week 5 Flashcards
what is the atmosphere
a mixture of gas and suspended particles combined with falling precipitation. it facilitates energy and mass between other spheres
why is the atmosph important
-protective layer from UV/ space objects
-green house effect for stable temps
-weather
-our atmos has the chemistry that allows us to breathe
what are the main comps of air
N =78.08%, O=20.95%, H2O=1-4%,
what are the components of air that play a large role
CO2, CH4, O3, NO2
H2O gas
able to vary in the atmos. depending on the region and cloud density. has the ability to absorb outgoing radiation = pos feedback
CO2 gas
a trace gas (400ppm) which absorbes outgoing solar radiation
sourced from: respiration, volcanoes, decomposition, anthropogenic combustion, deforestation…
though it is commonly stored in sinks (soil, forests and oceans)
O3
trace gas with a max of up to 15ppm that absorbs UV rad. very fragile which in the presence of CFC
CH4
a very potent gas (21x more powerful than CO2), though very scares in the atmos
commonly from agricultural (cows) and permafrost thaw (pos feedback)
since 1750= 150% inc
aerosols
fine solid or liquid particulate matter that is suspended in the air
it can be sourced from natural events like volcanic eruptions or from anthropogenic activities
climate vs weather
the climate is the long-term average of the weather recorded over a number of years. generally, the climate is associated with a larger region.
weather is the short-term environmental (atoms) conditions that commonly happen to a local region.
what causes weather/clmaite
changes in the energy stored in the atmos. all dependent on the input vs the output. lager/ rapid increases in trace components of the atmos can alter the typical patterns, inducing unpredicted effects
how does volcanism affect the atmos
1) short-term cooling due to the release of aerosols. aresol refect/ block radiation (insolation)
2) longer-term waring do to the high release of GHG
how dod GHG work- where do we get our energy from
GHG effectively traps solar radiation (wavelengths) and heat emitted from the plant’s surface. In turn the gases warm as radiate energy back down to the plants surface
note that all GHG trap heat differently and have longer residence times of the heat
Heat vs temp
Heat is energy. temp is a measurement of energy within a system
how is heat dispersed across the earth
the temp of the earth is a complementary relationship with the latitude of the region of interest. polar regions received the same energy as the equatorial regions, though its spread across a greater SA
what impacts temp
alteration of day (sunexposure)/ weather
angle of axis in relation to sun
albedo of SA
wether is it a coastal region or not
how much solar rad reaches the earth surface
50 reaches the surface but:
approx 30 is reflect by the almost and clouds
20 is abourbed by clouds and atmos
what is the Keeling curve
a graphical representation of the avg increase of CO2 conc with respect to seasonal CO2
why does our climate change
1) fluctuation is solar rad (sun flares)
2) Milankovitch cycles
3)atmospheric composition changes
Milankovitch cycles
Variation in Earths climate (ice age cycles releasing CO2 due to alterations in earth’s orbit about the sun)
-not perfectly circle
-obliquity = earth’s tilt changes btwn 22-24.5
-precession= wobbling of the rotational axis
what cuases atmospheric composition changes
anthropogenic forces
natural causes (volcanoes)
feedback loops (permafrost melting)
what are the three classic climate zones
frigid
temperate
torrid
what are feedbacks
cyclic responses to an initial force that will amplify or reduce the effect.
albedo
1+ prefect reflector (very bright)
0= perfecte absorber
what is permafrost
ground that remain sub-0 for more than 2years. commonly permafrost contains a mass amount of CO2 and CH4, and the melting of this causes a strong feed back loop of global warming.
What is eccentricity
The shape of the earths orbit around the sun
