Atmospheric systems

atmosphere

 dynamic system that has undergone changes throughout geological time

atmosphere contains

nitrogen (79%), oxygen (20%), carbon dioxide (0.04%), argon (0.9%), water vapour (1-4%) and other trace gases

inputs

* Light (short wave radiation) & heat (long wave radiation) from the Sun
* Heat (long wave radiation) from the Earth
* Pollutants (particle & heat)
* Gases from hydro/biosphere
* Particulates (soil, pollen etc

outputs

* Heat (long wave radiation) into space
* Heat into Earth’s surface
* Reflected light
* Precipitation
* Gases to biosphere

stores

• Gases: N2, O2, H2O, CO2, argon, ozone, trace gases

• Pollutants (particles)

• Heat energy in clouds

• Heat energy in gases

natural sources of gases

* **CO2** → decomposition, respiration, volcanoes, combustion


* **CH4** (methane) → wetlands, termites, oceans, tundra
* **N2O** (NOx) → soil, ocean
* **Ozone** → lightning, burning of biomass, soil

human sources of gases

• Vehicle emissions - fossil fuels

• Fuel combustion (energy)- fossil fuels

• Industrial processes

• Agriculture - cattle, sheep, rice (produce methane)

4 layers

stratosphere, troposphere, thermosphere and mesosphere

troposphere

(0-10km) first layer of atmosphere (lowest) Almost all weather occurs here

Stratosphere

(10-45 km): 2nd layer that contains ozone layer which absorbs UV;

Thermosphere and Mesosphere

• mesosphere - above stratosphere and zone of transition to space

• thermosphere - absorbs x-rays and short-wave UV radiation causing rising temperatures

standard lapse rate

temperatures decrease by an average of 6.5°C per km of altitude

temperature

density of atmosphere decreases with distance from earth

importance of atmosphere

shields earth from high energy, moderates the climate and redistributes water in hydrologic cycle

greenhouse effect

the process through which heat is trapped near Earth's surface by substances known as 'greenhouse gases

greenhouse gases

gases in atmosphere that trap heat include carbon dioxide, methane, water vapour and nitrous oxides.

albedo

Proportion of radiation reflected by a surface - linked to how white an object is

albedo affect

clouds reflect a lot of incoming solar energy = less solar energy to heat surface and atmosphere keeping earth cool. More water vapor = more clouds = more albedo

where do most reactions relating to living systems occur?

troposphere and stratosphere

Outline how changes in ozone, carbon dioxide and water vapor can have significant effects on ecosystems

* Increased water vapour can amplify the warming effect of greenhouse gases and leads to increased humidity
* Increased carbon dioxide traps more thermal energy in the atmosphere, warming the planet
* Increased ozone leads to reduced growth of plants and increased susceptibility to diseases and harsh weather

Outline the role of the albedo effect from clouds in regulating global average temperature

low albedo = more radiation from sun earth absorbs = temps rise

high albedo = more radiation returned to space and planet cools

• Low thick clouds = greater albedo (more reflectivity)

• high thin clouds = Lower albedo (more absorption)

Outline the role of the greenhouse effect in regulating temperature on Earth

Greenhouse gases keep our planet livable by holding onto some of Earth's heat energy so that it doesn't all escape into space. This heat trapping is known as the greenhouse effect. Just as too little greenhouse gas makes Earth too cold, too much greenhouse gas makes Earth too warm.