1. A method for detecting chemicals with a gas chromatography sensor comprising: determining a similarity sequencing scheme for the gas chromatography sensor, wherein the similarity sequencing scheme comprises a time sampling rate profile configured such that an early-eluting chemical and a late-eluting chemical elute over a similar sampling width; fitting the time sampling rate profile to a slow elution profile for the early-eluting chemical and a fast elution profile for the late-eluting chemical such that the early-eluting chemical and the late-eluting chemical elute over the similar sampling width; receiving an ambient air sample; concentrating the ambient air sample; providing the concentrated sample to at least one gas chromatography (GC) column; and detecting chemical elution from the at least one GC column in a series of similarity sequenced samples according to the similarity sequencing scheme; and determining a concentration of at least one chemical in the ambient air sample based on the series of similarity sequenced samples.