Environmental Issues - Chapter 18 - Riverside City Collegewebsites.rcc.edu/estrada/files/2016/09/Student... · 2016-11-27 · Environmental Issues Chapter 18 ... Global Warming and

Environmental Issues

Chapter 18

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

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Environmental Issues

u Environmental health: the area of health concerns that focuses on the interactions of humans with all aspects of their environment

u Diseases associated with contaminated water, food, waste, and other pollutants

u Pollutants that result from human and industrial activities and that cause chronic diseases and global environmental damage

u Climate change, the depletion of resources, and world overpopulation


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Water and Water Quality

u Water cycle: natural process by which the earth’s supply of water is continuously collected, purified, and distributed

u Surface water: precipitation stored in lakes, reservoirs, and wetlands on the surface of the earth

u Groundwater: precipitation that sinks into the ground and makes up 95% of the world’s supply of freshwater

u Deep aquifers: giant underground reservoirs


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Water Supplies and Shortages

u In U.S. and Canada water supplies abundant but much of it is contaminated

u Withdrawal rates of surface water projected to double in the next 20 years

u Conflicts between regions and states over water supplies

u Main cause of water waste is artificially low cost of water

u Government subsidies to agriculture and industry lead to limited financial incentive to invest in water-saving technologies


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Water Supplies and Shortages

u Consumers and businesses need to use water-saving technologies

u Farmers and the agricultural industry need to develop ways to irrigate crops more efficiently

u Government and policy makers must manage water basins and groundwater fairly and effectively

u Failure to address our water-related problems will lead to economic and health problems, increased environmental degradation, and loss of biodiversity


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Virtual Water

u Virtual water: water used to produce foods, consumer products, and other services

u One hamburger = 640 gallons of water

u The amount of water needed to produce a give amount of a product is its water footprint


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Water Footprint for Food Production


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Water Pollution

u Any chemical, biological, or physical change in water quality that harms living organisms or makes water unsuitable for desired use

u Most surface-water reservoirs are contaminated by pollutants at specific locations through sewers, pipes, or ditches

u Main sources of groundwater contamination:

u Storage lagoons

u Septic tanks

u Landfills and hazardous waste dumps

u Underground storage tanks filled with gasoline, oil, solvents, and hazardous waste


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Safe Drinking Wateru The Safe Drinking Water Act (1974) established many

health standards for drinking water

u 98% of Americans have plumbing where lead can leach into tap water as pipes and fixtures deteriorate over time

u Cold water from the tap is less likely to contain lead from supply pipes

u Run water after being away to flush out potential contamination

u Many benefits to water fluoridation, but excessive fluoride consumption can lead to fluorosis


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Conserving Water

u Americans use three times the water per capita of the average worldwide

u 70% used for washing and carrying away waste

u There are many ways to use less water:

u Bathroom: shorter showers, turn off faucet when brushing teeth; low-flow toilet; water-saving showerheads

u Laundry: wash only when full load; buy only Energy Star appliances

u Kitchen: run dishwasher only with full load; do not run water continuously when doing dishes by hand


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Earth’s Atmosphere

u Troposphere: lower atmosphere, containing about 80% of the earth’s air

u Stratosphere: upper atmosphere, 11 to 30 miles above the earth’s surface

u Greenhouse effect: warming of the earth’s surface by heat trapped by gases in the lower atmosphere

u Greenhouse gases: carbon dioxide, water vapor

u Ozone in the upper atmosphere shields us from about 95% of the sun’s UV rays

u Protective in upper atmosphere, but at ground level it is a main source of air pollution


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Air Pollution

u Air pollution: the presence of one or more chemicals in the atmosphere in sufficient quality and quantity to cause harm to life

u Air Quality Index (AQI): measure of air pollution issued daily by the EPA

• 100 or higher, air is considered unhealthy for sensitive groups, such as people with asthma

• 300 or higher, air is considered hazardous

u The EPA charts four pollutants: ozone, particle pollution, carbon monoxide, and sulfur dioxide


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Air Quality Index

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Ozone and Particulate Matter

u Ozone is poisonous to most living organisms

u Ground-level ozone causes respiratory irritation, aggravates respiratory and heart disease, and damages the lungs, especially in those with respiratory problems

u Particulate matter consists of particles or droplets of dust, soot, oil, metals, or other compounds suspended in the air

u Small particles may remain in the lungs and irritate and damage alveoli; and may also trigger an immune system response that contributes to heart disease and lung disease


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Smog

u Smog: mixture of pollutants in the lower atmosphere that makes the air hazy

u Industrial smog: air pollution that forms mostly in cold weather

u Coal and oil burning

u Photochemical smog: sits as a thick haze over cities in the summer

u Vehicle exhaust, industry, and other sources combine, producing large amounts of ozone and more than 100 other chemicals

u Fossil fuels: oil, coal, natural gas

u Problems amplified by temperature inversion


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Acid Deposition and Precipitationu Acid deposition: the depositing of acidic pollutants from the

atmosphere on the earth’s surface, in either dry or wet form

u Acid precipitation: mixing of acidic pollutants in the atmosphere with moisture and their precipitation in the form of rain, snow, sleet, hail, or fog

u Environmental damage depends on the ability of the soil to neutralize acid

• Less damage where soils are alkaline—Midwest

• Extensive damage where soils are neutral or acidic—northwestern U.S., northeastern North America


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Reducing Outdoor Air Pollution

u Clean Air Act (1990) empowered the EPA to set emission standards

u Improved air quality

u Clear Skies Initiative (2002) set mandatory caps to reduce emissions of sulfur dioxide, nitrogen oxide, and mercury

u A new car today emits 75% less pollution than cars built in 1970

u 57% of Americans still live in areas where the air is considered unhealthy at some time of the year


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Global Warming and Climate Change

u Climate change is the long-term changes in average daily weather that occurs over many years

u Substantial evidence of earth’s warming; debate over whether it’s natural or human-caused

u Human activities have increased the amount of greenhouse gases in our atmosphere

u As a result, global temperatures have risen

u Melting glaciers and polar ice caps; rising sea levels

u Intensification of greenhouse effect has led to global warming


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The Greenhouse Effect

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Greenhouse Gases from Food


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What Needs to Be Done?

u Kyoto Protocol (1997), not ratified by Congress

u 2009 Copenhagen Accord: produced a nonbinding pledge to reduce greenhouse gas emissions

u 2013 world’s top scientist endorsed a cap on greenhouse gases

u Scientists now worried about feedback loops and that delaying prevention efforts could be devastating

u Substantial reductions will require massive changes in industrial processes, transportation, energy sources, and personal lifestyles


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Predicted Effects of Climate Change


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Your Carbon Footprintu Every time you use fossil fuels you

contribute to carbon dioxide emissions

u Driving a car, turning on a light, running a dishwasher

u The more CO2 you generate, the larger your carbon footprint

www.nature.org/greenliving/carboncalculator/index.htm

www.epa.gov/climatechange/ghemissions/ind_calculator.html

u Walk more; drive less

u Consume less electricity

u Recycle

u Eat less or no meat


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Indoor Air Pollutionu Indoor air pollution can be higher and more hazardous than

outdoor air pollution; yet we spend 80–90% of our time indoors

u Eleven of the most common air pollutants are usually 2 to 5 times higher inside the home

• Environmental tobacco smoke, formaldehyde, radon, carbon monoxide, mold, polybrominated diphenyl ethers (PBDEs)

• Also dust mites, animal dander, mildew

u Reduce many pollutants by keeping the house, pets, and bedding clean; maintaining 30–50% humidity; and removing shoes


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Solid Waste

u Any unwanted or discarded material that is not a liquid or gas; garbage

u 1,600 pounds per person per year in U.S.

u E-waste is the fastest growing problem; the U.S. sends most to Afghanistan and Haiti for disposal and recycling


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Hazardous Waste

u Any discarded solid or liquid material that meets one or more of four criteria:

u Contains a toxic, carcinogenic, or mutagenic compound at levels that exceed EPA standards

u Catches fire easily

u Can explode or release toxic fumes

u Corrodes metal containers

u Direct exposure poses health hazards

u Federal laws restrict the storage of hazardous waste in sanitary landfills


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Hazardous Waste

u Common forms:

u Household hazardous waste: batteries, paints, household cleaners, oils, pesticides

u Emergent contaminants: pharmaceuticals, cosmetics, antibacterial soap, shampoo, shaving cream, dishwashing liquids, plastic, flame retardants, and other chemical compounds

u Medical waste: any solid or liquid waste that is generated in the medical diagnosis, treatment, or immunization of human beings or animals

u Radiation and radioactive waste: low-level radiation used in medical and dental procedures; high-level radioactive waste from nuclear weapons and power plants


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Approaches to Waste Management

• Sanitary landfills are carefully selected sites where waste is buried in plastic-lined pits

• Incinerators burn waste and sometimes sell the energy generated by the burning

• “Not in my backyard”

• Living near a hazardous waste dump increases risk for respiratory disorders and cancer

• Recycling: circle, or loop, program; materials collected, sorted, cleaned, and processed into raw materials to make new products

• Many communities provide curbside pickup; and many states have deposit/refund programs

• Individuals can also buy recyclable, reusable, or compostable materials

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Recycling Plastic


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Ecosystems and Biodiversity

u Ecosystem: an interconnected community of organisms living together as a balanced, mutually supportive system

u Biodiversity: variety of different animal and plant species on earth and the genetic variation in their gene pools

u Human activities significantly disrupt these ecosystems and have caused a decline in biodiversity through:

u Deforestation

u Desertification

u Loss of freshwater resources


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Protecting Ecosystems

u Stringent federal and state protection of animal and plant habitats in forest, deserts, and wetlands is a component of sustainable land management programs

u Protecting endangered species; controlling climate change

u Individuals can help:

u Reusing and recycling paper products

u Refusing the buy products or materials made from endangered or threatened species

u Purchasing wood with the Good Wood Seal

u Stopping junk mail


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Energy Resources

u World energy consumption continues to rise

u World’s largest consumers:

1. China

2. United States

3. India

u Nonrenewable energy provides 93% of the commercial energy used in the U.S.


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Energy Resourcesu Crude oil: U.S. reserves will be depleted

by 2100

u Coal: largest domestic source for heat and electricity; dirtiest of all fossil fuels

u Natural gas: a mixture of gases, mostly methane; costly to extract

u Could meet U.S. energy demands for about 82 to 118 years

u Fracking: environmental and health costs unknown

u Nuclear power: problems with storing nuclear waste, and concerns about safety

u Three Mile Island (1979); Chernobyl (1986); Fukushima (2011)


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Solar Energy, Liquid Biofuels, and Energy Conservationu Solar energy: could meet 25% of consumer demand by 2050

u Wind, geothermal, and hydro power also being explored

u Biofuels—biodiesel and bioethanol—made from plants and other biological material

u Problems include increased forest clearing and soil erosion, use of water, loss of biodiversity

u Environmentalists believe the solution is to conserve

u Reduce ecological effects, diminish energy waste; shift to renewable, nonpolluting energy sources


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Your Electronic Footprint


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Population Growth

u How many people can the planet support?

u Global carrying capacity is estimated at 50 billion people

u Cultural carrying capacity—the number the earth can support at an optimum standard of living—is much less

u As it stands today, there are probably not enough resources to extend an optimum standard of living to everyone on planet right now

u Currently about 1.4 billion people are living in extreme poverty


36

Approaches to Population Control and Management

u Family planning: informed decisions about the number and spacing of children

u Programs provide information on birth control, birth spacing, breastfeeding, and prenatal care

u Could have a significant effect if implemented in developing countries

u Smart growth: concentrates growth in compact urban centers and environmentally sustainable communities


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A Sustainable Planet

u An ecological footprint compares human consumption of resources with the planet’s capacity to regenerate them

u Can reveal how sustainable a particular lifestyle is

u Can point out inequities of resource use and consumption

u The ecological footprint of the United States is the largest in the world

u Consume more resources, generate more pollution, and discard more waste

u Each of us can take actions today to reduce that footprint


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Environmental Issues - Chapter 18 - Riverside City Collegewebsites.rcc.edu/estrada/files/2016/09/Student... · 2016-11-27 · Environmental Issues Chapter 18 ... Global Warming and