GEOL 150Lg Lecture Notes - Lecture 17: Global Warming, Marsupial, Climate Sensitivity
Document Summary
Cretaceous-teriary event: major exincion caused by slow climate change from volcanism and rapid change due to bolide impact, not permanent change, dinos went exinct, mammals survived. Measurements of 18o/16o raio reported as 18o used to reconstruct ocean temps: higher 18o: colder temperatures and more ice, lower 18o: warmer temperatures and less ice. India moving north into asia formed himalayas, changed climate. Paleocene world: temperature rose to a maximum around 50 million years ago, some rapid spikes in co2, some rapid temperature spikes, climate sensiivity at the high end of current esimates. Eocene temps were the highest in past 60 million years. 13c from fossil shells used to reconstruct ocean biologic producivity and sources of carbon entering the ocean. Carbon entering the ocean from methane and volcanoes have low. Lower 13c indicates lower biological producivity and/or methane or volcanic carbon entered the ocean.
