Hi again,
We were not aware of the first point, but this indeed look like an issue
of numerical precision.
We derive tau from transmissivity. I did a test in Matlab. exp(-740) is
> 0, while exp(-750) gives 0. This fits what you report reports, that
optical thicknesses above 750 can not be reconstructed from the
transmissivity, as it has become zero.
Bye,
Patrick
On 2021-09-21 17:12, Shaofei Wang wrote:
Dear ARTS developers:
My name is Shaofei Wang, a graduate student from China. I'm very
sorry for bothing you.
Recently, i am studying ARTS. I simulated the optical depth of
the standard tropical atmosphere under clear-sky with ARTS (10-1000GHz).
Please see the attachment (.png) for the simulation results.
But I encountered two problems:
(1) When odepth is greater than 750, inf appears in odepth. I
guess this is due to the calculation accuracy of C++, but i am not sure.
(2) When only H2O is used as absorbing species, the optical
depths is sometimes greater than those when using N2, O2 and water as
absorbing species. This is very confusing to me. In my opinion, the
optical depth of the latter should always be greater than or equal to
the former. I would like to ask if there is a problem with my
understanding or with my ARTS controlfile. Please see
the attachment (.arts) for the arts controlfile used.
I look forward to your reply to my email. Thank you again for
your contribution to ARTS!
Thanks in advance and Best Regards,
Shaofei Wang
从Windows 版邮件 <https://go.microsoft.com/fwlink/?LinkId=550986>发送
_______________________________________________
arts_users.mi mailing list
arts_users.mi@lists.uni-hamburg.de
https://mailman.rrz.uni-hamburg.de/mailman/listinfo/arts_users.mi
_______________________________________________
arts_users.mi mailing list
arts_users.mi@lists.uni-hamburg.de
https://mailman.rrz.uni-hamburg.de/mailman/listinfo/arts_users.mi