A Global Atmospheric Methane Record from a Tropical Ice Core (In Review)

This repository archives the necessary data to recreate Figure 1 as well as run the four-box model to calculate the methane source strengths and plot Figure 2 as presented in A Global and Regional Atmospheric Methane Record from a Tropical Ice Core" (Lamantia et al., in review). The code drives a Monte Carlo simulation of methane source strengths for four latitude boxes from 0 to 1800 CE, using ice core data as the basis for each box input and calculating source strengths based on transport and oxidation rates where core data is not available. Explanation of the box model calculations are available in the methods section of the manuscript. Read Me Data supporting the paper A Global Atmospheric Methane Record from a Tropical Ice Core (in review) Authors Kara A. Lamantia, Lonnie G. Thompson,Mary E. Davis, Ben Riddell-Young, Ivo Strawson, Emilie Beaudon, Ellen Mosley-Thompson, Newton Nguyen, and Edward J. Brook Overview Operating System - macOS or Windows Coding software - Python Required packages - numpy, pandas, matplotlib, scipy, & seaborn Installation typically requires less than 10 minutes on a standard desktop computer/laptop with an internet connection. Figure 1 - Files The following files are available in this repository to enable the recreation of Figure 1, panels a, b, and c. Core data includes both data from this study and other previous studies. Figure 1 core data.xlsx README tab contains citations to all data used from previous studies Figure 1ab and Figure 1c tabs contain the core data necessary to recreate the full Figure 1. Figure 1.py The code to recreate Figure 1 plotting all the core data referenced in the manuscript. Figure 2 - Files The following files are available in this repository to enable the running of the four-box model described in the main text. Core data from this study is presented as 20- year avgs and polar data obtained for the model is from (Mitchell et al., 2013 and Rhodes et al., 2013). - Mitchell-GISP2.csv - Mitchell-WAIS.csv - Rhodes_NEEM.csv - Summit_20yr_avgs.csv Figure 2 Model Runs.py The four-box model code using only polar data (GISP2, NEEM, and WAIS) to estimate latitudinal methane source strengths in Tg/yr and the four-box model code with the inclusion of the data from the Huascaran, Peru summit core to estimate latitudinal methane source strengths in Tg/yr. Outputs include two .csv files necessary for plotting Figure 2 Figure 2 abc.py The code to recreate Figure 2 plotting both the core data from Figure 1a and the model results with and without the SCA core data. Demo Figure 1 Run: python "Figure 1.py" Expected Output : Figure 1 panels, a,b, and c Runtime: Less than one minute on a standard desktop/laptop Figure 2 Run: python "Figure 2 Model Runs.py" Expected Output: Two .csv files contained methane source strenghs Runtime: Less than one minute on a standard desktop/laptop Run: python "Figure 2 abc.py" Expected Output: Figure 2 panels, a,b, and c Runtime: Less than one minute on a standard desktop/laptop License This repository is released under the Creative Commons Attribution 4.0 International. See right panel for additional details.