hydrosphere and atmosphere

what is Water Vapour

Most abundant variable gas in the atmosphere.

Melting Ice

Requires energy intake, cools the environment.

Energy Transfer

Water's different forms facilitate energy movement.

Condensation

Releases energy, warms the environment.

Latent Heat

Energy stored in water vapour during phase changes.

Absolute Humidity

Mass of water vapour per volume of air.

Saturation Pressure (es)

Maximum water vapour pressure at saturation point.

Relative Humidity (RH)

Actual vapour pressure compared to maximum capacity.

Clausius-Clapeyron Formula

Describes relationship between temperature and saturation pressure.

Dew Point

Temperature at which air becomes saturated with moisture.

Adiabatic Process

No energy exchange between system and surroundings.

Dry Adiabatic Lapse Rate

Temperature decreases 10°C per km rise without moisture.

Moist Adiabatic Lapse Rate

Temperature decrease affected by condensation and expansion.

Convection

Warm air rises; cold air sinks due to density.

Cloud Formation

Occurs when air parcel reaches saturation during ascent.

Air Pollution

Stable atmosphere traps pollutants, reducing air quality.

Unstable Atmosphere

Pollutants mix upwards, improving air quality.

Stable Atmosphere

Pollutants spread horizontally, worsening air quality.

Turbulent Motions

Mix pollutants widely in unstable atmospheric layers.

Hydrological Cycle

Movement of water through evaporation, condensation, and precipitation.

Radiative Budget

Energy balance affecting Earth's climate and temperature.

Energy Movement

Driven by changes in water phases and temperature.

Mean wind field

the general circulation of the atmosphere

Pressure gradient force

force always directed from high to low pressure

Pressure gradient force (PGF)

In a region of high pressure, PGF is directed outward; in a region of low pressure, PGF is directed inward

Sea breeze

the increased amount of air pushed out to sea aloft will cause a higher pressure at the surface over the sea than over the land

Coriolis force

Air in the Northern Hemisphere will be deflected to the right of the direction of motion; Air in the Southern Hemisphere will be deflected to the left of the direction of motion

Geostrophic balance

defined as the balance between the pressure gradient force and Coriolis force

Geostrophic wind

wind parallel to the 'isobars' and wind speed is proportional to the pressure gradient

Effect of friction at the surface

friction always opposes direction of motion

Wind convergence

Wind will 'converge' into the low pressure at the surface causing air to lift (clouds and precipitation)

Wind divergence

Wind will 'diverge' from high pressure causing air to sink ('clear skies')

Global wind patterns

general circulation from averaging the winds over long period of time

Upper-level pressure

higher heights at equator and lower heights at the poles

Jet streams

strongest in winter with temperature/pressure gradient max in the troposphere

Surface pressure and precipitation

lows = increased precipitation; highs = dry areas (deserts)

Large-scale circulation

temperature induced pressure gradients set up a circulation called Hadley cells

Intertropical Convergence Zone (ITCZ)

area of high precipitation/rainforests

Trade winds

at equator (from NE in NH and from SE in SE - overall an east -> west wind)

Affect on communities

semi-permanent features affect communities and lifestyle

Indian Monsoon

moist air from ocean to South Asian subcontinent produce heavy precipitation (monsoon)

Permanent gases

Gases that do not change significantly over time.

Variable gases

Gases that fluctuate with location and time.

Mole fraction

Ratio of moles of substance to moles of dry air.

Parts-per-million (ppm)

Measurement unit for carbon dioxide concentration.

Parts-per-billion (ppb)

Measurement unit for methane and nitrous oxide.

Parts-per-trillion (ppt)

Measurement unit for trace gases like CFCs.

Keeling curve

Graph showing rising carbon dioxide levels over decades.

Photosynthesis

Process that lowers CO2 levels during summer months.

Hydroxyl radical (OH)

Cleansing agent that reacts with methane in summer.

NH-SH gradient

Difference in atmospheric conditions between hemispheres.

Sequestration

Long-term storage of carbon dioxide in the Earth.

Global warming potential

Comparison of gases' ability to trap heat.

Ozone layer

Region of Earth's stratosphere with high ozone concentration.

Chapman mechanism

Proposed mechanism for ozone formation and depletion.

Ozone depletion

Reduction of ozone concentration in the stratosphere.

Montreal Protocol

International treaty to phase out ozone-depleting substances.

Ozone hole

Significant depletion of ozone layer over Antarctica.

Chlorofluorocarbons (CFCs)

Compounds used in refrigeration, harmful to ozone.

Particulate matter (PM)

Airborne particles classified by size (PM2.5, PM10).

Nitrogen oxides (NOx)

Gases that contribute to air pollution and ozone formation.

PM2.5

Fine particulate matter that penetrates deep into lungs.

PM10

Larger particulate matter that is less harmful than PM2.5.

Air pollution impacts

Health effects including respiratory and cardiovascular diseases.

UK PM emissions

Significant reduction in particulate matter emissions.

whats the difference between climate and weather

climate is what you expect, weather is what you get

How many years of weather is climate

30

what drives weather

laws of physics

what are the three laws of physics

conservation of energy, mass and momentum

what variables used to measure the atmosphere

temperature, pressure, wind velocity

what does the vertical structure of the lower atmosphere mean

dictates how energy is transported in the atmosphere

where is the highest pressure in the lower atmosphere

at the surface

what two types of gases make up the atmosphere

permanent and variable

what type of reactions make up the ozone layer

Chapman reactions

what plays a key role in chapman reactions

UV

what happens to temperature as you move away from the surface through to the thermosphere

decreases up to the troposphere

starts to rise in the stratosphere

decreases through the mesosphere

increases in the thermosphere

what is planck's law

describes amount of radiation and as a function of wavelength for a given temperature

what is the albedo effect?

ability of a surface to reflect away solar radiation

what is a black body

an object that emits all radiation that it absorbs

what is the Stefan Boltzmann constant

E = esT4

during the day what happens to surface radiation

warms lowest few mm by conduction and then convection

highest temp is closest to the surfac

at night what happens to surface radiation

surface cools by emission of radiation

cools lower atmosphere by conduction

coldest temp closet to the surface

whats the difference between the heat capacity of water vs land

water is 5x higher than land

what is a Flood

Overflow of water submerging normally dry land.

what is River flooding caused by

caused by excess water flow in rivers.

what flows cause excess water flows

excess overland flows, saturation excess overland flow, fast throughflow

what is Surface water flooding

Flooding from rainfall, not involving rivers.

what is Groundwater flooding

Occurs when water table rises above land surface.

what are Coastal storm surge floods

Floods caused by low pressure and high winds.

what are Dam break floods

Floods from the failure of a dam structure.

what are Tsunamis

Large sea waves caused by underwater disturbances.

what are Flood risk factors

land cover

basin size and shape

soil type

antecedent conditions

aquifers

what is a Flood hazard

Natural climate periods affecting flood frequency.

why is flood risk increasing

changing hazards and human induced climate change

what is the impact of a changing climate on Urbanisation

Increased flood risk due to urban development.

what is the impact of a changing climate on Floodplains

changing exposure - Population living in areas prone to flooding.

why is Vulnerability to floods increased with a changing climate

increased Risk due to assets and adaptability of local populations.

what are the impacts of flooding on societies with low protection

tend to resettle further away from the river

what are the impacts of flooding on societies with high protection

no significant changes

what is a Drought

Lack of water compared to normal hydrological conditions.