Water vapor and solar zenith angle dependent absorption tables and radiance calculations
Data files
Feb 19, 2026 version files 6.89 GB
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era.99.tpw
25.80 KB
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era99_t_s_tape7_files.tar.gz
6.89 GB
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README.md
3.47 KB
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revised_depth_fracs_tcwv_sza.txt
8.79 KB
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revised_morel_fracs_tcwv_sza.txt
7.23 KB
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segelstein81_nm_1overE(cm).txt
18.06 KB
Abstract
The dataset has been generated in order to simulate the impact of atmospheric water vapor and solar zenith angle on the in-water heating profile. The 1 cm-1 resolution calculations are convolved with high-resolution in-water absorption from Segelstein (1981) in order to calculate the effect of shifting absorption weightings due to atmospheric water vapor. These values are then integrated over 9 discrete spectral bands that match those of the widely used Paulson & Simpson (1981) scheme, partitioned in terms of total column atmospheric water vapor and solar zenith angle. The end results are described in the GRL manuscript.
https://doi.org/10.5061/dryad.4qrfj6qhj
Modtran calculations of surface solar irradiance at 1 cm-1 resolution (500 - 40,000 cm-1) for 1,358 globally representative ocean atmospheres sampled from ERA-40. Various angles are simulated, corresponding to sec(solar_zenith_angle) values of 1, 1.5, 2, 3, 5 & 10 (approximately 0, 48, 60, 70, 78 & 84 degrees).
Description of the data and file structure
Format of files
The 9-band solar zenith angle dependent tables for solar Planck weight and in-water absorption are in revised_morel_fracs_tcwv_sza.txt and revised_depth_fracs_tcwv_sza.txt respectively.
The tables are organized by increasing solar zenith angle, with '00' being the Sun overhead. The other number is sec(sza) and is the exact quantity (the solar zenith angle is only quoted to the nearest degree).
The organization of each individual table is as follows:
<mean(TCWV(1))> <#profiles(1)> <band(1)> <band_2(1)> <band_3(1)> <band_4(1)> <band_5(1)> <band_6(1)> <band_7(1)> <band_8(1)> <band_9(1)> <sum(band1(1):band9(1))>
<mean(TCWV(2))> <#_profiles(2)> <band_1(2)> <band_2(2)> <band_3(2)> <band_4(2)> <band_5(2)> <band_6(2)> <band_7(2)> <band_8(2)> <band_9(2)> <sum(band1(2):band9(2))>
.
.
.
<mean(TCWV(13))> <#_profiles(13)> <band_1(13)> <band_2(13)> <band_3(13)> <band_4(13)> <band_5(13)> <band_6(13)> <band_7(13)> <band_8(13)> <band_9(13)> <sum(band_1(13):band_9(13))>
where band_i(j) is the data for band_i of the 9-band model for the corresponding mean TCWV amount mean(TCWV(j)) in kg.m-2. For the solar Planck weights, the data values are the fraction of the net solar radiation at the water surface and therefore will sum to unity (last column). The in-water absorption values are 1/e depths in meters, with the shortest wavelength band (band_1) being ~27 meters and all but one of the rest being <<1 meter, thus the sum is a somewhat arbitrary value between ~27 m and ~30 m. Note that the in-water absorption values in these tables have not yet been scaled to account for refraction - that adjustment is done inside the diurnal warming model code.
Modtran output files (1,358 profiles x 6 angles) are contained in a single tar file era99_t_s_tape7_files.tar.gz. Once extracted, the .tp7 output files are in standard "TAPE7" ASCII format. Output is 1 cm-1 resolution (columns are labeled in the ASCII file). File names are constructed as
era99_
where
The corresponding total column water vapor amounts for each of the 1,358 profiles is contained in era.99.tpw
The Segelstein high-resolution in-water absorption data are contained in ASCII file segelstein81_nm_1overE(cm).txt and contains values for the wavelength in nanometers and the 1/e depth in centimeters.
Sharing/Access information
Input atmospheric data was derived/sampled from the following sources:
Code/Software
MODTRAN4 uses "TAPE5" input files. Summary information of the input cards showing the model configuration for each run is provided in the first part of the *.tp7 output files. N.B. The latest version of Modtran is MODTRAN6 http://modtran.spectral.com/
The dataset has been generated using a globally representative set of 1,358 atmospheric profiles sampled from ERA-40 input to MODTRAN4 run at 1 cm-1 resolution, with a wavenumber range of 500 - 40,000 cm-1. Details are given in the README file.