Sources of methane escaping

Sources of methane escaping from Arctic environments into the atmosphere. Methane measured in the September 2017 test by USGS scientists likely came from microbial breakdown of organic matter in thawing permafrost (source 1) or from deep geologic deposits (source 2). Methane hydrate (source 3), an ice-like form of water that contains methane molecules and releases them when its crystal structure breaks down, was not observed or expected in this study.