R Flashcards
Radiation
The emission of energy as electromagnetic waves.
Radial drainage
A pattern of streams radiating from a central point or area e.g. off a mountain.
Radiation fog
A fog formed when warm moist air is cooled to the dew point by the ground.
Rain
Liquid precipitation from the atmosphere in drops of at least 0.5mm in diameter.
Rain gauge
An instrument used to quantify the amount of rain falling in a particular location over a period of hours.
Consists of a beaker marked out in millimeter intervals and a funnel leading into it.
The beaker will be set in open ground to avoid water from drips or splash.
Rainshadow
The area on the leeward side of a mountain range which experiences drier conditions than the windward side.
This is due to the air being drier as it has experienced condensation and precipitation on the windward side, plus the fact that the air will be sinking and therefore warming meaning relative humidity is falling and condensation cannot occur.
Rainsplash
Soil erosion caused by the force of impact of raindrops.
Raised beach
A relict beach left dry by a relative fall in sea-level.
Ramsar Convention
The Convention on Wetlands of International Importance especially as Waterfowl Habitat held at Ramsar in Iran in 1971.
Now known as the Convention on Wetlands.
Seeks to identify, conserve and use wisely, areas of wetland that may be under threat from human encroachment.
The Convention entered into force in 1975 and had 158 signatories lodged with UNESCO by 2009.
www.ramsar.org
Ranching
Vast, extensive livestock farms, usually found in remote, marginal areas which are not viable for other types of farming.
Range
In human geography, the maximum distance that people are willing to travel to obtain a good or service.
Accuracy is limited by multiple local factors plus the subjective nature of the idea, but generalizations can be drawn.
Rank-size rule
The size of a settlement is inversely proportional to its rank i.e. the second largest city is half the size of the largest etc.
If the largest city is much larger than all others, primacy exists.
If two cities are broadly similar and larger than all others then it is said to be a binary situation.
Rationalization
The reorganization of a company to increase efficiency, usually by cutting costs especially labour costs.
Ravine
Deep, steep-sided valley, gorge or cleft cut into a rocky landscape.
Raw materials
Unprocessed inputs to an industrial process.
Reforestation
This is the restocking of existing forests and woodlands which have been depleted, with native tree stock.
Reclaimed land
Artificial land created in coastal areas.
Recreation
Any activity people do during their leisure time. Some definitions require it to be activities away from home but that take up less than a day, after which they become tourist activities.
Recreational forest
Forests maintained for recreation activities such as bird-watching, cycling, horse-riding, camping etc.
Recycling
The re-use of materials that would otherwise be deemed rubbish.
Redevelopment
The regeneration of urban areas that have fallen into poverty and disrepair.
It may involve renewal of existing infrastructure, or wholesale demolition and rebuilding.
Red tide
A bloom of surface algae, red in colour, found in coastal waters when a heavy nutrient load is washed from the land stimulating the algal growth.
Reduction
A chemical reaction involving the removal of oxygen.
Refraction
The tendency for waves to become more parallel to the coastline as they approach it.
Caused by the slowing of waves at their base as they enter shallower water.
Refugee
A person who flees their home country through a fear of persecution on the grounds of race or religion, or membership of some other group.
Regelation
The refreezing of water into ice after pressure which caused it to melt is released.
Regeneration
See redevelopment.