OCR A-Level Geography Earth's Life Support Systems overview quiz quiz

Water freely crosses the planetary boundary into space and is continually replaced

The total volume of water is fixed and only redistributed between stores

It exchanges energy with space but never any matter at all

It contains no stores whatsoever, only continuous flows

Evapotranspiration

River discharge

Precipitation

Throughflow

The combined overland and channel surface runoff

The total precipitation falling on the basin

The suspended and dissolved sediment load carried by the stream

The change in water storage (soil and groundwater)

Photosynthesis, which uses water and fixes carbon

Chemical weathering of carbonate bedrock by rainwater

Longshore drift along the coastal sediment cell

Volcanic outgassing from deep mantle reservoirs

The slow cycle operates over days to centuries through respiration and photosynthesis exchange

The slow cycle moves carbon between rocks, deep ocean and atmosphere over millions of years

The slow cycle involves only photosynthesis by land and ocean plants

The slow cycle is confined entirely to the living biosphere

It permanently removes carbon from the atmosphere and buries it safely in deep ocean sediments

It has no real effect because the global carbon cycle is a fully closed system

It transfers slow-cycle carbon into the fast cycle far faster than it is naturally returned

It only affects the water cycle, not carbon

There is far too little vegetation present to supply any organic matter to the soil at all

The soil is permanently frozen and waterlogged year round

Rainfall is far too low to support significant plant growth

Rapid decomposition in hot, humid conditions recycles carbon quickly into vegetation

Decomposition is even slower than production, so organic matter accumulates in frozen permafrost

Productivity is actually very high here, rivalling that of dense tropical rainforest biomass each year

Carbon is continually imported from rainforest regions by global wind and ocean currents

Frequent volcanic activity steadily adds large amounts of new carbon to the tundra soil

It remains permanently locked in ice even as surface temperatures rise sharply year on year

Decomposition releases carbon dioxide and methane, risking a switch from sink to source

It is quickly absorbed by the surrounding oceans with no measurable effect on the atmosphere

It is compressed and slowly turns into new fossil fuel deposits

A warming of surface waters only, driven by absorbed solar radiation each summer

A steady rise in ocean salinity as evaporation outpaces freshwater inputs worldwide

A fall in ocean pH as dissolved carbon dioxide forms carbonic acid

The accelerating melting of polar and Arctic sea ice

Mitigation manages the consequences of warming, while adaptation works by cutting emissions at source

They are essentially the same thing, and the two terms are used interchangeably in climate policy and practice

Mitigation only applies to the water cycle, never to the carbon cycle

Mitigation tackles the cause (cutting emissions or enhancing sinks); adaptation manages the consequences

Carbon dioxide persists for centuries, so emissions accumulate and their warming is locked in

Carbon dioxide is removed from the atmosphere within days, so the timing of cuts barely matters

Delayed action is cheaper and just as effective at avoiding total warming in the long run

Warming is essentially unrelated to atmospheric carbon dioxide concentrations