Hello … Welcome All

1. Hello … Welcome All

2. Origin And Composition of Atmosphere Pro-seminar Presentation Techniques (Dr. Andreas Richter) Irshad Ahmad PEP, Universität Bremen

3. Content • History • Big Bang Theory • Primordial atmosphere • Composition (He,H) • Origin • Where He and H gone! • Secondary atmosphere • Composition • Origin • Formation of Oceans and life • Generation of different gases • Current atmosphere • Composition • Origin • Summary

4. History • Big Bang Theory • 13.7 billion years ago • Earth formed before 4.5 billion years ago • Solar nebula constructed atmosphere of the earth • Early atmosphere consist mostly of H and He http://www.uky.edu/Classes/PHI/100.401/bigbang/ http://www.dl-digital.com/astrophoto/Seagull-IC2177.htm

5. The very first atmosphere was consisted of mainly Hydrogen(H) and Helium(He) Earth got it from solar nebulas These gases were very light and escaped to space http://eps.berkeley.edu/cig/depaolo/eps102/PPT5_Condensation_Accretion.html First(Primordial) atmosphere

6. Composition CO2, H2O, SO2,CO, S2, N2, H2, CH4 , etc Origin volcanic outgassing Formation of Oceans and life Primordial heat dissipated to space Temperature lowered Condensation of water(rain) Impact of meteors Oceans and surface water Evolution of life Secondary atmosphere http://astro.physics.uiowa.edu/~clang/general_fall07/9nov07_notes.pdf

7. Generation of different gases Most of the gases produced by volcanic eruptions CO2 dissolved in oceans First cellular organism(Cyanobacteria) used CO2, CH4, NH3 and produced O2 O2 also came from photosynthesis, photochemical reaction Mary Sarcina/University College London    Fluorescence micrographs of cyanobacteria. About 2 billions years ago, cyanobacteria – oxygen-producing photosynthetic prokaryotes that used to be called blue-green algae – were responsible for launching the process that increased the concentration of atmospheric oxygen from less than 1 percent to about 20 percent today, making possible the evolution of humans and other animals. https://publicaffairs.llnl.gov/news/news_releases/2006/NR-06-03-09.html

8. http://ees2.geo.rpi.edu/abrajanoCourses/public_html/Lecture7.pdfhttp://ees2.geo.rpi.edu/abrajanoCourses/public_html/Lecture7.pdf http://ees2.geo.rpi.edu/abrajanoCourses/public_html/Lecture7.pdf Photosynthesis and Photochemical processes

9. Composition N2 (78%) O2 (21%) Remaining 1% includes Ar (0.9%), CO2 (0.03%) H2O (varying) Trace gases (H2, O3, CH4, CO, He, Ne, Kr, Xe) http://en.wikipedia.org/wiki/Earth's_atmosphere Current atmosphere

10. Reduction of CO2 CO2 dissolved in rainwater produced weak carbonic acid chemically reacts with rocks Produces carbonate compounds Earth’s Climate: Past and Future

11. Most of the gases released by Volcanic outgassing N2 is chemically inert and it couldn`t escaped to space O2 come from photosynthesis and photolysis as discussed before O3 came from photodissociation of O2 O2+hv------- O+O O2+O+M----O3+M WMO Report 2003 Generation of different gases

12. Argon(Ar) Added to the atmosphere by radioactive decay of planet’s bedrocks. Aerosols (air pollutants) Came from natural (dust, sea spray etc) And human (industries, vehicles etc) activities http://www.spiegel.de/img/0,1020,904800,00.jpg

13. Primordial atmosphere H,He (solar nebula) H and He escaped to space Secondary atmosphere CO2, H2O, SO2,CO, S2, N2, H2, CH4 ,etc (volcanic outgasing) Cyanobacteria produced earlier Oxygen O2 Photosynthesis and photochemical processes produced oxygen Current atmosphere most of the CO2 was locked into the bedrocks Ozone came from photolysis of O2 http://ees2.geo.rpi.edu/abrajanoCourses/public_html/Lecture7.pdf Summary

14. Please protect the Atmosphere

15. Thanks for your attention Questions ??