Geyser Snow
August 28, 2018
Photographer: Glenn McCreery
Summary Author: Glenn McCreery
Featured above is the Norris Geyser Basin in Yellowstone National Park. In the early spring you can often see geysers, the hottest features in Yellowstone, surrounded by snow, while the snow cover on the surrounding terrain has long since melted. This is because, with sub-freezing air temperatures, the geysers produce their own snow, which piles up to higher depths, and thus lasts longer than the just the snow falling from atmospheric clouds.
Both water and water vapor (steam) are ejected in geysers. The water ejected is superheated well above boiling point. Due to the Yellowstone Plateau's high elevation, the average boiling temperature at the geyser basins is 199 F (93 C). A typical geyser steam temperature can reach 350 F (177 C) or higher. The hot water quickly evaporates when it hits the much colder and drier ambient air. Snow will form when water vapor freezes on minute particles in the air stream, creating a cloud of ice crystals. As the individual ice crystals are swept through the vapor cloud, water vapor continues to freeze on them until they're big enough to fall to the ground. Photo taken on May 2, 2014.
Photo Details: Canon 5D II camera with Canon 24-105mm f:4.0 L zoom lens; set at 35 mm; ISO 160; 1/320 sec. exposure; f:11; Minor adjustments in Photoshop CS5.