Polar regions

Two Regions Arctic Circle About 66 N of equator Ocean surrounded by land Regions of North America, Greenland, Iceland, Siberia, N. Europe Marine ice Also has larger diversity of flora and fauna d/t unique geography Antarctica 66 S of equator Composed only of antarctica continent entirely surrounded by the Southern ocean Has both marine and land ice Also has more diverse fauna than expected for such a harsh environment

Arctic Circle

Antarctica

Arctic Circle Marine environment loss of sea ice -Albedo effect (positive feedback on warming) -Thermohaline circulation (increasing freshwater into ocean) -Polar amplification Terrestrial environment Permafrost -Melting causes sea level rise -Co2, CH4 release (Positive feedback)

Arctic permafrost Layer of permanently frozen soil, sediment, or rock (sometimes underneath an active layer)

Arctic Marine diversity and food web

Arctic Ponds and Lakes Rests on permafrost Disappearance or significant by ~11% over past 25 years ics.htm ics.htm Causes of disappearance

Antarctica

-Large continent twice size of Australia -98% of it is frozen -Divided by Transantarctic Mountains -Ecological diversity under threat

Antarctic Biodiversity Isolated continent (geography and temperature) Regional variations (Western, Southern Peninsula, Eastern)with highest diversity in the North Examples

Notothenioid fishes

Other species

Effects of temperature Stenothermal Direct effects versus indirect effects