This new data set (Cloud-J v8.0) includes near-UV cross sections for water vapor absoprtion that can be used to calculate photolysis rates in atmospheric chemistry models using the new photolysis code UCI Cloud-J version 8.0.  This data set and the code that uses it are updated and improved versions of the last published version 7.6c (Prather, Michael; Hsu, Juno, 2019, Solar-J and Cloud-J models version 7.6c, Dryad, Dataset, https://doi.org/10.7280/D1096P).  It cleans up some minor bugs (see notes) and now includes the option for water vapor absorption in the ultraviolet region 290-340 nm.  The new H₂O cross sections are derived from Pei et al. (2019, Water vapor near‐UV absorption: Laboratory spectrum, field evidence, and atmospheric impacts. JGR-Atmos, 124, 14,310–14,324. doi: 10.1029/2019JD030724).  With these new H2O cross sections, more solar UV is absorbed in the lower atmomsphere and many major photolysis rates are reduced by 10% near the surface.  We estimate that the lifetime of methane will increase by 7%.   

Note (30 May 2023).  An error in the calculation of Ice Water Path [IWP(L)] in the standalone driver code for Cloud-J versions 7.6 through 8.0 has been discovered.  This does not affect any of the results or example output archived here because the calculations of with and without UV H2O absorption were done with clear skies.  A corrected version 8.0c is posted. The corrected code line goes from "IWP(L) = 1000.d0*WIC(L)*PDEL*G100 / CLF(L)" to "IWP(L) = 1000.d0*WIC(L)*PDEL*G100"

The dataset was taken directly from the Pei et al. 2019 published tables and then re-mapped onto the Cloud-J wavelength bins.

The primary dataset (FJX_spec.dat) can be opened and read with any editor.  The use of this data to calculate photolysis rates (J-values) requires the Cloud-J v8.0 FORTRAN F90 source code and a FORTRAN compiler.  No special libraries are needed. A standalone version of the code and necessary data tables are provided in the Zenodo software archive linked to this Dryad data DOI.