Even though the input file for your two runs look the same, the aren't the same run. The reason is that when you select RADTRAN, it calculates on the fly the irradiances based on parameters such as the day of year (for earth-sun distance), latitude, longitude, and atmospheric parameters (including ozone, atmos type, water vapor content, etc). In H42 those parameters are read from gcirrad.dat (written to the file by the UI). When you select RADTRAN as your atmosphere option, the input line that has the filename "..data/irradata.txt" is never used.
However, when you select the data file option, none of those parameters are used, no model is called -- the code simply reads the values from the data file and sets the downwellign Irradiance just above the surface to the values in the file.
It is purely coincidence that the two runs even have similar surface Eds -- it just means that the conditions you put into RADTRAN were similar to the ones when the irradata.txt file was generated.
Regards,
Lydia
On Jul 5, 2007, at 10:46 PM, Servet Ahmet Cizmeli wrote:
Hi everybody,
I would like to use the spectral downwelling irradiance measurements we performed above water surface instead of the Radtran sky model. With the GUI (H42), I created two runs:
1. a run that uses the option RADTRAN 2. a second run that is exactly similar to the first one except that it uses the option "USER-SUPPLIED DATA FILE" (E:\H42\data\irradata.txt)
When I compare the two Input files associated with these two runs, I see that they are exactly the same (except the first-two lines).
To my understanding, the two runs should create output files that would exactly be the same... However in the output files, Ed above surface are slightly different...
Am I missing something here? What is the parameter in the Input file that makes Hydrolight use the sky model we want and to what RECORD GROUP it does belong? I need to perfectly understand how it works as I am building an automated system that will bypass the GUI and modify the Input file for each run.
Hi everybody, I would like to use the spectral downwelling irradiance measurements we performed above water surface instead of the Radtran sky model. With the...
Servet (and all), Even though the input file for your two runs look the same, the aren't the same run. The reason is that when you select RADTRAN, it ...
Servet and everyone, In Hydrolight (HL), not everything is controlled by the input file. Some parameters are specified in the input file. Some are specified in...
Folks, Marcos is correct that modifying runs outside of the UI is a task that requires a lot of courage and should not be done cavalierly. I also wanted to add...
I understand it much better now, especially after Marcos' comments. Thanks Marcos, thanks Lydia. One more question: Looking at my newly compiled incfiles.for,...
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Servet, ... Note that the above steps do not perform a compilation. They merely consist of editing files. Really, I need to add a few steps: First, you should...
Hi Marcos, Thanks a lot for your precious comments. I'll try to write a fortran routine that will read the diffuse spectral irradiance along with Edtot. best ...
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Hi Zhiquang You can always compile the source code under Linux. I succeeded under Linux with the (commercial) Intel fortran compiler. But this means that you...
Hello Zhiqiang, Are you sure you don't want to run HL through "wine" in Linux and avoid compiling? It's very easy. First install "wine". Then using the GUI, in...
Hi Zhiqiang, Just in case you might want to run the HL DOS executable in Linux through wine, I figured out that you don't need to create a FAT32 partition. Now...
Hi Zhiqiang and Servet, I have installed HL in a FAT32 partition and used the HL executable and the GUI through Wine. I had to install the MSVBVM60.dll and ...
Hi Elena, As I wrote in my message, I did not pursue the challenge of running the GUI through Wine because I did not really need it. However I am pretty sure...
I understand it much better now, especially after Marcos' comments. Thanks Marcos, thanks Lydia. One more question: Looking at my newly compiled incfiles.for,...
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