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Explore the importance of the ozone layer in protecting the Earth, the causes and effects of ozone depletion, and the scientific consensus on global warming. Discover the connection between solar activity and climate change, as well as the greenhouse effect and rising CO2 levels.
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Ozone layer Airplanes, Mt. Everest UPPER ATMOSPHERE: Space Shuttle, satellites Aurora Millionth Atmosphere Meteors Thousandth Atmosphere EARTH’s ATMOSPHERE LOWER ATMOSPHERE: Sea Level 1 atm. 70°F Mile-High 83% atm. 52°F 14,000 ft 1/2 atm. 12°F Nitrogen (N2) 78% Oxygen (O2) 21% Water vapor (H2O) ~1% Carbon Dioxide (CO2) 0.035% Other gases near zero
Ozone absorbing Solar UV light is what heats up the stratosphere OZONE LAYER Without the ozone layer, all solar far-UV light would get to ground causing fast cancer and germicide killing of many things from top-to-bottom of food chain. OZONE LAYER
HOW TO GET RID OF THE OZONE 1973:Planetary Astronomer working on the atmosphere of Venus realizes that chlorine will ‘kill’ ozone, and would do so on Earth 1973:Lovelock measures CFCs, finds that all mankind’s production still in the atmosphere 1974:Rowland & Molina put together that manmade CFCs will go to stratosphere, release chlorine, and kill ozone 1974-1978:Rowland & Molina work confirmed, tested, extended; result became highly confident 1995:Rowland & Molina get Nobel Prize
OZONE ‘DEBATE’ If the ozone layer gets thinner by half over most of the Earth, then there will be massive extinctions and die-offs DuPONT put massive amounts of money into a smear campaign against Rowland & Molina
Put severe limits on CFC production Open for signature in 1987 In force in 1989 189 Nations ratified protocols Updates in 1990, 1992, 1995, 1997, 1999 UN Sec.Gen Kofi Annan: "Perhaps the single most successful international agreement to date..." MONTREAL PROTOCOLS Summary of Montreal Protocol Control Measures Ozone Depleting Substances Developed Countries Developing Countries Chlorofluorocarbons (CFCs) Phased out end of 1995 Total phase out by 2010 Halons Phased out end of 1993 Total phase out by 2010 Carbon tetrachloride Phased out end of 1995 Total phase out by 2010 Methyl chloroform Phased out end of 1995 Total phase out by 2015 HCFCs Freeze from beginning of 1996 35% reduction by 2004 65% reduction by 2010 Freeze in 2016 90% reduction by 2015 at 2015 base level Total phase out by 2020 Total phase out by 2040 HBFCs Phased out end of 1995 Phased out end of 1995 Methyl bromide Freeze in 1995 at 1991 level Freeze in 2002 at average 25% reduction by 1999 1995-1998 base level 50% reduction by 2001 20% reduction by 2005 e 70% reduction by 2000 Total phase out by 2015 Total phase out by 2005
CURRENT SITUATION DuPONT has been earning massive profits from making CFC replacements Ozone killers are now falling; Our atmosphere will have recovered in ~50 years.
2009 * GLOBAL WARMING • Global Warming is an observed fact, and everyone agrees that it is so • Completely unprecedented throughout all known history of Earth • Earth has warmed by 1.4°F in last century • It has been accelerating in the last 35 years
AURORA AURORA OCCUR IN AN ARC AROUND THE MAGNETIC POLE AURORAL ARCS ON SATURN AURORA VIEWED FROM SPACE SHUTTLE [Note Orion in background] SOLAR FLARE SPEWS OUT CHARGED PARTICLES, THESE COME TO EARTH, SPIRAL DOWN MAGNETIC FIELD LINES, MAKE ATMOSPHERE ‘FLOURESCE’ CAUSING AURORA
SOLAR FLARES SCREW UP RADIO COMMUNICATIONS FLARES INDUCE HIGH VOLTAGES IN POWER GRIDS, FRY CIRCUITS, CAUSE BLACKOUTS FLARES ‘FRY’ SATELLITE ELECTRONICS
2009 * LITTLE ICE AGE
GOOD CONNECTION BETWEEN LONG-TERM SOLAR ACTIVITY AND GLOBAL TEMPERATURES
IS GLOBAL WARMING CAUSED BY INCREASING SOLAR ACTIVITY?? • Reasonably good correlation between solar activity and world temperature from 1800’s to ~1980 • A reasonable conclusion is that the warming from 1800’s to ~1980 is dominated by rising solar activity
BUT GLOBAL WARMING SINCE ~1980 CANNOT BE DUE TO INCREASED SOLAR ACTIVITY • Global Warming is risingfast since 1980 • Solar activity has been holding steady or falling since 1980 ==> The fast-rising and unprecedented Global Warming is not due to solar activity
GREENHOUSE EFFECT Greenhouse gases: CO2, methane, nitrous oxides Transparent in optical Opaque in infrared Greenhouse effect: Atmosphere heated in optical max=0.0029/5700°=0.5microns Atmosphere cools in infrared max=0.0029/280°=10microns Gases stop surface from cooling
INCREASING CO2HOTTER EARTH CO2 concentration increased by 35% in last century Detailed calculations prove that this increase in CO2 is responsible for the observed global warming since 1970’s 100,000 year CO2 concentration Temperature Global temperature follows CO2 concentration
SCIENTISTS HAVE A UNIVERSAL CONSENSUS THAT GLOBAL WARMING IS REAL, LARGE, AND CAUSED BY HUMANS INTERNATIONAL SCIENCE ORGANIZATIONS: • World Meteorological Organization • International Astronomical Union • European Geosciences Union • International Union of Geodesy and Geophysics • World Health Organization • Intergovernmental Panel on Climate Change • Network of African Science Academies • National science academies of: US, Russia, UK, Germany, Japan, Canada, France, Brazil, Italy, India, China, Australia, New Zealand, Sweden, … AMERICAN SCIENCE ORGANIZATIONS: • American Meteorological Society • American Astronomical Society • American Geophysical Union • American Physics Society • American Association for the Advancement of Science • Geological Society of America • American Chemical Society • American Institute of Physics • American Medical Association • American Statistical Association • National Academy of Science • National Research Council
HEAT WAVE PROBLEMS • 40,000 deaths by heat wave in western Europe in 2003 • 15,000 deaths by heat wave in Russia this summer
INCREASED INTENSITY OF HURRICANES • Global warming causes the sea temperatures to rise, hurricanes get their energy from the hot ocean surface, so hotter oceans mean more intense hurricanes • The intensity of hurricanes will rise, not their frequency • Here in Louisiana, we have been living through the proof: • 1960-2004 (44 yrs) Camille (1969) Betsy (1965) • 2004-2010 (6 yrs) Katrina (2005) Rita (2005) Gustav (2008) Ike (2008)
SEA LEVEL RISING • Heating up of water (by global warming) causes water to expand, raising sea levels • (currently, this is the dominant effect) • Melting of the Greenland and Antarctic icecaps raises sea levels • (melting of floating polar sea ice does not raise sea levels) • Thermal inertia in icecaps is huge takes centuries to melt the icecaps • 21st century sea level rise is expected to be 1.5-4 feet • (disastrous for many island nations, low coastal areas, and anyone near the ocean) • If all icecaps melted (will take >1000 years), ‘only’ 250 feet sea level rise • (majority of world’s population becomes homeless)
BUT THE BIGGEST PROBLEM IS THAT THE CLIMATE WILL CHANGE, CAUSING DROUGHTS IN MANY PLACES, FLOODING IN OTHERS • Monsoon rains in Pakistan last month, all-time worst, 1400 die in floods, 13,000,000 people displaced • All Australia will become permanent severe drought, all farming & livestock raising will be lost • Sub-Sahara Africa; drought worsens and extends
EFFECTS OF GREENHOUSE GASESOVER YOUR LIFETIMES • Average temperature rise of 3°-10°F • Ocean level raises 1.5-4 feet • Droughts in some regions • Greatly increased rain in other regions FOR LOUISIANA: • Lose ~4000 sq.miles of land • Increased intensity of hurricanes • 5°-10° hotter summers
GLOBAL WARMING CONCLUSIONS • The world is heating up fast, now at a rate of 1°F per 25 years • Global warming is certainly caused by man-made greenhouse gases (mainly from burning fossil fuels and deforestation) • In your lifetimes; 4°-10°F warming, 1.5-4 feet sea level rise, high intensity hurricanes, massive droughts around world… • The science is sure and confident, but, what-to-do about these effects is a political-social question…