The USGS has defined Deserts as environments where: (1) Rainfall is less than 25.4 cm (10 in) per year; (2) Evaporation exceeds actual rainfall; and (3) Temperatures are hot. Death Valley is a desert because the average rainfall is 4.83 cm (1.9 in) per year; evaporation is 381 cm (150 in) per year; and temperatures exceed 48.8 degrees Celsius (during summer months).
Death Valley has contrasting areas of extremes due to continuous drought conditions and record summer high temperatures. One such area is BadWater Basin. According to the National Park Service, BadWater Basin is 85.5 meters (282 ft) below sea level and was once covered with ocean water. Evidence of this can be observed by the vast amount of salt deposits in and covering the soil in this area as far as the eye can see. BadWater Basin provides an excellent real world connection to earth science because of the varying landforms, environments and evidence of geologic change. Location: Death Valley National Park. Author: Karl Spencer.
Erosion of rock formation due to wind and rain. Vocabulary connections – Erosion, sandstone and rock. Location: Valley of Fire State Park. Author: Karl Spencer.
Aerial view of Glaciers
According to the National Park Service (NPS), the wilderness of Glacier Bay includes tidewater glaciers, snow-capped mountain ranges, ocean coastlines, deep fjords and freshwater rivers and lakes.
What makes this wilderness unique is the role glaciers have played in this environment for at least the last seven million years. Most glaciers in the bay are experiencing significant retreat, thinning or stagnation, all giving rise to ecological succession. The succession processes are so evident in the park, that it offers various opportunities for scientific observation for geologists, plant ecologists and other scientists to study this dynamic environment. Location: Glacier Bay National Park. Author: Karl Spencer.
Freshwater lake area as an ecological SYSTEM. Location: Lake Mead in Nevada. Author(s): Karl Spencer.