This is the Earth orbit model code as described in the following publication: Kostadinov, T. S. and Gilb, R.: Earth Orbit v2.1: a 3-D visualization and analysis model of Earth's orbit, Milankovitch cycles and insolation, Geosci. Model Dev., 7, 1051-1068, doi:10.5194/gmd-7-1051-2014, 2014. The code posted here is the same as the code in the Supplement to this publication (http://www.geosci-model-dev.net/7/1051/2014/gmd-7-1051-2014-supplement.zip), with the exception of a minor fix to Earth_orbit_v2_1.m to correct a plot clipping issue. For instructions of use, refer to the publication cited above and the original ReadMe.txt file (contents given here immediately below). Original ReadMe.txt file: --> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +++++ Earth Orbit Model v2.1 Discalimer, License and Instructions for Use +++++++ +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +++++ Authors: Dr. Tihomir Sabinov Kostadinov and Roy Gilb ++++++++ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ (c) Dr. Tihomir Kostadiov and Roy Gilb University of Richmond University of California Santa Barbara //Author Contact Information: Department of Geography and the Environment 28 Westhampton Way University of Richmond Richmond, VA 23173 USA E-mail: tkostadi@richmond.edu +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Reference: When available, consult the final revised version of: T. S. Kostadinov and R. Gilb (2013), Earth Orbit v2.1: a 3-D visualization and analysis model of Earth’s orbit, Milankovitch cycles and insolation, Geosci. Model Dev. Discuss., 6, 5947-5980, 2013, www.geosci-model-dev-discuss.net/6/5947/2013/ doi:10.5194/gmdd-6-5947-2013 ++++++++++++++++++++++++++++++++++++++++ +++++ Disclaimer & License ++++++++++++ ++++++++++++++++++++++++++++++++++++++++ (c) Tihomir Kostadinov & Roy Gilb, 2006-2014 University of Richmond, VA, USA University of California Santa Barbara, CA, USA ***Disclaimer: This software is supplied "as is". No warranty is given, express or impllied, of fitness for any purpose. Under no circumstances shall the authors or their instituions be liable to anyone for direct, indirect, incidental, consequential, special, exemplary, or any other kind of damages (however caused and on any theory of liability, and including damages incurred by third parties), arising from or relating to this software, or user's use, inability to use, or misuse of the software, or errors of the software. This software is not guaranteed to be error-free and is not meant to be used in any mission-critical applications. Use at your own risk and verify with other sources when appropriate. *** License: Unless superceding rules of the author's institutions apply, this software is free to use, distribute and modify for non-commercial purposes under the Creative Commons BY-NC-SA 3.0 license. Authors should be notified at <tkostadi@richmond.edu> if any modified copies are to be distributed to third parties. Any such modifications must be clearly documented and stated properly. ++++++++++++++++++++++++++++++++++++++++ +++++ Installation Instructions +++++ ++++++++++++++++++++++++++++++++++++++++ There is no installation per-se required. You need to have MATLAB(r) installed on your system. Download file Earth_Orbit_v2_1.zip and unzip its contents into a folder of your choice. Either add the path to this folder to the MATLAB(r) path or set the current working directory to that folder. In order to run the model, type the following at the MATLAB(r) command prompt: >> Earth_orbit_v2_1 and press Enter. This should bring up the GUI with all the user controls. These are fairly intuitive and self-explanatory. Brief help is provided below. For details, refer to the publication referenced above. If surface plots do not render properly, you may need to change the renderer used by MATLAB(r). At the prompt, type: >> set(gcf,'renderer','r_name') where r_name can be opengl, painters or zbuffer. This will change the renderer for the current figure. Note: If the GUI window is not sized properly for your system/monitor configuration (should be rare), you can change the window size (e.g. maximize it). If that does not work, you may need to use the "guide" tool in MATLAB(r) to resize/rearrange the GUI figure and resave it. At the prompt, type >> guide Earth_orbit_v2_1 ++++++++++++++++++++++++++++++++++++++++ +++++ Brief Model Use Help +++++++++++ ++++++++++++++++++++++++++++++++++++++++ Pressing the Help Button in the GUI should open this file in the MATLAB editor or another editor of your choice. For details, refer to the publication referenced above. (1) Initial Constants and Options: Choose a real astronomical solution or the demo mode (user-selected Milankovitch parameters) (2) Milankovitch Orbital Parameters: Select year since J2000 or values for the orbital parameters, depending on chosen mode. (3) Calendar/Date, Latitude and Insolation Options: Select month and date, latitude (Southern hemisphere latitudes are negative), the TSI(S_o) value, as well as the calendar start date - either equinox is fixed to be March 20, or perihelion is fixed to be January 3. Press the "Plot/Update Orbit" button to produce/update a 3D orbital configuration plot using the currently chosen input parameters, as well as update the text output in the GUI. (4) Time Series (TS) and Insolation Plotting Options: Depending on selected mode, various time series plots can be produced as indicated on each button. The plot(s) can be produced if the button is active. For the astronomical solutions modes, users need to select the range of years to plot. Check the corresponding box if you wish to save the plot data as ASCII files for further analysis. (5) Outputs: Numerical outputs update when the "Plot/Update Orbit button is pressed. Summary of the Contents of Earth_Orbit_v2_1.zip: -------------------------------------------------------------------------------- FileName Explanation -------------------------------------------------------------------------------- ReadMe.txt This file Earth_orbit_v2_1.m Main matlab m-file that needs to be called to run the model; spawns the main GUI control window Earth_orbit_v2_1.fig GUI figure associated with the above. Useful if user wished to modify the GUI. orbit.m Main function thet calculates and plots orbital position keplerian.m Solves forwardf Keplerian problem keplerian_inverse.m Solves inverse Keplerian problem insolation.m Calculates insolation insol_3d.m Calculates spatio-temporal distribution of insolation for a single year insol_TS.m Calculates insolation time series as a function of year since J2000 and latitude generate_rot_m.m Helper function to calculare rotation matrix for orbital geometry computation Berger_orbpar.m Calculates the Milankovitch parameters according to the Berger 1978 solution getLaskar.m Read in and parse Laskar et al. (2004) Milankovitch parameter solution orbit_output Directory in which numerical model output is saved. Examples are provided. INSOLP.LA2004.BTL.ASC File provided by Jacques Laskar, see below for details INSOLN.LA2004.BTL.100.ASC File provided by Jacques Laskar, see below for details Berger_data.dat Contains output from Berger_orbpar.m EPICA_CO2.dat EPICA CO2 time series, see file header for details. EPICA_deuterium.dat EPICA deuterium/temperature time series, see file header for details. LR04_dO18_benthic_stack.dat The Lisiecki and Raymo (2005) benthic delta-O-18 stack, see file header for details. Zachos01_d18O.dat The Zachos et al. (2001) benthic delta-O-18 complitaion, see file header for details. contemp_insol.dat J2000 insolation pattern for the Laskar et al. (2004) solution and using S_o = 1,366 W m^-2 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +++++ ReadMe for the input files provided by Dr. Jacques Laskar: ++++ +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ The following is an excerpt from the Readme.txt located at : http://www.imcce.fr/Equipes/ASD/insola/earth/La2004/README.TXT accessed August 1, 2013 This file, provided by Dr. Jacques Laskar at IMCCE, France, describes the contents of the following two ASCII files, used without modification by the Earth Orbit model: Filenames: INSOLN.LA2004.BTL.100.ASC INSOLP.LA2004.BTL.ASC These files are courtesy of Dr. Jacques Laskar and are available at: https://www.imcce.fr/Equipes/ASD/insola/earth/La2004/index.html The files were downloaded from the above link on July 16, 2012 The main website for the paleoclimate astronomical solutions of Dr. Jacques Laskar is at http://www.imcce.fr/Equipes/ASD/insola/earth/earth.html =========================== ============================ ASTRONOMIE ET SYSTEMES DYNAMIQUES INSTITUT DE MECANIQUE CELESTE la2004 2010, January 18 =========================== ============================ La2004 : ========== ******************************************************************************** * Authors: J. Laskar, M. Gastineau, F. Joutel * * (c) Astronomie et Systemes Dynamiques, Institut de Mecanique Celeste, * * Paris (2004) * * * * Jacques Laskar * * Astronomie et Systemes Dynamiques, * * Institut de Mecanique Celeste * * 77 av. Denfert-Rochereau * * 75014 Paris * * email: laskar@imcce.fr * * * ******************************************************************************** CONTAINS: ========= -------------------------------------------------------------------------------- FileName Explanations -------------------------------------------------------------------------------- INSOLP.LA2004.BTL.ASC Nominal solution La2004 after present years (0 to +21Myr) INSOLN.LA2004.BTL.100.ASC Nominal solution La2004, before present years (-101Myr to 0) Byte-per-byte Description of file: INSOLN.LA2004.BTL.ASC Byte-per-byte Description of file: INSOLP.LA2004.BTL.ASC -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1-14 F13.3 1000yr t Time from J2000 in 1000 years 18-39 D25.16 --- e eccentricity 43-64 D25.16 rad eps obliquity (radians) 68-89 D25.16 rad pibar longitude of perihelion from moving equinox (radians) -------------------------------------------------------------------------------- Byte-per-byte Description of file: INSOLN.LA2004.BTL.100.ASC Byte-per-byte Description of file: INSOLN.LA2004.BTL.250.ASC -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1-9 F8.0 1000yr t Time from J2000 in 1000 years 10-18 D9.6 --- e eccentricity 19-27 D9.6 rad eps obliquity (radians) 28-37 D10.6 rad pibar longitude of perihelion from moving equinox (radians) -------------------------------------------------------------------------------- Description: La2004 is the nominal solution for precessional quantities and orbital quantities of the Earth. The solution La2004 is provided with fortran subroutine in order to compute the insolation quantities of Earth. BIBLIOGRAPHY: ============ La90: Laskar, J.: 1990, The chaotic motion of the solar system. A numerical estimate of the chaotic zones Icarus, 88, 266 La93: Laskar, J., Joutel, F., Boudin, F.: 1993, Orbital, precessional and insolation quantities for the Earth from -20 Myr to + 10Myr Astron. Astrophys. 270, 522 La2004 :Laskar, J., Gastineau, M., Joutel, F., Robutel, P., Levrard, B., Correia, A., A long term numerical solution for the insolation quantities of Earth. {\it in preparation} ================================================================================