Dear Ankit,

It looks like you are asking multiple questions at once: you mention two different atmospheric constituents (aerosols and CO2 concentrations) and two processes (increases in solar zenith angle and wind speed), and then ask whether there are any correlations, without mentioning any context or purpose for your questions. Let's separate these issues...

1. If you are wondering whether the concentration of aerosols in the atmosphere depends on the solar zenith angle, the answer is clearly no in general: the mobilization of aerosol particles and the atmospheric aerosol load do not directly change with the position of the Sun (or with the direction of observation, for that matter).

2. However, wind speed at or very near the land surface (or the ocean) may mobilize aerosols (or sea salt) if the surface is erodible and contains ample supplies of fine particulate materials (water droplets). Indeed, dust storms are created by strong surface winds that lift huge quantities of dust into the atmosphere.

3. If you are asking whether the observable Atmospheric Optical Depth (AOD) of an aerosol layer depends on the zenith angle, then the answer is yes, as far as the observation is concerned:

For a given weather situation, the atmosphere can generally be considered as a layered medium: the spatial variability in the vertical direction is much larger than in any horizontal direction (latitude or longitude). Consider one such layer where the concentrations of gases and particulate matter can be considered homogeneous. When such a layer is illuminated by the Sun, or observed from the ground (looking up) or from space (looking down), the effective thickness of the layer (with respect to processes of reflection, transmission or absorption) depends on the zenith angle of illumination or observation: the more it departs from the normal to the layer, the thicker the layer. Compare these two diagrams where the 'horizontal' bars represent the top and bottom boundaries of the layer and the 'vertical' or slanted bars represent the direction of illumination or observation:

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and

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The path length through the layer increases as (1/cos theta) where theta is the zenith angle, i.e., the angle between the normal to the layer and the direction of (illumination or) observation.

4. These arguments are also applicable to CO2: The concentration of carbon dioxide in the atmosphere does not depend on whether it is illuminated by the Sun or observed by anyone under any particular direction. However, if you do measure the amount of CO2 in an atmospheric layer, then please note that the quantity measured will vary with the angle of observation according to the diagram above, though we may also need to discuss the workings of the instrument and the exact measurement protocol...

5. Lastly, CO2 is a well-mixed gas in the lower atmosphere (up to about 100 km altitude: see http://ruc.noaa.gov/AMB_Publications_bj/2009%20Schlatter_Atmospheric%20Composition%20and%20Vertical%20Structure_eae319MS-1.pdf) because of the prevalence of turbulence. Wind does contribute to turbulence, of course, but the only places where you might find larger (or lower) CO2 concentrations than average would be very close to sources (and sinks) of CO2, i.e., inside a plant canopy of near a combustion system (breathing organism, car exhaust pipe, house or power plant chimney, etc.)

Cheers, Michel.

Thank you Michel sir for spending your valuable time and this Good answer for me.

more on CO2 trend and seasonal/latitudinal variation can be found here:

http://co2now.org/Current-CO2/CO2-Trend/seasonal-fluctuation-of-atmospheric-co2.html - the GIF-animation is worth a 1000 words (note the changes in the Northern hemisphere).

Regarding the CO2 vertical structure: you may also check Fig. 18 and 19 of this article:

Article Simultaneous retrieval of T(p) and CO2 VMR from two-channel ...