Map Arctic ice extent

The data that you'll use for this map is available from ArcGIS Living Atlas of the World. You'll choose a polar projection for your map and reproject the data to match. You'll spend some time exploring the data to understand its attributes, then you'll choose symbology to highlight the story of sea ice decline. Finally, you'll symbolize some base data so you can show the ice data in context.

Choose a map projection

You'll begin your map by adding Arctic sea ice data and choosing a projection that suits the polar region and your map's purpose.

  1. Start ArcGIS Pro. If prompted, sign in using your licensed ArcGIS account.
    Note:

    If you don't have ArcGIS Pro or an ArcGIS account, you can sign up for an ArcGIS free trial.

  2. Under New Project, click Map.

    New Map template button

  3. In the Create a New Project window, for Name, type Arctic sea ice. Optionally, choose a new location for your project. Click OK.

    A map appears.

  4. On the ribbon, click the View tab. In the Windows group, click Reset Panes and click Reset Panes for Mapping (Default).

    Reset Panes for Mapping

    This ensures that the Contents and Catalog panes are open and that other panes are closed. You'll use the Catalog pane to find the data you need for your map.

  5. In the Catalog pane, click the Portal tab and click the Living Atlas tab.

    Portal and Living Atlas tabs

  6. Search for Arctic Sea Ice Extent. In the search results, right-click the Arctic Sea Ice Extent feature layer and click Add To Current Map.

    Add To Current Map

    Note:

    If you are unable to access the Arctic Sea Ice Extent layer from ArcGIS Living Atlas, download and unzip the ArcticSeaIceExtent geodatabase.

    New data appears on the map, representing monthly ice extents for the Arctic since 1978. This data is from the National Snow and Ice Data Center, through ArcGIS Living Atlas of the World.

    Map with Arctic sea ice data

    The map's projection has also changed. In ArcGIS Pro, the map's default coordinate system is determined by the first layer (excluding basemaps) that is added. You'll find out which coordinate system the data uses and decide whether it's the one you want for your map.

  7. In the Contents pane, right-click Map and click Properties.

    The Map Properties window appears.

  8. In the Map Properties window, click the Coordinate Systems tab.

    Coordinate Systems tab in the Map Properties pane

    The Current XY button tells you that the map's current coordinate system is WGS 1984 EPSG Alaska Polar Stereographic. Stereographic projections are common for polar regions, but they do not preserve area. Your map will provide a visual comparison between areas of ice cover, so you should use an equal-area projection.

  9. In the search bar, type North Pole and press Enter.
  10. In the XY Coordinate Systems Available list, click the arrow next to Projected Coordinate System to expand it. Expand Polar. Click North Pole Lambert Azimuthal Equal Area.

    North Pole Lambert Azimuthal Equal Area coordinate system selected in the Map Properties pane.

    The Current XY button updates to the selected projected coordinate system.

  11. Click OK.

    The map redraws. This time the Bering Strait, between Alaska and Russia, is at the top of the map.

    Map with new projection

    Note:

    You can learn more about choosing appropriate projections in the lesson Choose the right projection.

Copy and reproject the data

Next, you'll create a local copy of the data so you can reproject it into the same coordinate system as the map. You may need to use spatial analysis tools later to understand or visualize your data, and if you do, keeping the coordinate system consistent will be important to ensure consistent results. Additionally, ArcGIS Pro will perform a little faster if the data and the map use the same coordinate system.

Before creating a copy of the data, you'll ensure that all of the data is visible and available for copying.

  1. In the Contents pane, right-click Arctic Sea Ice Extent. Click Data Design and click Fields.

    Fields option within the Data Design menu

    The Fields table appears. All of the data's fields are listed here. The Visible column shows that only one field is currently visible. Only visible fields can be copied.

  2. Click the header of the Visible column twice to check all rows.

    Header of the Visible column in the Fields table

  3. On the ribbon, on the Fields tab, in the Changes group, click Save. Close the Fields view.

    Save button on the Fields tab of the ribbon

    Now that all of the attributes are visible, you'll make a local copy of the layer. The current layer is a service layer, stored online. It's also a live-feed layer, receiving new data updates every month. When you save a local copy on your computer, the new layer will no longer receive updates, but you will have more control over the layer. For example, you can change its coordinate system.

  4. On the ribbon, on the View tab, in the Windows group, click Geoprocessing.

    Geoprocessing button on the View tab of the ribbon

  5. In the Geoprocessing pane, search for Copy Features. In the search results, click Copy Features to open the tool.

    Copy Features tool in the Geoprocessing pane

  6. For Input Features, choose Arctic Sea Ice Extent. For Output Feature Class, delete the existing text and type IceExtent.

    Parameters for the Copy Features tool

    You were able to remove the path because, by default, any new data created by geoprocessing tools is stored in the project's geodatabase (Arctic sea ice extent.gdb).

    You'll ensure that the output of the Copy Features tool is reprojected into the map's coordinate system.

  7. Click the Environments tab. For Output Coordinate System, choose Current Map [Map].

    Environments tab and Output Coordinate System set to Current Map.

    Note:

    Setting an Output Coordinate System is the same as running the Project geoprocessing tool after running the Copy Features tool.

  8. Click Run.

    Because the dataset is large, the tool may take a few minutes to run. When it finishes, a layer named IceExtent is added to the Contents pane.

  9. In the Contents pane, right-click Arctic Sea Ice Extent and click Remove.

    Remove option in the layer context menu

    You'll also remove the basemap layers, since they are not designed for mapping polar regions. You'll replace them with other background layers later.

  10. Remove World Topographic Map and World Hillshade (or other basemap layers).
  11. On the Quick Access Toolbar, click Save to save the project.

    Save button on the Quick Access Toolbar

Understand the data

Your goal is to create an effective visualization of this dataset, however, that is difficult to do until you understand the dataset. You'll take some time to explore its attributes, properties, and patterns before you design symbols. You'll explore the attribute table, create a chart, and choose a meaningful subset of the data on which to focus your visualization.

  1. In the Contents pane, right-click IceExtent and click Attribute Table.

    The layer's attribute table appears below the map.

  2. Examine the fields in the attribute table.

    IceExtent attribute table

    The Year and Month fields tell you that this layer has one feature for each month since November 1978. The Area and Extent fields both have values in million square kilometers. Often, field names are not enough to explain the data, and more research is needed. You found an explanation of the difference between sea ice area and extent on the National Snow and Ice Data Center's website. Ice extent includes any area with at least 15 percent ice cover. Extent is more commonly used than area to account for the difficulty in distinguishing between open water and meltwater on top of ice in satellite imagery.

    The name of the original layer (Arctic Sea Ice Extent) tells you that the polygons represent the Extent field, rather than the Area field.

    Note:

    You could also compare the automatically generated Shape_Area field. Its values (in square meters, determined by the unit of the coordinate system) are closer to the values in the Extent field than the Area field, but not exactly the same. If you consult the layer's metadata, you will learn that a smoothing algorithm was applied to the original data, which can account for the difference between the Shape_Area and Extent values.

  3. Close the attribute table.

    There's a time slider at the top of the Map view, indicating that this layer is time-enabled. Animation is a good method for showing this data, but you're making a static map, so you won't have this option. You'll disable the time property.

  4. In the Contents pane, right-click IceExtent and click Properties.
  5. Click the Time tab. For Layer Time, choose No Time.

    Time set to No Time in the Layer Properties window.

  6. Click OK.

    The time slider disappears.

    There are many overlapping features in this layer—perhaps too many to be able to see and understand all in one image. You'll need to focus on showing the important patterns present in the data. Next, you'll make a chart to better understand these patterns.

  7. Right-click IceExtent, point to Create Chart, and click Line Chart.

    An empty chart view and the Chart Properties pane appear.

  8. In the Chart Properties pane, for Date or Number, choose Year.
  9. For Numeric field(s), click the Select button and check Extent (million km2). Click Apply.

    Extent selected in the Numeric field(s) list.

    A chart appears. It shows a general downward trend. There is a large jump at the start of the chart, and possibly another jump at the end. This is because the first and last years do not contain all months.

    Line chart

    Note:

    The latest available month in your data will depend on when you copied it from the live-feed layer.

    For a clearer picture, you'll show each month as its own line.

  10. In the Chart Properties pane, for Split by (optional), choose Month. In the Chart properties warning window, click Yes.

    The chart now shows 12 lines, all of them descending.

    Line chart with 12 lines

    The chart tells you that February and March consistently have the largest ice extents while September (9) consistently has the smallest. In September, all of the summer's melting has completed and the winter's freezing has not yet begun.

    One of the best methods for communicating the story of a large dataset is to display only a small subset of the data. The challenge to this method is in choosing a meaningful subset. For this map, you'll only map September ice extent. September is the most dramatic month to show, since it contains the smallest extents and shows most clearly the approach of an ice-free Arctic Ocean. September may also be the most meaningful month to show, since only ice that persists through September becomes multiyear ice, which is more resilient to melting. A smaller September ice extent means a weaker ice pack for the coming winter.

  11. In the Contents pane, double-click IceExtent to open its Layer Properties window.
  12. Click the Definition Query tab and click New definition query.

    New definition query button in the Layer Properties window

  13. For Where, choose Month. Leave the second menu set to is equal to. In the third menu, choose 9.

    Definition query Where Month is equal to 9

  14. Click Apply and click OK.

    The chart filters to only show the 9 line.

    Line chart for September only

    You'll return to the chart later. For now, you'll close it so you can focus on the map.

  15. Close the chart and the Chart Properties pane.

    The map has also filtered to show a smaller and more compact group of features.

    Map of September ice extents

Symbolize the ice data

Now that you've chosen a meaningful subset of the dataset (September), you'll symbolize it to show areas that are more often or more rarely covered in ice.

  1. In the Contents pane, right-click IceExtent and click Symbology.

    The Symbology pane appears. You'll choose quantitative symbols to depict change over time.

  2. In the Symbology pane, for Primary symbology, choose Graduated Colors.

    Graduated Colors

    This map shows you the last year when any area has been ice-covered. Yellow areas haven't been ice-covered in several decades. Red areas have been ice-covered in recent years. This symbolization would work well if the decline of sea ice was a steady phenomenon, but it's not: some recent years have seen more ice than some earlier years. This overlap means that much of the story is obscured.

    Instead of mapping the most recent year to be ice-covered, you'll map how often each area has been ice-covered. You can determine this using the Count Overlapping Features tool.

  3. Below the Symbology pane, click the Geoprocessing tab to open the Geoprocessing pane.

    Geoprocessing tab below other panes

    Tip:

    If there is no Geoprocessing tab, on the ribbon, click the View tab. In the Windows group, click Geoprocessing.

  4. At the top of the Geoprocessing pane, click the Back button twice, or until a search bar appears.
  5. Search for and open the Count Overlapping Features tool.
  6. For Input Features, choose IceExtent. For Output Feature Class, type IceExtent_Overlap.

    Count Overlapping Features tool

  7. Click Run.

    The tool may take several minutes to run.

  8. In the Contents pane, uncheck the box next to the IceExtent layer to turn it off.

    IceExtent layer unchecked

    The new layer shows bands of color. The white areas on the edge have only been ice-covered in September a few years since 1979. The dark blue areas in the center have almost always been ice-covered.

    Ice extent data symbolized with bands of blue.

    You'll change the symbology to a method that can map this transition with a smoother gradient.

  9. In the Contents pane, click IceExtent_Overlap to select this layer. Open the Symbology pane.
    Tip:

    The Symbology pane will always display properties for the selected layer.

  10. For Primary symbology, choose Unclassed Colors. Ensure that Field is set to COUNT_.

    Symbology pane set to Unclassed Colors.

    A warning appears at the top of the Symbology pane. It says Maximum sample size reached. Not all records are being used to classify data. This means that the minimum and maximum values that were used to create the symbology may not be correct. The legend in the Contents pane shows a color ramp ranging from 1 to 7. You know that there's more than 40 years of data, so you expect the maximum number to be at least 40.

  11. At the top of the Symbology pane, click the Advanced symbology options tab and expand Sample size.

    Sample size on the Advanced symbology options tab

    The Maximum sample size is set to 10,000. This means that only the first 10,000 records of your layer were sampled. You'll change this number to one that's large enough to encompass your entire dataset.

  12. In the Contents pane, right-click IceExtent_Overlap, point to Selection and click Select All.

    Below the Map view, the Zoom to selected features button tells you that there are more than 50,000 features in the layer.

    55,936 selected features

    Note:

    Your map may show a different number of selected features. This is expected, since you copied the live-feed data on a different date.

  13. In the Symbology pane, for Maximum sample size, type a number larger than your selected features number. Press Enter.

    Maximum sample size set to 60,000.

    The warning message disappears. The legend in the Contents pane now shows a larger value range.

  14. Right-click anywhere on the map and click Clear.
  15. In the Symbology pane, click the Primary symbology tab.

    Primary symbology tab

    You'll reverse the color scheme so areas still covered in ice are white and areas where the ice has retreated and left open ocean are blue.

  16. Above the histogram, click the More button and click Reverse color scheme.

    Reverse color scheme in the More menu

    You'll also remove the gray outlines, which obscure the data.

  17. Next to Template, click the symbol.

    Template symbol

  18. If necessary, click the Properties tab and click the Symbol tab. Change Outline width to 0 pt.

    Outline width set to 0 pt.

  19. Click Apply.

    The map shows a smooth gradation from white to blue, mimicking melting ice.

    Map of Arctic sea ice symbolized with blue and white color scheme.

Symbolize the base data

Next, you'll add and symbolize base data. The symbology of your thematic data (in this case, the ice extent data) will only be clear and effective if the background data is designed to complement and promote it. You'll make symbology choices for the base data that give it a lower visual hierarchy than the thematic data: you will make the base data appear to sit in the background of the map.

  1. Download the IceMapData geodatabase and unzip it to a location on your computer, for example, your C:\ drive.

    This geodatabase contains base data for your map. The data is from Esri and Natural Earth. You can find the original sources for each of the layers on the item details page.

  2. On the ribbon, click the Map tab. In the Layer group, click Add Data.
  3. In the Add Data window, browse to IceMapData.gdb. Click ArcticCircle. Hold the Shift key and click NorthernMarineRegions to select all four feature classes. Click OK.

    Four layers selected in the Add Data window.

    Four layers are added to the map.

  4. In the Contents pane, turn off the NorthernMarineRegions layer.

    You'll use this layer later to create labels.

  5. Click the symbol for the Countries layer.

    Countries layer symbol

    The Symbology pane appears. You'll create a custom color for this layer.

  6. In the Symbology pane, on the Symbol tab, click the Color menu and click Color Properties.

    Color Properties

  7. In the Color Editor window, for Hex #, type F8EBCE and press Enter.

    HEX # set to F8EBCE.

    The Current color preview updates to a pale beige color. You'll save this color to your favorites style, where it will be easy to access later.

  8. Click Save color to style. In the Save Color As window, for Name, type Land. Click OK and click OK.
  9. In the Symbology pane, change Outline width to 0 pt.

    Outline width set to 0 pt.

  10. Click Apply.
  11. In the Contents pane, click the symbol for the ArcticCircle layer.

    ArcticCircle line

  12. In the Symbology pane, click the Gallery tab. Search for Marker only and click the Marker Only dotted line symbol.

    Marker Only symbol in the Gallery

    Dotted and dashed lines are often used in maps for nonphysical lines such as borders (as opposed to physical lines such as roads and rivers). Next, you'll choose a color that has low contrast with the land color. This will ensure that the ArcticCircle line is visible but not prominent.

  13. Click the Properties tab. For Color, choose Tecate Dust. (Point to colors to read their names.)

    Tecate Dust color

  14. Click Apply.
  15. In the Contents pane, right-click the symbol for the Graticule layer. Under Favorites, click Land.

    Land color in the Favorites list

    The graticule lines are only visible against the ocean, not the land. They look good against the white of the ice data, converging to show the location of the north pole, but they are too prominent against the blue ice data. They distract attention away from the map's theme.

    Map with graticule lines covering ice data

    You'll use a blend mode to ensure that the lines are still visible against the white areas but not against the blue areas.

  16. With the Graticule layer selected, on the ribbon, click the Feature Layer tab. In the Effects group, for Layer Blend, choose Darken.

    Layer Blend set to Darken on the Appearance tab of the ribbon

    The Darken blend mode ensures that the layer only draws on top of colors that are lighter than itself.

    Map with graticule lines partially covering ice data

Create a background layer

The background of your map is white, which might be confused with the white color in the ice layer. You'll create a background layer to symbolize the ocean.

  1. On the ribbon, click the Insert tab. In the Layer Templates group, click the expander button.

    Expander button for the Layer Templates gallery

  2. Click Polygon Map Notes.

    A new layer is added to the Contents pane. It is empty. You'll add a new feature to this layer.

  3. On the ribbon, click the Edit tab. In the Snapping group, click the bottom part of the Snapping button. Make sure that Snapping is On and Endpoint snaps to the nearest start or endpoint of a polyline feature are both highlighted in blue.

    Snapping button and menu

  4. On the ribbon, in the Features group, click Create.
  5. In the Create Features pane, click Polygon Notes. Click the Circle template.

    Circle template in the Create Features pane

  6. On the map, point to the north pole. When the snapping label reads Graticule : Endpoint, click the map.

    Snapping for Graticule : Endpoint

  7. Zoom out until you can see the entire world. Click the map near Antarctica but do not click outside of the map's circle.

    Map of entire world with new feature ending before Antarctica

  8. On the ribbon, in the Selection group, click Clear. In the Manage Edits group, click Save. In the Save Edits window, click Yes.
  9. Close the Create Features pane.
    Note:

    It's possible to change the background color of the map in the Map Properties window. You created a new layer instead because it offers more flexibility that will be useful later in the lesson.

  10. In the Contents pane, click Polygon Notes twice to make its name editable. Rename the layer Ocean.

    Ocean layer in the Contents pane

  11. If necessary, expand the Ocean layer. Right-click the layer's symbol and click Color Properties.

    You'll choose a lighter version of the beige land color for the ocean. This will result in a very low contrast between the land and ocean, helping both layers to have low visual hierarchy and appear as background information.

  12. In the Color Editor window, change Transparency to 0 percent. For Hex #, type FBF4E5. Click OK.

    Transparency set to 0 percent and HEX # set to FBF4E5.

  13. In the Contents pane, drag and drop Countries above Ocean. Drag and drop IceExtent_Overlap above Countries. Ensure that Graticule and ArcticCircle are at the top of the layer list.

    Map and Contents pane

  14. Save the project.

You have mapped Arctic sea ice extent for each September since 1979. You reprojected and explored the data, chose an appropriate subset of the data to display, and designed symbology for both the thematic and base data.


Refine the symbology

Now that both the thematic and base data have been symbolized, you can assess how well they are working. You created an effective visual hierarchy, with the blue rim of disappearing ice standing out as the most prominent part of the map. The light warm background colors are not typical for maps of the Arctic, but they help to emphasize that this is a map of summertime ice extents. In the summer, the Arctic has 24 hours of sunlight.

The map is attractive, but there are two aspects of the symbology that are not effective. First, the change over time is not clear. Second, the map appears calming. You were hoping to convey that disappearing sea ice is an alarming phenomenon. Next, you'll refine the symbology to address these concerns.

Make a custom color scheme

Colors have different connotations in different cultures, but blue is often associated with positive emotions such as trust, calm, and serenity. You'll change the naturalistic white and blue color scheme for one that feels more unnatural.

  1. If necessary, reopen Arctic sea ice.aprx in ArcGIS Pro.
  2. Open the Symbology pane for the IceExtent_Overlap layer.

    You'll create a custom color scheme with warm colors that reflect the theme of global warming. You'll start with a simple color scheme that is easy to edit.

  3. Click the Color scheme menu and choose Black to White. (Point to color schemes to read their names.)

    Black to White color scheme

  4. Click the Color scheme menu again and click Format color scheme.
  5. In the Color Scheme Editor window, click the black color stop. Click the Color menu.

    Black color stop in the Color Scheme Editor

  6. Click Color Properties. For Hex #, type C30084 and press Enter.

    HEX # set to C30084 in the Color Editor window.

    This pink color will have high contrast with the beige background and will be useful later in the map, so you'll save it to your favorites style.

  7. Click Save color to style. For Name, type Melt. Click OK twice.

    The color scheme now ranges from pink to white. You'll test it on the map before making further changes.

  8. In the Color Scheme Editor window, click OK.

    Map with pink to white color scheme

    The map looks less calming and more like a spreading disease. However, you can improve this color scheme further by adding a second hue. This will give the color scheme greater depth, allowing it to show more detail.

  9. In the Symbology pane, click the pink color scheme and click Format color scheme to reopen the Color Scheme Editor window.
  10. At the top of the Color Scheme Editor window, click the Add color button.

    Add color button

    Tip:

    If the Add color button is unavailable, click the white color stop.

    When you add a new color to a color scheme, it's easy to break the smooth transition from light to dark, which is important to help people understand the data. You'll choose a color that is darker than the light color stop (white) and lighter than the dark one (pink).

  11. Change the middle color stop to a custom orange color with a Hex value of FFD37F.

    Middle orange color stop

    Despite your efforts, the color scheme has lost its smooth transition; now there is too much color variety.

  12. Ensure that the orange color stop is selected.

    This also selects the darker half of the color scheme. The strong red color in the middle of this range is causing the color scheme to lose its balance. The pink color at the far end should be the darkest and the most visually prominent, not the red.

    Sometimes, this problem can be resolved by trying a different color algorithm.

  13. Change Algorithm to CIE Lab.

    Middle orange color stop with Algorithm set to CIE Lab

    The transition from pink to orange changes to one that is more gradual. Next, you'll remove the pale pink color between the orange and white color stops.

  14. Click the white color stop and change Algorithm to Linear.

    White color stop with Algorithm set to Linear

    You have now achieved a smooth light-to-dark color scheme. You'll make one more change. The transition between pink and orange is more varied and interesting than the one between orange and white. You'll stretch the interesting part out so it takes up more space on the color scheme.

  15. Click the orange color stop and change Position to 75 percent.

    Orange color stop with Position set to 75 percent

  16. Click Save to a style. For Name, type Ice Melt. Click OK twice.

    Map with pink, orange, and white color scheme

    Choosing and creating color schemes with a clear transition from light to dark makes the map easier for everyone to read, however, it's especially important to allow people with color blindness to read your map.

    Note:

    You can take screen shots of your color schemes or maps and test them with this Color Blindness Simulator.

Convert polygons to raster

The ice layer refreshes on the map every time you pan or zoom. Because it is a large file, the refresh might not be very fast, slowing you down as you work to design the rest of the map. You'll convert the polygons to a raster layer so it can draw faster on the map.

  1. Open the Geoprocessing pane. Search for and open the Polygon to Raster tool.
  2. For Input Features, choose IceExtent_Overlap. For Value field, choose COUNT_.

    This will ensure that the cell values of the raster will match the values in the COUNT_ field. If you choose a different field, you won't be able to match the symbology properly.

  3. For Output Raster Dataset, type IceExtent_Raster. For Cellsize, type 2000.

    A higher cell size will result in a raster that is too pixelated for your map.

    Polygon to Raster tool

  4. Click Run.
  5. In the Contents pane, drag the IceExtent_Raster layer above the IceExtent_Overlap layer.
  6. Open the Symbology pane for the IceExtent_Raster layer.
  7. Change the Color scheme to Ice Melt. Change Stretch type to Minimum Maximum.

    Raster symbology

    This Stretch type will ensure that the color scheme will be applied evenly to the full range of COUNT_ values. The raster layer now looks exactly like the polygon layer.

  8. In the Contents pane, right-click IceExtent_Overlap and click Remove.

Symbolize index lines

Your map conveys how often ice has covered each area in the month of September since 1979. Many people may assume that older years had larger ice extents and recent years had small ones, but the map doesn't provide any evidence of this trend.

Arctic sea ice has declined since 1979, and it's important for your map to convey that message. You'll draw the outlines of a few index years on the map to help tell this story.

  1. In the Contents pane, right-click IceExtent and click Copy. Right-click Map and click Paste.

    Paste in the Map context menu

    You now have two identical layers named IceExtent.

    Tip:

    You can also duplicate layers by holding the Ctrl key and dragging the layer.

  2. Rename the top IceExtent layer as Index years.
  3. Turn on the Index years layer and open its Symbology pane.
  4. For Primary symbology, choose Single Symbol. Click the Symbol.

    Primary symbology set to Single Symbol.

  5. If necessary, click the Properties tab and the Symbol tab.
  6. For Color, choose No color. For Outline color, choose Tecate Dust.

    Color and Outline color

  7. Click Apply.

    The map shows the outline of every September ice extent since 1979.

    Map covered with gold lines

    It looks pretty, but it's too much information to interpret. You'll filter this layer to only show three years.

  8. In the Contents pane, double-click Index years to open its Layer Properties window.
  9. On the Definition Query tab, next to Query 1, click Edit.

    Edit button on Query 1

  10. Click Add Clause.
  11. Build a clause with the following pieces:
    • For the first menu, choose And.
    • For the second menu, choose Year.
    • For the third menu, choose includes the value(s).
    • For the fourth menu, type 1980,2000,2020.

    Second clause in Query 1

  12. Click Apply. Click OK.

    Only a few lines draw on the map, giving an appearance similar to contour lines on a topographic map. The lines are difficult to see over some of the yellow and orange colors. You'll solve this problem with a layer blend.

    Map with only three index lines

  13. With the Index years layer selected, on the ribbon, click the Feature Layer tab. In the Effects group, change Layer Blend to Linear Burn.

    Now all lines appear darker than the colors underneath.

  14. Save the project.

    Map with index lines and blend mode

You made a custom color scheme to change the tone of the map and associate it with the theme of global warming. You also added index lines to map the retreat of summer ice over time. You'll add more elements later to help emphasize this point.


Label the map

Next, you'll label the Index years layer so map readers will know what each line represents. You'll also label the larger seas to provide geographic context. You'll convert the labels to annotation so you can have more control over their placement.

Create labels

You'll create labels for two layers. You'll write a labeling expression and adjust labeling properties.

  1. If necessary, reopen Arctic sea ice.aprx in ArcGIS Pro.
  2. In the Contents pane, right-click Index years and click Label. Right-click Index years again and click Labeling Properties.

    The Label Class pane appears. You'll write an Arcade expression so the labels can convey information from two fields at once: the year and the extent in million square kilometers.

  3. If necessary, in the Label Class pane, click the Class tab and click the Label expression tab.

    Class and Label expression tabs

  4. In the Expression box, delete the existing text and type or copy and paste $feature.Rec_Year + TextFormatting.NewLine + $feature.Rec_Extent. Click Apply.

    Expression box and Apply button

    The labels show the year on the top line and the extent on the bottom line. You'll modify the expression to round the extent number and to add text for the unit.

    Three stacked labels on the map

  5. In the Expression box, delete $feature.Rec_Extent and type or copy and paste Round($feature.Rec_Extent,2) + " million km2". Click Apply.

    New expression and resulting labels

    The labels are now clearer to understand. You'll change their appearance to better match the warm colors of your map.

  6. In the Label Class pane, click the Symbol tab. Expand Appearance and change the following properties:
    • For Font name, choose Corbel.
    • For Font style, choose Bold Italic.
    • For Size, choose 10 pt.
    • For Color, choose Tecate Dust.

    Symbol properties

    Note:

    If you don't have the Corbel font installed on your computer, choose any other font.

    Tecate Dust is a good color for lines on the map, but it may be too light for text. You'll create a slightly darker version of this color to ensure legible labels.

  7. Click the Color menu again and click Color Properties. In the Color Editor window, change Color Mode to HSL.

    Color Mode set to HSL in the Color Editor window.

    HSL stands for Hue, Saturation, and Lightness. This color model is useful for mixing colors that are similar to existing colors. You will use it to create a color that is perceptibly the same hue and saturation as Tecate Dust, only darker.

  8. Change Lightness to 60 percent and press Enter.

    Lightness set to 60 percent.

  9. Click Save color to style. For Name, type Text. Click OK twice.
  10. In the Symbology pane, click Apply.

    You can save entire symbols to your Favorites style, in addition to colors. Next, you'll save the text symbol, which includes its color and other font properties, so it can be reused later in other parts of the map.

  11. Click the Menu button and click Save symbol to style.

    Save symbol to style

  12. For Name, type Gold. Click OK.

    On the map, the labels are stacked into three lines. This feels unnatural since the third line contains the unit descriptor for the second line. You'll adjust the stacking property.

  13. In the Label Class pane, click the Position tab and the Fitting Strategy tab. Expand Stack and uncheck Stack label.

    Stack label unchecked

    The labels now stack over two lines instead of three. The expression you wrote earlier contained the constant TextFormatting.NewLine, which forces a new line after the Year field, regardless of labeling properties.

    Map with finished labels

    The labels are all positioned in the middle of the Arctic Ocean. You'll adjust their position later. First, you'll label the larger seas in your map's area.

  14. In the Contents pane, turn on the NorthernMarineRegions layer. If necessary, drag and drop it above the IceExtent_Raster layer.
  15. Right-click the symbol for NorthernMarineRegions and click No color.

    Symbol for the NorthernMarineRegions layer

    The outline of the layer is still visible. You'll use these lines as guides for labeling and remove them from the map later.

  16. With the NorthernMarineRegions layer selected, on the ribbon, click the Labeling tab. In the Layer group, click Label.

    Label button on the Labeling tab of the ribbon

  17. In the Text Symbol group, click Gold.

    Gold text symbol

    Labels appear on the map. You'll adjust their stacking properties so they stack as much as possible. This will make them more compact and easier to place in tight spaces.

  18. In the Label Class pane, on the Position tab, on the Fitting Strategy tab, in the Stacking separators box, check the first Forced split box.

    Forced split box checked

    There are more labels on this map than are needed to provide geographic context. You'll remove the labels for smaller areas.

  19. Click the Conflict resolution tab. Expand Minimum feature size. In the middle menu, type 3,000,000. Leave the other menus set to Perimeter and Map units.

    Minimum feature size set to a 3,000,000 map units perimeter.

    Now, only the larger seas are labeled.

    Map with marine region borders and labels

  20. Close the Label Class pane.

Convert labels to annotation

In ArcGIS, labeling is an automated process, controlled by labeling properties. If you require more control over the position or appearance of individual labels, you can convert them to annotation. You'll convert the labels in this map to annotation and reposition some of them.

  1. Zoom out on the map until you can see the entire Arctic circle.

    Only labels currently in view will be converted to annotation.

  2. In the Contents pane, right-click Ocean and click Label to ensure that labeling is turned off for this layer.

    Label in the Ocean layer's context menu

  3. On the ribbon, click the Map tab, in the Labeling group, click the bottom part of the Convert button and click Convert Labels To Annotation.

    Convert Labels To Annotation

  4. In the Convert Labels to Annotation pane, for Conversion Scale, type 22,000,000 and press Enter.

    This will be the scale of the map in your layout later.

  5. Ensure that Convert is set to All layers in map.
  6. For Output Geodatabase, click the Browse button and choose Arctic sea ice.gdb. Click OK.
  7. For the remaining properties, accept the defaults.

    Convert Labels To Annotation tool

  8. Click Run.
  9. Close the Geoprocessing pane.

    Labeling has been turned off for your map layers. A new group layer, named GroupAnno, is added to the Contents pane. It contains two annotation feature classes. These are similar to feature classes—they have attribute tables and they can be modified with layer properties.

    You'll use a blend mode to give the annotation features the same appearance as the Index years layer.

  10. In the Contents pane, ensure that GroupAnno is selected. On the ribbon, click the Group Layer tab.
  11. In the Effects group, change Layer Blend to Linear Burn.

    Layer Blend set to Linear Burn.

  12. Save the project.

Edit annotation

Next, you'll edit the annotation features. You'll delete some that aren't useful for your map, and move other ones to new positions.

  1. On the ribbon, click the Edit tab. In the Tools group, click Annotation.

    Annotation button on the Edit tab of the ribbon

  2. On the map, click and drag a box around the Hudson Bay label to select it.

    Selection box around the Hudson Bay label

  3. On the ribbon, in the Features group, click Delete. In the Delete window, click Yes.
  4. Delete the following labels, if they exist:
    • North Pacific Ocean
    • Gulf of Alaska
    • Bering Sea
    • Sea of Okhotsk
    • North Sea
    • North Atlantic Ocean
    • Labrador Sea
  5. Also delete any labels that are farther south than the ones listed above.
  6. Select the 1980 label. Drag it to place it close to the coast of Alaska.

    1980 7.67 million km2 label placed near Alaska.

  7. Move the 2000 label close the middle index line.
  8. Move the 2020 label close to the innermost index line.

    Map with positions of all three index year labels

  9. Select the Greenland Sea label. Drag it off of the pink area so it is easier to read. Keep it within the gray lines.

    Greenland Sea label

  10. Move the other labels as you like. Try to place the labels so they don't overlap with other symbol lines.

    Most of the labels are center-aligned, but one or two may be improved by using a different alignment. You'll change the alignment for one of the labels, and you can repeat the steps for other labels if necessary.

  11. Select The North Western Passages label. On the ribbon, on the Edit tab, in the Selection group, click Attributes.

    Attributes button on the Edit tab of the ribbon

  12. In the lower half of the Attributes pane, click the Left alignment button.

    Left text alignment button

  13. Click Apply. On the map, place The North Western Passages label on the largest nearby island (Victoria Island).

    The North Western Passages label on Victoria Island

  14. On the ribbon, on the Edit tab, in the Selection group, click Clear. In the Manage Edits group, click Save.

    Save and Clear buttons on the Edit tab of the ribbon

  15. In the Save Edits window, click Yes.
  16. Close the Attributes pane and the Modify Features pane.
  17. In the Contents pane, turn off the NorthernMarineRegions layer.
  18. Save the project.

    Map with finished labels

You used an Arcade expression, labeling properties, and annotation editing to create a clearly labeled map.


Arrange a layout

Next, you'll arrange the map, the chart, a legend, and descriptive text into a balanced and informative layout design.

Make a layout

The first items that you'll add to the layout are the map, a title, and guides.

  1. If necessary, reopen Arctic sea ice.aprx in ArcGIS Pro.
  2. On the ribbon, click the Insert tab. In the Project group, click New Layout. Under ANSI – Portrait, click Tabloid (11 by 17 inches or 279 by 432 millimeters).

    Portrait Tabloid layout in the New Layout gallery

  3. Below the Layout view, ensure that Snapping is on.

    Snapping set to On.

  4. On the ribbon, on the Insert tab, in the Map Frames group, click Map Frame. Click either of the options under Map.

    Map Frame button and gallery

  5. Click and drag from one corner of the layout to its opposite corner.

    Your map appears on the layout, filling the whole page. You'll adjust its scale and position later.

    In the Contents pane, a Map Frame was added. It contains the Map and all of the map's layers.

    Map Frame in the Contents pane

    Next, you'll add guides. These won't be visible in your final map, but will help you keep the elements of your layout neatly aligned.

  6. Right-click the ruler surrounding the Layout view and click Add Guides.

    Add Guides

  7. In the Add Guides window, set the following parameters:
    • For Orientation, choose Both.
    • For Placement, choose Offset from edge.
    • For Margin, type 0.5 inches.

    Add Guides window

  8. Click OK.

    Four blue lines appear along the edges of the layout. You should not place any text outside of these margins.

    Next, you'll add a map title. A strong map title helps to communicate the map's message, rather than only describing its data.

  9. On the ribbon, on the Insert tab, in the Graphics and Text group, click Straight text.

    Straight text in the Graphics and Text gallery

  10. Click anywhere on the layout and type ARCTIC SEA ICE DECLINE. Click elsewhere on the page to finish typing.
  11. With the text selected, on the ribbon, click the Text tab. In the Text Symbol group, click Gold. Change the Text Symbol Font Style to Light.

    Text Symbol properties for the title

  12. Drag the corners of the text's bounding box to make it larger. Stretch the text until it touches both side guides. Move it until it also touches the top guide.

    Title positioned between the top three guides.

  13. In the Contents pane, rename the Text element as Title.

    Title in the Contents pane

    Next, you'll position the map under the title.

  14. Below the Layout view, in the scale box, type 22,000,000 and press Enter.

    Scale set to 1:22,000,000.

  15. Right-click the map and click Activate.
  16. Pan the map to reposition it. Place it so the topmost pink spots are immediately below the title, and the Arctic circle is centered between the two side guides.

    Layout with positioned map and title

    Tip:

    To pan and zoom on the layout instead of the map, press and hold the 1 key. If you accidentally zoom on the map, retype 22,000,000 in the scale box. You can also press and hold the right button of the mouse and drag to control the scale.

  17. Above the Layout view, click the Back to Layout link.

    Back to Layout link

    You'll lock the map frame so you don't accidentally move it while you work on other layout elements.

  18. In the Contents pane, next to Map Frame, click the lock button.

    Lock button for Map Frame in the Contents pane

Add a legend

The map needs a legend to explain the meaning of the white, orange, and pink colors. You'll add one to the layout, then convert it to graphics so you can have more control over its appearance.

  1. On the ribbon, on the Insert tab, in the Map Surrounds group, click the lower part of the Legend button and click Legend 1.

    Legend 1 in the Legend gallery

  2. On the map, click and drag to add a legend to the right (south) of the Laptev Sea label.

    Default legend on the map

    The legend describes every layer on the map. This isn't necessary; most layers are background information and don’t need to be explained. You'll remove everything except the color ramp that explains the thematic data.

  3. In the Contents pane, expand Legend. Uncheck all layers except IceExtent_Raster.

    Legend with only one remaining layer

    The legend has a lot of text, but none of it explains what the colors on the map mean. You'll remove some of this text and edit the rest to make a meaningful legend.

  4. If necessary, right-click Legend and click Properties to open the Element pane.
  5. If necessary, click the Options tab.

    Options tab

  6. Under Legend, for Title, uncheck the Show box. Under Legend Items, click Show properties.

    Unchecked Show box and Show properties button

  7. Under Show, uncheck Headings.

    You'll also make the legend patch taller so more of the color variation can be read.

  8. Under Sizing, change Patch height to 30 pt.

    Unchecked Headings box and Patch height set to 30 pt.

    For the legend, you'll use the same font as the rest of the map.

  9. On the ribbon, click the Legend tab. In the Text Symbol group, click Gold.

    You could continue to adjust legend properties, but sometimes it is easier to convert a legend to graphics and edit the pieces directly.

  10. In the Contents pane, right-click Legend and click Convert To Graphics.
  11. In the Contents pane, right-click Legend and click Ungroup.

    Ungroup option in the Legend context menu

    The Legend group breaks up into four graphic layers: three pieces of text and one rectangle.

  12. On the layout, zoom to the legend. Double-click IceExtent_Raster and type Number of Septembers covered in ice from 1979-2021. Click outside of the text box to finish typing.
  13. With the text selected, on the ribbon, ensure that the font size is 10 pt.
  14. Position the text next to the color ramp, between the number labels. Drag the corners of the text box to make it tall and narrow, with only four or five short lines of text.

    Legend title placed next to the color ramp rectangle.

    This text explains what the numbers 1 and 43 (and the colors white and pink) signify. While precise, this explanation is long and not very intuitive. If you were to explain the map to someone out loud, you might tell them that the white areas have always been ice-covered, while the pink areas are only rarely ice-covered. You'll add some text to the legend to include this more conversational explanation as well as the accurate one.

  15. Double-click 43 and type 43 – Always ice-covered. Change the font size to 8 pt.
    Note:

    The number 43 refers to the number of Septembers since 1979. After September 2022, this number should read 44.

  16. Double-click 1 and type 1 – Rarely ice-covered. Change the font size to 8 pt.
  17. If necessary, resize the color ramp and reposition the text.
  18. Drag a box over all of the legend elements to select them. Right-click any of the selected elements and click Group.

    Group option in the legend items' context menu

  19. In the Contents pane, rename Group Element to Legend.

    As the cartographer, it's your responsibility to ensure the symbols on your map are explained clearly. You made the legend easier to understand by removing unnecessary information and rewording the descriptions.

    Layout with map, title, and legend

Fade the edges of the map

The shape of Europe in the lower half of the layout is somewhat distracting. You'll add a subtle fade effect to the map so Europe is less noticeable. Previously, you made a background layer that covers almost the entire earth. You'll reuse this layer to create the fade effect.

  1. In the Contents pane, if necessary, expand Map Frame and expand Map. Right-click Ocean and click Copy.
  2. Right-click Map and click Paste. Rename the new layer Fade.

    Fade layer in the Contents pane

    The map is now hidden behind the new Fade layer and only the title and legend are visible on the layout.

  3. Click the symbol under Fade to open the Symbology pane. If necessary, open the Properties tab. Click the Layers tab.

    Properties and Layers tabs in the Symbology pane

    Symbols in ArcGIS Pro are often made of several symbol layers. This symbol has a Solid stroke symbol layer for the outline, which won't be visible on your map, and a Solid fill symbol layer, which is set to a single beige color.

  4. Click the Solid fill symbol layer and change it to Gradient fill.

    Gradient fill

    You'll adjust the Gradient fill properties so the opaque beige color fades to a fully transparent white near its center (the north pole).

  5. Under Appearance, change second color (white) to No color.
  6. Expand Pattern. Change the following settings:
    • For Direction, choose Circular.
    • For Type, choose Continuous.
    • For Size, type 50 percent.

    Gradient fill properties

  7. Click Apply.

    The map reappears.

    Layout with beige mist

    The fade effect is too gradual: the only fully transparent area doesn't extend far beyond the north pole, so the map's thematic data is partially hidden behind a thin haze. You'll tighten the fade effect so it covers Europe more and the Arctic region not at all.

  8. Under Appearance, click the gradient menu and click Color scheme properties.

    Color scheme properties

  9. In the Color Scheme Editor window, click the beige color stop and change Position to 30 percent.

    The beige color stop is duplicated.

  10. Click the transparent color stop and change Position to 70 percent.

    First transparent color stop with Position set to 70 percent

  11. Click OK. In the Symbology pane, click Apply.

    Europe is now fully faded at the bottom of the layout and the Arctic region is no longer obscured.

    Map with beige gradient

Style a chart

Earlier, you made a chart to help you understand the data. Now, you'll reuse that chart in the layout so you can share that understanding with your map readers. The chart will help to illustrate the change over time better than the map can alone.

  1. On the ribbon, click the Insert tab. In the Map Surrounds group, click the lower part of the Chart Frame button and click the chart under IceExtent.

    Chart Frame gallery with IceExtent chart selected

  2. Click and drag anywhere on the layout to add the chart frame.

    An empty chart frame appears on the map. The chart isn't visible yet because its layer isn't turned on.

  3. In the Contents pane, under Map, turn on the IceExtent layer.

    IceExtent layer turned on in the Contents pane.

    The chart appears on the map. You'll change its appearance to better match the rest of the map.

  4. In the Contents pane, under the IceExtent layer, right-click the chart and click Open.

    The Chart view and Chart Properties pane appear. The first thing you'll change is to remove the legend from the side of the map. There's only one line shown, so a legend isn't necessary.

  5. In the Chart Properties pane, for Split by, choose the blank row at the top of the list.

    Next, you'll change the color of the line.

  6. Click the Series tab. In the table, click the symbol. Under Favorites, click the pink Melt color.

    Melt color in the Favorites list

    Next, you'll remove the commas from the year labels along the x-axis.

  7. Click the Axes tab. Under X-axis, for Number format, click the edit button.

    Edit button for X-axis Number format

  8. For Category, choose Numeric. Click Apply.

    The chart is a bit misleading because the bottom represents the current lowest value, instead of the lowest possible value: zero. You'll change the chart's bounds.

  9. Under Y-axis, change Minimum to 0 and Maximum to 8.

    Y-axis bounds set to 0 and 8.

    There's now room on the chart to add a guide.

  10. Click the Guides tab and click the Horizontal Guide tab. Click Add guide.

    Horizontal Guide and Add guide buttons

  11. For Value, in the first box, type 1. Click the Line Color symbol and choose Tecate Dust. For Dash types, choose Dot.
  12. For Label, type 1 million km2 or less means an ice-free Arctic Ocean.

    Guide properties

    The last ice to melt will be in bays and inlets. This means that the Arctic Ocean will be ice-free long before all of the ice has melted.

    You'll ensure that the chart uses the same font as the rest of the map.

  13. Click the Format tab and click the Text elements tab.

    Text elements tab

  14. Click All Text. For Font, choose Corbel. For Color, under Favorites, choose the gold Text color.
  15. Click Guide Labels. Change Font Size to 10 pt.

    Guide Labels set to 10 pt.

    You'll remove the white background of the chart so it fits more naturally into the rest of the layout design.

  16. Click the Symbol elements tab. Click Background. For Color, choose No color.

    Background Color set to No color.

  17. For Grid Lines, choose Tecate Dust. For X-Axis Line, choose Tecate Dust.

    To finish the chart, you'll simplify the text.

  18. Click the General tab. Change the following titles:
    • For Chart title, type September ice extent.
    • Uncheck X axis title.
    • For Y-axis title, type Million km2.

    Finished chart on the layout

  19. Close the Chart view and the Chart Properties pane.

Add descriptive text

Your map tells an important story, but it is difficult to tell a story with data alone. You'll add descriptive text to the layout to help illuminate the patterns shown in the map and chart, and explain why they matter.

  1. On the ribbon, on the Insert tab, in the Graphics and Text group, click Rectangle text.

    Rectangle text in the Graphics and Text gallery

  2. Click and drag anywhere on the layout to add a text box. Type or copy and paste the following text:

    Systematic measurements of sea ice have been collected via satellite since 1978. Since then, ice packs in both the Arctic and Antarctic have seen consistent decline. This map shows Arctic sea ice extent in the month of September between years 1979 and 2021.

  3. Click outside of the text box to finish typing.
  4. With the text selected, on the ribbon, click the Text tab. In the Text Symbol group, click Gold.
  5. Change the Text Symbol Font Style to Regular.
  6. Position the text box below the title text. Snap the text box to the left guide, below the word Arctic.
  7. Resize the box so the text does not cross the Arctic circle.

    Text box beneath the title

    You'll add another text box to explain the term extent.

  8. Right-click the text and click Copy. Right-click elsewhere on the layout and click Paste.
  9. Drag the new text box to the other side of the layout and position it below the word Decline, snapping it to the right guide.
  10. Delete the existing text and replace it with the following:

    Sea ice extent can be defined as the area covered by at least 15 percent sea ice cover. This measurement is used because with satellite imagery it is often difficult to distinguish between open water and melted water on top of ice.

  11. On the ribbon, on the Format tab, in the Text Symbol group, click the Right horizontal alignment button.

    Text box with right horizontal alignment

  12. If necessary, resize the text box so all text is visible and no text crosses the Arctic circle.

    You'll add more text about the causes and effects of declining sea ice.

  13. Copy one of the text boxes and paste four copies of it onto the layout. Drag the four new text boxes to the bottom of the layout.

    Four text boxes placed near the bottom of the layout.

  14. Edit one of the text boxes to the following:

    The decline in sea ice is caused by global warming. It also contributes to global warming: ice reflects 60-80 percent of radiation from the sun, compared to only 10 percent reflected by open water. When solar radiation is not reflected, it warms the oceans faster.

    As the ice melts, more of the Arctic Ocean becomes open sea, which generates waves. Wave action contributes to further decline of the remaining ice.

    Include the empty line between the paragraphs.

  15. Edit the other three text boxes to the following:
    • September is the month with the least ice cover. Sea ice must persist through September if it is to become or remain multi-year ice, which is thicker and less likely to melt than first-year ice. A lesser September extent means younger ice and faster melting for future years.

    • At some point during this century summer ice will disappear entirely from the Arctic. The most common definition of "ice-free" is a September arctic ice extent of fewer than 1 million square kilometers. At that point, the Arctic Ocean will be open water, although ice will still cling to some coastlines of Canada, Greenland, and Alaska.

    • Ice data: Fetterer, F., K. Knowles, W. N. Meier, M. Savoie, and A. K. Windnagel. 2017, updated daily. Sea Ice Index, Version 3. [Ice extent]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: https://doi.org/10.7265/N5K072F8. [October 2021].

      Other map data: Esri; Garmin International, Inc.; U.S. Central Intelligence Agency; National Geographic Society, Natural Earth

    The last text box contains the credit information. It's important to explain where the map's data came from. However, it doesn't need to be as visually prominent as the other text, so you'll change its text style.

  16. Select the Ice data: Fetterer… text. On the ribbon, change the font style to Light. Change the size to 8 pt.

    Text Symbol properties set to 8 pt and Light.

  17. Drag a box around all four text boxes in the lower part of the layout to select them. On the ribbon, click the Justify horizontal alignment button.

    Justify horizontal alignment button

    You'll resize and position these text boxes later, after you've added the last layout element: an inset map.

    Layout with map, title, legend, chart, and descriptive text

  18. Save the project.

Your layout now consists of a map, a legend, a chart, and some descriptive text, which all work together to tell the story of declining sea ice.


Add an inset map

Sometimes a full story can't be told with only one map, and an inset map, showing a different view of the data, can help. For this layout, you'll create an inset map to highlight the smallest ice extent on record, from September 2012.

Make a new map

To build an inset map, you'll make a copy of your existing map and remove most of the data.

  1. If necessary, reopen Arctic sea ice.aprx in ArcGIS Pro.
  2. Open the Catalog pane. On the Project tab, expand Maps.
  3. Right-click Map and click Copy.

    Copy option in the Map context menu

  4. Right-click Maps and click Paste. Right-click Map1 and click Open.

    Open option in the Map1 context menu

    The new map appears.

  5. In the Contents pane, remove all layers except Index years and ArcticCircle.
  6. Click Index years to select the layer. On the ribbon, click the Feature Layer tab. In the Effects group, change Layer Blend to Normal.

    You'll make two copies of this layer: one to represent all years, and one to represent the year with the smallest ice extent.

  7. In the Contents pane, right click Index years and click Copy. Right-click Map1 and click Paste.
  8. Rename the top Index years layer to 2012.

    2012 layer in the Contents pane

    The map only shows outlines for three years of data. You'll edit the definition query of the bottom layer to show all Septembers.

  9. In the Contents pane, right-click Index years and click Properties. If necessary, click the Definition Query tab.
  10. For Query 1, click Edit.

    The current query filters the data to Septembers and specific years. You'll remove the clause related to years.

  11. On the second query clause, click the Remove clause button.

    Remove clause button next to second clause

  12. Click Apply and click OK.

    The map shows a gold outline for every year of data.

    Map with Arctic Circle and gold ice extent lines

    The map looks interesting but is not very narrative. You'll symbolize the 2012 layer to highlight a specific year.

  13. Right-click 2012 and click Properties. On the Definition Query tab, for Query 1, click Edit.
  14. In the second clause, in the last menu, delete the existing text and type 2012.

    Query 1 edited to September 2012.

  15. Click Apply and click OK.

    The change is not visible on the map because both layers are symbolized in the same way.

  16. Click the symbol for the 2012 layer to open the Symbology pane.
  17. If necessary, click the Properties tab and the Symbol tab.
  18. Change Color to Arctic White. Change Outline color to Cabernet.

    Cabernet in the color menu

  19. Change Outline width to 1 pt.

    Outline width set to 1 pt.

  20. Click Apply.

    Map with white polygon on top of gold lines

    The white fill of the 2012 layer isn't visible against the white background of the Map view, but when you place this map on the layout, it will be visible.

Arrange the inset map and text on the layout

Next, you'll place the inset map on the layout and determine its position and scale.

  1. Above the Map view, click the Layout tab.

    Layout tab above the map view

  2. On the ribbon, click the Insert tab. In the Map Frames group, click Map Frames and click either option under Map1.
  3. Click one of the lower corners of the layout and drag to draw a box that fills the lower half of the layout.

    Inset map added to layout.

  4. Beneath the Layout view, in the scale box, type 40,000,000 and press Enter.

    The map's scale changes.

  5. Right-click the map frame and click Activate. Drag the map so it overlaps the Arctic circle of the larger map in the region of northern Norway. Also overlap the right guide slightly.

    Inset map positioned below the main map.

  6. Click the Back to Layout link.

    The inset map provides some visual balance to the layout. The white area representing the ice extent in 2012 is now visible against the beige background. The Arctic circle helps by providing a visual reference guide with the larger map.

  7. In the Contents pane, rename Map Frame 1 to Inset map. Lock Inset map.

    Inset map in the Contents pane

    The black border surrounding the map frame is distracting, so you'll remove it.

  8. In the Contents pane, click Inset map. On the ribbon, click the Format tab.
  9. In the Current Selection group, click Map Frame and choose Border.

    Border in the Current Selection menu

  10. In the Border group, change Stroke to 0 pt.

    Border Width set to 0 pt.

    The black border surrounding the inset map disappears, allowing the map to sit more naturally on the page. You'll also remove the border from the larger map frame.

  11. In the Contents pane, select Map Frame and remove its border as well.

    Next, you'll rearrange the layout's remaining elements.

  12. Select the The decline in sea ice… text box and place it just below Iceland. Snap it to the left guide and extend it to the right until it almost reaches the inset map.

    Text box positioned and sized on the layout.

  13. With the The decline in sea ice… text box still selected, hold the Shift key and also select the chart and the September is the month… text box. Right-click any of the selected elements, point to Distribute and click Make Same Width.

    Make Same Width in the Distribute menu

  14. Right-click again, point to Align and click Align Left.

    All three elements are now the same width and snapped to the left guide.

  15. Resize the three elements vertically so all text is visible. If necessary, reposition them so the chart lies in the middle.

    Text boxes and line chart

  16. Move the two remaining text boxes so they both are snapped to the right guide. Place the credit text box (Ice data: Fetterer…) on the bottom.

    Text boxes snapped to the right guide.

  17. Select both text boxes and expand them to the left until they are as wide as the inset map.
  18. Resize the two text boxes vertically until all of the text is visible and fits below the inset map.

    Layout with inset map, chart, and text boxes

Add text and transparency to the inset map

Like the larger map, the symbols on the inset map need to be explained. Usually, symbols are explained with a legend, but sometimes they can be explained more simply with labels and other text.

You'll add some explanatory text to the inset map and some transparency to one of its layers.

  1. On the ribbon, on the Insert tab, in the Graphics and Text group, click Rectangle text.

    Rectangle text in the Graphics and Text gallery

  2. Draw two text boxes on top of the inset map. Type or copy and paste the following text into each of them:
    • White areas show the 3.57 million km2 extent of ice in 2012: the smallest Arctic sea ice extent on record.
    • The gold lines show each September ice extent between 1979 and 2021.
  3. Select both text boxes. On the ribbon, click the Text tab. In the Text Symbol group, click Gold.
  4. Change the Text Symbol Font Size to 8 pt. Click the Center horizontal alignment button.

    Text Symbol properties

  5. Place the text describing the white areas over the white center of the inset map.
  6. Place the text describing the gold lines within the Arctic circle, to the east of Greenland.

    Inset map with two text boxes

    The inset map is now fully explained with descriptive text and grouped text that acts like a legend. You'll make one more change to this map: the gold lines overlap one another a lot and it would look more interesting if that overlap was more visible. You'll make each line semitransparent to achieve this effect.

  7. In the Contents pane, expand Inset map. Click the symbol under Index years to open the Symbology pane.

    Symbol for the Index years layer

  8. In the Symbology pane, if necessary, click the Properties tab and the Symbol tab.
  9. For Outline color, from Favorites, choose the gold Text color.

    Outline color set to Text.

    Darker colors are more effective than pale ones when combined with transparency.

  10. Click the Outline color menu again and click Color Properties.
  11. In the Color Editor window, change Transparency to 70 percent.

    Transparency set to 70 percent.

  12. Click OK. In the Symbology pane, click Apply.

    Inset map with transparent lines

    The effect is subtle, but it adds some depth to the tangle of lines and helps to show where the edge of the ice most commonly lies.

Apply finishing touches to the map

Your map is almost complete. You'll add two more finishing touches to improve its polished and professional appearance: you'll add halos to the legend and add a gradient effect to the title.

  1. On the layout, zoom to the legend.

    The legend crosses the Arctic circle, and this dotted line makes the text harder to read. You'll add a halo to mask the Arctic circle where it crosses the text. You'll also apply a gradient effect to the map's title to make it appear bolder.

  2. In the Contents pane, expand the Legend group. Hold the Ctrl key and click all three text elements inside the Legend group.

    Legend text elements selected in the Contents pane.

  3. If necessary, right-click any of the selected elements and click Properties to open the Element pane.
  4. In the Element pane, click the Text Symbol tab.

    Text Symbol tab in the Format Text pane

  5. Expand Halo. For Halo symbol, choose the White fill option.
  6. For Color, under Favorites, choose Land. Change Halo size to 3 pt.

    Halo properties

  7. Click Apply. Click outside of the layout to deselect the text elements.

    The Arctic circle is now masked by the text's halo.

    Legend with halo masking Arctic circle

    Next, you'll add a second color to the title.

  8. On the layout, click the title to select it.

    The Element pane updates to show properties for the Title text element.

  9. In the Element pane, click the Text Symbol tab. Expand Appearance.

    You'll make the title text fade from one color to another.

  10. Click the Text fill symbol menu and click the Linear gradient fill option.

    Linear gradient fill option in the Text fill symbol menu

  11. For Colors, click the first color (gray) and from Favorites, choose Melt.
  12. Click the second color (white) and click Eyedropper.

    Eyedropper button in the color menu

  13. Point to the map until you find a medium orange color. Click to select this color.

    Eyedropper tool and orange color on map

  14. In the Symbology pane, click Apply.

    The title is now bolder in appearance because of its bright colors. It also imitates the map's symbology and appears to be melting.

    Title with pink and orange gradient

    The map is almost complete.

  15. Reposition any elements of the layout that you aren't pleased with.
  16. Right-click the ruler bordering the Layout view and uncheck Guides to preview the layout without guides.

    Final layout design

  17. Save the project.

Export the layout

Your map is ready to export. You'll export it as a .png file, which you can later print or share online.

  1. On the ribbon, click the Share tab. In the Output group, click Export Layout.

    Export Layout button on the Share tab of the ribbon

  2. In the Export pane, for File Type, choose PNG.
  3. For Name, click the Browse button. Choose a location you can easily access and name the file ArcticSeaIceDecline.png. Click Save.
  4. Ensure that the remaining parameters match the following:
    • Uncheck Clip to graphics extent.
    • Leave Transparent background unchecked.
    • For Resolution, confirm that it is set to 300 DPI.
    • For Color depth, confirm 32-bit with Alpha is selected.

    Export Layout settings

  5. Click Export.
  6. Click View exported file to open the .png file.

    View exported file link

Your map is complete. You explored a large dataset and filtered it down to a smaller subset. You chose an appropriate projected coordinate system and designed symbols, labels, a legend, and a chart. You arranged all of these elements together in a well-balanced and informative layout.

Arctic sea ice continues to decline, and this map helps to illustrate where and when the decline has occurred so far. The dataset in its raw form was unable to tell this story clearly, but your many cartographic decisions brought the data to life and made it easy to understand.

Map design is a creative task. You are encouraged to find other ways to arrange, symbolize, and present this dataset. The following are some suggestions for how to make this map your own design:

  • Rearrange the map and other elements for a landscape page (wider than it is tall).
  • Chart the change in ice extents with a data clock.
  • Create a map that compares September ice extents to February ice extents.
  • Use a blue color scheme.

Consider this example of a map that goes further than the instructions presented here.

You can find more cartography lessons on the How to make a map page.