There are a few satellites in the atmospheric research which give measurements particular to one layer such as troposphere, stratosphere etc. How do they distinguish between different layers? The radiation that is reaching the sensor has to pass all the layers and there will be many absorption features with in the same spectral region. so, how we are able to get measurements like CO2 in troposphere or ozone in stratosphere?
There is a fair definition of distinguishing troposphere and stratosphere. The boundary between them is defined as tropopause height. Sometimes there are more than one tropopause height. For example; according to WMO:
1)The first tropopause is the lowest level at which the lapse rate decreases to 2Ckm-1 or less, provided also that the average lapse rate between this level and all higher levels within 2km does not exceed 2Ckm-1
2) When, above the first tropopause, the average lapse rate between any level and all higher levels within 1km exceeds 3Ckm-1, then a second tropopause can occur (can!) and is defined by the criteria of above definition. The tropopause can either be above or within 1km layer.
3) Further tropopause may be defined similarly.
Therefore as you can see it is not a fixed definition. The boundary is not obviously defined. It can change in respect to latitude and day of year.
So the first procedure you can implement is to retrieve temperature profile and use it in order to identify the boundary.
About ozone and the free-electrons, you can also get density profile and there is another boundary definition (F1,F2,E , ...). It completely differs from the electrically-neutral region.
Finally, from my point of view, you should first define exactly which variables you are willing to work on. Boundary layering is almost a field.
Dear Amirhossein, Thanks for commenting. Actually I wanted to know that how satellites differentiates between altitudes. Like in literature often we come across sciamachy tropospheric methane, GOME stratospheric ozone like that. How the satellite systems take it. Whether we will manipulate the data or satellites are designed in such a way so that they give measurements with in that altitude ( say upto 15 kms from surface and so..). Else is there any physical principle behind it so that the measurements will be limited to that particular altitude range.
Srinivasarao i guess it is more to do with chemical composition at different level rather than mere altimetry. But this is intresting, if you get an answer I will be intrested to know as well. Will keep following the replies you get from others.
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