Making invisible gas leaks visible

<img width=“750” height=“494” src=“https://i1.wp.com/flowingdata.com/wp-content/uploads/2019/12/Methane-leaks.png?fit=750%2C494&ssl=1" class=“attachment-medium size-medium wp-post-image” alt=“” srcset=“https://i1.wp.com/flowingdata.com/wp-content/uploads/2019/12/Methane-leaks.png?w=2104&ssl=1 2104w, https://i1.wp.com/flowingdata.com/wp-content/uploads/2019/12/Methane-leaks.png?resize=750%2C494&ssl=1 750w, https://i1.wp.com/flowingdata.com/wp-content/uploads/2019/12/Methane-leaks.png?resize=1090%2C71 …