Temporal profile charts allow you to visualize change over time using a multidimensional raster or a time-aware mosaic dataset. You can generate a chart for multiple locations, multiple variables, and multiple spectral bands. You can visualize and compare overall trends and statistics across locations.
To create a chart, right-click a multidimensional raster, multidimensional mosaic dataset, or mosaic dataset containing a time series of imagery in the Contents pane, point to Create Chart, and click Temporal Profile to open the Chart Properties pane.
Define the data settings for your chart on the Data tab in the Chart Properties pane.
There are several options for generating a temporal profile chart. The options available in the Time series drop-down menu depend on the layer for which you are generating a chart. For example, a multiband image dataset will only provide options to visualize spectral band information at one or more locations, or at one or more dimension values. The following options are available for a temporal profile chart:
- One location with multiple variables—Use this option to visualize changes for multiple variables at one location. You can compare the trends of multiple variables.
- Multiple locations with one variable—Use this option to visualize changes in a single variable at multiple locations. You can compare the variable trends across geographies. This is the default.
- One location with multiple bands—Use this option to visualize changes for multiple bands of a multiband image, at a single location. You can compare spectral changes for multiple bands.
- Multiple locations with one band—Use this option to visualize changes for a single band of a multiband image, at multiple locations. You can compare spectral changes across geographies.
- Multiple locations with multiple dimensions—This option works specifically on multidimensional data containing other dimensions in addition to time. The supported multidimensional layer types are multidimensional mosaic dataset, multidimensional raster layer, netCDF raster layer, and multidimensional image service. The temporal profile is created based on the specific values in other dimensions, such as depth at the corresponding time value. For example, the chart below shows ocean salinity values over time at one location, at depths of 2 meters and 80 meters below the surface. When the Time series parameter is set to Multiple locations with multiple dimensions, you must specify the variable you want to graph and the additional dimension you want to include.
You can also create a temporal profile chart for categorical raster data, for example, land cover over time. For categorical raster data, the only option is to create a single variable, multiple location chart, so the Time series parameter does not appear in the chart properties.
Select the field that represents the time dimension in your dataset using the Time parameter. For multidimensional datasets, the default value is the StdTime field. For nonmultidimensional data, you can choose any time field in your mosaic dataset.
Define an area of interest
You can use the Draw tool at the top of the Chart Properties pane to draw point features on the mosaic dataset, multidimensional raster layer, or .netCDF raster layer in the map view. These point features are added to the feature table in the Chart Properties pane. In the feature table, you can select or deselect the point features, remove unwanted point features, and edit the symbol and label for each point. Based on the selection from the feature table, once a time series is defined, the temporal profile for each location is created and displayed on the same dialog box.
Variables or Bands table
When generating a chart for single or multiple variables, you can select the variable to graph using the Variables table. When generating a chart for optical imagery, you can select the band to graph using the Bands table. The name of the table is contextual based on the data and the Time series selection.
The Variables or Bands table also allows you to specify the width of the line in the chart, and the label that appears in the chart legend and hover tips. If you are plotting multiple variables or bands in a single chart, you can also specify the color of the line for each variable or band. If you are plotting a single variable or band, the color of the line will match the color of the location marker in the Define an area of interest table.
To add a trend line to your temporal profile chart, check the box next to Show Trend Line. You can modify the color and width of the trend line. One trend line will be drawn for each location if charting multiple locations, or each variable if charting multiple variables.
The trend line can be linear or harmonic.
Time aggregation, or binning, occurs automatically when a date field is chosen for the x-axis. Several options control the interval size and related settings applied to the binning.
The Time Interval Size parameter defines the time interval on the x-axis. If the temporal data is in evenly spaced intervals, the data’s original temporal interval is used as the default. Therefore, no time aggregation is required to display the data, and the temporal profile will display the original pixel values without value aggregation.
When the temporal data is at unevenly spaced intervals, it is binned into time intervals along the x-axis. A default interval size is chosen based on the temporal extent of the dataset and can be manually changed through the Interval Size parameter.
The Time Aggregation parameter automatically changes to Mean when a new Interval Size value is specified. You can manually change Time Aggregation to Count, Mean, Median, or Sum.
You can also use Interval Size and Time Aggregation to perform statistical analysis on your data. For example, aggregate your hourly data to daily, monthly, or yearly time intervals and visualize the trend at different time scales. The value displayed on the temporal profile is calculated based on the values that fall within the new time interval and the Time Aggregation parameter.
The Spatial Aggregation parameter automatically changes to Mean when the area of interest is drawn using a polygon or line sketch tool. Other options are Minimum, Maximum, Median, or Sum.
The Interval alignment parameter and the Time incomplete interval parameter are used to specify how you want to align your data. For more information, see Interval alignment.
Specify whether you want to label the data points in your chart.
View the statistics for each location in your chart. The statistics are calculated by analyzing the pixel values for your areas of interest over time.
Define the axes settings for your chart on the Axes tab in the Chart Properties pane.
The temporal profile x-axis values are date or time values. The default date and time format displayed on the chart can be modified according to your preference. The date must always be displayed, but time can be removed from the x-axis display.
Default minimum and maximum y-axis bounds are set based on the range of data values represented on the axis. These values can be customized by entering a new y-axis bound value. Clicking the reset icon returns the y-axis bound to the default value.
By default, line chart axes are displayed on a linear scale. Numeric (nondate) axes can be displayed on a logarithmic scale by checking the Log axis check box.
You can format the way an axis will display numeric values by specifying a number format category or by defining a custom format string. For example, $#,### can be used as a custom format string to display currency values.
Guide lines or ranges can be added to charts as a reference or way to highlight significant y-axis values. To add a new guide, browse to the Guides tab in the Chart Properties pane, choose whether you want to draw a vertical or horizontal guide, and click Add guide. To draw a line, enter a Value where you want the line to draw. To create a range, enter a to value. You can optionally add text to your guide by specifying a Label.
Titles and description
Charts and axes are given default titles based on the variable names and chart type. These can be edited on the General tab in the Chart Properties pane. You can also provide a chart Description, which is a block of text that appears at the bottom of the chart window.
Create a temporal profile chart to visualize yearly soil moisture trends at two locations from 1948 to 2016.
- Create a temporal profile chart for a multidimensional raster layer containing monthly soil moisture.
- Set Time Series to Multiple locations with one variable.
- Create two point features on the map, and change the labels to Location 1 and Location 2.
- Set Time to Standard Time.
- Set Interval Size to 1 year.
- Set Time Aggregation to Mean.