Reveal lake shrinkage due to severe drought

Severe droughts and higher temperatures due to climate change are of increasing concern around the world. As regional and global temperatures are significantly increasing, the water levels are dropping in many major water bodies that people, plants, and animals depend on. One way you can raise awareness of this important issue is by visualizing how much lakes are shrinking using imagery and GIS.

Drought is not the only cause of lake shrinkage. Many lake levels rise and fall due to regular seasonal variation. Some may be drained for maintenance or irrigation purposes or dammed for other human development purposes. However, the lakes that you will explore in this tutorial have severe drought as a significant contributing factor for their falling water levels.

In this tutorial, you will access imagery layers using the World Imagery Wayback app, configure a web map with bookmarks to several major lakes that are shrinking due to severe drought, and create a story with interactive swipe maps to compare the before and after imagery of the lakes.

This tutorial was last tested on December 15, 2023.

View final result

Requirements

• ArcGIS account (see options for software access)

Reveal lake shrinkage due to severe drought

Add imagery layers to a map

Map-based apps provide a simplified interface that allows you to share a story or message in a focused way and allows others to explore the map with a specific purpose in mind. The World Imagery Wayback app is a digital archive, providing users with access to the different versions of the World Imagery layer as they existed on the date they were published. Each layer is a high-resolution imagery snapshot of the entire world built from satellite and aerial imagery available at the time.

You will use the World Imagery Wayback app to identify two world imagery layers and add them to a map. First you will get familiar with the app.

1. Go to the World Imagery Wayback app.

   The World Imagery Wayback app appears. It includes a side toolbar, a pane with a timeline and list of layers for each date of the imagery, and a map.

   

   Next, you will navigate to a major lake in the United States that has significantly reduced in size due to severe drought.

2. In the search bar, type Great Salt Lake and press Enter.

   

   The map zooms to the Great Salt Lake in Utah.

   It is the largest saltwater lake in the Western Hemisphere and supports life that thrives in water that is much saltier than seawater, such as brine shrimp and flies that millions of birds rely on for food. As the lake water levels go down, the food source for birds is in danger. Another negative effect is that the exposed, dry lake bed has increased the amount of dust going into the air. The dust contains copper, arsenic, and other heavy metals that may pose a public health threat to the human populations living nearby as they can worsen respiratory diseases.

   

   You can see the date the imagery was published below the timeline.

   

   Note:

   The Wayback app map opens with the most recent World Imagery layer, so the date you see will not match the one in the graphic.

3. In the side pane, remove the check for Only versions with local changes.

   

4. In the side pane, scroll down and point to the 2019-05-15 layer.

   

   A preview window appears.

   
5. In the side pane, click the 2019-05-15 layer.

   

   The map displays imagery from May 2019. The lake is much fuller compared to the initial image you saw.

   

   Note:

   For this tutorial, you are only comparing imagery of the lakes in 2019 and a later year. The Great Salt Lake has been declining in size since the 1980s. On your own, consider exploring earlier years of imagery of the lakes in this tutorial.

6. Click the Add this release to an ArcGIS Online Map button.

   

   On the toolbar, the imagery layer is added to the queue and the Open these versions in a new Map Viewer button updates to show how many layers you have in the queue.

   

   Next, you will add the latest imagery from the same month.

   The water level of a lake often changes based on the season. Each year, in the warmer months, there is less water in the lake, due to heightened evaporation rates and less precipitation (such as rain). In the colder months, there is more water in the lake due to lower evaporation rates, more frequent precipitation, and snow melt flowing in. You want to visualize water loss that happens over years, not seasonally. For that reason, you will choose images in the same month (May) for different years.

   Note:

   The 2022-05-18 layer, from May 2022, is used in the following sections’ graphics. You are encouraged to use the latest layer from May available, but may select the May 2022 layer if you wish.
7. Scroll to and click the latest year’s May layer. Alternatively, click the 2022-05-18 layer, from May 2022.  Click the Add this release to an ArcGIS Online Map button for the May layer you want to use in your map.

   

   You now have two layers selected in the Wayback app.

8. On the toolbar, click the Open these versions in a new Map button.

   

   The ArcGIS Online sign in page appears.

9. Sign in to your ArcGIS account.

   Note:

   If you don't have an ArcGIS account, see options for software access.

10. In the Wayback Map Settings window, provide the following:
    • For Title, type Lakes shrinking due to severe droughts.
    • For Tags, add drought and climate change.
    • For Description, type Imagery from Wayback app for May 2019 and May [insert the year of the layer you selected] revealing lake shrinkage due to droughts.

    

11. Click Create Wayback Map.

    A message states that the map is ready.

12. Click Open Wayback Map.

    The item page for your map appears.

13. On the item page, click Open in Map Viewer.

    

    The map opens in Map Viewer with the Layers pane open.

    

    The Layers pane contains two group layers and two layers. The group layers are metadata layers for the imagery layers. World Imagery (Wayback 2019-05-15) and the other layer are the layers you chose in the Wayback app.

    Note:

    The metadata layers contain information for the imagery layer at different resolutions, such as the data provider, collection date, resolution, accuracy, and source of the imagery. See Learning more about the World Imagery basemap to learn more about the metadata layers.

    Your map currently shows the later year's imagery layer because the 2019 layer is turned off.

14. In the Layers pane, click the visibility button for the 2019 layer on and off to switch between the 2019 and the later year's imagery layers.

    

    By turning the 2019 layer on and off, you can compare the imagery of the newer layer and the 2019 layer.

You have added imagery layers to your map using the World Imagery Wayback app.

Create bookmarks to lakes

Next, you will prepare the map so you can share a story about lakes shrinking due to severe drought. While you used the Great Salt Lake location to determine which imagery layers to choose for your map, the Wayback imagery layers show images for the whole world. You will create bookmarks to quickly navigate to different lakes that have also been impacted by drought.

1. On the Contents (dark) toolbar, click Bookmarks. In the Bookmarks pane, click Add bookmark.

   

2. For Title, type Great Salt Lake and click Add.

   A bookmark for the Great Salt Lake is created. Next, you will create bookmarks for a few other major lakes shrinking due to drought around the world.

3. On the map, click Search.

   

   A search bar appears at the top of the map.

4. In the search bar, type Lago Poopó and press Enter.

   The map zooms to Lake Poopó in Bolivia.

   Lake Poopó is located in the Bolivian Altiplano Mountains (more than 12,000 feet above sea level) and is only about 10 feet deep on average. Because of these characteristics, it has a high evaporation rate. Since the 1990s, with increased temperatures due to climate change, the evaporation rate for the lake tripled.

   

5. Close the Search result pop-up and drag the map so the lake is centered.
6. In the Layers pane, turn the 2019 layer on and off to compare the lake shrinkage between the later year and 2019.

   Lake Poopó had a much higher water level in 2019.

   

   Drought and climate change have resulted in the many glaciers of South America shrinking, which in turn has been an additional driving factor for the lake losing water. The lack of water in the lake has impacted the region’s ecology and the people who relied on fishing in the lake for their livelihood.

7. Use what you have learned to create a bookmark for Lake Poopó.

   Tip:

   On the Contents toolbar, click Bookmarks. In the Bookmarks pane, click Add bookmark. Name the new bookmark and click Add.

   Next, you will add a third bookmark for your map.

8. Use what you have learned to navigate to Lake Urmia in Iran and create a bookmark.

   Lake Urmia is located in Iran and is an important contributor to the local economy through tourism. Its marshes support over 200 species of birds and other species who rely on the lake to survive. The lake has receded to ten percent of its original size due to dammed rivers, increased groundwater pumping, diversions, climate change, and drought.

   You now have three bookmarks to lakes that have been shrinking due to droughts.

   

   Note:

   Optionally, you can add more bookmarks to more lakes. Consider exploring Lake Mead (Nevada and Arizona, United States), Lake Faguibine (Mali), Lake Puzhal (India), Hamun Lake (Iraq), and Lake Chad (west-central Africa).

   Next, you will save the map and create a story using ArcGIS StoryMaps.

9. On the Contents toolbar, click the Save and open button and click Save.

   

Create a story

Sharing a story using ArcGIS StoryMaps is an effective way to communicate information through maps in an interactive and compelling way. You will create a story containing a swipe map, which will allow your readers to swipe and compare the imagery layer in 2019 and the later year's layer for each of the lakes you bookmarked on the map. You will include narrative paragraphs on the impact of each shrinking lake on the local area and provide references for the information.

1. On the Contents toolbar, click the Create app button and choose ArcGIS StoryMaps.

   

   Your map appears in ArcGIS StoryMaps.

2. For the Story title, type Reveal lake shrinkage due to severe drought, and for the short introduction, type Explore several lakes that have been shrinking due to climate change and drought.

   Next, you will add an introductory paragraph.

3. Point to the space above the map and click the Add content block button.

   

4. Choose Text.

   

5. Copy and paste the following paragraph:

   Tip:

   To paste text without formatting, press Ctrl+Shift+V when pasting.

   As regional and global temperatures significantly increase, major water bodies that people, plants, and animals depend on are drying. Severe droughts due to climate change are of increasing concern to water supplies around the world, keeping these lakes from replenishing as they dry or as increasing human populations drain more water from them. Change in lakes is to some extent typical; they rise and fall with regular seasonal variation. Some may be drained for maintenance or irrigation purposes or dammed for other human development purposes. But severe drought, especially one that occurs for many consecutive years, may be one of many cumulative impacts for why lakes are shrinking. The lakes that you will explore in this story are lakes where drought is a significant contributing factor for the falling water levels.

   Next, you will add a heading for the first lake.

6. Add another text content block after the introductory paragraph and type Great Salt Lake.
7. Highlight the text, and in the text editor menu, click Paragraph and choose Heading 1.

   

   The text updates to a Heading 1 style.

   

   Next, you want to add a swipe map. By default, your web map is added to the story as you last saved it. You will delete it and replace it with a swipe map that references your saved web map.

8. Point to the map, and on the menu bar, click the Delete button.

   

9. In the Delete map? window, click Yes, delete.
10. Under the heading text Great Salt Lake, click the Add content block button, and under Media, click Swipe.

    A blank swipe map is added to your story.

11. On the left, click Web map.

    

12. In the Add a web map window, choose the Wayback Imagery Shrinking Lakes map.
13. In the Adjust map appearance window, click the Bookmarks tab, and choose Great Salt Lake.

    

14. Click the Layers tab, and click the Visibility button for the 2019-05-15 layer so it is visible.

    

15. Adjust the map extent and click Place map.

    

16. On the right of the swipe map, click Web map. Choose the Lakes shrinking due to severe droughts map. In the Adjust map appearance window, use what you have learned to configure the map so that the Great Salt Lake later year's imagery layer is visible and click Place Map.
17. On the swipe map menu, click the Large button.

    

18. Under the swipe map, click Add a caption and type or copy and paste the following:

    Imagery of the Great Salt Lake in Utah, USA, May 15, 2019 (left) and [date of the later year's imagery], [year of the later year's imagery] (right).

    

    Your swipe map is complete. To fill out the story, you will add a paragraph with more information about the Great Salt Lake, how drought has contributed to its reduced size, and how it has impacted the local community and ecology.

19. After the swipe map, click the Add content block button and choose Text. Copy and paste the following paragraph:

    The shrinking of the Great Salt Lake in Utah, also known as America's Dead Sea, has significant consequences for the people, ecology, and economy of northern Utah (Marks, 2022). It is the largest salt water lake in the Western Hemisphere and supports life that thrives in water that is much saltier than seawater, such as brine shrimp and flies that millions of birds rely on for food. As the lake water levels go down, not only is the food source for birds in danger, but the exposed, dry lake bed has increased the amount of dust going into the air. The dust contains copper, arsenic, and other heavy metals that may pose a public health threat to nearby populated areas if they are inhaled, which can make respiratory diseases worsen (European Space Agency, 2022).

You have added a heading, swipe map, and contextual paragraph for the Great Salt Lake. Next, you will use what you have learned to do the same for the remaining two lakes in your web map.

Continue building the story

You will use what you have learned to add the remaining two lakes to your story and add reference citations.

1. Use what you have learned to add heading text for Lake Poopó.
2. Use what you have learned to create a swipe map showing Lake Poopó in 2019 on the left and in the later year on the right.
3. Below the swipe map, add the following caption text:

   Imagery of the Lake Poopó, located in Bolivia, on May 15, 2019 (left) and [date of the later year's imagery], [year of the later year's imagery] (right).

4. Below the swipe map, add a Text content block and copy and paste the following paragraph:

   Lake Poopó is located in the Bolivian Altiplano Mountains (more than 12,000 feet above sea level) and is only about 10 feet deep on average. Because of these characteristics, it has a high evaporation rate. Since the 1990s, increased temperatures due to climate change have tripled the evaporation rate for the lake (Rafferty, 2016). Drought and climate change have resulted in many of the glaciers of South America shrinking, which in turn has been the driving factor for the lake losing water (Marks, 2022). The lack of water in the lake has impacted the region’s ecology and economy, threatening the livelihoods of people who relied on fishing in the lake (Rafferty, 2016).

   Next, you will add content for the final lake on your map.

5. Use what you have learned to add heading text for Lake Urmia.
6. Use what you have learned to create a swipe map showing Lake Urmia in 2019 on the left and in the later year on the right.
7. Below the swipe map, add the following caption text:

   Imagery of the Lake Urmia, located in Iran, on May 15, 2019 (left) and [date of the later year's imagery], [year of the later year's imagery] (right).

8. Below the swipe map, add a Text content block and copy and paste the following paragraph:

   Lake Urmia is located in Iran and is an important contributor to the local economy through tourism. Its marshes support over 200 species of birds and other species who rely on the lake to survive. The lake has receded to 10 percent of its original size due to dammed rivers, increased groundwater pumping, diversions, climate change, and drought (Marks, 2022).

   Finally, you will add the citation for the information in the paragraphs.

9. Scroll to the bottom of the story. Click Add a credits heading and type References.

   

10. For Content, type Rafferty, John P. (2016). For Attribution, type 7 Lakes That Are Drying Up https://www.britannica.com/list/7-lakes-that-are-drying-up.

    

11. Click the Add credit button and add the following references:
    • Marks, K. (2022). 25 Worst Drying Lakes in the World. https://owlcation.com/stem/10-Worst-Drying-Lakes-in-the-World.
    • The European Space Agency (2022). Utah’s Great Salt Lake is disappearing https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Utah_s_Great_Salt_Lake_is_disappearing#:~:text=As%20the%20lake%20shrinks%2C%20it,of%20dust%20in%20the%20air.

You have completed adding content to your story. Optionally, you can add more sections and references for more lakes you want to include in the story.

Design and publish the story

Before you publish and share the story, you will add some final design touches to enhance your reader’s experience. First, you’ll turn on Navigation, which allows the reader to quickly jump to any part of the story formatted as a header. Then, you’ll update the theme.

1. On the ribbon of the ArcGIS StoryMaps editor, click Design.

   

2. In the Design pane, under Optional story sections, turn on Navigation.

   The names of the lakes are added to the top of the story. Clicking the name of a lake will jump you to that section of the story to explore.

3. For Theme, choose Obsidian.

   

   The overall story design updates with a black background, white font, and red design accents. The new design conveys a serious tone, which matches with the dire nature of the impacts of shrinking lakes due to climate change and droughts.

   

   The added navigation bar provides links to all the text set to the Heading 1 format, allowing readers to jump to that section of the story.

   Next, you will add a cover image.

4. Close the Design pane.
5. Download the image lake-shrinking.jpg.
6. At the top of your story, click Add cover image or video.

   

7. Drag the image you downloaded to the Add an image or video section, or click Browse your files and choose the lake-shrinking.jpg image. Click Add.

   The cover image is added to your story.

   

   Before you publish, it is important to preview the story and ensure it appears as you intended.

8. On the ribbon, click Preview.

   A message appears indicating that continuing will reset the undo history.

9. Click Yes, continue.

   Your story appears in preview mode.

10. Scroll through your story, checking for typos, testing out the swipe maps, and ensuring your captions and citations are correct. When you are finished, click the Close Preview button.

    

11. On the ribbon, click Publish.

    The Publish options window appears. Your story is ready to share.

12. Under Share, for Set sharing level, choose Everyone (Public) and click Publish.

    

13. In the Share items window, click Yes, share these items.

    Your published story appears. You can now share the URL with anyone to explore and learn more about lakes around the world shrinking due to severe droughts and climate change.

In this tutorial, you used the World Imagery Wayback app to explore and select imagery layers to show the decreasing water level of the Great Salt Lake in Utah. You created a web map from those layers and added bookmarks to navigate to more lakes that have been shrinking due to droughts. You created a story with swipe maps for viewers to explore the extent of lake shrinkage and provided additional information for how the lake shrinkage has impacted each region's local community, economy, and ecology.

GIS is a tool to view and better understand environmental conditions, support mitigating impacts of drought, and use for future planning, managing natural resources, and remediating shrinking lakes. Read the Drought story from Climate Mapping for Resilience and Adaptation to learn more about droughts and funding opportunities for governments and communities to build resilience to drought.

You can find more tutorials in the tutorial gallery.

Acknowledgements

• World Imagery (Wayback 2019-05-15) and World Imagery (Wayback 2022-05-18) sources include Esri, DigitalGlobe, Earthstar Geograpics, CNES/Airbus DS, USDA FSA, USGS, Aerogrid, IGN, IGP, and the GIS User Community.
• Cover image in story by Ross Stone on Unsplash.
• World Imagery layer sources: Esri, Maxar, Earthstar Geographics, and the GIS User Community