20. Climate Change Flashcards
What did Einstein say about energy? What does this mean for any system?
Energy cannot be created or destroyed: it is conserved
Energy input- energy output = change in energy storage
rate of energy addition- rate of energy subtraction=
rate of change of stored energy
more ___wave energy is absorbed in the tropics, and __wave emission is relatively smaller
short
long
For any planet in space, energy input=
solar radiation absorbed
for any planet in space, energy output=
solar and longwave radiation lost to space
T/F
If the stored energy on a planet is not changing, then energy input= energy output
true
Absolute zero=
the lowest temperature possible. At a temperature of absolute zero, there is no motion and no heat
0 degrees kelvin/ -273C
What must be true for an object to emit longwave radiation?
any object that contains heat (ie is above absolute zero) emits longwave radiation
At what rate does an object emit longwave radiation?
Emits LW radiation at a rate proportional to its temp
L=σT^4 over its entire area
The steady state global energy balance assumes energy stored ___(is or is not changing)
NOT changing
Give the equation for earth’s energy balance
write it down
Based on the Earth’s energy balance equation, what is the temperature required for the Earth’s outgoing radiation to balance the incoming solar radiation?
255K or -18C
This is not the actual avg temp of the earth!
Earth’s average temp is 33C warmer than it should be according to the earth energy balance equation. Why?
Because for that equation, we assume no atmosphere, which is not true.
Greenhouse effect!
T/F
The atmosphere easily transmits solar radiation but almost completely absorbs earth’s longwave radiation
true
What kind of radiation does earth’s sfc emit? Is it absorbed?
longwave radiation
it’s absorbed by certain atmospheric gases and clouds
*the atmosphere almost completely absorbs outgoing LW
T/F
The atmosphere emits LW radiation in one direction: out to space
false
emits LW in ALL directions, including back towards earth, heating it
Give the 5 primary gases that absorb earth’s outgoing LW radiation. What are these known as?
- H2O (water vapor)
- CO2
- CH4 (methane)
- N2O (nitrous oxide)
- O3 (ozone)
= The Greenhouse Gases
Explain what happens to the heat when more GHG are present in the atmosphere
More LW radiation is absorbed by these atmospheric GHG, so less heat energy is emitted to space. This results in the Earth’s temp increasing
Climate=
avg atmospheric conditions that prevail in a region over extended time span (usually min 30 yrs)
Give the 5 main components of the earth system.
These components determine climate
Atmosphere
Vegetation
Ice
Ocean
Land Surface
When one component of the Earth climate system changes, what happens to the others?
When one component changes, the others react (likely also change)
Changes in the 5 components of the climate system are analyzed in terms of which 2 things?
Cause (forcing)
and
effect (response)
Describe what “climate forcing” is
= a factor that causes changes in the climate system (energy budget)
eg. differing sun cycles, changes in albedo, etc
How often do earth-orbital changes occur? Do these contribute to alternating glacial/ interglacial periods or not?
occur over 10s to 100s of thousands of years
yes
