Slide 1Slide 2Why were automakers suing California?Why were automakers suing California?Slide 5Slide 6Slide 7Vertical Layers of the Lower AtmosphereSlide 9videoSlide 11Slide 12Slide 13Slide 14Absorption of Ultraviolet Radiation by OzoneSlide 16Slide 17Slide 18Ozone Hole RecipeTotal Ozone Content from Nimbus 7 TOMSTotal Ozone Content from Nimbus 7 TOMSTotal Ozone Content from Nimbus 7 TOMSTotal Ozone Content from Nimbus 7 TOMSTotal Nimbus 7 TOMS Ozone Content fromTotal Ozone Content from Nimbus 7 TOMSSlide 26Slide 27Class ActivityWhere are the highest concentrations of ozone located?Slide 30Past EventsCauses of DepletionEarly concerns of ozone depletionHistory of Ozone Depletion: connection between human and natureSlide 36Slide 37videoOzone Hole RecipeEffects of Ozone DepletionWhat is being done about ozone depletion?Slide 43Is the Montreal Protocol working?Slide 45Slide 47Slide 48Slide 50Slide 52Slide 53Slide 54The Antarctic ozone hole develops duringGlobal ozone values are expected to recover in the nextSlide 57Professor Menglin JinSan Jose State University, Department of MeteorologyMET 112 Global Climate ChangeOzone Hole and Human ConnectionConnection between people to climateExamples 1: http://www.youtube.com/watch?v=GSws08S9mQEExample 2: CA AutomakersWhy were automakers suing California?1. For regulating emissions of CFCs2. For limiting number of SUV sales emissions of nitrogen3. For limiting number of minivan sales.4. For regulating GHG emissionshttp://www.nytimes.com/2006/09/21/business/21auto.htmlWhy were automakers suing California?1. For regulating emissions of CFCs2. For limiting number of SUV sales emissions of nitrogen3. For limiting number of minivan sales.4. For regulating GHG emissionshttp://www.nytimes.com/2006/09/21/business/21auto.htmlSuggest to read: The Ozone Hole http://www.theozonehole.com/http://www.nas.nasa.gov/About/Education/Ozone/chemistry.htmlBasic chemistry of ozone depletionVertical Layers of the Lower AtmosphereOzoneOzone is found in boundary layer as well as in stratosphere layer. The former is one of greenhouse gases.video•http://www.met.sjsu.edu/metr112-videos/MET%20112%20Video%20Library-MP4/ozone%20hole%20and%20human%20connection/•Ozone Sequence since 1979What is the seasonality of O3 in stratosphereOzone-1.mp4Why Ozone occur? Where? When?Lowest value of ozone measured by TOMS each year in the ozone holeOzone Hole: Ozone depletion describes two distinct, but related observations: a. a slow, steady decline of about 4 percent per decade in the total amount of ozone in Earth's stratosphere since the late 1970s; and b. a much larger, but seasonal, decrease in stratospheric ozone over Earth's polar regions during the same period. The latter phenomenon is commonly referred to as the ozone hole. In addition to this well-known stratospheric ozone depletion, there are also tropospheric ozone depletion events, which occur near the surface in polar regions during spring. http://en.wikipedia.org/wiki/Ozone_depletionThis figure was prepared by Robert A. Rohdeultraviolet light (UV light) harmful UVB wavelengths (270–315 nm)Absorption of Ultraviolet Radiation by OzoneOzone Formation through Splitting of Oxygen by Ultraviolet RadiationOzone Hole: Reductions of up to 70% in the ozone column observed in the austral (southern hemispheric) spring over Antarctica and first reported in 1985 (Farman et al 1985)Formation and destruction of ozoneSunlight is the major energy source for both making and destroying stratospheric ozone: When an Oxygen molecule absorbs a photon of light with a wavelength shorterthan 200 nanometers (1 billionth of a meter) the energy splits the molecule into two Oxygen atoms. One of these atoms can react with another Oxygen molecule to form an Ozone molecule. Up to 98% of the sun's high-energy ultraviolet light (UV-B and UV-C) are absorbed by the destruction and formation of atmospheric ozone. The global exchange between ozone and oxygen is on the order of 300 million tons per day. http://www.nas.nasa.gov/About/Education/Ozone/chemistry.htmlOzone Hole RecipeIngredients:•Chlorine gas•Cold Temperatures (~-80C)Instructions:•Allow cold temperatures to form Polar Stratospheric Clouds (1-2 weeks).•Allow time for polar stratospheric clouds to convert chlorine gas into ozone destroying chemicals. (1 month)•Bake ingredients with sunlight.•bingo, a delicious ozone hole!Science interpretation•Chlorine gas is abundant in atmosphere due to CFC’s•Cold Temperatures (~-80C) only occur over Antarctica during the cold winter.•Polar Stratospheric Clouds allow ozone friendly chlorine to be transformed into ozone destroying chlorine. •Ozone depletion then starts when sun returns to Antarctica in the spring•Ozone hole grows from late August through till October.Dobson Units0°60°E120°E180°60°W120°W180°March 1990Halley BayTotal Ozone Content from Nimbus 7 TOMS5004654303952902552201851501153600° 60 12060120180June 1990Total Ozone Content from Nimbus 7 TOMS180September 1990Total Ozone Content from Nimbus 7 TOMSDobson Units32550046543039529025522018515011536090°N60°N30°N0°30°S60°S90°SDecember 1990Total Ozone Content from Nimbus 7 TOMSAugust 19900°90°W180°180°90°W90°E90°E0°60°S60°S60°S60°S30°S30°S30°S30°SSeptember 1990October 1990November 1990Total Nimbus 7 TOMS Ozone Content from 500465430395290255220185150115360October 19790°90°W180°180°90°W90°E90°E0°60°S60°S60°S60°S30°S30°S30°S30°SOctober 1982October 1985October 1988Total Ozone Content from Nimbus 7 TOMSGlobal OzoneHuman activityClimate and WeatherClimate ChangeScience UnderstandingPolicy Makersuccessful example is Response to Ozone HoleClass Activity•When Ozone occur?•Why Ozone occur?•Do you think Ozone hole related to Human activity? How•What people can do to avoid ozone hole?Where are the highest concentrations of ozone located?1. In large cities2. The stratosphere3. The troposphere4. Near volcanoesOzone DepletionTopicsHistory of Ozone DepletionThe Ozone Hole: what, where, why?Ozone into the futurePast Events•Deepest ozone hole:–September 30, 1994–Levels fell to 73 DU•Largest ozone hole:–September 1, 2006–10.6 million sq. miles–Antarctica•(5.4 million sq. miles)Causes of Depletion•Chlorofluorocarbon (CFC) •Presence of UV, Chlorine dissociates from (CFC’s)–Produces chlorine radicals–Decompose ozone molecules•Polar stratospheric clouds–Occur in winter at -80 °C–CFC