No, i need a thing like this

The required atmospheric absorption spectrum data can be found at the following link: http://www.spectralcalc.com/info/about.php

http://www.spectralcalc.com/info/about.php

Another suggested link with some datasets (.xls format) of atmospheric absorption spectrum is: http://cleanet.org/clean/community/activities/c4.html

I am not sure the source for this data!!! 

http://cleanet.org/clean/community/activities/c4.html

Try to find the absorption coefficients of the atmiospheric constituents (ozone, water vapour, CO2, methane...) in the Radiative Transfer Codes such as MODTRAN, LibRadTran, and many others. They are all similar and they all have the same problem: the absorption coefficients of aerosols are the lest well known.

Hitran databases (high-resolution transmission molecular absorption database)  is the one you want to use. And the code to calculate the transmission.

please take a look at: 

http://hitran.org/

hope it helps.

pubu

i've seen all the links but no one is the one i need...

Marco:

you need to do the calculations by yourself, it is pretty simple.  Unless someone has already generated Atmospheric Transmittance (which  depends on Atmospheric Profiles  you selected or inputted), and suit your needs..

pubu 

All repliers

This man can be much more polite

Instead of saying like a small child

I do't want THIS

I you are talking to me i was writing with my cell phone and didn't want to waste words. I am sorry this passed as unpolite, it wasn't my thought.

Marco

It is about your question and the effort repliers made to prpvide you with what you want

you should reread your own reponses

i thank everyone for their help and i'm glad that so many people replied, but if nobody has given me what i asked what should i say?

In the first i only specified what i needed replying the previous question, in the second reply i just said that nothing provided still helped me. I don't think to have replied in a bad way. Anyway, THANK YOU for your advice.

And extremely kind regards

Marco

Then make clear what you really need

in Hitran Modtran and Lowtran you can find tabulations

What then EXACTLY do YOU want/need

You got answers from world-experts in the field

i need a text file inside which there is a two column data (lambda and transmission or absorption %) of a typical atmospheric transmission or absorption. The lambda range has to start at least from 300 nm. Since i have no time to calculate it with the various softwares and i can't install them i only need this file instead of a plot. That's all...

What do you mean

THAT's ALL. You can easlity tranfer what ever  file to a textfile yourself. You think other people' s time is less valuable?

Only to clarify the things and then i'll quit this conversation because i don't want to quarrel and i don't have time to waste.

No one has obliged anyone to answer my question and who answered made it by his own. I only specified with THAT'S ALL that my request was simpler that what it seemed.

And i wanted to specify that if anyone has this file ready could give it to me and if they haven't it doesn't bother, i will make without it!sincerely i don't know why you continue woth this silly discussion. 

I am also searching the values of absorption cross section for various reactive species. For example, for hydroxyl radical it is 1.2 x 10^-16 cm^2 at 309 nm. Could someone help me with the absorption cross section of Nitric oxide with its wavelength ? Is there any way of calculation ?

Are you looking for actual instrumented measurement of atmospheric spectra?  If so, there are no easy answers to your question.  Indeed, I don't know of ANY simple/txt etc files of this sort.  However, you can (with a lot of work) get the satellite etc data, and then convert those file formats to whatever you like.

QUESTION:  are you looking for spectra of the radiation that:

1) Arrives from the Sun?

2) Arrives at the Earth's surface?

3) Is radiated from the Earth's surface as seen from space/satellites?

You may wish to start by getting a hold of this: "GEWEX Radiative Flux Assessment (RFA)" (i.e. http://www.wcrp-climate.org/ documents/GEWEX%20RFA-Volume% 201-report.pdf)

Some other sources are as reported by the WMO earlier this year are (and I quote):

"Surface Radiation Budget data (https://gewex-srb.larc.nasa.gov/common/php/SRB_data_products.php) are ready for a long term release and CERES (https://ceres.larc.nasa.gov/order_data.php) is updating to their Edition 4. There is also a MEASURES Project that will recalibrate and issue a new ERBE data set (https://science.larc.nasa.gov/erbe/). "

Once again, the datasets of instrumented measurements at those and other locations come in a somewhat complex data format since they represents many many sweeps by satellites from many locations and many angles etc etc.  I have written some code to "translate" some of those data files into something useful (e.g. to "load into a spreadsheets" etc), but my code is NOT ready for "prime time".