{"id":390782,"date":"2019-02-13T04:50:48","date_gmt":"2019-02-13T12:50:48","guid":{"rendered":"http:\/\/www.esri.com\/arcgis-blog\/?post_type=blog&p=390782"},"modified":"2024-11-11T12:35:15","modified_gmt":"2024-11-11T20:35:15","slug":"one-symbol-from-multiple-fields-in-arcade","status":"publish","type":"blog","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade","title":{"rendered":"Earthquake Mapping Part I: One Symbol from Multiple Fields in Arcade"},"author":8492,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":{"_acf_changed":false,"_searchwp_excluded":""},"categories":[777102,23851,22941],"tags":[42641,26131,268131,40161],"industry":[],"product":[36581,36551],"class_list":["post-390782","blog","type-blog","status-publish","format-standard","hentry","category-arcade","category-data-management","category-mapping","tag-arcgis-online","tag-earthquake","tag-living-atlas","tag-living-atlas-of-the-world","product-arcgis-living-atlas","product-arcgis-online"],"acf":{"short_description":"With just a few lines of Arcade code you can take multiple fields within your ArcGIS Online data and combine them into one unified symbol.","flexible_content":[{"acf_fc_layout":"content","content":"

Have you ever had multiple fields in your data that you wanted to display as one unified symbol in ArcGIS Online? Arcade makes it easy to take any fields in your dataset and combine them into one symbol on your map.<\/p>\n

The steps are outlined below using Esri’s Live Feed earthquake data.<\/p>\n

At the end follow the link to Earthquake Mapping Part II: The Cartography of Time, Magnitude, and Alert Levels<\/a> which dives deeper into the cartographic riddle for displaying hundreds of earthquake symbols on a map.<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"image","image":{"ID":428362,"id":428362,"title":"eem_18_earthquakes189","filename":"eem_18_earthquakes189.jpg","filesize":95627,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes189","alt":"A portion of the front page of the first Daily News published on April 18, 1906 after a 7.9 earthquake struck San Francisco, California.","author":"8492","description":"A portion of the front page of the first Daily News published on April 18, 1906 after a 7.9 earthquake struck San Francisco, California.","caption":"","name":"eem_18_earthquakes189","status":"inherit","uploaded_to":390782,"date":"2019-02-02 03:13:30","modified":"2019-02-11 22:14:15","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":681,"height":253,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189-300x111.jpg","medium-width":300,"medium-height":111,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189.jpg","medium_large-width":681,"medium_large-height":253,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189.jpg","large-width":681,"large-height":253,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189.jpg","1536x1536-width":681,"1536x1536-height":253,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189.jpg","2048x2048-width":681,"2048x2048-height":253,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189.jpg","card_image-width":681,"card_image-height":253,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes189.jpg","wide_image-width":681,"wide_image-height":253}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/commons.wikimedia.org\/wiki\/File:SF_Daily_News_April_18_1906.gif"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Earthquake Data in the Living Atlas<\/h2>\n

The Living Atlas of the World<\/a> hosts recent global earthquakes<\/a> from the U.S. Geological Survey (USGS) and their Prompt Assessment of Global Earthquakes for Response (PAGER<\/a>) program.<\/p>\n

This Live Feed is updated every five minutes and has fields detailing individual earthquake information including an event’s ID, Hours Old, Magnitude, Location, and PAGER Alert Level.<\/p>\n"},{"acf_fc_layout":"image","image":{"ID":405882,"id":405882,"title":"eem_18_earthquakes103","filename":"eem_18_earthquakes103.jpg","filesize":29864,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes103","alt":"The first 30 seconds of the 6.9 Richter magnitude Loma Prieta earthquake that struck the Bay Area along the San Andreas Fault in California on October 17, 1989.","author":"8492","description":"","caption":"The first 30 seconds of the 6.9 Richter magnitude Loma Prieta earthquake that struck the Bay Area along the San Andreas Fault in California on October 17, 1989.","name":"eem_18_earthquakes103","status":"inherit","uploaded_to":390782,"date":"2019-01-10 18:02:43","modified":"2019-02-02 03:39:40","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":580,"height":223,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103-300x115.jpg","medium-width":300,"medium-height":115,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103.jpg","medium_large-width":580,"medium_large-height":223,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103.jpg","large-width":580,"large-height":223,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103.jpg","1536x1536-width":580,"1536x1536-height":223,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103.jpg","2048x2048-width":580,"2048x2048-height":223,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103.jpg","card_image-width":580,"card_image-height":223,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes103.jpg","wide_image-width":580,"wide_image-height":223}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes74.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Attributes and Fields<\/h2>\n

All hosted feature layers in ArcGIS Online contain an attribute table<\/a>.\u00a0\u00a0Attribute tables have rows (features) and columns (fields) that store the data for that layer.<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"image","image":{"ID":401332,"id":401332,"title":"eem_18_earthquakes73","filename":"eem_18_earthquakes73.jpg","filesize":125352,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes73","alt":"Image showing earthquake data fields.","author":"8492","description":"","caption":"","name":"eem_18_earthquakes73","status":"inherit","uploaded_to":390782,"date":"2019-01-07 16:56:35","modified":"2019-02-02 03:41:38","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":1715,"height":706,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73-300x123.jpg","medium-width":300,"medium-height":123,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73-768x316.jpg","medium_large-width":768,"medium_large-height":316,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73-1024x422.jpg","large-width":1024,"large-height":422,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73.jpg","1536x1536-width":1536,"1536x1536-height":632,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73.jpg","2048x2048-width":1715,"2048x2048-height":706,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73-826x340.jpg","card_image-width":826,"card_image-height":340,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73.jpg","wide_image-width":1715,"wide_image-height":706}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes73.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

What’s Important for Mapping Earthquakes?<\/h2>\n

This map needs to show earthquakes of interest, but not get obscured by the hundreds of other points that are also part of the story.\u00a0 The map will need to logically show:<\/p>\n

When was the earthquake?
\n<\/em>How big was the earthquake?
\n<\/em>What are the impacts on people and the environment?<\/em><\/p>\n

This is a situation where the important information is contained in three fields of our data:<\/p>\n

Hours Old
\n<\/em>Magnitude
\n<\/em>Alert Level<\/em><\/p>\n

Let’s first take a look at how these fields look individually:<\/p>\n

 <\/p>\n

Classified by Hours Old<\/p>\n"},{"acf_fc_layout":"image","image":{"ID":435902,"id":435902,"title":"eem_18_earthquakes203","filename":"eem_18_earthquakes203.jpg","filesize":183155,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes203","alt":"Earthquake data classified by Time.","author":"8492","description":"","caption":"","name":"eem_18_earthquakes203","status":"inherit","uploaded_to":390782,"date":"2019-02-13 03:44:35","modified":"2019-02-13 03:47:48","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":1477,"height":861,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203-300x175.jpg","medium-width":300,"medium-height":175,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203-768x448.jpg","medium_large-width":768,"medium_large-height":448,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203-1024x597.jpg","large-width":1024,"large-height":597,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203.jpg","1536x1536-width":1477,"1536x1536-height":861,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203.jpg","2048x2048-width":1477,"2048x2048-height":861,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203-798x465.jpg","card_image-width":798,"card_image-height":465,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203.jpg","wide_image-width":1477,"wide_image-height":861}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes203.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Classified by Magnitude<\/p>\n"},{"acf_fc_layout":"image","image":{"ID":436082,"id":436082,"title":"eem_18_earthquakes207","filename":"eem_18_earthquakes207.jpg","filesize":183685,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes207","alt":"Earthquake data classified by Magnitude.","author":"8492","description":"","caption":"","name":"eem_18_earthquakes207","status":"inherit","uploaded_to":390782,"date":"2019-02-13 04:13:08","modified":"2019-02-13 04:13:30","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":1476,"height":860,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207-300x175.jpg","medium-width":300,"medium-height":175,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207-768x447.jpg","medium_large-width":768,"medium_large-height":447,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207-1024x597.jpg","large-width":1024,"large-height":597,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207.jpg","1536x1536-width":1476,"1536x1536-height":860,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207.jpg","2048x2048-width":1476,"2048x2048-height":860,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207-798x465.jpg","card_image-width":798,"card_image-height":465,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207.jpg","wide_image-width":1476,"wide_image-height":860}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes207.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Classified by Alert Level<\/p>\n"},{"acf_fc_layout":"image","image":{"ID":435922,"id":435922,"title":"eem_18_earthquakes205","filename":"eem_18_earthquakes205.jpg","filesize":186721,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes205","alt":"Earthquake data classified by Alert Level.","author":"8492","description":"","caption":"","name":"eem_18_earthquakes205","status":"inherit","uploaded_to":390782,"date":"2019-02-13 03:54:02","modified":"2019-02-13 03:54:21","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":1478,"height":863,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205-300x175.jpg","medium-width":300,"medium-height":175,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205-768x448.jpg","medium_large-width":768,"medium_large-height":448,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205-1024x598.jpg","large-width":1024,"large-height":598,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205.jpg","1536x1536-width":1478,"1536x1536-height":863,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205.jpg","2048x2048-width":1478,"2048x2048-height":863,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205-796x465.jpg","card_image-width":796,"card_image-height":465,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205.jpg","wide_image-width":1478,"wide_image-height":863}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes205.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

It’s hard to differentiate the earthquake’s time, size, and severity as you flip between the maps and yet we need to be able to see them all.<\/p>\n

<\/h2>\n

 <\/p>\n

Interpretation is at the Heart of Our Work<\/h2>\n

Is a 6.5 magnitude earthquake important? It depends right?<\/p>\n

When did it happen? Where? In the middle of nowhere?\u00a0 A populated area?\u00a0 Are roads and buildings damaged or are people hurt?<\/p>\n

We want to display each of our three fields genuinely, but also honor and respect each attribute’s contribution towards\u00a0understanding of the complete dataset.<\/p>\n

Compelling map symbology requires knowing your data fields, evaluating each one’s importance, and being able to interpret them together in a way that will uniquely, and beautifully,\u00a0 tell their story.<\/p>\n

In order to visualize the fields together on one map they need to become combinations of:<\/p>\n

3 Time Periods – Past 24 hours, 1 week, and 3 months
\n<\/em>4 Ranges of Magnitude-\u00a0 4 to 4.9, 5 to 5.9, 6 to 6.9, and +7
\n<\/em>5 Classes for Alert Level – None, Green, Yellow, Orange, and Red<\/em><\/p>\n

Without any additional data processing we will use Arcade to join these fields together to form new sets of information for our map.<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"image","image":{"ID":428342,"id":428342,"title":"eem_18_earthquakes188","filename":"eem_18_earthquakes188.jpg","filesize":204176,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes188","alt":"Damage to apartment building at Beach and Divisadero Streets in the San Francisco Marina District from the 1989 Loma Prieta Earthquake the week of October 17, 1989.","author":"8492","description":"Damage to apartment building at Beach and Divisadero Streets in the San Francisco Marina District from the 1989 Loma Prieta Earthquake the week of October 17, 1989. ","caption":"Damage to apartment building at Beach and Divisadero Streets in the San Francisco Marina District from the 1989 Loma Prieta Earthquake the week of October 17, 1989. ","name":"eem_18_earthquakes188","status":"inherit","uploaded_to":390782,"date":"2019-02-02 03:08:58","modified":"2019-02-02 03:28:13","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":1385,"height":909,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188-300x197.jpg","medium-width":300,"medium-height":197,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188-768x504.jpg","medium_large-width":768,"medium_large-height":504,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188-1024x672.jpg","large-width":1024,"large-height":672,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188.jpg","1536x1536-width":1385,"1536x1536-height":909,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188.jpg","2048x2048-width":1385,"2048x2048-height":909,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188-708x465.jpg","card_image-width":708,"card_image-height":465,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes188.jpg","wide_image-width":1385,"wide_image-height":909}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/commons.wikimedia.org\/wiki\/File:Damage_to_apartment_building_at_Beach_and_Divisadero_Streets_from_the_1989_Loma_Prieta_Earthquake.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Before you Start<\/h2>\n

Esri’s Earthquake data is located here<\/a>\u00a0(copy the URL on the bottom right of the page<\/em>).\u00a0 Add this as a Web Layer to your ArcGIS Online map.<\/p>\n

Begin by filtering out all of the smaller earthquakes that are < 4 magnitude.<\/p>\n"},{"acf_fc_layout":"image","image":{"ID":392932,"id":392932,"title":"eem_18_earthquakes8","filename":"eem_18_earthquakes8.jpg","filesize":32380,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes8","alt":"Demonstration image on \"Apply Filter\".","author":"8492","description":"","caption":"","name":"eem_18_earthquakes8","status":"inherit","uploaded_to":390782,"date":"2018-12-28 03:34:48","modified":"2019-02-02 03:43:03","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":640,"height":273,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8-300x128.jpg","medium-width":300,"medium-height":128,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg","medium_large-width":640,"medium_large-height":273,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg","large-width":640,"large-height":273,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg","1536x1536-width":640,"1536x1536-height":273,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg","2048x2048-width":640,"2048x2048-height":273,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg","card_image-width":640,"card_image-height":273,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg","wide_image-width":640,"wide_image-height":273}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes8.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Since earthquakes that are within the range of 4-4.9 magnitude (See\u00a0The Modified Mercalli Intensity Scale)<\/a>\u00a0are detectable by people outdoors and are strong enough to wake some people up at night, this is a good threshold for representation on the map.\u00a0 See this blog<\/a> about applying filters.<\/em><\/p>\n

 <\/p>\n

Building the Expression<\/h2>\n

Click to “Change Style” of the layer.<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"image","image":{"ID":405722,"id":405722,"title":"eem_18_earthquakes99","filename":"eem_18_earthquakes99.jpg","filesize":23614,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes99","alt":"Demonstration image showing how to make \"Change Style\".","author":"8492","description":"","caption":"","name":"eem_18_earthquakes99","status":"inherit","uploaded_to":390782,"date":"2019-01-10 17:43:40","modified":"2019-02-02 03:40:15","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":427,"height":224,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99-300x157.jpg","medium-width":300,"medium-height":157,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg","medium_large-width":427,"medium_large-height":224,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg","large-width":427,"large-height":224,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg","1536x1536-width":427,"1536x1536-height":224,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg","2048x2048-width":427,"2048x2048-height":224,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg","card_image-width":427,"card_image-height":224,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg","wide_image-width":427,"wide_image-height":224}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes99.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Under “Choose an attribute to show” scroll to the bottom and select “New Expression”.<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"image","image":{"ID":405732,"id":405732,"title":"eem_18_earthquakes98","filename":"eem_18_earthquakes98.jpg","filesize":34843,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes98","alt":"Demonstration image showing how to make a \"New Expression\".","author":"8492","description":"","caption":"","name":"eem_18_earthquakes98","status":"inherit","uploaded_to":390782,"date":"2019-01-10 17:44:11","modified":"2019-02-02 03:40:01","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":426,"height":440,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98-290x300.jpg","medium-width":252,"medium-height":261,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg","medium_large-width":426,"medium_large-height":440,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg","large-width":426,"large-height":440,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg","1536x1536-width":426,"1536x1536-height":440,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg","2048x2048-width":426,"2048x2048-height":440,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg","card_image-width":426,"card_image-height":440,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg","wide_image-width":426,"wide_image-height":440}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes98.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Paste in the following Arcade expression:<\/p>\n

var MAG=When(
\n$feature.mag >= 4 && $feature.mag < 5, “Mag 4-4.9”,
\n$feature.mag >= 5 && $feature.mag < 6, “Mag 5-5.9”,
\n$feature.mag >= 6 && $feature.mag < 7, “Mag 6-6.9”,
\n“Mag >= 7”)<\/p>\n

var TIME=When(
\n$feature.hoursOld < 25, “Past 24 Hr”,
\n$feature.hoursOld > 24 && $feature.hoursOld < 145, “Past Week”,
\n“Past 3 Months”)<\/p>\n

var PAGER =When(
\n$feature.alert == ‘GREEN’, “PAGER GREEN”,
\n$feature.alert == ‘YELLOW’, “PAGER YELLOW”,
\n$feature.alert == ‘ORANGE’, “PAGER ORANGE”,
\n$feature.alert == ‘RED’, “PAGER RED”,
\n“NO PAGER”)<\/p>\n

TIME + ” ” + MAG + ” – ” + PAGER<\/p>\n

Please Note: When you copy the above text and paste it into Arcade you will have to modify the ‘single’ and “double” quotes.\u00a0 They will come in formatted curly and you need to make them straight.<\/em><\/p>\n

It will look like:<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"image","image":{"ID":392952,"id":392952,"title":"eem_18_earthquakes9","filename":"eem_18_earthquakes9.jpg","filesize":55717,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes9","alt":"Image of the Arcade code to classify the earthquakes by Time, Magnitude, and Alert Level.","author":"8492","description":"","caption":"","name":"eem_18_earthquakes9","status":"inherit","uploaded_to":390782,"date":"2018-12-28 03:44:57","modified":"2019-02-02 03:42:42","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":723,"height":553,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9-300x229.jpg","medium-width":300,"medium-height":229,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9.jpg","medium_large-width":723,"medium_large-height":553,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9.jpg","large-width":723,"large-height":553,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9.jpg","1536x1536-width":723,"1536x1536-height":553,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9.jpg","2048x2048-width":723,"2048x2048-height":553,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9-608x465.jpg","card_image-width":608,"card_image-height":465,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9.jpg","wide_image-width":723,"wide_image-height":553}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2018\/12\/eem_18_earthquakes9.jpg"},{"acf_fc_layout":"content","content":"

 <\/p>\n

What this code is saying is:<\/p>\n

MAG
\nWhen (the magnitude is greater than or equal to 4 and less than 5, give it the name “Mag 4-4.9”,
\nWhen the magnitude is greater than or equal to 5 and less than 6, give it the name “Mag 5-5.9”,
\nWhen the magnitude is greater than or equal to 6 and less than 7, give it the name “Mag 6-6.9”,
\nAnything else greater than or equal to 7, give it the name “Mag >=7”)<\/p>\n

TIME
\nWhen (the hours old is less than 25, give it the name “Past 24 hr”,
\nWhen the hours old is greater than 25 but less than 145, give it the name “Past Week”,
\nAnything else give it the name “Past 3 Months)<\/p>\n

ALERT
\nWhen (the alert equals “GREEN”, give it the name “PAGER GREEN”,
\nWhen the alert equals “YELLOW”, give it the name “PAGER YELLOW”
\nWhen the alert equals “ORANGE”, give it the name “PAGER ORANGE”
\nWhen the alert equals “RED”, give it the name “PAGER RED”,
\nAnything else give it the name “NO PAGER”)<\/p>\n

Put them all together and they are named: TIME + space in between words + MAG + space in between words + PAGER<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"image","image":{"ID":428392,"id":428392,"title":"eem_18_earthquakes190","filename":"eem_18_earthquakes190.jpg","filesize":319606,"url":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190.jpg","link":"https:\/\/www.esri.com\/arcgis-blog\/products\/arcgis-living-atlas\/mapping\/one-symbol-from-multiple-fields-in-arcade\/eem_18_earthquakes190","alt":"One 50-foot (15 m) section of the San Francisco\u2013Oakland Bay Bridge collapsed during the 1989 Loma Prieta earthquake.","author":"8492","description":"One 50-foot (15 m) section of the San Francisco\u2013Oakland Bay Bridge collapsed during the 1989 Loma Prieta earthquake.","caption":"One 50-foot (15 m) section of the San Francisco\u2013Oakland Bay Bridge collapsed during the 1989 Loma Prieta earthquake.","name":"eem_18_earthquakes190","status":"inherit","uploaded_to":390782,"date":"2019-02-02 03:21:57","modified":"2019-02-02 03:27:57","menu_order":0,"mime_type":"image\/jpeg","type":"image","subtype":"jpeg","icon":"https:\/\/www.esri.com\/arcgis-blog\/wp-includes\/images\/media\/default.png","width":1024,"height":692,"sizes":{"thumbnail":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190-150x150.jpg","thumbnail-width":150,"thumbnail-height":150,"medium":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190-300x203.jpg","medium-width":300,"medium-height":203,"medium_large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190-768x519.jpg","medium_large-width":768,"medium_large-height":519,"large":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190-1024x692.jpg","large-width":1024,"large-height":692,"1536x1536":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190.jpg","1536x1536-width":1024,"1536x1536-height":692,"2048x2048":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190.jpg","2048x2048-width":1024,"2048x2048-height":692,"card_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190-688x465.jpg","card_image-width":688,"card_image-height":465,"wide_image":"https:\/\/www.esri.com\/arcgis-blog\/app\/uploads\/2019\/01\/eem_18_earthquakes190.jpg","wide_image-width":1024,"wide_image-height":692}},"image_position":"center","orientation":"horizontal","hyperlink":"https:\/\/www.flickr.com\/photos\/sanbeiji\/220646211\/in\/photostream\/"},{"acf_fc_layout":"content","content":"

 <\/p>\n

Applying the Expression<\/h2>\n

We have our expression to classify the earthquakes by Time, Magnitude, and Alert Level.\u00a0 Watch the short video to see how to apply it and rearrange the new classifications.<\/p>\n

 <\/p>\n"},{"acf_fc_layout":"youtube","start_time":"0","end_time":"","youtube_video_url":"