ESS Standard Topic 4.1

System

A Set of interrelated parts working together to make a complex whole

Storages

The stock of a system and is represented by boxes

Inputs and Outputs

Matter or Energy coming into or our of a system

Flows

Exchange of matter or energy between storages and represented by arrows

Transfers

When energy or matter flows and changes location but does not change state.

Tranformations

When energy or matter flows and changes states - a change in the chemical nature, a change in state or a change in energy

Hydrosphere

Term to describe all the water on the planet

The water cycle recycles water through ecosystems ensuring there is fresh water.

What two forces drive the Hydrological Cycle

• Heat - (Evaporation, Transpiration, wind)

• Gravity - (Leaching through the soil, runoff, precipitation)

Turnover Time

The time it takes for a molecule to enter and leave a particular part f the system

● Oceans: 37 000 years

● Ice Caps: 16 000 years

● Groundwater: 300 years

● Rivers: 12 - 20 days

● Atmosphere: only 9 days

Precipitation (Transfer)

Vertical movement of water falling onto the Earth from the atmosphere.

Surface Runoff (Transfer)

Movement of water from over ground surface into rivers and streams due to impermeable surfaces

Infiltration (Transfer)

Movement of water from surface through soil

Percolation (Transfer)

Movement of water from the surface through porous rocks or sediments (into aquifiers)

Stream-flow (currents) (Transfer)

Movement of water from streams to rivers/lakes/oceans/seas

Throughflow (Transfer)

Movement of water through the soil into rivers

Advection

Horizontal Movement of water in all states driven by Wind

Evapotranspiration (Transformation)

The evaporation of water from organism/soil and from plants into the atmosphere

Sublimation (Transformation)

Solid → Gas

Tends to happen up in the mountains at lower pressures or at he poles

Evaporation (Transformation)

Liquid → Gas

Water at the surface of water bodies evaporates into the atmosphere

Condensation (Transformation)

Gas → Liquid

Water vapour in atmosphere → water in cloud

Hydrological Storages

● The oceans (96.5%)

● Glaciers and ice caps (1.7%)

● Groundwater (1.7%)

● Surface freshwater (0.02%)

● Atmosphere (0.001%)

● Organisms (0.0001%)

Aquifer

Made of permeable rocks, sandstone and other porous rock where water is easily able to move around in an underground drenched storage area.

Renewable Water Stores

• Atmosphere

• Rivers

Non Renewable Water Stores

• Ocean

• Ice Caps

Link between renewability and water

Water can easily move from being renewable to bing non-renewable if poorly managed.

E.g. Groundwater Aquifers - it takes longer than the human lifetime to replenish water extracted.