Some of the rest is interesyting in this post:
Adiabatic Lapse Rates
Types of lapse rates
There are two types of lapse rate:
Environmental lapse rate – which refers to the actual change of temperature with altitude for the stationary atmosphere (i.e. the temperature gradient)
The adiabatic lapse rates – which refer to the change in temperature of a parcel of air as it moves upwards (or downwards) without exchanging heat with its surroundings. The temperature change that occurs within the air parcel reflects the adjusting balance between potential energy and kinetic energy of the molecules of gas that comprise the moving air mass. There are two adiabatic rates: Dry adiabatic lapse rate
Moist (or saturated) adiabatic lapse rate
In "The Atmosphere" we discovered that air temperature usually decreases with an increase in elevation through the troposphere. The decrease in temperature with elevation is called the environmental lapse rate of temperature or normal lapse rate of temperature. Recall that the normal lapse rate of temperature is the average lapse rate of temperature of .65o C / 100 meters. The environmental lapse rate of temperature is the actual vertical change in temperature on any given day and can be greater or less than .65o C / 100 meters. Also recall that the decrease in temperature with height is caused by increasing distance from the source of energy that heats the air, the Earth's surface. Air is warmer near the surface because it's closer to its source of heat. The further away from the surface, the cooler the air will be. It's like standing next to a fire, the closer you are the warmer you'll feel. Temperature change caused by an exchange of heat between two bodies is called diabatic temperature change. There is another very important way to change the temperature of air called adiabatic temperature change.
Make sure you notice that we are talking about moving air (rising or subsiding), not still air. The change in temperature of still air (that is, air that is not rising or subsiding) follows the Environmental Lapse Rate, which varies considerably, but averages about 6.5 deg C/1000 meters (3.6 deg/1000 feet). In still air, if you went up in a hot air balloon, carrying a thermometer and taking the air temperature every 1000 meters, on average the temperature would drop 6.5 degrees C every 1000 meters. The rate of temperature change as you rise in still air is not as great as the rate of change of rising air; that is, the air parcel does not cool off as fast.
For instance, the air temperature at sea level is 28 degrees C. Climb into your balloon, release the tethers, and go up 1000 meters in the still air. On average, the air temperature 1000 meters up will be _21.5___degrees C. If the air were rising, and the temperature at sea level was 28 degrees C, what would the temperature of the air be after it rose 1000 meters? 18C
People talk of adiabatit lapse rates as if they control the atmosperic temperatre. Why?
These lapse rates refer to moving a number of molecules from low pressure to high pressure and getting heated. No problem with that. BUT
For every molecule moved down to high press ure there must be a molecule moved from high to low. It cannot be a one way transport (obviously!).
So, in my books, the heating effect of falling molecules equals the cooling effect of rising molecules. Hence no effect.
So Why is it colder up a mountain than on the plains.
GHG free air absorbs litle of the available sunlight. Air with GHGs absorbs only at the known absoption frequencies and the proportion of theses frequencies in the TSI is relatively small. There is therefore little air heating due to sunlight.
However sunlight hits the ground and 70% gets absorbed and reradiated as heat at long wave infra red frequencies. These will heat the air via absoption. There is more close ground creating warming in a valley than on a hill hence it will be warmer.
NOW if there is a 1000 metre plateau will this be as warm as the valley below - if not, why not?
The adiabatic lapse rate is defined by the "gas Laws" not by gravity (other than of course high gravity gives high pressure!).
The adiabatic lapse rate requires that a fixed number of molecules be moved between pressure differences. Once at a new pressure the new temperature will stabilise to the surroundings (but that is not what adiabatic lapse rate is about).
However, for every molecule transported from high to low pressure there MUST be a molecule transported from low to high pressure. This means there is NO net flow of energy.
Where the atmosphere blends into a vacuum there can be no convective/conductive transfer of energy (there is nothing to transfer the energy to!)
Radiation is the only option. N2 H2 O2 etc. have little propensity to absorb radiation. Hoever they will get warm by transfer of heat from GH gasses. All hot bodies emit radiation (bb radiation).
At the other end of the air column you have similar problems. The ground/sea warms through absorption of the shorter wavelengths of TSI (where most of the solar energy is). The heat is radiated from the ground/sea as LWIR and by contact at the boundary between earth and atmosphere. The heat must be transferred from molecule to molecule by contact or by convection. A slow process. Conduction will be enhanced by high pressure, convection will be slowed.
The radiated energy is NOT significantly absorbed by O2 N2 H2 etc. no matter what the pressure. Even a solid glass fibre can be made extremely low loss 0.2dB per km and the molecules are pretty solidly packed http://www.fiberoptics4sale.com/wordpress/optical-fiber-loss-and-attenuation/ . Without a GHG this radiation would escape without attenuation straight to space. GHGs will "absorb" this LWIR at certain frequencies and re-emit it in all directions.
Atmospheric longwave irradiance uncertainty: Pyrgeometers compared to an absolute sky-scanning radiometer, atmospheric emitted radiance interferometer, and radiative transfer model calculations.
Downward longwave irradiance uncertainty under arctic atmospheres: Measurements and modelinghttp://www.slf.ch/ueber/mitarbeiter/homepages/marty/publications/Marty2003_IPASRCII_JGR.pdf
Spectral and Broadband Longwave Downwelling Radiative Fluxes, Cloud Radiative
Forcing, and Fractional Cloud Cover over the South Polehttp://www.webpages.uidaho.edu/~vonw/pubs/TownEtAl_2005.pdf
Measurement of night time downward radiation
So we know the solar output received in the dark is 0We know that O2 and N2 have very very very little thermal radiation.
So where does all that downward radiation come from (at least 270W/sqm)
It can only be from GHGs.
During the day we receive about 380W/sqmSo the 270W/sqm is additional to the solar irradiance.
So the average night day temp difference is less than expected (no sideways conduction/wind required)
Do O2 N2 CO2 radiate
Cloud transmission (from above-FTIR looking down) from
An introduction to atmospheric radiation
By Kuo-Nan Liou
Transmission through the atmosphere. If GH effect exists then there should be mmissing parts of emission spectrum when looking at the earth. AND when looking up at the sky there should be higher levels of radiation at the same wavelengt as is missing when looking down. Is this the case? It seems so:
spectral plot is here:http://www.patarnott.com/atms749/powerpoint/ch6_GP.ppt
IR great plains measured here:
SGP Central Facility, Ponca City, OK
36° 36' 18.0" N, 97° 29' 6.0" W
Altitude: 320 meters
Better stuff here!!