Correctly Quantifying "Pooling" Methane

This plume is a sidler – sidling up next to this separator equipment, likely due to swirling winds in the wind shadow of the equipment. You might be tempted to ask if “pooling” gas like this, building up before being swept away, affects the quantification of the emission source. In fact it doesn’t since we are looking at the plume’s gas volume within this field of view, and using wind information to compute the flux of gas per unit time exiting the scene that we are imaging. Said another way, the buildup of the ”pool” of gas has come into equilibrium with the wind field sweeping it out of our field of view. The same is true with leaks trapped at ground level where the wind velocity approaches zero right near the ground, but the wind velocity increases geometrically with distance from the ground and gas gets swept out in a way so that the whole plume’s gas volume maintains equilibrium if the source is constant.