glaciation Flashcards
what are the 3 milankovitch cycles?
eccentricity of orbit
axial tilt
precession
what do the milankovitch cycles cause?
long term climate change
what else is said to cause long term climate change too?
feedback mechanisms
whats positive feedback`?
amplify a small change
whats negative feedback?
diminish or make change smaller
what are the 7 different forms of ice mass?
ice sheet, ice field, ice cap, shelf, valley glacier, piedmont glacier, cirque glacier
whats the cyrosphere?
earths crust subject to temperatures below 0 degrees
whats meant by albedo?
reflective coefficient of a surface, ie being white
what is meant by calving?
breaking of ice chunks at the glacier snout to form ice bergs as the glacier reaches the ocean
whats thermohaline circulation?
global system of surface and deep water ocean currents driven by differences in temp and salinity between different areas of the ocean
what are short term causes of climate change?
solar forcing and volcanic activity
whats solar forcing?
amount of energy admitted by the sun depends on the amount of sunspots of suns surface caused by magnetic rain
what are stadial periods?
colder periods of time
what are instadial periods?
shorter hotter periods of time
what are warm based glaciers? (characteristics)
high altitude areas, water exists below as a liquid but below 0 degrees, this effects of pressure mean the glacier is prevented from freezing to its bed, rich debris in layers
signify sub glacier processes
