EARTH 10 Lecture Notes - Lecture 14: Marine Isotope Stage, Little Ice Age, Weddell Sea
Document Summary
Isotope : same element with same # of protons and electrons, but different neutrons in nuclei. Marine isotope stage = period of alternation warm and cool periods in the earth"s paleoclimate. > variations of o2 isotopes used as proxy for global temp. change. It"s growing increases acidity of the oceans ocean acidification (30%+ in 250 years: solar output = bond, sunspot, and milankovitch cycles. Bond cycles ~3 kyr cycles (north atlantic ice rafting events) Sunspot cycles ~11yr (more sunspots and more solar energy released) Early and mid-holocene warmer in aa. Little ice age (b/t 1300-1870 in europe and n. america in winters) Aa cooler and stormier ~2 celsius colder on surface. El nino : periods of warmer ocean temp. along equatorian coast. In aa, high pressure over amundsen and bellingshausen seas less sea ice. Cools the earth with ash and aerosols into the stratosphere reflect radiation back into space.