{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Basic Radiative Transfer Calculation\n", "\n", "In this example we will calculate radiances from 340 nm to 700 nm in 1 nm steps using SASKTRAN-Disco. The geometry will be configured to be TEMPO looking at the ARG office on June 2 2017 at 3:14 PM and the atmosphere will be configured to consider Rayleigh scattering, O3, and NO2." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "%matplotlib inline" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "import sasktran as sk\n", "import sasktran.disco.interface as do\n", "import numpy as np\n", "import matplotlib.pyplot as plt" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "First we need to configure our sk.Geometry object. This object specifies the\n", "line of sight vectors as well as the solar position (based on mean mjd)." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "geometry = sk.NadirGeometry()\n", "\n", "# make the look vector from TEMPO to the ARG office\n", "tempo = sk.Geodetic()\n", "tempo.from_lat_lon_alt(0, -100, 35786000)\n", "geometry.from_lat_lon(\n", " lats=52.131638, \n", " lons=-106.633873,\n", " elevations=0,\n", " mjd=57906.843, \n", " observer=tempo\n", ")" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Next we need to configure our sk.Atmosphere object. This object specifies all\n", "atmospheric and surface properties to the engine." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "atmosphere = sk.Atmosphere()\n", "\n", "# add our species\n", "atmosphere['rayleigh'] = sk.Species(sk.Rayleigh(), sk.MSIS90())\n", "atmosphere['o3'] = sk.Species(sk.O3OSIRISRes(), sk.Labow())\n", "atmosphere['no2'] = sk.Species(sk.NO2OSIRISRes(), sk.Pratmo())\n", "atmosphere.atmospheric_state = sk.MSIS90()\n", "\n", "# add our surface properties\n", "atmosphere.brdf = sk.Kokhanovsky()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "We are now ready to perform the radiance calculation. Note that the engine can\n", "be default constructed (with properties set after construction), or the\n", "properties can be passed to the constructor." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "wavelengths = np.linspace(340,700, 361)\n", "engine = do.EngineDO(geometry=geometry, atmosphere=atmosphere, wavelengths=wavelengths)\n", "rad = engine.calculate_radiance()" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "scrolled": true }, "outputs": [], "source": [ "# Make plot\n", "plt.figure()\n", "plt.plot(rad['wavelength'], rad['radiance'])\n", "plt.xlabel('Wavelength [nm]')\n", "plt.ylabel('Sun Normalized Radiance [/ster]')\n", "plt.show()" ] } ], "metadata": { "kernelspec": { "display_name": "Python 3 (ipykernel)", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.8.13" } }, "nbformat": 4, "nbformat_minor": 2 }