Unit 1.2: Earth’s Atmosphere

Period 4 APES

Introduction

This Unit ● Greenhouse effect: The greenhouse effect is a process by

which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases

● Cycling Carbon: The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth.

● Climate Zones: Are divisions of the Earth's climates into general climate zones according to average temperatures and average rainfall

● Weather Patterns and Storms ● Creating conditions suitable for life

The Structure of the Atmosphere

By: Nicholas Cochrane

Composition

The Atmosphere contains a large amount of different gasses.

Gas Mole fraction

Nitrogen (N2) 0.78

Oxygen (O2) 0.21

Water (H2O) 0.04 to < 5x10-3; 4x10-6 — strat

Argon (Ar) 0.0093

Carbon Dioxide (CO2) 370x10-6 (date: 2000)

Neon (Ne) 18.2x10-6

Ozone (O3) 0.02x10-6 to 10x10-6

Helium (He) 5.2x10-6

Methane (CH4) 1.7x10-6

Krypton (Kr) 1.1x10-6

Hydrogen (H2) 0.55x10-6

Nitrous Oxide (N2O) 0.32x10-6

Carbon Monoxide (CO)

0.03x10-6 to 0.3x10-6

Chlorofluorocarbons

3.0x10-9

Carbonyl Sulfide (COS)

0.1x10-9

Layers

http://projectedgeofspace.files.wordpress.com/2012/01/figure-05-02.jpg

Troposphere

● 8 to 16 kilometers above Earth's surface● Temperatures decrease by about 6.5°C with

each kilometer● At the top of the troposphere is the

tropopause, a layer of cold air (about -60°C) forms

Stratosphere

● 50 kilometers above the earths surface● temperatures increase with altitude● About 90 percent of the ozone in the

atmosphere is found in the stratosphere.● one percent of total atmosphere’s water

vapor● slow vertical air motion● temperatures peak at about -3°C

Mesosphere

● 85 kilometers above the earths surface● Temperatures decrease with altitude● low of about -93°C

Thermosphere

● 1,000 kilometres above the earths surface● warm with altitude, rising higher than 1700°

C.

Radiative Balance and the Natural Greenhouse Effect

Victoria Owen

Major Greenhouse Gasses Maribeth Villanueva

Natural vs. Human Made

Natural

Natural GHGs include:Water vaporOzoneCarbon dioxideMethaneNitrous oxide

Human Made

Synthetic Chemicals are emitted because of human activity. Also, humans increase some of the natural chemicals, which throws off balance.

Human Made Cont.

Hydrofluorocarbons and perfluorocarbons-AKA F gases.

Vertical Motion in the Atmosphere

Karis Heidebrecht

Weather Patterns• Many start with rising air. This could happen by:

•Convection•Winds running into mountains •Convergence - air masses running into each other and pushing upwards, causing storms.

Atmospheric Conditions

• Can be stable or unstable

• Unstable atmosphere more likely to produce clouds and storms

• Stable atmosphere more likely to produce calm weather.

Atmospheric Circulation

Dani B

Atmospheric Circulation

Cierra Bordwine

Climate, Weather and Storms

Geoffrey Ashton

The Global Carbon CycleDaniel Monsalve

The CycleThe carbon cycle is based around different stores of carbon.● CO2 in the atmosphere.● Carbonate and carbonic acid in oceans.● Organic matter on land or underwater. On average a carbon atom spends● 5 years in the atmosphere● 380 years in oceans or sediments● 10 years in terrestrial vegetation

Carbon Movements

Carbon in the atmosphere is scrubbed out by rain into oceans or sediment or absorbed into plants

Carbon can stay in fossil fuel deposits for millions of years before it eventually returns to the atmosphere.

Human ImpactHumans have disrupted the equilibrium of the natural carbon cycle.

We have released large amounts of carbon into the atmosphere from using fossil fuels like oil and coal.

Also deforestation slows the rate at which carbon is absorbed by plants.

The Global Carbon Cycle

McKenna Chase

Michaela Brost

What Are Feedbacks?

Feedbacks: Interactions between climate variables such as temperature, precipitation, and vegetation, also elements such as clouds and albedo that control the Greenhouse Effect.

Positive Feedbacks

Positive Feedbacks amplify temperature changes by strengthening the Greenhouse effect or by reducing albedo.

Positive Feedbacks Continued

Water Vapor Feedback- The presence of more water vapor as temperatures increase raises the Greenhouse Effect and the absorption of solar radiation which heats the planet.Cloud Feedback on Terrestrial Radiation- Warmer temperatures increase water vapor amounts, which can increase cloudiness and can increase the temperature even further.Ice-Albedo Feedback on Solar Radiation- Rising temperatures cause polar glaciers and floating ice sheets to recede, decreasing Earth’s albedo and raising temperatures.

Negative Feedbacks

Negative Feedbacks make the climate systems less sensitive to the factors that trigger them.

Negative Feedbacks Continued

Cloud Feedbacks on Solar Radiation- As temperature and atmospheric water vapor levels rise, cloudiness may increase. Greater cloudiness raises Earth’s albedo, reflecting more solar radiation back into space and lowering the temperature.

Vegetation Feedback on Solar Radiation- Deserts may expand as temperatures rise, which would increase Earth’s albedo and lower the temperature.

Key Terms (Katrina Moore)

● Carbon Cycle: The biogeochemical cycle in which carbon is

exchanged among the biosphere, pedosphere, geosphere,

hydrosphere, and atmosphere of the Earth.

● Greenhouse effect: A process in which thermal radiation from a

planetary surface is absorbed by atmospheric greenhouse gases

● Photosynthesis: CO2 + H

2O + light → "CH

2O" + O

2

● Respiration: "CH2O" + O

2 → CO

2 + H

2O + energy

● Climate Zones: Are divisions of the Earth's climates into general

climate zones according to average temperatures and average

rainfall

Continued● Troposphere: The lowest layer in the atmosphere; it is where weather

occurs

● Stratosphere: The second layer of the Earth’s atmosphere; the

temperature raises with altitude

● Mesosphere: The third atmospheric layer; it is the opposite to the

stratosphere in that its temperature lowers with altitude

● Thermosphere: It is the fourth layer in the atmosphere and it contains

ultraviolet radiation and ionization.

More Continued● Convergence: air masses running into each other and pushing upwards,

causing storms.

● Angular Momentum: Product= mass X velocity

● Coriolis Force: Force that is caused by Earth’s rotation

● Low Pressure Areas: Circulates counterclockwise

● High Pressure Areas: Circulates clockwise

● Weather Belts: Rings around Earth that have different qualities.

● Radiative Balance: A theory that states that the amount of colar energy

Earth receives is equal to what it gives.

● Feedbacks: Interactions between climate variables that control the

Greenhouse Effect

More More Continued

● Positive Feedbacks: Strengthen the Greenhouse Effect and/or

reduce albedo.

● Negative Feedbacks: Reduce the sensitivity in the climate system.