Dr. Jacob Lowenstern leading a field trip Yellowstone National Park
By Yellowstone Volcano Observatory
2017 (approx.)

Detailed Description
Dr. Jacob Lowenstern, Scientist-in-Charge of the Yellowstone Volcano Observatory during 2002-2017. In this photo, he's leading a field trip in Yellowstone National Park with a group of international volcanologists.
Sources/Usage
Public Domain.