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Global Issues

Global Issues. Global Issues. Loss of biodiversity Loss of habitat Climate change Stratospheric ozone loss. The Loss of Biodiversity. There have been 5 great extinction periods in geologic history, with the most recent occurring 65 million years ago

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Global Issues

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  1. Global Issues

  2. Global Issues • Loss of biodiversity • Loss of habitat • Climate change • Stratospheric ozone loss

  3. The Loss of Biodiversity • There have been 5 great extinction periods in geologic history, with the most recent occurring 65 million years ago • These periods are loosely defined as times when more than half of all species become extinct • After each extinction, it took upwards of 10 million years for species richness to recover • Even with a return to biodiversity, once a particular species is extinct it is gone forever

  4. The Loss of Biodiversity • The current rate of extinction is exceptional - 100 to 1000 times greater than normal • On average, a distinct plant or animal species becomes extinct every 20 minutes, and may be as high as 130 species extinctions per day • More than 11,000 plant and animal species, including 24% of all mammals, are in immediate danger of extinction due to human activities

  5. The 6th Great Extinction • The current extinction rate is comparable to the five previous great extinctions and is referred to as the 6th Great Extinction • The five causes of this enormous loss of diversity are all linked to human activities • Habitat destruction, Invasive species, Pollution, Population growth (human), and Over consumption (HIPPO)

  6. The 6th Great Extinction • 282 species in Hawaii are endangered, more than 1/3 of all the endangered species in the United States • Of those, 95% are threatened by invasive species • Indigenous amphibians worldwide have been declining by an average of 2% per year since 1960 • If nothing changes in current trends, it is estimated that 20% of all plant and animal species will be extinct by 2030, and 50% will be extinct by 2100

  7. Endangered Species Act (ESA) • Provides guidelines to protect habitat (H), regulate pollution (P), and reduce or eliminate invasive species (I) and the harvesting and consumption (O) of the identified endangered species • As of 2002, less than 10% of the species placed on the endangered list are improving; 40% are still declining and 50% are stable or unknown • Critics have attempted to drastically cut its provisions • Since the passage of the ESA in 1973, only 9 species have become extinct in the US • It is estimated that without the ESA, more than 100 US species would now be extinct

  8. Biodiversity • The loss of biodiversity in ecosystems ranging from marine coral reefs to terrestrial forests can increase the transmission of infectious diseases in humans, other animals and plants, according to a new scientific analysis in the journal Nature (2010). • This connection between two developing crises – emerging novel diseases and unprecedented declines in biodiversity – has long been suspected, but has been difficult to quantify, scientists say. • In theory, the loss of biodiversity could increase or decrease transmission of disease, said Anna Jolles, a disease ecology specialist in the College of Veterinary Medicine at Oregon State University and one of the authors of the study. • Certainly, having naturally high biodiversity should increase the potential pool of sources for new pathogens. But the evidence suggests that in most cases, biodiversity loss actually ramps up transmission of disease. • The study notes that global biodiversity continues to shrink at an alarming pace, with extinction rates estimated at 100 to 1,000 times higher than have occurred throughout most of history. • And extinctions are projected to rise dramatically in the next 50 years. If there is one message we hope comes out with this paper, Jolles said, it is the clear need to conserve biodiversity to the greatest extent possible – because it may be our best insurance policy against infectious diseases.

  9. The Loss of Biodiversity: Fish • More than 25% of the world’s fish stocks are over-harvested • The number of Atlantic cod caught off the east coast of Newfoundland was more than 800,000 tons per year in the 1960s • The population of Atlantic cod crashed in the 1990’s, and even with fishing bans, the population has not recovered • In some areas off the coast, the species has completely disappeared

  10. The Loss of Habitat: Forests • The worldwide forest loss is significant • 60% of temperate hardwood & mixed forest • 30% of conifer forests • 45% of tropical rainforest • 70% of tropical dry forests • Just 1% to 10% of the native forests stand in countries like the UK, Finland, India, China, Sweden, Vietnam, New Zealand, Costa Rica, Mexico, Guatemala, Bangladesh, Argentina, Burma, and others • The US has only 5% of native forests left

  11. Canadian Boreal Forest • The thick layers of moss, soil and peat are the world's largest terrestrial storehouse of organic carbon and play an enormous role in regulating the Earth's climate. • Wetlands filter millions of gallons of water each day that fill our northern rivers, lakes, and streams. • Supports a natural web of large carnivores, such as bears, wolves and lynx along with thousands of other species of plants and animals. • Approximately 30% of North American birds, including common backyard songbirds such as the warbler, raise their young each spring in Canada's boreal forest.

  12. Boreal Forest Loss • Every year over 1.5 million acres of Boreal Forest is cleared by logging, 90% of which is removed by clear-cutting • Logging in Canada causes almost 5 acres of forest loss every minute • The United States is the destination for approximately 80% of Canada's forest products, including lumber, toilet paper, catalogue paper and newsprint -- much of which comes from clear-cutting in the boreal forest.

  13. Global Climate Change • There were 928 scientific papers published between 1993 and 2003 with the term ‘global climate change’ in their abstracts • None of these papers refuted the claim that human activities are affecting the Earth’s climate • In the same time period, over 3,500 “hard news” articles were written about global climate change in the LA Times, Wall Street Journal, Washington Post and NY Times • Approximately 53% of these articles cast doubt on the link between human activities and Earth climate change • Each year, humans add 6 to 8 billion tons of carbon to the atmosphere

  14. GLOBAL WARMING Slides from Dr. Mark Hixon Professor of Zoology Oregon State University

  15. GLOBAL WARMING What are the scientific facts? "Facts do not cease to exist because they are ignored." Aldous Huxley (1894 – 1963) author of "Brave New World"

  16. GLOBAL WARMING Rate of burning fossil fuels is increasing exponentially …  U.S.A. =~ 5% of world population & produces ~ 25% of global emissions

  17. GLOBAL WARMING … so atmospheric carbon dioxide is increasing exponentially. data from Hawai’i observatory: (note seasonal “breathing” of Northern Hemisphere: fall-winter: Photosynthesis < Respiration: CO2 increases spring-summer: P > R: CO2 decreases) >40% increase in CO2 since start of Industrial Revolution

  18. GLOBAL WARMING Excess carbon dioxide is warming the atmosphere. 0.76°C (1.37°F) increase globally since 1860 (*1961-1990) additional 0.6°C increase even if all emissions ended today Sources: National Center for Atmospheric Research 2008 & IPCC 2007

  19. GLOBAL WARMING Ice core data show temperature increases with carbon dioxide levels. Greenland ice core: data from air bubbles in polar icecap cores temperature derived from oxygen-18 / oxygen-16 ratio

  20. GLOBAL WARMING glaciers are melting worldwide: North America South Cascade Glacier, near North Cascades National Park, Washington

  21. GLOBAL WARMING glaciers are melting worldwide: North America

  22. Glacier Retreat • These two images show Portage Glacier, near Anchorage, AK, in 1914 and 2004 • Alaska’s glaciers are receding at twice the rate previously thought

  23. 1985 2002 Greenland ice cap is melting more rapidly than predicted: if completely melted, sea level will rise >20 feet, but this should not happen for at least a century

  24. GLOBAL WARMING south polar ice is also melting • less krill  less fish  less penguin food • altered ice  longer penguin foraging trips  chicks starve •  penguin populations are declining • Breeding pairs of emperor penguins at one colony: 1952-1999:

  25. 2011 Data • A study published in the journal Science reports that the current level of carbon dioxide (CO2) in the atmosphere – about 392 parts per million – is higher today than at any time in measurable history -- at least the last 2.1 million years. Previous peaks of CO2 were never more than 300 ppm over the past 800,000 years, and the concentration is rising by around 2 ppm each year. • The Arctic summer could be ice-free by mid-century, not at the end of the century as previously expected, according to a study by the National Oceanic and Atmospheric Administration

  26. 2011 NRDC Report • In the coming decades, Miami, New Orleans and Norfolk, Virginia are expected to be the coastal cities hardest hit by flooding and storm surges due to rising sea levels. • In Boston, where the city's airport is flanked by water, historic landmarks and critical transportation infrastructure are at a greater risk of flooding due to rising sea levels. • Los Angeles, Seattle and San Francisco will face similar danger from rising waters, according to the report. • NRDC said climate change was making heat waves, floods and droughts more severe. The Midwest was predicted to experience frequent and intense storms. Chicago, for example, could see the frequency of heavy rainfall rise by 50 percent in the next 30 years.

  27. Virginia • Norfolk was built on filled-in marsh, which is settling and compacting. • In addition, the city is in an area where significant natural sinking of land is occurring. • The result is that Norfolk has experienced the highest relative increase in sea level on the East Coast — 14.5 inches since 1930, according to readings by the Sewells Point naval station here.

  28. California • In the San Francisco Bay Area, where the threat is more acute because of a history of filling in and developing the bay, planners are thinking about elevating the Embarcadero seawall and raising the height of levees around the San Francisco and Oakland airports. • A proposed development on Treasure Island would raise the elevation of the ground to place homes farther above sea level. • In Hayward, southeast of Oakland, rising sea levels are expected to overtake marshes along its 4-mile coastline and threaten its water treatment plant and industrial district within the next generation or two. • Planners are searching for ways — and funds — to build up those wetlands as a buffer. • The city of Ventura broke ground last year on a "managed retreat" project designed to protect Surfers Point, a popular beach and surf spot, by moving a bike path and parking lot some 65 feet from the shore

  29. California • In Newport Beach, the attitude change came in response to concerns about the future of its harbor, an expansive waterfront dotted with islands and sheltered from the open ocean by the densely populated Balboa Peninsula. • Tens of thousands of people live in the area, much of it just a few feet above sea level. • After a sea level rise of just over a foot, a 2008 city-commissioned study said, an extreme high tide would result in widespread flooding on Balboa Peninsula and "near-complete flooding of Balboa Island."

  30. Effects of Climate Change • In February 2009, the National Audubon Society released a report about climate change’s effects on North American birds • Audubon announced that some 177 species of North American birds have shifted their range northward over the last 40 years • During the same period, the average January temperatures rose by 5 degrees Fahrenheit across the North American continent

  31. Effects of Climate Change • Trees in old-growth forests across the Western United States aren’t living as long because of higher temperatures and drought stress, according to a new study out of Oregon State University. • “When trees across the West appear to be dying at twice the rate they used to, that’s not a good sign,” said Mark E. Harmon, a professor of forest ecology at OSU, and one of the authors of the paper. “The doubling of the mortality rate, if it’s really widespread, that implies the lifespan could be halved.” • The increase in tree mortality has occurred over the past 50 years • During that same period, the temperature has increased by about 1 degree in the West, Harmon said. • From January 23, 2009 Gazette Times

  32. Effects of Climate Change • Islands are sinking and evacuations will occur • The residents of Tuvalu - a tiny island country in the Pacific Ocean midway between Hawaii and Australia - will abandon their homeland • Australia and New Zealand have been asked to accept Tuvalu’s 11,000 citizens, but there is no agreement yet • A total of 8 million Pacific Islanders may be forced to evacuate in the coming years • The Intergovernmental Panel on Climate Change projects a rise of up to 1 meter during this century due to polar ice melts and the thermal expansion of oceans • Increased polar ice melts may change the pattern of the Gulf Stream, causing temperatures in Western Europe to fall significantly

  33. Penguins • The Antarctic Peninsula is an 800-mile finger of land that pokes upward toward South America. • In this corner of Antarctica, the land, the sea, and the creatures that inhabit them are all in flux as a result of some of the most rapid warming on Earth. • Average winter temperatures have risen nearly 9 degrees Fahrenheit (5 degrees Celsius) in the past half century. • The Adelie penguin colony has dwindled from 320 breeding pairs to 54 between 1990 and 2004. • Not only have average winter temperatures here increased, but sea ice has retreated by a fifth since the mid-1970s, depriving the penguins of an important feeding platform from which they hunt krill.

  34. Polar Bears • Since the mid-1980s, the ratio of body mass to length among polar bears in southern Hudson Bay has dropped about 15%. The bears are getting skinnier. • Several decades ago in western Hudson Bay, triplet polar bear cubs were common. Now they're virtually nonexistent. • Once, up to 40% of the cubs were weaned by 18 months, finding food for themselves. Today fewer than 5 percent of them are. • One bear researcher is convinced that the regression of sea ice is the culprit. • And he fears that Hudson Bay's several thousand polar bears—part of an estimated worldwide population of 25,000—will vanish if, as climatologists have forecast, sea ice disappears from the bay by 2070.

  35. Other Signs • A study of 35 non-migratory butterfly species in Europe found that in recent decades about two-thirds have expanded their ranges northward by 20 to 150 miles (30 to 240 kilometers). • Many plants in Europe flower about a week earlier than they did 50 years ago and shed their leaves in the fall five days later. • British birds breed an average of nine days earlier than in the mid-20th century, and frogs mate up to seven weeks sooner. • Tree swallows in North America migrate north in spring 12 days earlier than they did a quarter century ago. • Red foxes in Canada are shifting their ranges hundreds of miles toward the Pole, moving into the territories of Arctic foxes. • Alpine plants are edging uphill and beginning to overrun rare species near mountain summits.

  36. How Bad Are Bananas?Diet Impacts on CO2 Emissions

  37. Stratospheric Ozone Loss • Ozone is found close to the earth’s surface (troposphere) and in the stratosphere • Tropospheric ozone is “bad” • A greenhouse gas, a major contributor to smog, and causes negative health effects (e.g., respiratory) • Ozone in the stratosphere is “good” • Provides a protective layer that shields the planet from harmful UV rays • Lost primarily due to human emissions of chlorofluorocarbons (CFCs,) once widely used as refrigerants, propellants and cleaning solvents

  38. Effects of Stratospheric Ozone Loss • Decreased stratospheric ozone leads to increased UV levels at the earth’s surface, which leads to increased tropospheric ozone • The world-wide reduction in frog and toad populations may be caused in part by a reduction in stratospheric ozone. A study in Oregon indicated that elevated levels of UV-B reduced the fraction of eggs that hatched. • Plankton are particularly susceptible to effects of UV light, and are vitally important to marine food webs • Cyanobacteria are sensitive to UV light and they would be harmed by its increase • A number of economically important species of plants, such as rice, depend on cyanobacteria residing on their roots for the retention of nitrogen • Humans are at risk from various cancers and cataracts

  39. Stratospheric Ozone Loss • The ozone hole over Antarctica was first officially recognized by scientists in 1985 • Over the last decade the ozone level has declined by about 3% per year on a global scale • The decline typically occurs during the Antarctic spring, from September to early December • Scientists predict that full implementation of the 1987 Montreal Protocol, which bans CFCs and other ozone-depleting chemicals, should allow the ozone layer to recover by 2060 (73 years).

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