Abstract: The disclosure relates to an emission detector for monitoring methane emissions at one or more industrial facilities. The emission detector includes: an enclosure that supports a plurality of sensors, wherein the enclosure is configured to permit atmospheric gas to flow by diffusion into space at or near the plurality of sensors, wherein the plurality of sensors include at least one atmospheric sensor configured to measure atmospheric properties of the atmospheric gas that flows into the space at or near the plurality of sensors as well as at least one gas sensor configured to measure concentration of methane in the atmospheric gas that flows into the space at or near the plurality of sensors.

Abstract: Systems and methods are described for developing a model to predict humidity (relative, absolute) values inside a closed housing with an absorbent filter. In an example, a methane sensor that includes an internal atmospheric sensor and an external atmospheric sensor can be placed at a site. A computing device can use measurements from the atmospheric sensors to calculate predicted relative and absolute humidity values inside the methane sensor. The computing device can train a gaussian process regression model to calibrate sensor data based on the external temperature and humidity. When the model predicts the ambient methane within a predetermined degree of allowance, the model can be applied to live readings from methane sensors in the field.