A2 Geography Weather and Climate

order of the atmospheric layers

troposphere, stratosphere, mesosphere, thermosphere

acronym for order of atmospheric layers

tsmt

troposphere

8-12km, temps drop by 6.5 degrees every 1000m, winds increase and pressure falls going up, unstable due to clouds, pollution, water vapour and dust

stratosphere

20-30km, more stable, temperature increases with height due to concentrated solar radiation, winds increase and pressure falls going up

mesosphere

temps fall again due to reduced ability to absorb energy

thermosphere

above 90km, temp increases from better uv absorption, final layer

atmospheric heat budget

balance between incoming solar radiation and outgoing radiation

insolation

incoming solar radiation

global atmospheric circulation model process

hot air rises at the equator until dew point, rain falls at low pressure, trade winds carry north where cooler air sinks causing higher pressure

where is the uk located on gacm

between polar and ferrel

which way does coriolis force bend winds

east in northern hemisphere

factors affecting climate and seasons

latitude, continentality, altitude, cloud cover, ocean currents, prevailing winds, jet streams, itcz, la nina el nino, tilt,

continentality

daily changes to land monthly to oceans, as they take longer to absorb and release heat, coastal areas have cooler summers and warmer winters

altitude

expansion in volume lower pressure causes fall in temperature, decrease in airs ability to hold heat

ocean currents

north atlantic drift aka gulf stream brings warmer temps to the uk, move in circular motions called gyres

prevailing winds

depends on direction, eg winter from land is colder

tilt of earth

23.5 degrees, winter solstice means north is tilted away

la nina or el nino

enso = el nino southern oscillation, variations in trade winds across pacific, el nino means warmer across s america so jet stream south in usa bringing low pressure

itcz

intertropical convergence zone between hadley cells, windy low pressure, moves n and s seasonally, affected by the heat equator

heat equator

highest land temps from overhead position of the sun

rossby waves

meanders in jet streams

zonal index

strength of mid latitude winds

monsoons

wet season = itcz moves into region bringing low pressure and moist winds from ocean, orographic uplift exacerbates rainfall

factors affecting vulnerability

infrastructure, education, governance, wealth, proximity, healthcare, transport, comms, technology and planning capabilities

fema

federal emergency management agency, usa

exception of wealthy at less risk

coastal areas often popular

hurricane ida facts

2021, cayman islands and louisiana, 277kmph, up to 250mm rainfall in louisiana

economic impacts of hurricane ida

65 bil usd damages, 478km squared sugarcane crop nearly a third of harvest, 90% of oil production in gulf of america destroyed

social impacts of ida

pressure on hospitals from covid 19

environmental impacts of ida

oil spill from damage to offshore drilling site, coastal erosion

responses to ida

new orleans flood defences strengthened after katrina, new levees withstood storm surges, 5000 national guard members helped search and rescue, investment into flood prevention and consideration of low lying land use

australian drought

2015-16, aquifer depletion, murray darling river basin, holding 70% water and 40% of agricultural produce, crop failure imports needed rising prices, mangroves gone, investment into desalination plants, perth pumps 10% of treated wastewater into ground providing a natural filter

australian bushfires

2019-20, up to 19 mil hectares burnt, 3000 homes damaged, 3 bil animals, wwf raised over 50 mil, hottest and driest year on record

impacts on air quality

particulates from traffic reduce income solar radiation by up to 20%, acid rain from sulfur dioxide through fossil fuels, carbonation of buildings with limestone like the taj mahal, health problems

reducing human impact of air pollution

catalytic converters, electric cars, alternative energy, clean air acts, congestion charges, emission tests as part of mots

sea ice free arctic summers fact

once every 100 years if 1.5 increase, once every 10 years if 2 increase