Natural Science Exam 2 Part 2

What are conventional/criteria pollutants?

pollutants that are the most harmful to air quality and health

What are the 6 major conventional/criteria pollutants monitored and regulated by the CAA and why are they important/harmful?

sulfur dioxide, nitrogen oxides, carbon monoxide, ground-level ozone, lead, particulate matter. They are important because they are the pollutants that are most harmful to people and the environment

Understand and explain why the CAA was revised after its initial enactment in the 1960s, again in the 1970s.

It was revised because originally air quality regulations were only enforced at the state level and standards were not the same so air pollution persisted. In 1970 it was revised with federal standards.

What are the different sources of criteria pollutants?

stationary combustion, industry, transportation, wildfires

What are fugitive or nonpoint source pollutants?

emissions that enter the air from sources like leaking vales or dust from construction

What’s the difference between primary and secondary pollutants?

primary pollutants are harmful when released, while secondary pollutants are harmful after reactions in the air

What are photochemical oxidants and how do they contribute to air pollution?

photochemical oxidants are complex mixtures that are created from auto emissions that are transformed by sunlight. Ozone is an example, which damages eyes, lungs, and plant issues.

What are volatile organic compounds (VOCs)?

carbon-based chemicals that evaporate easily and interact with ozone to form photochemical oxidants in smog

What is the difference between PM 2.5 and PM 10?

PM10 is 10 micrometer or less, while PM 2.5 is 2.5 micrometers or less. PM2.5 is more dangerous because the particles are smaller meaning they can penetrate deeper into the lungs.

What are hazardous air pollutants (HAPs)?

toxic chemicals that cause cancer, nerve damage, hormone disruption, and fetal harm, accumulating in tissues and persisting in ecosystems

What are indoor air pollutants vs. outdoor air pollutants?

Indoor air can contain higher levels of pollutants because of poor ventilation. Some examples include cigarette smoke, dust, and mold. Outdoor air contains gases like carbon monoxide and ozone.

What are halogen gases and how do they relate to greenhouse gases (GHGs)?

Halogens can be found in refrigerants and air conditioning and are key greenhouse gases. Halogen compounds are generally toxic.

What are chlorofluorocarbons (CFCs) and how are they associated with the ozone layer?

chlorofluorocarbons were originally used in industrial products as refrigerants but were later found to deplete ozone over Antarctica.

What’s the difference between a heat inversion and heat island?

Heat inversions occur when cold air is trapped beneath a warmer layer, preventing air from mixing and allowing pollutants to accumulate.

heat islands refer to the phenomenon where the temperature in cities is warmer than the surrounding countryside due to the use of concrete and brick.

what happens when acid deposition occurs?

Acid rain

How are water resources redistributed by the water (hydrologic) cycle?

water is redistributed through precipitation (rain, snow), transpiration (water vapor released by plants) and evapotranspiration, which combines evaporation and transpiration to cycle moisture through ecosystems

How does the residence time of different water sources vary?

It depends on the volume and percent of total water. The higher both of these are, the longer the residence time is. The residence time for oceans is the highest from 3,000-30,000 years, while the residence time for living organisms is about 1 week.

What is groundwater and why do we need to protect it?

Groundwater is the largest source of liquid freshwater and is formed from precipitation filtering into soil and rock. We need to protect it because many people depend on it to drink

What is the water table?

The top of the zone of saturation that supplies most wells

What is the difference between an aquifer and a recharge zone?

Aquifers are porous, water-bearing layers of sand, gravel, and rock below the earth’s surface.

Recharge zones are areas where surface water filters into aquifers.

What is discharge in the context of water movement?

the amount of water passing a fixed point in a given time, measured in liters or cubic feet per second

What are virtual water exports?

water consumption which is exported in forms like crops from producer to consumer

What is water withdrawal and what sectors/industries have the highest water

withdrawal?

The total amount of water taken from a water body. Agriculture claims about 70% of water withdrawl and rice cultivations takes about 3 times as much as raising potatoes or wheat

What food sources use the most water?

Chocolate and beef require much more water than other meats or crops

What is subsidence?

the gradual sinking of the earth’s surface

What constitutes a drought?

an extended period of below-average precipitation that impacts ecosystems, agriculture, nd economies

What’s the difference between point and nonpoint sources of water pollution?

point sources are identifiable locations, such as factories or sewage plants, where pollutants are discharged directly into water bodies, making them easier to monitor and regulate.

non point sources are diffuse pollution sources, such as runoff from farms or urban areas, that lack specific discharge points and are harder to monitor and control.

Examples of biological pollutants like pathogens and waste.

Examples of waste include animal manure and plant residues. Examples of pathogens include bacteria, viruses and parasites

What is dissolved oxygen (DO) and how does it change with pollution?

the level of DO in water indicates its quality with 6 ppm or higher supporting game fish and lower levels favoring decomposers. oxygen levels drop downstream from pollution source, supporting only resistant organisms until water quality improves as waste is consumed.

What is the difference between oligotrophic and eutrophic bodies of water?

Oligotrophic waters have clear water and low biological productivity, while eutrophic waters are rich in organisms and nutrients.

inorganic compound impacts

metals-mercury, lead are highly toxic at low concentrations

nonmetallic salts-toxic elements that can affect water quality

acids and bases: industrial processes and coal mining acidify the water

What are the different levels of waste water treatment?

primary treatment-physically separates large solids from the waste stream with screens and settling tanks

secondary treatment-uses aerobic bacteria to break down dissolved organic compounds

tertiary treatment-removes dissolved metals and nutrients, especially nitrates and phosphates

organic chemical impacts

improper disposal of industrial wastes and pesticide runoff can accumulate in organisms and pose serious health risks

sediment impacts

harm ecosystems, fills lakes, clogs infrastructure, and impairs water quality

What is sustainability?

meeting our own needs today without compromising the ability of future generations to meet their own needs

What are the UN Sustainable Development Goals and why are they important?

The UN’s sustainable development goals aim to end poverty and hunger, promote health and education, ensure clean water and energy, and protect biodiversity globally.

What defines environmental policy?

refers to rules, practices, and laws that protect human health, natural resources, and environmental quality

Interpret the policy cycle and the different stages of policymaking.

the policy cycle is a path through which rules and developed, enacted, tested, and revised. The steps tend to be develop policy, build support, vote on rule, implement policy, evaluate impacts, propose changes, and then repeat.

explain why policy evolves gradually

because policies make little changes at a time, and improvements are made as needed.

Explain what a “Superfund Site” is and why we care about them.

A superfund site is a hazardous and polluted site that has been identified for cleanup. We care about them because they are dangerous to people and the environment.

Define the concept of regulatory capture and explain its implications.

Occurs when industry-friendly leaders head agencies, undermining their missions. They can cause public crisis like the 2008 financial collapse. Some implications of this include renewable energy research being reduced, environmental protections being weakened, and important issues being ignored.

Define and understand the role of nongovernmental organizations (NGOs).

groups not affiliated with governments—play a vital role in protecting areas of biological value by mobilizing public interest and financial support

National Environmental Policy Act (NEPA)

-establishes the Council on Environmental Quality to oversee environmental conditions

-directs federal agencies to consider environmental consequences in decision-making

-requires environmental impact statements for major federal projects affecting environmental quality

Clean Air Act (CAA)

provided the first nationally standardized rules to identify, monitor, and reduce air contaminants

Clean Water Act (CWA)

aims to make US waters “fishable and swimmable,” ensuring they are safe for consumption and recreation

Endangered species Act (ESA)

provides rules for protecting an endangered species and its habitat, ideally in order to help make recovery possible

Superfund Act (CERCLA)

funds the cleanup of abandoned toxic sites and holds polluter liable

Convection International Trade in Endangered Species (CITES)

protects endangered species by regulating international trade and requiring export permits to prevent illegal or harmful practices

Montreal Protocol

Phases out ozone-depleting substances, significantly reducing the ozone "hole" and protecting against harmful ultraviolet radiation

The UN Framework Convention on Climate Change (UNFCCC)

Framework for global climate action, enabling agreements like Kyoto (1997) and Paris (2015) to cut greenhouse gas emissions

Kyoto Protocol

committing industrialized countries and economies in transition to limit and reduce greenhouse gases (GHG) emissions in accordance with agreed individual targets

Paris Convention on climate change

aims to substantially reduce global greenhouse gas emissions to hold global temperature increase to well below 2°C above pre-industrial levels and pursue efforts to limit it to 1.5°C above pre-industrial levels

Safe Drinking Water Act (SDWA)

established to protect the quality of drinking water in the U.S. This law focuses on all waters actually or potentially designed for drinking use, whether from above ground or underground sources