weather & climate: keywords

• air masses

  large areas of either warm or cold air; when met it can cause rain
• arctic maritime

  cold & moist air from north brings cold & damp weather
• arid

  area with little to no rainfall
• axial tilt

  over 40,000 years, angle of tilt changes- greater tilt means hotter summer & colder winters
• climate change

  long term movement in weather & climate patterns & average temperatures across earth
• climate cycles

  long term changes in the climate around the earth which can lead to glacial & interglacial periods
• coriolis force

  deflection of air movement caused by spinning of earth, creates the spinning wind pattern around low pressure systems
• atmospheric circulation

  general movements of air around earth due to pressure & temperature
• convection current

  movement of fluid caused by a difference in temperature or density
• coriolis effect

  effect of earth's rotation on wind movement
• cyclone

  tropical cyclone that hits oceania or madagascar
• drought

  prolonged lower than normal rainfall, leading to water shortages
• crop yields

  amount of crops produced; impacted by climate
• dendrochronology

  using tree rings to record changes in short-medium term changes in climate
• eccentricity

  over 100,000, there are changes in the shape of the earth's orbit_ more circular for warmer (interglacial periods) & elliptical for cooler (glacial periods)
• eustatic sea level change

  changes in sea level caused by melting ice & thermal expansion
• eye

  area of a tropical cyclone with extremely low pressure & calm conditions (middle)
• eye wall

  most intense winds and rainfall
• ferrel cells

  circulation cell that brings warm air from SOUTH to the UK
• glacial period

  long period in which ice advances due to colder temperatures
• glacial retreat

  shrinking of glaciers up the valley caused by warmer temperatures & low snowfall
• global circulation

  movement of heat ENERGY around the earth; has a major impact on weather & climate
• greenhouse effect

  impact of greenhouse gases on warming the earth
• greenhouse gases

  gas that absorbs & re-emits radiation, warming the earth's surface
• gulf stream

  warm ocean current that flows from the carribbean north into the atlantic
• hadley cells

  circulation cell near the equator causing storms at the equator
• hazard risk

  probability that a natural hazard will negatively affect a population
• hurricane

  tropical cyclone that hits the USA, latin america or caribbean
• hydrological drought

  reduced rainfall impacts water levels & cycle in a region
• interglacial period

  long period of warmer temperatures between glacial periods
• ice core

  cylinder of ice extracted from an ice sheet used to analyse past environmental conditions
• ITCZ

  area near the equator where trade winds from NE & SE meet
• jet stream

  fast moving current of air in the upper atmosphere
• low pressure system

  usually makes wet, windy weather as RISING AIR draws in WIND, causing HEAVY RAINFALL
• meteorological drought

  water shortages caused by lower than normal rainfall
• milankovitch cycle

  long term variations in orbit of earth inc eccentricity, obliquity (tilt) & precession (wobble of earth's axis)
• obliquity/axial tilt

  tilt of axis, changing from 21.5 to 24.5
• ocean currents

  movements of warm & cold water, transferring heat around the globe
• over-abstraction

  when humans take more water from the ground that is being replaced by rainfall
• polar cell

  circulation cell over the poles that brings cold air from the north to the uk