Lecture23_EAS1600_Fall08 - EAS 1600 Introduction to...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: EAS 1600 Introduction to Environmental Sciences ____________________________ Lecture 23- Long-Term C Cycle ________________________________ There are two aspects of this cycle we will focus on: its relationship to the long-term stability of atmospheric O 2 ; and its role in long-term climate stability Oxygen and Carbon Dioxide Oxygen in the atmosphere was formed via photosynthesis However, CO 2 is going up in concentration therefore O 2 must be going down due to combustion CH 2 O + O 2 CO 2 + H 2 O Will oxygen levels be depleted eventually? ctually, scientists believe that atmospheric O 2 is subject to an ctive stabilization mechanism. Atmospheric O 2 is believed to have been constrained over past few hundred million years to the fire window hy? How? It is quite possible that egative feedbacks exist in arth System act to stabilize tmospheric oxygen. At least two mechanisms have been roposed Atmospheric Oxygen Deep-ocean Oxygen Burial of Organic C in ocean sediments (-) For example, controls on the burial of organic carbon in ocean ediments : r controls on forest fires Atmospheric Oxygen Forest Fires Storage of Organic C in soils (-) an you figure out why these mechanisms stabilize O 2 ? Possible question on Exam!) ow we turn to our second topic: he C-Cycle and Long-Term Climate Stability e begin by considering The faint sun paradox When Earth formed 4.6 bya, olar luminosity was about 0% of its present value From Kasting et al., Scientific American , 258 , 90-97, 1988 Things you should know ......
View Full Document

This note was uploaded on 02/08/2011 for the course EAS 1600 taught by Professor Jimstjohn during the Spring '08 term at Georgia Institute of Technology.

Page1 / 16

Lecture23_EAS1600_Fall08 - EAS 1600 Introduction to...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online