Either by uploading csv data or software that can recognize data in an existing heat map image or pdf file
Heat maps on google maps could represent the answers to so many questions by cross referencing data from all over the world
https://www.investorville.com.au/ has a map of Australian with median prices, rental yield, capital growth data embedded in the map
If we could do that globally it would encourage growth and create jobs all over the world.
Heat maps can represent data visually global warming, water quality, population growth and any number of questions you could ask where data that relates locally has a certain value but if it was linking together to create a global resource it would be more valuable still.
If you were research a dinosaur a heat map could show you along side wiki where fossils are found and where bones are in a museum you could visit
For every plant and animal species a heat map could should where they are located and in what numbers
By cross referencing data countless other questions could be answered