Search results
Results from the WOW.Com Content Network
The maximum frost depth observed in the contiguous United States ranges from 0 to 8 feet (2.4 m). [1] Below that depth, the temperature varies, but is always above 0 °C (32 °F). Alternatively, in Arctic and Antarctic locations the freezing depth is so deep that it becomes year-round permafrost, and the term "thaw depth" is used
Watersheds of Illinois is a list of basins or catchment areas into which the State of Illinois can be divided based on the place to which water flows.. At the simplest level, in pre-settlement times, Illinois had two watersheds: the Mississippi River and Lake Michigan, with almost the entire State draining to the Mississippi, except for a small area within a few miles of the Lake.
Northern Illinois is dominated by the Chicago metropolitan area, including the city of Chicago, its suburbs, and the adjoining exurban area into which the metropolis is expanding. The " collar counties " are the five counties that surround the centrally located Cook County in the Chicago metropolitan area: DuPage County, Kane County, Lake ...
These basins, termed the Illinois Basin and Michigan Basin, allowed for extensive deposition of sedimentary rock during the Palaeozoic Era. [2] The Illinois Basin is a northwest–southeast asymmetrical structural basin that is filled with more than 4000 meters of Paleozoic sedimentary rocks. The basin covers most of Illinois, and extends into ...
Most frost quakes are associated with minor snow cover on the ground without a significant amount of snow to insulate the ground (i.e., less than 6 inches (15 cm)) A rapid temperature drop from approximately freezing to near or below −18 °C (0 °F), which ordinarily occurred on a timescale of 16 to 48 hours.
Permafrost temperature profile. Permafrost occupies the middle zone, with the active layer above it, while geothermal activity keeps the lowest layer above freezing. The vertical 0 °C or 32 °F line denotes the average annual temperature that is crucial for the upper and lower limit of the permafrost zone, while the red lines represent seasonal temperature changes and seasonal temperature ...
Wolf Lake is an 804-acre (325.4 ha) lake that straddles the Indiana and Illinois state line near Lake Michigan. [3] It is smaller than it was prior to settlement by European colonizers because of infilling for development around the edges.
Illinois averages around 50 days of thunderstorm activity a year which put it somewhat above average for number of thunderstorm days for the United States. Illinois is vulnerable to tornadoes with an average of 54 occurring annually, which puts much of the state at around 9.7 tornadoes per 10,000 square miles (30,000 km 2) annually.