1. Section 3 Remote sensing of global change Ozone hole Global Change Instructor: Dr. Cheng-Chien LiuCheng-Chien Liu Department of Earth Sciences National Cheng Kung University Office: Building of Earth Sciences, room 30206 Voice: +886-6-2757575 ext. 65422 E-mail: ccliu88@mail.ncku.edu.tw Office hours: Monday 14:00 – 17:00, Wednesday 9:00 – 12:00 URL: http://mail.ncku.edu.tw./~ccliu88/http://mail.ncku.edu.tw./~ccliu88/ Last updated: 22 April 2005

2. Compositions of atmosphere  Constituents N 2 O 2 Ar CO 2, H 2 O, Methane, O 3, SO 2, CFC, …  Distribution and structure Temperature Ozone

3. Fig. 1 Fig. 1 Vertical structure of ozone concentration and temperature in the atmosphere. Source: http://140.115.123.30/gis/globalc/fig/05-01.gifhttp://140.115.123.30/gis/globalc/fig/05-01.gif

4. Ozone  Origin O 2 + hυ→O + O O+ O 2 + M → O 3 + M  Unit Dobson unit ( DU ) 1 DU = 10 -5 m @1atm Average O 3  300 DU = 0.3 cm @1atm

5. Ozone (cont.)  Merits ozone  absorb UV radiation http://svs.gsfc.nasa.gov/vis/a000000/a001600/a0 01603/moleculeC.movhttp://svs.gsfc.nasa.gov/vis/a000000/a001600/a0 01603/moleculeC.mov  Destruction CFC destruction  Ozone destruction http://svs.gsfc.nasa.gov/vis/a000000/a001600/a0 01603/moleculeA.movhttp://svs.gsfc.nasa.gov/vis/a000000/a001600/a0 01603/moleculeA.mov http://svs.gsfc.nasa.gov/vis/a000000/a001600/a0 01603/moleculeB.movhttp://svs.gsfc.nasa.gov/vis/a000000/a001600/a0 01603/moleculeB.mov

6. Ozone (cont.)  Consequences of losing ozone Different absorption of UV-A, UV-B, UV-C UV-C UV-B   Skin cancer, immune system, reptile eggs, photosynthesis, production, phytoplankton UV-A Biology > Climate

7. Fig. 2 The height to the ground that the solar radiation ranged from 140 to 340 nm can penetrate in the atmosphere. Source: http://140.115.123.30/gis/globalc/fig/05-10.gifhttp://140.115.123.30/gis/globalc/fig/05-10.gif Fig. 2.2.1

8. Remote sensing techniques for studying ozone hole  Total Ozone Mapping Spectrometer http://toms.gsfc.nasa.gov/

9. Remote sensing techniques for studying ozone hole (cont.)  Mission Nimbus-7 (1978/10 – 1993/5) Meteor-3 (1991/8 – 1994/11)  A short video of the Meteor-3 launch from the Plesetsk facility in Russia http://toms.gsfc.nasa.gov/m3toms/images/m3launch2.mpg http://toms.gsfc.nasa.gov/m3toms/images/m3launch2.mpg ADEOS (1996/7 – 1997/6) Earth Probe (1996/7 – present)

10. Remote sensing techniques for studying ozone hole (cont.)  Principle http://code916.gsfc.nasa.gov/Public/Space_base d/sbuv/oz_meas.htmlhttp://code916.gsfc.nasa.gov/Public/Space_base d/sbuv/oz_meas.html 12 bands from 255 nm to 340 nm  Penetrate to the ground  total column ozone  312.5 nm, 317.5 nm, 331.2 nm and 339.8 nm  Take two band ratio (weakly and strongly absorbed)  Not penetrate to the ground  ozone vertical profile  255 – 306 nm   penetration   Wavelengths scan  attitude scan

11. Remote sensing techniques for studying ozone hole (cont.)  Measurements The evolution of the ozone hole over Antarctica (1979 – 1999) made by Nimbus-7 + Meteor-3 and Earth Probe  http://svs.gsfc.nasa.gov/vis/a000000/a000700/a000710/a0007 10.mpg http://svs.gsfc.nasa.gov/vis/a000000/a000700/a000710/a0007 10.mpg Ozone in the northern and southern hemispheres as measured by Earth Probe TOMS from 7/26/1996 to 11/4/2001  http://svs.gsfc.nasa.gov/vis/a000000/a002200/a002284/a0022 84.mpg http://svs.gsfc.nasa.gov/vis/a000000/a002200/a002284/a0022 84.mpg

12. Fig 3 Fig. 3 Earth Probe TOMS Total Ozone September 16, 2000 Source: http://toms.gsfc.nasa.gov/multi/recent_ozone91200.gifhttp://toms.gsfc.nasa.gov/multi/recent_ozone91200.gif

13. Fig 4 Fig. 4 Ozone hole size. Source: http://www.gsfc.nasa.gov/gsfc/earth/pictures/20020926ozonehole/avg_size_o3hole79- 01_bw.jpghttp://edc.usgs.gov/products/satellite/avhrr.html http://www.gsfc.nasa.gov/gsfc/earth/pictures/20020926ozonehole/avg_size_o3hole79- 01_bw.jpg

14. Questions  Why the ozone hole is only found in Antarctica?