Space Debris/Ozone da 1 debris disad 2
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Ozone Link—GenericKeeping rocket launches low is key to maintain the ozone Ross and Zittel 7 (Martin N. Ross and Paul F. Zittel, 05/16/07,Martin N. Ross (left), Environmental Systems Directorate, leads research on the stratospheric impact of Air Force launch vehicles. He holds a Ph.D. from the University of California at Los Angeles in Earth and planetary sciences and has been with Aerospace since 1989. Paul F. Zittel (right), Remote Sensing Department, leads research on the radiative and chemical properties of rocket plumes and has conducted basic research in the areas of laser-induced chemistry, vibrational energy transfer, and cryogenic spectroscopy. He holds a Ph.D. in physical chemistry from the University of California at Berkeley and has been with Aerospace since 1976. Rockets and the Ozone Layer, http://www.aero.org/publications/crosslink/summer2000/01.html Protecting Earth's ozone layer remains an important environmental issue. Without this shielding layer, ultraviolet (UV) radiation would harm life on Earth. We hear alarming statistics on increasing incidences of skin cancer and other disorders that may be linked to a thinning of Earth's ozone layer. We know that the presence of chlorofluorocarbons (CFC)—chemicals used as solvents and refrigerants—and other industrial gases in the atmosphere is the major cause of ozone depletion. But what about exhaust from launch vehicles? Can the cumulative effect of emissions from rockets launched every three or four days from various launch sites around the globe significantly alter Earth's delicately balanced, natural sunscreen? Space transportation, once dominated by government, has become an important part of our commercial economy, and the business of launching payloads into orbit is expected to nearly double in the next decade. Each time a rocket is launched, combustion products are emitted into the stratosphere. CFCs and other chemicals banned by international agreement are thought to have reduced the total amount of stratospheric ozone by about 4 percent. In comparison, recent predictions about the effect on the ozone layer of solid rocket motor (SRM) emissions suggest that they reduce the total amount of stratospheric ozone by only about 0.04 percent. Chemical reactions result from rocket launches and hurt the ozone Ross and Zittel 7 (Martin N. Ross and Paul F. Zittel, 05/16/07,Martin N. Ross (left), Environmental Systems Directorate, leads research on the stratospheric impact of Air Force launch vehicles. He holds a Ph.D. from the University of California at Los Angeles in Earth and planetary sciences and has been with Aerospace since 1989. Paul F. Zittel (right), Remote Sensing Department, leads research on the radiative and chemical properties of rocket plumes and has conducted basic research in the areas of laser-induced chemistry, vibrational energy transfer, and cryogenic spectroscopy. He holds a Ph.D. in physical chemistry from the University of California at Berkeley and has been with Aerospace since 1976. Rockets and the Ozone Layer, http://www.aero.org/publications/crosslink/summer2000/01.html Both solid and liquid rocket-propulsion systems emit a variety of gases and particles directly into the stratosphere. A large percentage of these emissions are inert chemicals such as carbon dioxide that do not directly affect ozone levels. Emissions of other gases, such as hydrogen chloride and water vapor, though not highly reactive, indirectly affect ozone levels by participating in chemical reactions that determine the concentrations of the ozone-destroying radicals in the global stratosphere. A small percentage of rocket- engine emissions, however, are highly reactive radical compounds that immediately attack and deplete ozone in the plume wake following launch. Aerosol emissions, such as alumina particles, carbon (soot) particles, and water droplets, can also act as reactive compounds when heterogeneous chemical reactions take place on the surface of these particles. Rocket emissions have two distinct effects on ozone: short-term and long-term. Following launch, rapid chemical reactions between plume gases and particles and ambient air that has been drawn into the plume wake cause immediate changes in the composition of the local atmosphere. During this phase, which lasts for several hours, the concentrations of radicals in the plume can be thousands of times greater than the concentrations found in the undisturbed stratosphere, and the ozone loss is dramatic. Ozone Link—Generic (Climate)Rocket launches will perpetuate climate change Pete Spotts, Staff writer / October 25, 2010, Will space tourists be Earth polluters? Scientists sound a warning., http://www.csmonitor.com/Environment/2010/1025/Will-space-tourists-be-Earth-polluters-Scientists-sound-a-warning Pete Spotts, Staff writer / October 25, 2010 Scratching an expensive itch to take a pleasure trip to the doorstep of space might come with an unintended consequence: altering the climate back on Earth. A new study suggests that projected increases in so-called suborbital flights – including space tourism launches – will boost the amount of soot in the stratosphere, measurably changing climate. The soot comes from hybrid rocket motors, which burn a rubbery solid fuel, aided by a gas "oxidizer" as a stand-in for oxygen. By contrast, many liquid-fueled rockets burn oxygen and hydrogen, which produces a cleaner exhaust. According to the results, temperatures in the region around the launch site would likely cool slightly as the high-altitude soot blocked some sunlight.But the soot would spread around the globe, warming the stratosphere and touching off changes in its circulation that would bring additional warming to the poles. If demand for suborbital flights grows to levels some in the industry project by 2020, black carbon's climate effect could rival the impact from soot coming from all the world's trains, trucks, and heavy construction equipment, the researchers calculate. Directory: file -> view view -> Western Europe after wwii view -> Author study: paul fleischman view -> Qpa1 7ela study Guide view -> Arctic Oil/Gas Neg view -> November 1970 Approximately 150,000-500,000 deaths Bhola Cyclone Bangladesh view -> Grade Level: 6 Unit of Study: Caribbean glce view -> Citation: Duffield, Katy view -> Table of Contents Lesson # view -> Chinese Wind Energy Disad Download 165.07 Kb. 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