Unit 2: Global Climate - Vulnerability and Resilience

Earth's Atmosphere

Mixture of solids, liquids, and gases held near Earth by gravity

Energy Absorption

Atmosphere absorbs energy from the sun

Water and Chemical Recycling

Atmosphere recycles water and other chemicals

Importance of Atmosphere

Allows life on Earth, warms and protects from solar radiation

Composition of Atmosphere

Nitrogen (78%), Oxygen (21%), Argon (0.9%), Greenhouse gases

Nitrogen

Essential element for life, found in living things and amino acids

Atmospheric Pressure

Force exerted by air above a surface, decreases with height

Layers of the Atmosphere

Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere

Troposphere

Where we live, weather occurs, temperature decreases with height

Stratosphere

Contains ozone layer, stable with temperature increase

Mesosphere

Decreasing density and temperature, meteors burn up here

Thermosphere

Vacuum, absorbs energized short-wave radiation

Atmospheric Energy Balance

Energy in must be balanced by energy out, comes from Sun and Earth

Insolation

Solar energy occurring over specified area for set period of time

Radiation

Emission or transmission of energy in waves or particles

Shortwave Radiation

Insolation, main energy input, influenced by latitude and season

Longwave Radiation

Loss of energy from Earth's surface, influenced by clouds and gases

Convection

Transfer of heat by movement of gas or liquid

Conduction

Transfer of heat by contact

Albedo

Amount of light/radiation reflected by a surface

Insolation Absorption

31% reflected into space, 19% absorbed by atmospheric gases, 4% absorbed by clouds

Greenhouse Effect

Process where gases allow solar energy to pass through and trap heat

Greenhouse Gases

Water Vapor, Carbon Dioxide, Methane, CFCs

Water Vapor

50% of greenhouse effect, comes from evaporation

Carbon Dioxide

20% of greenhouse gases, released by burning fossil fuels and deforestation

Methane

Second largest contributor to global warming, comes from cattle and wetlands

CFCs

Synthetic compounds that destroy ozone and absorb longwave radiation

Feedback Loop

Positive: enhances changes, Negative: dampens changes

Variation in Solar Radiation

Milankovitch Cycles: Eccentricity, Tilt, Precession

Global Dimming

Decrease in solar radiation reaching Earth's surface, caused by volcanic activity, forest fires, and pollution

Positive Feedback Loop

Melting polar ice caps, lowering albedo, releasing methane

Negative Feedback Loop

Burning, increased evaporation, cooling effects

Climate Change

Changes in global patterns of rainfall, temperature, sea level, habitats, and extreme weather events

Enhanced Greenhouse Effect

Increase in greenhouse gases due to human activities, leading to global warming

Carbon

Building block of life, combines with other elements, part of carbon cycle

Carbon Reservoirs

Storage and release of carbon, major pools in oceans, atmosphere, biomass, and fossil fuels

Carbon Flux

Exchange of carbon between pools

Changes to Carbon Cycle

Altered by human activity, increased carbon dioxide emissions

Temperature Rise

Impacts of global warming, disappearance of arctic sea ice, heatwaves, coral reef decline, glacier melting

Guangzhou Sea Level Rise

Loss of farmland, coastal erosion, displacement of people

Carbon Gases in Atmosphere

Concentration, duration, and impact on warming

GWPs of Gases

Global Warming Potential of greenhouse gases

Nitrous Oxide

6% of US greenhouse gas emissions, long atmospheric lifetime

Nitrous Oxide Sources

Agriculture, fuel combustion, wastewater management, industrial processes

Nitrous Oxide Trends

Emissions decreased from mobile combustion, agricultural emissions remained similar

Nitrous Oxide Reduction Strategies

Improved fertilizer application, fuel consumption reduction, pollution control technologies

Atmospheric system

Includes natural greenhouse effect and energy balance

Greenhouse gases

Gases that trap outgoing long-wave radiation

Troposphere

Where most weather occurs, temperatures fall with height

Feedback loops

Result in changes to global energy balance

Global dimming

Reduction in solar radiation reaching Earth's surface due to pollution

Albedo

Measure of reflectivity of a surface

Enhanced greenhouse effect

Increase in greenhouse gases due to human activities

Carbon dioxide (CO2)

Main greenhouse gas, released from burning fossil fuels

Methane

Greenhouse gas released from livestock and thawing permafrost

Chlorofluorocarbons (CFCs)

Synthetic chemicals that destroy ozone and absorb long-wave radiation

Solar radiation

Energy from the Sun that drives weather systems and climates

Insolation

Incoming solar radiation

Radiation

Emission of electromagnetic waves

Convection

Transfer of heat by movement of gas or liquid

Conduction

Transfer of heat by contact

Positive feedback

Amplifies changes in global temperature

Negative feedback

Stabilizes changes in global temperature

Greenhouse effect

Process by which certain gases trap outgoing long-wave radiation

Global warming

Increase in Earth's average temperature due to enhanced greenhouse effect

Industrialization

Increase in greenhouse gases due to human industrial activities