SIO 15 Lecture 21: SIO LECTURE 21

• School: UCSD
• Department: Scripps Institution of Oceanography
• Course: SIO 15
• Professor: Gabi Laske

Document Summary

Lecture 21: long and short term climate changes. Western pacific ocean has highest number of hurricanes. Nitrogen is the major constituent of earth"s atmosphere. During the cretaceous (80 mio yrs ago) earth was warmer than today. Climate change happening rapidly and recent change is caused by human impact. Current level of co2 highest in 800,000 years (evidence from ice cones) External changes: impacts, change in solar output, changes in earth"s position relative to sun. Internal changes: changes in atmosphere and ocean chemistry, ocean circulation, volcanism, continental drift. 200 times more co2 than ch4, ch4 traps heat 20 times stronger. Cfcs anthropogenic greenhouse gases, not natural, destroy stratospheric ozone layer, phased out through 1987 montreal protocol. Positive radiative forcing = warming, negative radiative forcing = cooling. Ozone in the troposphere (greenhouse gases) = positive radiative forcing. Ozone in stratosphere has negative forcing (captures uv radiation)