7.2 climate change - causes and impacts Flashcards
climate
- average weather over the long term at a regional level
weather
- conditions over a short time scale at a local level
factors impacting climate
solar radiation
- reduction in radiation, colder
factors impacting climate
tilting and orbit of earth
hemisphere tilted towards the sun
- absorbs more sunlight, summer
- opposite hemisphere tilted away, winter
factors impacting climate
atmospheric and ocean circulation systems
- more radiation reaches equator than polar regions
- energy from equator transferred towards the poles
- tricellular model, polar, ferrel, hadley
- el nino
factors impacting climate
GHGs
greenhouse effect
- rise in concentration in GHGs in the atmosphere
- more energy absorbed, raising global temperatures
factors impacting climate
volcanic activity
- short term impact on climate
- reflects solar radiation back into space, causes global cooling
positive feedback loops
water vapour
- temperature rises, more water evaporates
- water is a GHG causing hotter temperatures, more water to evaporate
ice albedo
- ice high albedo
- ice melts, reducing amount of solar radiation reflecting
- increases absorption of sunlight, warming, more ice melting
permafrost
- increase temperatures melt permafrost
- methane trapped in permafrost released, GHG
- methane increases temperatures
cloud cover
- high clouds, blanket retaining radiated heat from earthโs surface, increasing temperature
negative feedback loops
plant photosynthesis
- temperatures increase, more photosynthesis, more carbon dioxide absorbed, decrease temperature
cloud cover
- low clouds reflect solar radiation
increase in temperature precipitation
- increase in high latitudes and wet regions, flooding
- decrease in mid latitudes and dry regions, heat waves
increase in temperature sea level rise
- thermal expansion of oceans
- melting snow and ice
availability of water impacted by
- arid, reduce available water resources, evaporation, drought
- reduction in snow water storage, river flow
- saline intrusion of groundwater for coastal areas
higher water temperature
fishieries
- death of species, loss of biodiversity
- migration of fish towards poles
- change in spawning period
- coral bleaching, loss of habitat
ocean acidification
- dissolved oxygen reacts with water
- forms carbonic acid, hydrogen and bicarbonate ions
- increases water acidity, reproduction, growth, photosynthesis
- reduces available carbonate required by animals to form skeletons/shells