Presentation on theme: "8/28/2002 Ozone Abundance in Earth-like Planets NTNU Earth Science Department Shung-wen Hsu Supervisor ： Gu, Pin-Gao."— Presentation transcript:
8/28/2002 Ozone Abundance in Earth-like Planets NTNU Earth Science Department Shung-wen Hsu Supervisor ： Gu, Pin-Gao
8/28/2002 Outline Introduction About OZONE LAYER The SIMULATION Comparing to the Franck Selsis Paper Conclusion & Future work Introduction
8/28/2002 Early Earth Atmosphere The atmosphere formed when the core, mantle, and crust differentiated. DEGAS with differentiate -- gas released form the Earth. The original composition in the early Earth atmosphere is : H 2 O 、 H 2 、 HCl 、 CO 、 CO 2 、 N 2 …etc
8/28/2002 Index of Life? How to find the other life on other planets? By oxygen? We can not be detected oxygen in planet spectra, but we can detect Ozone. Finding creatures live on the land…?
8/28/2002 The Stratosphere Altitude : 10 ~ 50 km Stable inversion layer Thermosphere Mesosphere Stratosphere Troposphere Locate at the stratosphere Heating the atmosphere and cause the inversion layer. The Ozone layer
8/28/2002 The Formation of Ozone Layer Chapman Equations Reaction rate : Fast : (1) 、 (3) Slow : (2) 、 (4) Very slow : (5) Timescale between Chemistry and Transport (dynamical).
8/28/2002 The Formation of Ozone Layer II For simplify the equation, we take off the slow reaction. Finally, we got this : K1/k2 is an inverse ratio to temperature.
8/28/2002 Simulation Fortran program Isothermal Simulation Dynamic Equilibrium Simulation
8/28/2002 Isothermal Simulation Assume : 1.Each layer is well mixed. 2.Each layer is independent ( no vertical convection and heat transport). 3.The ozone do not heat or cool the atmosphere. 4.The radiation from the ground does not be considered. K1/k2 is an inverse ratio to temperature.
8/28/2002 F 、 G 、 K star spectra A Stellar Spectral Flux Library: 1150 - 25000 A (Pickles 1998)
8/28/2002 Different Stellar Spectra in Isothermal Simulation We can only find that the F2V star causes higher ozone at altitude above 30km. The O3 mixing ratio of G2V is almost the same with the K2V. => We can’t get information from isothermal simulation.
8/28/2002 Dynamic Equilibrium Simulation Assume : 1.Each layer is well mixed. 2.Each layer is independent. 3.The heating effect is caused by ozone only, and the cooling effect is caused by CO 2 only. And I assume heating is equal to cooling in this simulation. 4.The radiation from the ground does not be considered.
Heating & Cooling Rate Heating : caused from ozone absorb and transform UV into thermal energy. Cooling : caused from CO 2 thermal emission to the space.
8/28/2002 Dynamic Equilibrium Simulation Result I Highest temperature – 305k, 52km. The trend of the temperature maybe correct. The temperature difference between is much larger in the dynamic equilibrium simulation than a observed data. Temperature Profile -- Solar Flux
8/28/2002 Dynamic Equilibrium Simulation Result I
8/28/2002 K1/k2 is an inverse ratio to temperature. So, temperature is high, this effect will cause the [O3] drop, and oppositely, when the temperature is low, the [O3] will be more. This effect seems to dominate my simulation!!
8/28/2002 Paper of Franck Selsis DARWIN And The Atmosphere of Terrestrial Planets K-type,low temperature, high ozone F-type,High temperature, low ozone
8/28/2002 The Selsis Simulation Spectra of Planets
8/28/2002 Conclusion & Future Work A lot of aspects do not be considered in my simulation, Ex. Scattering 、 O3 cooling effect 、 catalytic reaction 、 incorrect UV flux…etc. Make the code complete, and expect the program could reflect the properties of earth-like planet atmosphere more precisely.
Evidence in Geology Banded iron accumulated between about 1.9 to 3.5 billion years ago. Banded iron – the mineral which have not oxidized completely. Banded iron can not be found in the rock younger than 1.9 billion year. Banded iron