From Wikimedia Commons, the free media repository
|This image is in the public domain in the United States because it contains materials that originally came from web cameras operated by the Alaska Volcano Observatory (AVO), an agency associated to United States Geological Survey. Web cameras of the AVO are United States government property and are therefore in the public domain in the US. AVO requests, as a courtesy, to credit them and USGS.|
An official from AVO has clarified that webcams are government property and images taken through them are therefore in the public domain in the US.