-
The earth formed approximately
4.5 billion years ago
-
The solar system formed approximately
4.6 bya
-
the atmosphere formed primarily
by degassing of earth's mantle
-
which 3 gases constitute most of the atmosphere near earth's surface?
nitrogen, oxygen, argon
-
where does the atmosphere's dioxygen come from?
photosynthesis
-
residence time is
the time it takes to fill a reservoir, once emptied
-
what is the residence time of CO2 in earth's atmosphere?
400 yrs
-
What is the residence time of H2O vapor?
10 days
-
What is the defining characteristic of of GHG?
absorbs long wavelength radiation from earth's surface
-
what are 3 most important GHG?
water vapor, ozone, methane
-
in a closed system, energy is always
conserved
-
heat is
the process of transferring energy through thermal contact
-
which of the following modes of heat transfer requires physical medium?
radiation
convection
conduction
convection and conduction
-
the moisture content of the atmosphere
increases sharply with temperature
-
why does anthropogenic CO2 matter for climate?
it absorbs longwave radiation and has a long residence time in the atmosphere
-
climate change always results from
any long-term imbalance between incoming and outgoing radiation
-
Stefan-Boltzman's law states that a physical body above the temperature of 0K emits an energy flux whose intensity varies
as the fourth power of temperature
-
Wien's displacement law states that
hotter objects radiate at shorter wavelengths
-
the earth receives ___ radiation from the sun, emits ___ radiation
-
which of these is not present in a beam of sunlight?
near-infrared radiation
long-wave radiation
short-wave radiation
electromagnetic radiation
long-wave
-
the planetary albedo is defined as
the fraction of solar radiation reflected by the earth
-
the poles are colder than the equator because
the earth's curvature leads to beam spreading
-
as the earth revolves around the sun, it experiences seasons because
the earth's axis is tilted
-
when are latitudinal insulation contrasts the greatest?
solstices
-
the greenhouse effect is a popular term for
the trapping of earth's outgoing longwave radiation due to GHGs
-
what avg temp would earth be w/o an atmosphere?
-18oC
-
What is the earth's average temp?
+14oC
-
what planet is a dramatic example of "runaway greenhouse effect"?
venus
-
which process primarily explains the "runaway greenhouse effect"?
water vapor feedback
-
specific heat is defined as
the quantity of energy required to raise 1kg of a substance's temp by 1K
-
why is the ocean able to store so much heat?
- 300x mass of the atmosphere
- specific heat 4x dry air's
-
in the climate system, thermal energy is defined as the sum of
latent and sensible energies
-
energy is measured in
joules
-
when do clouds form?
- when a large amount of water vapor is added to an air parcel
- when cooling lowers the saturation vapor pressure to the point where air parcels become saturated
-
the pressure gradient force pushes air
from regions of high pressure to regions of low pressure
-
in the northern hemisphere, Coriolis force
deviates air parcels to the right
-
the unit measuring force named after which scientist?
newton
-
atmospheric pressure is a measure of the atmosphere's
weight
-
what is the effect of clouds on climate?
it depends on the ratio from low vs high clouds
-
what is the ultimate cause of the general circulation of the atmosphere?
radiation imbalances b/w the tropics and high latitude
-
on average, hadley cell best described
- ascending motion near equator
- descending motion near 30 degrees
- surface easterlies
-
poleward heat transport is accomplished by
- hadley cell
- wind-driven oceanic circulation
- thermohaline circulation
-
without poleward heat transport, the equator-to-pole temperature gradient would be
enhanced
-
what are the drivers of oceanic circulation?
- density differences
- wind stress
-
why are the world oceans important to understand climate?
- heat transport
- heat storage
-
what is the Ekman transport?
wind-driven mass transport in upper ocean
-
how is Ekman transport oriented with respect to wind (in southern hemisphere)?
-
what is thermohaline circulation?
ocean circulation due to lateral differences in temperature and salinity
-
why is thermohaline circulation important for climate?
- it transports heat northward to the nordic seas, explaining why norway's coast is free of permanent sea-ice cover
- it can play a role in abrupt climate change because of its sensitivity to freshening
- it also carries CO2 into the deep, sequestering it from the atmosphere
-
polewards of 20 degrees latitude, most of the heat transport is accomplished by the
atmosphere
|
|
