Environmental Problems Pollution Climate Change

Marine Pollution The introduction into the ocean by humans, substances that changes the physical, chemical or biological environment

Plastic Pollution Video on the Problem: One solution:::: NhiBqGU&feature=related

Fig , p. 367

Fig , p. 368 Each year 240 million gallons of used motor oil are dumped in storm drains…22x the amount spilled by Exxon Valdez

Marine Pollution Bioamplification – even small amounts of pollutants can have large effects DDT example

DDT in water ppm DDT in fish-eating birds (pelicans) 25 ppm Concentration has increased 10 million times DDT in small fish (minnows) 0.5 ppm DDT in small zooplankton 0.04 ppm DDT in large fish (needlefish) 2 ppm Stepped Art Fig , p. 371

Marine Pollution Eutrophication –Excess nutrients in water also lead to problems HABs Oxygen depletion

© 2011 Pearson Education, Inc. Determining Causes of Earth’s Climate Change Paleoclimatology Proxy data – indirect evidence using natural recorders of climate variability –Sea floor sediments –Coral deposits –Glacial ice rings –Tree rings –Pollen –Historical documents

© 2011 Pearson Education, Inc. Natural Causes of Climate Change Solar energy changes, Variations in Earth’s Orbit, Volcanic eruptions, Movement of Earth’s Plates Linked to Pleistocene Ice Age, Little Ice Age, Medieval Warm Period Recent change unprecedented –More likely result of human activity than natural causes

Global Warming: Causes “Green house effect”

Fig , p. 378

Global Warming: Causes Green house gases (chloroflourocarbons =CFCs, methane, CO 2, water vapor) Increasing CO 2 –Deforestation & burning fossil fuels

Table 16.01

Fig , p. 326 Today – CO 2 highest it has been in 10 million years

© 2011 Pearson Education, Inc. Ice Core Data

© 2011 Pearson Education, Inc. Global Warming The 8 warmest years have occurred since 1998 Earth’s surface temperature has risen 0.8 ° C (1.4 ° F) in last 140 years.

Fig , p. 380

ports/degree/how_do_we_know.jsp Series of videos from National Science Foundation

© 2011 Pearson Education, Inc. Changes in the Oceans Changes in deep-water circulation North Atlantic especially sensitive Melting glaciers Warmer surface waters

© 2011 Pearson Education, Inc. Changes in the Oceans Polar Ice Melting Arctic amplification Loss of more than 2 million square kilometers (800,000 square miles) of Arctic sea ice in last decade Loss of ice = enhanced warming due to lower albedo

Fig , p. 327 The North Pole 1996

© 2011 Pearson Education, Inc. Changes in the Oceans Polar Ice Melting Arctic ice melting affects polar bear survival. Food sources are dwindling for human Arctic dwellers. –Marine species migration

© 2011 Pearson Education, Inc. Changes in the Oceans Rising Sea Level – already occurring Main contributors: –Melting of Antarctic and Greenland ice sheets –Thermal expansion of ocean surface waters –Melting of land glaciers and ice caps –Thermal expansion of deep-ocean waters

© 2011 Pearson Education, Inc. Global Sea Level Rise

The Maldives in the Indian Ocean – 80% pop. live only 1m above sea level

© 2011 Pearson Education, Inc. Rising Sea Level Severely affect areas with gently sloping coastlines –U.S. Atlantic and Gulf Coasts Models predict rise between 0.5 and 1.4 meters (1.6 and 4.6 feet) by year 2100 Affects coastal ecosystems like corals

Fig , p. 340 Coral Bleaching Linked to Increased Temperatures

© 2011 Pearson Education, Inc. Changes in the Oceans Ocean acidity increase Some atmospheric carbon dioxide dissolves in ocean water. –Acidifies ocean Threatens calcifying organisms –Coccolithophores –Foraminifers –Sea urchins –Corals

© 2011 Pearson Education, Inc. Organisms Threatened by Increased Marine Acidity

Global Climate Change: Solutions? Alternative energy

Fig. 15-9, p. 355

Fig a, p. 355

Fig b, p. 355