ENVS Midterm

What is ozone

Layer of atmosphere that blocks UV rays

Earth is what kind of system and why

Closed system, Matter moves through subsystems (no gain/loss)

Structure of atmosphere (open system)

Troposphere and Stratosphere

What does Troposphere do

Provides air we breathe & weather

What happens in stratosphere

Where chem rxns take place

Where is greenhouse effect most prominent

stratosphere

2 locations of O3 in atmosphere (good or bad)

Stratospheric ozone (good), Tropospheric ozone (bad)

Solar radiation components

43% in visible light

49% near infrared

7% UV spectrum (0.01-0.04 um)

UVB effects

* Skin cancer/sunburns
* DNA mutations (skin cancer)
* Damage to embryos (aquatic environments)
* Damage to eyes (cataracts)
* Decrease photosynthesis productivity (phytoplankton)

Breakdown of Ozone reactions

UVC → O + O → O3 + UVB → O + O2 → O2 + O2

Harm of CFCs

Single Cl atom can break down many O3 molecs

CFC Chain Reaction

UVB → CF2Cl2 → (Cl + O3 → ClO → Cl) Chain rxn

→ CF2Cl. →O2

Why Antarctica in the Spring?

1. Cold causing polar stratospheric clouds
2. chlorine in the atmosphere from CFCs
3. Sunlight, solar radiation breaks down CFCs

Anthropogenic

Pollution caused by humans

Primary pollutants

Sulfur dioxide

Nitrogen mono/di oxide

CO, CO2

Particulate Matter

Secondary Pollutants

Ground level Ozone

Sulfuric acid

Nitric acid

PM2.5

easily entered into lungs and is harmful

Point Source

Can pin point where the source is (smoke stack) (stationary)

Non point source

Mobile sources (vehicles)

Acid Deposition happens when

Sulphur dioxide and nitrogen oxide emissions transform into secondary pollutants

Acid Deposition effects

Lowers pH soil and water

Amphibians breath through skin,

Eggs in water are more vulnerable

Runoff accumulates in rivers and streams

Destroys structures

4 categories of Canada Environmental Protection Act

1. Criteria air contaminants
2. Persistent organic pollutants
3. Heavy metals
4. Toxic air pollutants

Cap and Trade policies

Upper limit for pollution set for each factory

If one produces less, they can sell part of their allotment to another factory

Can cause a lot of pollution in a small area

Main components of industrial smog

Sulphuric acid, Ammonium sulphate, Soot

Photochemical smog formula

Ground level ozone (O3) + PM2.5 + SO2 + NOx

Ground level ozone is made how

NOx + VOCs react in sunlight

Nitrogen Oxides (NOx) Causes

Cars, Transportation, Residential

PM2.5 Causes

Residential Fuel Combustion (wood burning stoves), Industry, Transportation

Sulphur Dioxode (SO2) Causes

Smelters, Industry, Cement, Transportation

Volatile Organic Compounds Causes

Solvent use, Cars, Transportation, Surface coating/printing, Res fuel combustion, Industry

Percent Earth absorbing and reflecting shortwave radiation

70% absorbed and 30% reflected

Albedo definition

Amount of solar radiation reflected by a surface

What does Earth’s surface do?

Absorbs shortwave solar radiation

Warms & emits longwave radiation

Earth’s Greenhouse Gases

Water vapour H2O

Carbon Dioxide CO2

Methane CH4

Nitrous oxide N2O

CFCs and HFCs

Tropospheric Ozone O3

Length of time needed to predict climate change

30 years

If average temp rises, what is expected to see

Rising temps

More precipitation on coast

More extreme storms

More record temps

Ice melting

Warming oceans

Sea level rise

Impacts on biodiversity

Paleoclimate

Climate of Earth’s past

Paleoclimatology

study of climate before instrumental measurements

Methods to study past climates

Air bubbles in ice cores

Tree rings

Coral skeletons

How are glacial cycles caused

Changes in distance and orientation of Earth relative to sun

Climate Forcers

Alters balance of incoming solar radiation relative to amt of heat that escapes into space

Positive: warms

Negative: Cools

Sources of Methane

Rice paddies, Cattle, Landfills, oil & gas exploitation

Nitrous Oxide N2O Sources

Agriculture fertilizers, vehicle emissions

Tropospheric ozone Sources

Increased by activities that release NOx

Positive feedback cycles are what

Self perpetuating

Negative feedback cycles are what

Self regulating

Risks of melting snow and ice

sudden floods and ice dam bursts

Stabilization Triangle

Any 8 of 15 actions (wedges) would prevent CO2 from exceeding 500ppm

Wedge examples

Conservation, Energy efficiency, sustainable energy, Replace coal, Increase nuclear power, Forests, Agriculture

Project Drawdown is what

Point in the future when levels of GHGs in atmosphere stop climbing & start to steadily decline

Top 10 solutions to climate change

1. Reduced food waste
2. Plant rich diet
3. Family planning & education
4. Refrigeration
5. Tropical forests restoration
6. Wind turbines (onshore)
7. Alternative refrigerants
8. Solar farms
9. Clean cooking 
10. Rooftop solar photovoltaics

What is climate mitigation

Efforts to help deal with existing climate change problems

Climate mitigation strategies

Lower energy demand

Renewable energies

Clean electricity

Reduce non CO2 emissions (methane)

CO2 removal (reforestation)

What is intergenerational equity

Views the human community as a partnership among all generations

What is the Life Cycle Assessment

tool used to evaluate environmental burdens of a product or service from “cradle to grave”

Based on past 50 years

LCA Uses

Compare environmental performance of products

Assist design of environmentally superior products

Analyze improvements of a product

Inform public policy for improved environmental outcomes

Basis for marketing or green labelling

LCA is good for measuring what

Emissions, depletion, toxicity, land/water use

LCA is not good for understanding what

tradeoffs of bio-ecological dimensions

Purse seine efficiency

Most efficient at catching salmon

Drift Gillnet efficiency

2nd most efficient

Trolling efficiency

Worst for environment and fuel combustion

Feed provision is what

Key driver of GHG emissions in salmon fishing

Traceability (incorrect labels)

large issue in seafood industry

What is economics

Deals with production, distribution & consumption of goods & services

What is missing from current economic system

Economy is tied to the natural environment

Sustainability

Definition of sustainability

Capable of being continued without degrading the environment

Growth Paradigm (infinite growth)

More & Bigger = better

Sever environmental consequences

Destroy the economic system

Resources are not infinite

Ecosystem goods examples

Timber, drinking water

Ecosystem services examples

Nutrient cycling, water purification

What is Ecological footprint

Measure that allows to figure out what is sustainable

Influences on ecological footprint

number of people, their affluence, technology

What are internal costs

Cost required by manufacturing or purchasing an item

What are external costs

Paid by public at large

External cost examples

Degraded health, Ecosystems, Opportunities

What are Linear economies

Resources are selected without regard for renewal

What are circular economies

Resources are selected with renewal in mind

What does ecological economics consider

Valuing all resources, using resources sustainably

Difference between 1st and 2nd industrial revolution

Technology went from adding to reducing waste

Circular economy example in carpeting

Replace specific tile instead of the whole thing

What is a triple bottom line

Business continues to grow without harming environment

What is coal made of/abundance

Formed from plant matter, most abundant FF

What are advantages of coal

Safe to ship, easy to extract, evenly distributed

what is Energy Return on Energy Investment

How much energy it takes to make different energies

Hydroelectric efficiency

Most efficient EROEI

Coal efficiency

Most efficient FF EROEI

Natural Gas Efficiency

Least efficient EROEI

What is strip mining

Remove land, mine, cover back the top

What is sub surface mining

Tunnels underground, dangerous

what is Mountain top removal

Uses explosives, most impact

What do newly exposed rocks from coal mining do

Make sulphuric acid, damages aquatic environments

What is carbon capture and storage

Process of capturing and storing CO2 before released into atmosphere

What are internal costs of coal

Equipment, labour, land, processing, transport, tax, water

What are external costs of coal

Environment impact, safety, PM, CO2, Health, drinking water, Displacement

What are advantages of fossil fuels

Inexpensive, available, High energy density

What is primary energy

Raw form, found in nature

Primary energy converts to what

Secondary energy, more readily used

What is oil

Liquid FF, originates from ancient organic materials

What is natural gas, uses, emmision

Gaseous FF, Industry / heating, less CO2 than other FF

Solar energy disadvantages

Low power density, large area needed, can’t generate at night

Future needs more of what energy and less of what energy

More solar-photovolataic (cheap), Less coal