Earth & Space - Global Systems

What are the 6 layers of the Earth?

lithosphere, hydrosphere, atmosphere, troposphere, stratosphere and biosphere

What is the lithosphere?

The solid part of the Earth

What is the hydrosphere?

The water, sea, rivers, lakes etc

What is the atmosphere?

The air (nitrogen, oxygen etc). It consists of the troposphere (the lower atmosphere) and the stratosphere (the upper atmosphere). The density of the air decreases with height

What is the stratosphere?

The upper atmosphere that is warmer and contains ozone.

What is the biosphere?

The living parts of the Earth

What are the four cycles?

Water cycle, oxygen cycle, nitrogen cycle, and carbon cycle

What are the steps of the water cycle?

Evaporation, condensation, precipitation, surface runoff, transpiration, and groundwater

What is evaporation?

The change of water from liquid to water vapour (gas) that occurs in any water bodies

What are the forms of water precipitation?

Rain, hail, snow, sleet

What is condensation?

The change of water from a gas into a liquid, forming clouds. This occurs when it is cool enough.

What is transpiration?

The release of water vapour from leaves

What is surface runoff?

Water moving downwards across the surface of the Earth which helps distribute water, but potentially erode soils

What is groundwater?

Water under the surface of the Earth that picks up minerals and can be used for irrigation providing it is not too salty

What are the forms of carbon in the carbon cycle?

CO2, carbohydrates, proteins, fats/oils, fossil fuels (ie. crude oil, coal, methane/natural gas)

What are the steps of the carbon cycle?

photosynthesis, consumption, aerobic respiration, anaerobic respiration, decomposition, formation of fossil fuels, defacation, and combustion

What is photosynthesis?

carbon dioxide + water --(sunlight and chlorophyll)-> oxygen + glucose
It is a process completed by plants to provide them with food (glucose)

What is consumption?

Obtaining glucose from plants and other organisms

What is aerobic respiration?

glucose + oxygen --> carbon dioxide + water (+ energy)

What is anaerobic respiration?

Completed when insufficient oxygen is available
in animals: glucose --> lactic acid (+ less energy)
in plants: glucose --> alcohol + carbon dioxide (fermentation)

What is decomposition?

Releases carbon dioxide after breaking down complex molecules

What is the formation of fossil fuels?

Compression of biological waste to produce carbon-rich substances

What is combustion?

Releases CO2

What is the difference between weather and climate?

Weather is specific to a time and location and involves things like temperature, humidity, air pressure and rainfall. Climate involves general patterns over a period of time in a larger area/region.

What are the 4 things that affect the climate?

The tilt of the Earth's axis, the reflectiveness of the Earth, the Greenhouse effect, and ocean currents

How does the tilt of the Earth's axis affect the climate?

The tropics and equator receive more direct sunlight and are therefore hotter and more humid than near the poles where the sunlight is spread over a greater area and is less intense. The Earth revolves around the sun while the axis remains constant. The hemisphere tilted towards the Earth is in Summer as it receiving more direct sunlight and is hotter.

How does the reflectiveness of the Earth affect the climate?

The more reflective a part of the Earth's surface, the less light and heat that is absorbed by that part of the Earth. Light colours reflect heat, while dark colours absorb it.

How does the Greenhouse effect affect the climate?

When sunlight hits absorbent surfaces on the Earth, it is absorbed and radiated out as infrared radiation, which warms the Earth. These frequencies are absorbed by Greenhouse gases and retain the heat in our atmosphere, raising the temperature of the Earth.

How do ocean currents affect the climate?

Ocean currents move cool and warm water around the Earth, distributing it to different regions. They are caused and influenced by the moon's gravity, winds, rotation of the Earth, density of the water. There are two layers of ocean currents, with the upper layer being warmer and less dense and the lower layer being cooler and denser.

What is the formula for density?

D=m/v

How do salinity and temperature affect the density of ocean water?

Higher salinity of water increases the density as salts dissolve in the water and the ions fit into the gaps between water molecules to create a greater mass in the same volume.
When water is warmer, the molecules vibrate faster, pushing each other further apart and taking up a greater space to become less dense.

List 5 Greenhouse gases

Methane, carbon dioxide, water vapour, and ozone

How is the Greenhouse effect negatively enhanced?

By the increasing population, the bigger proportions of Greenhouse gases, and the creation of new Greenhouse gases (chlorofluorocarbons, CFCs)

What are the problems caused by the enhanced Greenhouse effect?

Rising sea levels due to the melting of glaciers and polar ice, which impacts coastal cities and low lying islands.
More frequent natural disasters (floods, droughts, hurricane, bushfires etc)
Much higher and lower peak temperatures (global warming)
Climate change impacting the timing of seasons causing problems for agriculture
Loss of habitats, changing migration patterns
Sea warming, coral bleaching and ocean water having a higher pH