insolation and temperature. electromagnetic radiation (emr) can be described as waves. note the...
Post on 22-Dec-2015
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Electromagnetic Radiation (EMR) can be described as waves.
Note the generation of a magnetic field at right angles to an electrical field and both are perpendicular to the direction of EMR propagation
http://micro.magnet.fsu.edu/primer/java/electromagnetic/index.html
The wavelength () of EMR is directly related to the amount of NRG in the radiation.
Short () (e.g. gamma rays) have a higher NRG content
Long () (e.g. thermal or microwave (Radio) have a lower NRG content
As the velocity of the propagation of EMR (the speed of light) is believed to be a constant (c)
The number of waves to pass a single point in a given period (the frequency, v) is much higher for shorter radiation
Atmospheric Windows
Some EMR passes through the atmosphere with no interference (an ‘atmospheric window’
Some EMR is absorbed (or blocked) by components in the atmosphere
The most significant absorbers of EMR in the atmosphere are O2 , N2, O3, CO2, H2O
Gamma radiation, X-rays, and UV radiation absorbed in the upper atmosphere
Water vapor and Carbon Dioxide absorb portions of the EM spectrum in the thermal portions of the spectrum
Atmospheric scattering: (skylight or haze)
Rayleigh scatter (molecular scatter) primary factor in upper atmosphere (why the sky is blue)
Mie scatter (non-molecular scattering, water/ice/salt/smoke) primarly in lower atmosphere
When the sun is at very low angles, virtually all the shorter EMR is scattered, allowing only the longer, lower NRG waves (reds) to pass through.
57.5 degrees North (same latitude as Moscow and Hudson’s Bay… semi-tropical gardens on the coast of Scotland
Temperature Inversion… warmer air slides over the cool air at the surface trapping the surface air beneath a very stable upper air mass