karine.md.in (4647B)
1 # Karine 2 3 This code performs radiative transfer computations in the LW spectral 4 region, for a absorbing, emitting and scattering atmosphere. 5 `karine` uses the k-distribution spectral model (and the CK hypothesis 6 for inhomogeneities). 7 Radiative transfer results that are computed are: fluxes (upward, 8 downward, net), the radiative budget (average per layer) and its 9 gas-gas, gas-ground and gas-space components, and the Net Exchange Rate 10 matrix. 11 All results are provided for each spectral interval the input data is 12 defined for, and is also spectrally integrated. 13 14 ## Physical model 15 16 The inhomogeneous atmosphere is represented as a succession of 17 homogeneous slabs. 18 The temperature profile is taken as linear between layers centres. 19 In each layer, absorption and scattering properties must be provided for 20 the gas mixture (k-distribution data set), for a water cloud, and for 21 aerosols. 22 Reflection by the ground is taken into account. 23 24 ## Numerical method 25 26 Karine is based on a Monte-Carlo algorithm. 27 In addition to the possibility to take into account scattering, this 28 method has the advantage to compute a statistical uncertainty over each 29 result; this uncertainty can be interpreted in terms of a numerical 30 error. 31 In this respect, the Monte-Carlo method is considered as a reference 32 method: the numerical uncertainty can be lowered as much as necessary by 33 increasing the number of realisations. 34 35 ## Net Exchange Formalism 36 37 The Monte-Carlo algorithm consists in computing the Net Exchange Rate 38 between each couple (i,j) of atmospheric layers (+ ground and space). 39 See figures for examples. 40 This formalism provides a graphical representation of all radiative net 41 exchanges in the atmospheres: dominant and non-dominant terms can be 42 immediately identified, for any given spectral interval. 43 44 [](images/pne_mls_cs.svg) 45 46 > Matrix of Net Exchange Rates, spectrally integrated over the LW 47 > interval (4-100 micrometers) for a standard clear-sky Mid-Latitude 48 > Summer atmospheric profile. 49 50 51 [](images/pne_mls_ac.svg) 52 53 > Matrix of Net Exchange Rates, spectrally integrated over the LW 54 > interval (4-100 micrometers) for a standard Mid-Latitude Summer 55 > atmospheric profile, in the presence of three water clouds. 56 57 [](images/venus_ner.svg) 58 59 > Matrix of Net Exchange Rates, spectrally integrated over the LW 60 > interval (1.71-250 micrometers) for the Venus atmosphere. 61 62 ## Quick start 63 64 Karine @VERSION@: 65 66 - Sources: [tarball](downloads/karine@VERSION@.tgz) / 67 [pgp](downloads/karine@VERSION@.tgz.sig) 68 - Manual: [pdf](downloads/karine@VERSION@_manual.pdf) 69 70 ### Prerequisites 71 72 Only a fortran compiler is needed (no external libraries). 73 The `gfortran` compiler has been used for development. 74 75 76 ### Installation 77 78 Download and uncompress the `.tgz` archive. 79 Then you can try to compile the `karine` executable: go to the main 80 karine directory, then use the `make all` command to compile. 81 The most common sources of failure can be fixed by editing the 82 `Makefile` file in order to check compilation options (and more 83 specifically options related to the target architecture and 84 optimisations). 85 Whenever you modify a source file, you can re-compile using the `make 86 all` command. 87 But in the case you have to modify a include file, you will have to 88 erase all existing object files first using the `make clean` command, 89 before recompiling from scratch using the `make all` command again. 90 91 ## Usage 92 93 Please refer to the documentation in order to produce the 94 `/data/atmos_data.txt` input data file required by karine. 95 A example program (`make_data`) is provided in the `/data` directory: 96 use the `f0` script in order to compile it, but this program will only 97 produce a dummy data set (not a physical configuration). 98 The user has the possibility to set many options and input data by 99 editing the `options.in` and `data.in` input data files. 100 Please refer to the documentation for a description of the content of 101 these files. 102 103 ## License 104 105 Copyright © 2014-2018 |Méso|Star> 106 ([contact@meso-star.com](mailto:contact@meso-star.com)) 107 Copyright © 2008-2014 Centre National de la Recherche Scientifique (CNRS) 108 Copyright © 2008-2014 Institut Mines-Télécom Albi-Carmaux 109 Copyright © 2008-2014 Université Paul Sabatier 110 111 112 Karine is free software released under the GPLv2+ license: GNU GPL 113 version 2 or later. 114 You can freely study, modify or extend it. You are also welcome to 115 redistribute it under certain conditions; 116 refer to the 117 [license](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html) for 118 details.