CLIMATE/EARTH 401�Geophysical Fluid Dynamics�Dynamical Meteorology
Pictures: Waves, Weather, and Climate
Building the Radiative Balance
Redistribution by atmosphere, ocean, etc.
SURFACE
2) Then it is redistributed by the atmosphere, ocean, land, ice, life.
Top of Atmosphere / Edge of Space
ATMOSPHERE
CLOUD
RS
1) The absorbed solar energy is converted to terrestrial thermal energy.
Another important consideration
Latitudinal dependence of heating and cooling
SURFACE
ATMOSPHERE
CLOUD
Equator
(On average heating)
North Pole
(Cooling)
South Pole
(Cooling)
Because of tilt of Earth, Solar Radiation is absorbed preferentially at the Equator (low latitudes).
Top of Atmosphere / Edge of Space
After the redistribution of energy, the emission of infrared radiation from the Earth is ~ equal from all latitudes.
Transfer of heat north and south is an important element of the climate at the Earth’s surface
Redistribution by atmosphere, ocean, etc.
SURFACE
Top of Atmosphere / Edge of Space
ATMOSPHERE
CLOUD
heat is moved to poles
cool is moved towards equator
cool is moved towards equator
This is a transfer. Both ocean and atmosphere are important!
This predisposition for parts of the globe to be warm and parts of the globe to be cold means that measuring global warming is difficult. Some parts of the world could, in fact, get cooler because this warm and cool pattern could be changed.
Scientific Method
Weather and water
Grange, October 2006
(1930-1961)
[from the National Atlas (1970)]
Transfer of heat north and south is an important element of the climate at the Earth’s surface.
Redistribution by atmosphere, ocean, etc.
SURFACE
Top of Atmosphere / Edge of Space
ATMOSPHERE
CLOUD
heat is moved to poles
cool air moved towards equator
cool air moved towards equator
This is a transfer. Both ocean and atmosphere are important!
Large scale weather systems transport large quantities of thermal energy from equator toward the poles
Tropospheric Mean Meridional Circulation
This is not exactly physical but is a common conceptual model.
mean meridional circulation
This is (more) physical representation of the mean circulation of the atmosphere.
Conceptual/Heuristic Model
Plumb, R. A. J. Meteor. Soc. Japan, 80, 2002
Yields
Relationship between parameters if observations and theory are correct
Dynamic atmosphere: �Hurricanes --- Vortices
Hurricanes and heat�Sea Surface Temperature�(blue cool / warm orange)
Hurricanes and heat
Mid-latitude cyclones - waves
Mid-latitude cyclones & Heat
Ocean Surface Currents�(From Steven Dutch, U Wisconsin, Green Bay)
Good Material at National Earth Science Teachers Association
The Thermohaline Circulation (THC) �(Global, organized circulation in the ocean)�(The “conveyer belt”, “rivers” within the ocean)
Where there is localized exchange of water between the surface and the deep ocean (convection)
Warm, surface currents.
Cold, bottom currents.
Green shading, high salt
Blue shading, low salt
What goes on vertically?
Some basics of the atmosphere
Troposphere: depth ~ 1.0 x 104 m
Troposphere
------------------ ~ 2
Mountain
Troposphere
------------------ ~ 1.6 x 10-3
Earth radius
This scale analysis tells us that the troposphere is thin relative to the size of the Earth and that mountains extend half way through the troposphere.
An estimate of the January mean temperature
north
winter
south
summer
tropopause
stratopause
mesosphere
stratosphere
troposphere
note where the horizontal temperature gradients are large
An estimate of the January mean zonal wind
north
winter
south
summer
note the jet streams
An estimate of the July mean zonal wind
north
summer
south
winter
note the jet streams
Let’s spend some time with the atmosphere.
Geostrophic wind 300 hPa
How does this example relate to global scales?
300 hPa
Geopotential contours at 300 hPa
Northern Hemisphere
September 17, 2008
Wind and geopotential 200 hPa
Note: Variability in east-west of the wind field.
Note: Troughs associated with mountain ranges, continents
Note: Time variability of the wind field.
Geopotential contours at 850 hPa
Northern Hemisphere
September 17, 2008
700 hPa
500 hPa
300 hPa
50 hPa
North-south / Winter-summer
DJF 500 hPa Average
JJA 500 hPa Average
Anomaly 100 hPa
23 October 2006, Geopotential Height
23 October 2006, Ozone
End: Pictures: Waves, Weather, and Climate