the creation of feature classes which will be explained further on in this report. (Figure 5)

Looking at the data that will be collected will help determine what domains and ranges to be set.  Temperature in Fahrenheit will be one of the main aspects of the map.  Numerical data will be collected and the temperature will likely be greater than zero and less than one hundred.  Also, fractions will likely need to be collected as well.  Therefore the field type will be set at float with a range of 0-100.  Another piece of information that will be of interest for the microclimate map is dew point (Figure 6).  The dew point will be collected using decimals and will likely be no lower than -20 and no higher than 100; as can be seen in Figure 6, the domain and range have been set accordingly.

The domain and range are set for every different bit of information.  The way it is set depends on the conditions and what should be recorded.  For example, the notes domain is set to a text field type, this means that text can be entered when notes are entered in the field. (Figure 6)

Step Four:

Once proper domains have been created for all of the information that will be collected a feature class can be created.  Feature classes are collections of features with each having a spatial representation such as a point, line, or polygon (Figure 7) and having a common set of attribute columns.

This image shows the different ways a feature class can be represented.  In the case of the microclimate map only one feature will need to be created and it will be a point feature class. (Figure 7)

A feature class can be created in the geodatabase by navigating to the inside of the geodatabase, right clicking, and selecting create new feature class. From here point feature class should be selected and the proper projection should be selected (UTM zone 15 in this case).  After these two options are selected the option to create attribute field names will pop up (Figure 8).  A feature class can have many attributes, this is why only one feature class is being created to create the microclimate map.

This is the menu in which the attributes can be added to the feature class.  Once the attributes are added (ie Temperature), a domain that was previously created can be set.  This is why it is important to have the domains set before creating the feature class. (Figure 8)

Each attribute that was created was matched with the proper domain to help insure against mistakes being made in recording the data, and to help speed up the data recording process.  For example, the snow depth attribute field uses the snow depth domain (Figure 9).

Each attribute field was matched to a domain that was previously designed in the geodatabase.  Because snow depth is matched to the snow depth domain, the values that are recorded have to be between 0 and 36 as snow depth will be measure in inches. (Figure 9)

This is inside of the mc_condon geodatabase.  The mc_points is the created feature class that contains all of the relevant attributes with their domains.  The EC6 is a raster aerial image of Eau Claire that was imported from a separate folder and will be used for the final map. (Figure 10)

Step Five:

From here ArcMap can be opened and the EC6 raster and mc_points can be brought into the layers (Figure 11).  Saving this as a project for the future helps prepare the project to be put into ArcPad in future weeks when the microclimate map is created.

This shows the contents of the geodatabase put into ArcMap.  The mc_points obviously has no features as nothing has been gathered yet. (Figure 11)

Conclusion:

Creating a geodatabase can be an easy task.  However, this task needs to be performed well in order to ensure successful field work.  This is all a part of pre-planning for a project.  Domains can be put into a geodatabase to help combat human error and extrapolate the process of data collection.  This is best done before going out into the field.  In fact, it's best done before creating feature classes.  Many times only one feature class is required, as it can contain many different attributes and is more interesting to analyze the more information it has.  This also helps prevent needing to gather many different features for one location.  If everything has been planned out well before hand, data collection can go smoothly and be a simple process.