Dear Colleagues, you receive this eMail because you are either a user of the radiative transfer package libRadtran or because we think that you might be interested in this information. Should you not be interested in receiving further information, please let us know. Should you know of anybody who might be interested in libRadtran and whose name is not on the distribution list, please let us also know as well. Attached to this eMail is the fifth libRadtran Newsletter. The main issue of this Newsletter is to announce the new version, *** libRadtran 1.01 *** which includes some bug fixes and minor improvements of version 1.0. And now, we wish you all a happy and successful new year! Bernhard Mayer and Arve Kylling. ------------------------------------------------------------------ Dr. Bernhard Mayer Bernhard.Mayer_at_dlr.de Deutsches Zentrum fuer Luft- und Raumfahrt (DLR) Institut fuer Physik der Atmosphaere, Oberpfaffenhofen, D-82234 Wessling, Germany. Phone: +49 8153 282568, Fax: +49 8153 281841, Homepage: http://www.bmayer.de ------------------------------------------------------------------ /*---------------------------------------------------------------- * libRadtran Newsletter No. 5 * * December 24, 2004 * * Bernhard Mayer (bernhard.mayer_at_dlr.de) * Arve Kylling (arve.kylling_at_helse-sunnmore.no) * * ### More info: http://www.libradtran.org ### *----------------------------------------------------------------*/ Welcome to the fifth libRadtran Newsletter! Dear libRadtran users, it is Christmas again, and following a long tradition, a new version of libRadtran has been released today, 1.01. The change in the version number is small, and so is the change in the model. No new options have been added, but a few bugs and inconsistencies have been fixed. One of those was that libRadtran 1.0 did not compile under Windows XP (as we did not have a Windows XP to test the model at the time of the last release). In the last newsletter we also promised a libRadtran paper. The 22 page paper has been submitted to ACPD exactly a month ago (November 24) and we will let you know immediately when (if) the publication is accepted for ACPD which should happen late January / early February. At the libRadtran web page we have collected 45 publications which reference libRadtran. Whenever you use libRadtran in a publication we would be happy to include the reference in this list. And now for the changes from version 1.0 to 1.01: Bug fixes: * Version 1.0 did not run under Windows XP. Fixed the problem. * This one was not likely to happen, but if it happened it caused serious errors: "configure" checks if the netcdf library is available; if it is not available, the "correlated_k KATO" option is disabled. However, we forgot to also disable KATO2, and if one ran libRadtran with "correlated_k KATO" without having netcdf installed, the results were seriously wrong: For all wavelengths with more than one sub-band in the k-distribution "0" was returned. If one only looked at the integrated solar flux ("output sum"), the integrated solar radiation could be off by a factor of 2. If the spectrum was output, the problem was clearly visible because all radiation quantities in the affected wavelengths were "0". Fixed the problem. Thanks to Manfred Wendisch who found the bug! * Fixed a bug in the Cox and Munk sea surface BRDF which caused problems in the liquid water absorption bands in the near IR. The code was adopted from the 6S model. Paul Richiazzi pointed out that the original 6S code has a bug which shows whenever water absorption is not zero, in particular in the liquid water absorption bands 2.5 micron and higher; for lower wavelengths the effect is small. We confirmed that following Born and Wolf, Principles of Optics 7th Edition. This bug usually caused disort2 to crash because the albedo quickly reached values larger than 1 in this case which is checked by disort2. Smaller changes: * disort2 does now provide azimutally averaged intensities * Some small changes which make uvspec more Fortran77-compliant (e.g. replaced ">" by ".GT.", split data statements if more than 25 continuation lines); suggestions by Alessandro Ipe, October 4, 2004. * More consistent checks if the ice particle radii are within the ranges valid for the different ice cloud parameterizations. * Replaced "correlated_k SBDART" by "correlated_k LOWTRAN" because that's what it actually is! The user, however, is still asked to reference SBDART because that's where the code comes from. The old syntax, "correlated_k LOWTRAN" does still work but is not documented anymore. * Replaced "ic_properties yang" by "ic_properties key" because that's what it actually is! The old syntax, "ic_properties yang" does still work but is not documented anymore. * Introduced some extras to make uvspec more Mars-compatible, including CO2 absorption in the UV; O2 absorption is also included but the Schumann-Runge bands around 200nm, however, are not yet adequately represented. The latest version is available at http://www.libradtran.org, as usual. And now, have fun! Bernhard Mayer (bernhard.mayer_at_dlr.de) Arve Kylling (arve.kylling_at_helse-sunnmore.no)