PPT-The Stratospheric Ozone Problem

First what is the ozone problem About 2 billion years ago Life on Earth was entirely singlecelled organisms living in the oceans when one type of bacteria Cyano began emitting Oxygen to the atmosphere . Stratospheric ozone: the natural cycle Produced in stratosphere by dissociation of oxygen atoms exposed to short-wave radiation Reaction accounts for most of adsorption of ultraviolet sunlight () as w 3. variability over recent decades: Stratospheric intrusions. , Asian pollution, and . climate. Meiyun Lin . Presented at Air Quality Research Subcommittee Meeting, Feb-19-2015 . Acknowledgements: . 3. variability over recent decades: . Stratospheric intrusions. , Asian pollution, and . C. limate Variability. Meiyun Lin. (Princeton University/GFDL). HTAP/WRAP Workshop, 13-May-2015 . Major challenges for western US air quality management. the progression of the Ozone hole over the antarctic from 1970 to 1997.. Some effects on plant and animal tissue as UV radiation increases. decrease in agricultural yields and a decrease in overall forest productivity. 9. th. ORM. Geneva, 14 May 2014. SAP Co-chairs. Ayit. é. -Lô. . Ajavon. (Togo). Paul Newman (USA). John Pyle . (UK). A.R. . Ravishankara. (USA). Chapter 4 of the upcoming assessment deals with “Stratospheric ozone changes and climate”.. by . David Gray. Scientific use. Background ozone. ozone present through natural or nonlocal sources. currently ranges from 20-45 ppb in North . America. Rising background ozone could mean non-attainment for much of North America. Tuesday, January 5. th. , 2015. Good up high, bad nearby. Troposphere:. Thinnest layer of atmosphere, 80% mass, almost all H. 2. O. 0.04 ppm O. 3. Stratosphere: 10 ppm O. 3. Characteristics of O. 3. Highly poisonous, strong odor, irritant, colorless gas. EVSC 1300. Spring 2016. Average. vertical. temperature. structure. of atmosphere. Average. vertical. temperature. structure. of atmosphere. NO. x. + VOCs + sunlight .  . Ground-level ozone. Figure18-9 p528. AND CURRENT STATUS. GLY 4241 - Lecture 8 . Fall, 2016. Mount Pinatubo Eruption, 1991. 2. 3. 1997 Montserrat Eruption. 4. Sulfur Dioxide Conversion. 5. Aerosol Optical Depth Analyses. BRW is Pt. Barrow, Alaska. 2. Ozone – Two Faces. Troposphere – Bad Ozone. Pollution . Photochemical smog. . Eye irritant. Stratosphere – Good Ozone. Blocks some UV radiation. Hole caused by depletion due. to ODC’s . Ozone Depletion(Chapter 25). Ozone Properties. Ozone (O. 3. ). is a triatomic form of oxygen found mostly in the lower half of the atmosphere. Highly reactive strong oxidant. Tropospheric pollutant produced by photochemical reactions. The . ozone layer or ozone shield . is a region of Earth's stratosphere that absorbs most of the Sun's UV radiation. . It contains high concentration of ozone (O3).. It is a pale blue gas at room temperature.. Nitrous . Oxide (N. 2. O). : The Dominant Ozone-Depleting Substance Emitted in the 21. st. . Century, A. . R. . Ravishankara, John S. Daniel, and Robert W. . Portmann, . SCIENCE. , . Vol. . 326, Pages: 123-125, 2009 (OCT 2. S. Weber. 1. , R. Ruhnke. 1. , P. Braesicke. 1. , C. Scharun. 1. 1. Institute of Meteorology . and Climate Research. Significance of stratospheric ozone (O. 3. ):. Plays a critical role in absorbing ultraviolet (UV) radiation emitted by the sun.