Geology GEOL-G 130 Lecture Notes - Lecture 6: Sea Ice, Glacial Motion, Global Warming
Document Summary
History of antarctic ice: reflectivity, reflected light keeps earth cool, absorbed light contributes to warming. Gaining sea ice in the arctic: sea ice. 150 million people live within 1m of sea level. Sea level over time: sea level lows= ice ages, rise is rapidly at the end of an ice age, falls slowly as ice sheets grow, intervals of (cid:498)modern(cid:499) values of sea level-getting higher, repeating changes. 100,000 years ice sheet size is a major control on global sea level. Formation and growth of glaciers: firn is granular snow. A glacier is like a bank account. When the ice sheet shrinks, sea level rises. Parts of a glacier or ice sheet: zone of accumulation. If there"s greater ablation then accumulation there"s a negative balance and the ice. Over one year there"s more mass loss/ablation than accumulation. Glacial advance: accumulation is greater than ablation. Glacial retreat: accumulation is less than ablation.
