Atmosphere and Weather Flashcards
factors affecting diurnal energy budget (6)
insolation reflected solar radiation energy absorption long wave radiation sensible heat transfer latent heat transfer
what insolation and how does it affect the durinal energy budget
insolation is incoming shortwave radiation form the sun. Areas where there is high insolation would have a larger diurnal energy budget.
factors affecting insolation(4)
- the energy being released by the sun
- the distance the earths is from the sun as our orbit is oval
- the altitude of the sun
- latitude and seasons
what is reflected solar radiation (albedo) and how does it affect the diurnal energy budget
albedo is the percentage of energy reflected back into the atmosphere when there is high albedo the energy budget increases as more energy is reflected back so there is more heat ( energy) in the atmosphere at a given time
what is subsurface absorption and how does it affect the diurnal energy budget
surface absorption is the the energy absorbed by surfaces such as dust particles , clouds water bodies and land
areas where there is low absorption would have a higher energy budget as less of the insolation is absorbed so more is left in the atmosphere.
what is long wave radiation and how does it affect the diurnal energy budget
this the type of radiation that comes from the earth after it has been heated up which can be absorbed by green house gases but it does not have a direct effect of the energy budget it is the green houses gases that have an effect on the energy budget
what is sensible heat transfer and how does it affect the energy budget
sensible heat transfer is the energy required to change the temperature of a substance without a change in phase. the earth reradiates and heats up the air above it.
the less sensible heat transfer the greater the energy budget
what is latent heat transfer and how does it affect the energy budget
latent heat is the energy absorbed by or released from substance during the change of phase
the changing into a more solid state increases the energy budget as heat is released into the atmosphere but when the change of state is more disordered the energy budget decreases.
factors affect the global energy budget
latitude
pressure belts and wind belts
ocean currents
landuse and green houses gases
why do some areas have a radiation deficit and some have a surplus
due to the curved nature of the earth some areas further away from sun than others so they receive a more concentrated form of insolation. at higher latitudes where the sun is further from the land the the insolation has to travel a further distance so there is a greater chance of dissipation.
how do pressure belts and wind belts relate
wind moves towards areas of low pressure
describe pressure belts and how they affect weather
wind circulates in each hemisphere in 3 distinct cells due to convection, Hadley cells(thermal equator -30), polar cells (60-90) and the Ferrell cells (30-60). the points at which air rises there is low pressure and the are at which air sinks there is high pressure. Areas of low pressure are known as the doldrums
the cells generate areas of higher and low low pressure can affect local weather as when air sinks the conditions are known as anticyclonic so at high pressure the weather is generally mild as air needs to rise for most weather conditions to occur .
describe the wind belts and how do the transfer energy
the three cells generate wind belts which are the polar easterlies, trade winds and the prevailing westerlies. the trade winds are found between -30 and 30 and come towards the equator. they come form the NE in the northern hemisphere and the SE in the southern hemisphere due to the Coriolis force
the westerlies are found between 30 and 60 and are as a result of the Ferrell cells. they move in the opposite direction to the trade winds and are usually the cause of monsoon winds
the polar easterlies come form the poles and move away form them to 60 degrees as a result of the polar cells. they bend towards the east because of the Coriolis effect.
because of sensible heat transfer the air is transfers the heat energy from it area of origin to its destination .
The Coriolis effect makes wind systems twist counter-clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere
describe the ocean currents and how they affect temperature variations (you need to say an example )
sea water is heated at the equator and becomes less dense and moves north and south toward the poles and get colder and sinks . Warm ocean currents circulate around their ocean basin in a clockwise direction in the northern hemisphere and anticlockwise in the southern hemisphere.
the circulation of the ocean currents heats up or cools the are around it is the reason why some coastal areas have different temperatures in winter and summer than would be expected given their latitude. for example the eastern coast of north and south America have higher temperatures in winter as extra heat is supplied by the warm current circulating it and during the summer they have lower temperatures and the sea has a higher specific heat capacity so absorbs the extra heat.
how does land and sea distribution affect seasonal variation in temperature
land has Lower reflectivity, so more absorption of radiation (apart from ice) . Heat confined to near surface as surface has poor conductors. Low specific heat capacity, so a set amount of energy raises land temp by more. Less water, so less energy wasted to evaporation
sea has a Higher reflectivity, so less absorption of radiation (especially with low sun). Sun’s rays penetrate deep, convection currents distribute heat to great depths. High specific heat capacity, so set amount of energy raises temp by less. Large amounts of energy used for evaporation
