Steph Abegg sent us several aerial views into Sherman Crater taken on February 26. John Scurlock piloted the plane. The photos show once again that even in the depths of winter, fumarolic heat flow is sufficient to keep a fair amount of the talus and rock in the fumarole fields bare of snow.
Sherman Crater has a number of distinct fumarole fields, each containing dozens of separate gas vents. The fumarole fields have moved about, coalesced, or separated over the past few decades.
Here’s a link to Steph’s photo website.
Melissa Park mapped the fumarole for her Masters thesis at WWU. These photos by Steph bear out Melissa’s designation of three levels of heat intensity in the Sherman fumarole fields. She designated these types (see map below):
Type A, snow free year-round, type B: snow free in the summer and type C: snow-covered year-round. We estimate the approximate size and location of these thermal grounds based on aerial photographs and the above background orthographic imagery from July 2009 in ArcGIS. Background photo by NAIP, digital orthographic imagery, 2009