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Global Environmental Governance James Gustave Speth and Peter M. Haas Speth and Haas: Ten of the major global environmental challenges are: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Acid rain and regional air pollution Ozone depletion Climate disruption [global climate change] Deforestation Land degradation and desertification Freshwater degradation and shortages Marine fisheries decline Toxic pollutants Loss of biological diversity Excess nitrogen Acid Rain EPA Acid Rain • Effects • • Terrestrial Leaches minerals (nutrients, metals) from soil • • • • Damages leaves of plants Aquatic Irritates gills of aquatic organisms • • Interferes with gas exchange Erodes slime layer of fishes • • Reduces resistance to pathogens Erodes shells of aquatic mollusks and arthropods • • Facilitates desertification Impedes ability of crustaceans to recalcify after molting Facilitates release of toxins bound to particles in sediments Lu et al. 2010 Lu et al. 2010 Air Pollution – Components • EPA – NAAQS for six criteria pollutants • Particulate matter • • • • • • PM2.5, PM10 Carbon monoxide (CO) Nitrogen oxides (NOx) Sulfur oxides (SOx) Ground-level ozone (O3) Lead (Pb) Piccadilly Circus, Dec. 1952 PM10 Concentrations, 2005 Red Line: US NAAQS, pre-2006 Matus et al. 2012 Air Quality (Tropospheric NO2) Summer 2006 1945 1960 1974 Bahia http://www.nybg.org/bsci/res/bahia/Defor.html 1990 Tropical Forest Loss • Four major types 1) Tropical rain forests • 2) Moist deciduous forests • 3) Usually less diverse than rain forests Dry zone forests • 4) More than 50% in Africa Tropical upland forests • • More than half in Brazil (41%) and Indonesia (13%) Includes cloud forests Current Status • Not all tropical rain forests are the same or under the same pressures Worldwide – ~66% cleared for agriculture • • • • Africa – Population growth & subsistence farming Asia – Logging; subsistence farming increasing Latin America – Ranching; subsistence farming increasing Tropical Forest Loss Region Land Area Forest 1980 Forest 1990 Area Annual Change % Loss (million ha) Africa 2236 568 527 -41 0.7% Asia 892 350 311 -39 1.2% Latin 1650 America 992 918 -74 0.8% World 1910 1756 -154 0.8% 4778 http://www.fao.org/docrep/t4450e/T4450E0k.htm Fresh Water • • Historically limiting factor in arid regions 1940-1990 • World population more than doubled • • Per capita water use doubled • • 400 m3 person-1 year-1 800 m3 person-1 year-1 Global water use increased fourfold • A. 2.3 billion 5.3 billion 2000: USA ~2000 m3 person-1 year-1 (~1450 gal day-1) Current Status • • • In 1996, world human population using estimated 54% of all accessible fresh water in rivers, lakes, aquifers Many people predict disastrous consequences for world’s fresh water supply in coming years This potential disaster may have several causes Fresh Water • Current Status 1. Distribution • • • Uneven compared to population • 75% of annual rainfall in areas containing less than one-third of global population • Amazon River carries 20% of global runoff through area containing 10 million people • Congo River carries 30% of Africa’s runoff through area containing 10% of population Uneven in space • North America contains 19,000 m3 per person per year vs. 4700 m3 per person per year in Asia • <10% of Mexico supplies >50% of annual runoff Uneven in time • India gets 90% of annual rainfall during summer monsoon season (Jun-Sep); runs off too rapidly for efficient use Fresh Water • Current Status 2. Usage patterns • • • • • • Agriculture – 69% Industry/Energy – 23% Domestic – 8% Varies among regions and with development • Africa – 88% for agriculture (irrigation) • Europe – >50% for industry • Japan – Industrial but uses lots of water to grow rice Personal use tracks standard of living • Africa – 17 m3 year-1 (12.3 gal d-1) • Asia – 31 m3 year-1 (22.4 gal d-1) • UK – 122 m3 year-1 (88.3 gal d-1) • US – 211 m3 year-1 (153 gal d-1) By 2020, water shortages likely in Ethiopia, India, Kenya, Nigeria, China (parts of China already face problems) Fresh Water • Possible Solutions • World may have enough fresh water but inadequate distribution mechanism Long pipelines and movement of icebergs have been proposed • • • Excessively expensive Technological limitations Fresh Water • Possible Solutions 1. Improved irrigation efficiency • 2. Drip irrigation reduces losses from evaporation • Cuts water use by 40-60% compared to conventional systems • Used on <1% of irrigated land worldwide but used extensively in some countries • Ex: Israel uses DI on 50% of irrigated land Municipal conservation • • Infrastructural losses can be substantial • Ex: 40-70% of water lost in transit in 15 major Mexican cities (similar rates in India) • Ex: Djakarta, Indonesia could cut water losses an estimated 20% by fixing leaky distribution pipes; would save ~12 billion gallons of water a year, enough to supply 800,000 people Higher price could encourage conservation • Ex: Bogor, Indonesia increased water prices 3-4x; average household water use dropped by 30% in less than one year Fresh Water • Possible Solutions 3. Reuse of urban wastewater • • 4. Use of treated wastewater for irrigation Today, at least half a million hectares in 15 countries are being irrigated with “gray water” More water-efficient industry • • 5. Practiced in industrialized nations. Amount of water needed to produce a ton of steel ranges from 23 to 56 m3 in China, compared to an average of less than 6 m3 in US, Japan, and Germany Desalination • • • 2010: Over 20 billion gallons of fresh water produced daily in ~15,000 facilities worldwide • Minimum cost = 0.2¢ gal-1 Current methods of desalination driven almost entirely by combustion of fossil fuels Solar powered desalination plants produced only 1.4 million gal d-1 in 2009 USA Today Stratospheric Ozone Depletion • Industrial processes release halocarbons and other gases into the atmosphere, reacting with ozone and destroying the ozone layer • • More pronounced in colder Antarctic than Arctic Reduced protection from harmful ultraviolet radiation • Ozone normally reacts with uv light but is regenerated • • O3 + uv light O2 + O In presence of HCs and other compounds that contain Cl • O3 + Cl O2 + ClO Deforestation • Less than 20% of original forest cover remains in many countries • • • • • Philippines, Madagascar Loss of CO2 uptake capacity Biomass burning Decomposition of organic material Increased erosion/nutrient loss Water Pollution – Nutrients • Nitrogen, phosphorus • Common sources 1) 2) 3) 4) • • Crop and lawn fertilizers Manure Sewage Detergents containing phosphates and nitrates Excessive nutrient loading eutrophication Effects 1) 2) 3) 4) • Plant growth can clog waterways (ecology, navigation) Plants can interfere with recreation (swimming, boating) Nighttime oxygen depletion Nitrate methemoglobinemia (blue baby syndrome) Nutrients can be difficult to control once in a system • • Recycling and regeneration Eutrophied water bodies can recover if sources are removed • Ex – Lake Washington Kiely 1997 Environmental Engineering