ENVIRONMENTAL SCIENCE EXAM 4 CHAPTER 17

Atmosphere Good Ozone

Stratopshere

What causes the seasons?

The Earth is tilted on its axis by about 23.5 degrees, resulting in the Northern and Southern Hemispheres being tilted toward the sun for half of each year. This makes differences in temeperature and amount of daylight in areas away from the equator.

Atmosphere Bad Ozone

Troposphere

The layer of Earth's atmosphere in which we live

Troposphere

Troposphere

bottommost layer (from ground up to 11 km [7 mi]) ▫ Contains ¾ of the atmosphere's mass ▫ Air for breathing, weather ▫ The air gets colder with altitude

VOCs (volatile organic compounds)

carbon-containing chemicals ▫ Used and emitted by engines, solvents, household chemicals, and industrial processes ▫ Can react to produce secondary pollutants and a substance that can easily be evaporated at normal temperatures

Radon

causes 21,000 deaths/year in the United States ▫ A radioactive gas resulting from natural decay of rock, soil, or water that can seep into buildings ▫ New homes are being built that are radon resistant

Bacteria and fungal spores are potential ________.

causes of "sick-building syndrome"

Climate

describes patterns of atmospheric conditions (average conditions) in a location over long periods of time (years or longer).

How have we managed the problem with acid rain?

established an emissions trading program for sulfur dioxide • Economic incentives encourage polluters to invest in new technology or use other means to be cleaner ▫ SO2 emissions across the U.S. have fallen 67% ▫ Benefits outweighed costs 40:1 ▫ Sulfate loads in rainfall in the eastern United States were 51% lower in 2008-2010 than 1989-1991 ▫ Wet nitrogen deposition has also declined

Nitrogen oxides

formed when nitrogen and oxygen react at high temperatures; includes NO and NO2 ▫ From vehicles, industrial combustion, electrical utilities ▫ Contribute to smog and acid precipitation

Air pollutants

gases and particulate material added to the atmosphere ▫ Can affect climate or harm people or other organisms pollution outside ▫ Has recently decreased due to government policy and improved technologies in developed countries ▫ Developing countries and urban areas still have significant problems ▫ Greatest air pollution problem may be our emission of greenhouse gasses

Chlorofluorocarbons (CFCs)

halocarbons used as refrigerants, in fire extinguishers, in aerosol cans, etc.nonreactive so can reach the stratosphere and remain there for a century • UV radiation breaks them into chlorine and carbon atoms ▫ The chlorine atom splits ozone, destroying it ▫ One chlorine can destroy 100,000 ozone molecules

Lead

heavy metal used in gasoline and industrial metal smelting ▫ Bioaccumulates and damages the nervous system ▫ Banned in gasoline in developed countries ▫ Being banned in most developing countries

A system containing cool air that spreads outward as it descends

high-pressure system

Photochemical smog differs from industrial smog in that it ________.

is formed only in the pressence of sunlight

Temperature Inversions

layer of cool air becomes trapped beneath warm air, preventing any vertical mixing from occurring. ▫ The band of air where temperature rises with altitude is called the inversion layer, since the relationship is the inverse of normal. often occur in valleys, as nearby mountains block morning sunlight, creating cooler air in their shadow. ▫ This traps pollution near the ground.

Cold Front

occurs where a mass of cold, dry air replaces warm, moist air. being denser, tends to wedge underneath the warm air, which then rises and forms clouds and thunderstorms.

Tropospheric ozone (O3)

or called ground-level ozone , a colorless gas that poses health risks due to the instability of the O3 molecule Results from interactions of sunlight, heat, nitrogen oxides, and volatile carbon-containing chemicals Is a secondary pollutant Is a major component of smog Harm tissues and causes respiratory problems ▫ Is the pollutant that most frequently exceeds EPA standards

Primary pollutants

pollutants that come directly from a pollution source (soot and carbon monoxide)

Secondary pollutants

pollutants that form when primary pollutants interact or react with components of the atmosphere ▫ Tropospheric ozone and sulfuric acid

Ozone (tropospheric) is formed by a chemical reaction between nitrogen oxides and VOC's in the presence of sunlight. This makes ozone which type of air pollutant?

secondary pollutant

Industrial smog

smog created when industries burn coal or oil Carbon monoxide and soot are produced Sulfur reacts with water to form sulfuric acid, and nitrogen compounds also contribute

Photochemical smog

smog produced when sunlight drives a series of reactions involving primary pollutants ▫ Produces over 100 different chemicals ▫ Tropospheric ozone is often the most abundant ▫ NO2 causes photochemical smog to form a brown haze • Exhaust from morning traffic releases nitric oxide (NO) and VOCs into the air ▫ Photochemical smog typically peaks in the afternoon ▫ Can cause eye, nose, and throat irritation

Weather

specifies atmospheric conditions in a location over short time periods (weeks or shorter).

Residence time

the time a pollutant stays in the atmosphere • Pollutants with brief residence times exert localized impacts over short time periods ▫ Particulate matter, automobile exhaust • Pollutants with long residence times exert regional or global impacts ▫ Pollutants causing climate change or ozone depletion

Reversal of normal vertical temperature distribution in the lower region of the atmosphere

thermal inversion

Weather patterns are largely determined in the ________.

troposphere

Warm Front

occur where warm, moist air replaces cool, dry air. ▫ Some of the warm air rises and releases precipitation as it cools and condenses.

Stratosphere

11-50 km (7-31 mi) above sea level ▫ Drier and less dense, with little vertical mixing ▫ Becomes warmer with altitude (ozone absorbs sunlight) ▫ Contains UV radiation-blocking ozone layer, 17-30 km (10-19 mi) above sea level

What are primary constituents of earth's atmosphere?

78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide

What makes acid rain?

Acid deposition originates from sulfur dioxide and nitrogen oxides mostly from automobiles, electric utilities, industrial facilities • These compounds react with water, oxygen, and oxidants to form sulfuric and nitric acids

Convective Circulation

Increased evaporation causes air near the Earth's surface to be warmer and moister, creating a process. Warm air, being less dense, rises and creates vertical currents. As air rises, it cools, causing moisture to condense and fall down as rain. The cooler, denser air sinks, and the cycle repeats.

Solar Energy and its differing effects on the planet

Sunlight is most intense when it meets the planet's surface at a perpendicular angle. ▫ This minimizes the amount of atmosphere the sunlight must pass through before reaching the surface. ▫ As a result, solar radiation tends to be the most intense near the equator, and weakest near the poles.

Smog

an unhealthy mixture of air pollutants over urban areas

Residence time is the ________.

average length of time a molecule of a substance spends in the environment

Sulfur Dioxide

colorless gas with a strong odor ▫ From coal emissions from electricity generation, industry ▫ Can form acid precipitation

Carbon Monoxide (CO)

colorless, odorless gas ▫ Produced primarily by incomplete combustion of fuel ▫ From vehicles and engines, industry, waste combustion, residential wood burning ▫ Poses risk to humans and animals, even in small concentrations ▫ Binds to hemoglobin in red blood cells, preventing oxygen transport in the blood

Fungi Spores

mold, mildew, airborne bacteria cause allergies, asthma, other respiratory ailments, and diseases

What gas comprises the largest portion of Earth's atmosphere?

nitrogen

Indoor air pollutants- what contributes to indoor air issues? Most common indoor air pollutants (radon and cigarette smoke)

pollution in workplaces, schools, and homes ▫ Health effects are greater than from outdoor pollution • The average U.S. citizen spends 90% of the time indoors ▫ Exposure to synthetic materials that have not been comprehensively tested • Being environmentally prudent can make it worse ▫ To reduce heat loss and improve efficiency, ventilation systems were sealed off ▫ New buildings were constructed with windows that do not open, trapping pollutants inside Cigarettes ▫ Cause eye, nose, and throat irritation ▫ Greatly increase risk of lung cancer ▫ Contain over 4000 chemical compounds • Secondhand smoke causes similar problems to smoking ▫ While smoking has declined in developed nations, it still causes 160,000 cases of lung cancer per year in the United States

Acid rain

precipitation (rain, snow, sleet, hail) containing acid