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Climate Change

HOT TOPICS IN OCEANOGRAPHY. Climate Change. THE OZONE LAYER. OZONE = O 3 Predominantly in the Stratosphere Absorbs harmful ultraviolet (UV-B) radiation Chlorofluorocarbons (and other chemicals) break down ozone CFCs found in refrigerators, air conditioners and aerosol sprays

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Climate Change

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  1. HOT TOPICS IN OCEANOGRAPHY Climate Change

  2. THE OZONE LAYER OZONE = O3 Predominantly in the Stratosphere Absorbs harmful ultraviolet (UV-B) radiation Chlorofluorocarbons (and other chemicals) break down ozone CFCs found in refrigerators, air conditioners and aerosol sprays Methyl bromide (from microorganisms, pesticides and vegetation burning) a newly identified ozone destroyer Has led to a hole (reduction) in the ozone layer

  3. THE OZONE HOLE As an example of the size of the ozone hole: In 1998, the hole over Antarctica grew to up to 25 million km2 This is an area larger than North America & 3 times the size of Australia SO WHAT….? Ultraviolet radiation can penetrate deep into water (deeper than blue light) Not only can UV-B cause skin cancer in exposed large organisms It causes genetic damage in smaller organisms

  4. THE OZONE HOLE Phytoplankton and zooplankton are particularly susceptible to genetic damage Causing impaired reproduction, disability or mortality Primary productivity decreases by from 6% to 25% when exposed to elevated UV-B After exposing the reproductive cells of algae to UV-B levels equivalent to a 30% decrease in ozone After one hour photosynthesis dropped by 65%, their growth rate reduced by 17% and half failed to germinate In the Arctic – beginning of algal production overlaps with the greatest ozone depletion

  5. THE OZONE HOLE • Other studies have also shown that UV-B exposure in zooplankton can cause • Reduced reproduction • Decreased survival • Impaired larval development • Death • Depletion of phytoplankton and zooplankton would also have effects at higher tropic levels • e.g. reduced krill abundance • →reduced food for marine mammals • PLUS carcinogenic effects of UV-B on these larger animals

  6. Ozone Depletion

  7. ACID RAIN In 1852, the English chemist Robert Angus Smith coined the phrase "acid rain" He had noticed the connection between London's air pollution and the acidity of the city's rainfall Acid rain is effectively rainfall that contains SULFURIC ACID On land this has a variety of effects including the release of toxic aluminum ions → the water supply And it causes the acidification of bodies of water →The gills of fish collapse and are unable to extract oxygen →Reduces aquatic algae production

  8. ACID RAIN & DMS Dimethyl sulfide (DMS) Produced by phytoplankton (single celled plants) & Burning of fossil fuels also produces sulfates (SO2) These react with waters → sulfuric acid = ACID RAIN DMS also effects cloud density →reflects away incoming solar radiation→cooling effect BUT buffering effect of seawater reduces the effect in oceans

  9. GREENHOUSE GASES CO2 in the atmosphere is transparent to short wave radiation (e.g. solar radiation) But absorbs long-wave radiation (e.g. radiation bouncing back from the Earth’s surface) This “traps heat” Hence the “GREENHOUSE EFFECT” Other green house gases include: Water, methane, nitrous oxide, chlorofluorocarbons Without this effect the world would be -18oC (-4oF)

  10. WORLD CARBON DIOXIDE DISTRIBUTION

  11. THE ATMOSPHERIC CONCENTRATION OF CO2 HAS BEEN STEADILY INCREASING Winter Summer

  12. GREENHOUSE EFFECT Since the 1850s carbon dioxide in the atmosphere has risen 280ppm to 360ppm Models analyzing the effects of this increase predict a 1oC - 5.8oC temperature increase by 2100

  13. PREDICTED EFFECTS • More extreme weather conditions • Flooding • Changes in patterns of heat distribution • Movement of currents • Changes in wind directions • Change in plant & animal distribution • Disease outbreaks (e.g. malaria & west Nile virus) • Melting of ice caps → increase in sea level • For Virginia- hotter and more humid summers? • - more thunderstorms/tornadoes?

  14. SOURCES OF CARBON DIOXIDE IN THE US Transportation. Cars, sport-utility vehicles and other light trucks emit 20 % of the nation’s CO2 pollution. If U.S. cars were a separate country, they would be the world’s fifth largest global warming polluter, emitting more than all sources than the UK combined! Industry and Buildings. Power plants. Responsible for 36 % of U.S. CO2 emissions.

  15. GLOBAL SOURCES OF CARBON DIOXIDE Fossil fuels and forest fires: 7 billion tonnes BUT Some is ‘absorbed’ e.g. 1 billion tones → new forest growth 2 billion tones → oceans (biogenous carbonaceous sediments & the carbonate buffering system) NB: Increasing CO2 absorption in the oceans may lead to an increase in acidity – plankton, mollusks & coral effected (CaCO3)

  16. IS THERE ANY EVIDENCE FOR GLOBAL WARMING? Some areas of the world are 4.5oF or more warmer than 100 years ago The average global temperature has risen by 1oF 1990-2000 was the hottest decade on record In the past 100 years the sea level has risen 4-10 inches Extreme storms are more frequent Summer droughts / heatwaves and winter floods are more frequent

  17. “ARRGH!……..I’M MELTING !” In 2000 an iceberg the size of Rhode Island broke off the Ross (Antarctic) Ice Shelf [B-15] A few days later the iceberg started to break up A month later 3 more icebergs broke off that were 22-63 miles long! Some scientist argue that this is part of a natural cycle Most of the area where shelf broke off hasn’t risen in temperature in the past 100 year HOWEVER……..

  18. “ARRGH!……..I’M MELTING !” In February and the beginning of March 2002 the 1,255 square mile (3,250 km2) Larsen B Ice Shelf disintegrated “We were astonished to see whales, penguins and seals in the place where for thousands of years there was 250m (800’) of ice” Pedro Skvarca, Argentine Antarctic Institute This area of Antarctica had warmed by 4oF (2.2oC) since the 1950s It has been suggested that the disintegration of the ice sheet was due to an increase in the temperature of the Southern Ocean

  19. “ARRGH!……..I’M MELTING !” In the northern hemisphere…. In 2001, scientists from the National Snow and Ice Data Center stated that the amount of sea ice in the Arctic was the lowest ever seen A decrease from 6.2 million km2 to 5.2 million km2of sea ice Also arctic ice thickness has decreased by 40% between the 1950s and 1990s In 2000, a fissure appeared in the largest ice shelf in the Arctic (the Ward Hunt Ice Shelf) By 2002 the fissure had opened – 2.4 miles wide in some places

  20. “ARRGH!……..I’M MELTING !” 100 years ago the Ward Hunt Ice Shelf completely surrounded the Canadian Ellesmere Island By 1982, 90% had melted - now remainder is breaking up Canadian weather stations have recorded a 0.4oF increase in temperature every 10 years since 1967 Scientists said however : “…this ice melt and permafrost thawing is happening too fast to be due to global warming.” Ralph Cicerone, University of California

  21. EFFECTS OF ICE DECREASE ON ARCTIC MARINE SPECIES The breakup of ice has made it difficult for polar bears to travel in search for seals and mates In 2002 several polar bears were stranded in Barrow, Alaska for the summer, with no access to seals Bowhead whales, which feed at the ice edge have reduced habitats, as the amount of ice edge decreases Seals that rely on ice sheets to haul up and give birth are also loosing important habitat Temperature increases are bringing thermoregulation problems for walruses in their traditional haul out sites The southern limits for Arctic cod are further north

  22. SEA LEVEL RISE The International Panel on Climate Change predicts that the sea level will rise in the 21st Century somewhere between 29 cm (3.48”) to 88 cm (2’11”) Half of this would be from THERMAL EXPANSION (the volume of water expanding due to temperature rise) The rest due to melting ice (esp. glaciers) Although this does not sound much, it would cause major flooding in low lying coastal areas (e.g. New Orleans) Especially during storm & hurricane conditions

  23. Melting glaciers and disappearing snow cover have now been recorded on five continents. Since 1995, more than 5,400 square miles an area equal to Connecticut and Rhode Island combined have broken off of the Antarctic ice shelves & melted. If the all the polar ice melted, the sea level would rise 262’ (88m) Although this would take a temperature increase of 36oF (20oC) = 3x the worst case scenario for the 21st century

  24. FURTHER POTENTIAL OCEANOGRAPHIC EFECTS GLOBAL WARMING Added rainfall in the north Atlantic, plus freshwater from melting ice could slow down the Atlantic conveyor belt – moving water from the tropics to the cooler regions It’s assumed that the polar regions are the driving force behind the large-scale movement of seawater The Gulf Stream and North Atlantic Drift would bring less water to northern Europe – climatic conditions would become more like other areas of the same latitude (e.g. Canada) 2001 - The Intergovernmental Panel on Climate Change said that most models show that thermohaline circulation would weaken

  25.                   PREVENTING GLOBAL WARMING Energy efficiency is the cleanest, safest, most economical way to begin to curb global warming. No global warming solution will succeed unless we can control emissions from cars. Although you cannot remove CO2 from a car's exhaust, you can make them pollute less by making them more fuel efficient. By using today's best technology, car makers could dramatically increase the fuel economy of their cars and trucks. Current technology could turn the nation’s best-selling SUV (Ford Explorer) from a 19 mpg gas-guzzler to an efficient 34 mpg. Using gasoline-electric hybrid vehicles, e.g. the 70 mpg Honda Insight and 55 mpg Toyota Prius

  26. Clean up our electrical power plants. Most electric utilities still use coal to produce electricity, spewing millions of tons of carbon dioxide and other pollution into the atmosphere every year. Part of the problem could be solved by converting these plants to burn cleaner natural gas. We could do much more to save energy in our homes and office buildings. More energy efficient lighting, heating and air-conditioning could keep millions of tons of carbon dioxide out of our air each year.

  27. Step up the use of clean wind and solar energy. Harnessing the clean, abundant energy of the sun and wind is critical to solving the global warming problem. Technological advances have reduced the cost of electricity generated by the wind down by 82 % since 1981. Solar energy technology has made improved greatly- new photovoltaic cells convert even more sunlight directly into electricity. The costs of wind and solar power are becoming now competitive with dirty coal-fired plants. Renewable sources currently make up less than 1% of the energy market in the US. Kansas, Nebraska, and North and South Dakota have great potential for wind power Utah, Nevada and New Mexico have considerable solar power potential

  28. McCain-Lieberman Bill This bill proposed that industries should have a cap on how much CO2 they could emit (2000 levels) Companies would get credits for reducing emissions If a company could not reduce emissions it could compensate in other ways e.g. planting trees BUT it did nothing to control car emission HOWEVER the bill was defeated Oct 31st 2003 in the Senate “…the senate today told the American people that carbon dioxide reductions are unacceptable, and rightly so”Senator James Inhofe (R.Okla.)

  29. KYOTO CONVENTION US produces 25% of greenhouse gas emissions 1997 – 5.2% of 1990 CO2 emissions by 2012 the US has not signed 1997- The senate rejected Kyoto principals 95 to 0 US trying to claim that most of their emissions are absorbed by “sinks” eg forests 2000 – Still no agreement 2001 – Although 178 counties attended the Bush Administration refused to send delegates DESPITE Bush’s 2001 campaign pledge to control CO2

  30. OPTIONAL SECTION THE BUSH ADMINISTRATION & CLIMATE CHANGE NB – YOU WILL NOT BE TESTED ON THIS Extracts from: Robert F. Kennedy Jr. (2003) Crimes Against Nature. Rolling Stone Magazine.

  31. “The Administration has developed a comprehensive strategy on climate change that is informed by science, emphasizes innovation and technological solutions, and promotes international collaboration…” – Spencer Abraham(US Secretaryof Energy)

  32. THE BUSH ADMINISTRATION & CLIMATE CHANGE • Republican pollster Frank Luntz in a memo to memo to Republican leadership noted that: • scientific evidence is against the Republicans on issues like global warming, BUT • He advised them to find scientists willing to hoodwink the public. "You need to continue to make the lack of scientific certainty a primary issue…..by becoming even more active in recruiting experts sympathetic to your view." • He also told them to say 'Climatechange' as he said it "is less threatening than 'global warming.' While global warming has catastrophic connotations attached to it, climate change suggests a more controllable and less emotional challenge." R. Kennedy Jr, 2003

  33. In the past two years the Bush administration has altered, suppressed or attempted to discredit close to a dozen major reports on Global warming. • These include a ten-year peer-reviewed study by the International Panel on Climate Change, commissioned by George Bush Sr. in 1993. • →the Bush administration commissioned the National Academy of Sciences to find holes in the IPCC report. • HOWEVER not only did the NAS • confirm the existence of global warming and the role of green house gases played in the phenomenon BUT • it predicted that the effects of climate change would be worse than previously believed, giving an estimate that global temperatures will rise between 2.5 and 10.4 degrees by 2100. R. Kennedy Jr, 2003

  34. This was reinforced in May 2002 - report by scientists from the EPA, NASA and the NOAA, which was submitted to the United Nations by the U.S., predicted similarly catastrophic impacts. When confronted with the findings, Bush dismissed it and said: "I've read the report put out by the bureaucracy.” However the White House later stated that, in fact, he hadn't. Instead of acting on the overwhelming information so far the White House announced that further study into and assessment of the issue was required (= the Climate Research Initiative) In February, the National Academy for Sciences stated that the CRI was “a rehash of old studies and established science lacking ‘most elements of a strategic plan.’ ” R. Kennedy Jr, 2003

  35. In September 2002, the EPA annual report on air pollution was released. However the traditional update on global warming had been removed by White House staff. On June 19th, 2003, an EPA commissioned "State of the Environment" was released but information and statements about global warming had been removed by White House staff. The removed sections included the results of a report by the National Research Council. Instead was a report funded by the American Petroleum Institute criticizing scientific studies that had highlighted the dangers of global warming. In July 2003, EPA scientists leaked the results of a study that showed that John McCain’s plan to reduce the global warming gases could achieve its goal at very small cost. In May 2003, officials had acted to get the results of this study repressed. R. Kennedy Jr, 2003

  36. In a March 2003, Republican pollster Frank Luntz wrote a memo to the Republican leadership and outlined the White House strategy on energy and the environment: "The environment is probably the single issue on which Republicans in general and President Bush in particular are most vulnerable," he wrote. He added that the public views Republicans as being "in the pockets of corporate fat cats who rub their hands together and chuckle maniacally as they plot to pollute America for fun and profit." So he warned "Not only do we risk losing the swing vote, but our suburban female base could abandon us as well." THERFORE he recommended that Republicans don the sheep's clothing of environmental rhetoric WHILE DISMANTLING ENVIRONMENTAL LAWS. R. Kennedy Jr, 2003

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