Lec17 - ATM 6 Lecture#17 Stratospheric Ozone Depletion or"The Ozone Hole Part I Strat O3 Characteristics and Biological Effects of UV Radiation

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 1 ATM 6, Lecture #17 Cort Anastasio Atmospheric Science Program University of California - Davis Stratospheric Ozone Depletion or “The Ozone Hole” Part I: Strat. O 3 Characteristics and Biological Effects of UV Radiation Note: figures not from Turco are from “Twenty Questions and Answers About the Ozone Layer”, World Meteorological Organization, David Fahey, Lead Author, 2003 2 What is Ozone? • There are three major forms (“allotropes”) of oxygen in our atmosphere – Oxygen atoms (O); Reactive atoms needed to make ozone – Molecular oxygen (O 2 ); Very stable and needed for life – Ozone (O 3 ); Fairly reactive and absorbs UV light • The ozone layer in the stratosphere was fully formed ~ 1 billion years ago – Oxygen released by green plants was broken up by sunlight to form O and then O 3 : 1. Green plants + CO 2 + H 2 O + light O 2 2. Transport of O 2 from troposphere to stratosphere, followed by… 3. O 2 + light O + O 4. O + O 2 O 3
Background image of page 1

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

View Full DocumentRight Arrow Icon
2 3 Vertical Distribution of Ozone • ~ 90% of Earth’s O 3 is in stratosphere, ~ 10% in troposphere • Tropospheric ozone (“smog”) – “Bad” because ____________ – Levels have been increasing b/c of human emissions of NO x and RH – Max. concentrations ~ 0.1 - 0.2 ppmv • Stratospheric ozone (“ozone layer”) – “Good” because it blocks most harmful UV-B from reaching Earth’s surface – Levels have been decreasing b/c of human emissions of halocarbons – Max. concentrations ~ 10 - 20 ppmv – Ozone layer is at altitude of ~ 10 - 25
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/22/2008 for the course ATM 006 taught by Professor Anastasio during the Fall '07 term at UC Davis.

Page1 / 6

Lec17 - ATM 6 Lecture#17 Stratospheric Ozone Depletion or"The Ozone Hole Part I Strat O3 Characteristics and Biological Effects of UV Radiation

This preview shows document pages 1 - 3. Sign up to view the full document.

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