DOI: 10.7280/d1096p
title: Solar-J and Cloud-J models version 7.6c

description: This dataset includes the models (fortran code, matlab code, data) used to
 simulate the heating and photolysis rates in a spherical
 atmosphere.  Both Solar-J v7.5 and Cloud-J v7.3c have been
 published previously, but with the publication of Prather and Hsu, "A
 round Earth for climate models" in PNAS (2019) both models have been
 merged in terms of overlapping subroutines and both now include option for
 (0) a flat-Earth atmosphere, (1) solar ray tracing through a spherical
 atmosphere, (2) refracted solar rays in a spherical atmosphere, and (3) a
 geometically expanding spherical atmosphere that includes the extra area,
 volumen and mass for a spherical hydrostatic atmosphere.  
 "Sunlight drives the Earth's weather, climate, chemistry and
 biosphere.  Recent efforts to improve solar heating codes in
 climate models focused on more accurate treatment of the absorption
 spectrum or fractional clouds.  A mostly forgotten assumption in
 climate models is that of a flat-Earth atmosphere.  Spherical
 atmospheres intercept 2.5 W m-2 more sunlight and heat the climate by an
 additional 1.5 W m-2 globally.  Such a systematic shift, being
 comparable to the radiative forcing change from preindustrial to present,
 is likely to produce a discernible climate shift that would alter a
 model's skill in simulating current climate.  Regional
 heating errors, particularly at high latitudes, are several times
 larger.  Unlike flat atmospheres, constituents in a spherical
 atmosphere, such as clouds and aerosols, alter the total amount of energy
 received by the Earth.  To calculate the net cooling of aerosols
 in a spherical framework, one must count the increases in both incident
 and reflected sunlight, thus reducing the aerosol effect by 10-14%
 relative to using just the increase in reflected.  Simple fixes
 to the current flat-earth climate models can correct much of this
 oversight, although some inconsistencies will remain." Early climate
 and weather models, constrained by computing resources, made numerical
 approximations on modeling the real world.  One process, the
 radiative transfer of sunlight through the atmosphere, has always been a
 costly component.  As computational ability expanded, these
 models added resolution, processes, and numerical methods to reduce errors
 and become the Earth system models that we use today.  While many
 of the original approximations have since been improved, one -- that the
 Earth's surface and atmosphere are flat – remains in current
 models.  Correcting from flat to spherical atmospheres leads to
 regionally differential solar heating at rates comparable to the climate
 forcing by greenhouse gases and aerosols.  In addition, spherical
 atmospheres change how we evaluate the aerosol direct radiative forcing.
 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 driver code is an example
 and must be modified extensively for 3D CTM/CCM use.  A corrected
 version 8.0c is posted under Dryad, Dataset,
 https://doi.org/10.7280/D1Q398. 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" and should be in parallel with Liquid Water
 Path [LWP] calculation.
description: This dataset includes two models that were coded and tested by
 Juno Hsu and Michael Prather (UC Irvine). Solar-J is the code version that
 can be implemented incliamte model to calculate soalr heating rates. 
 Cloud-J here is a stanalone code that can be integrated into a
 chemistry-transport model (CTM) or more encompassing earth system model
 (ESM).  Cloud-J is a superset of the Fast-J code that has been implemented
 in many CTMs.  The included meteorological datasets are meant to be
 replaced with the users own; the other data tables are based on underlying
 laboratory or atmospheric data or fundamental physics or previous model
 development.
description: Both Solar-J and Cloud-J modells included here should be able to
 run a standalone codes and reproduce the included output data.  The data
 and code are documented inline at some level, as well as inthe
 publications.