DOI: 10.5061/dryad.zkh1893gm
title: Reconstruction of atmospheric H2 from Greenland and Antarctic firn air

description: This data set contains: firn air depth profiles of H2 from 4 polar sites
 (South Pole and Megadunes in Antarctica) and NEEM and Summit in Greenland
 used to by Patterson et al., in press to reconstruct the history of
 atmospheric H2 Matlab code for the UCI firn air model and data used in the
 reconstructions    Reference:  Patterson, J.
 D., Aydin, M., Crotwell, A. M., Pétron, G., Severinghaus, J. P., Krummel,
 P. B., Langenfelds, R. L., Petrenko, V. V., and Saltzman, E. S.:
 Reconstructing atmospheric H2 over the past century from bi-polar firn air
 records, Clim. Past, https://doi.org/10.5194/cp-2023-27, in press.
 Note:  The firn air depth profiles archived here are processed to
 remove outliers and average replicates. For raw data, please contact the
 laboratories at which the measurements were made (G. Petron, GML/NOAA; P.
 Krummel; CSIRO).  
description: The methodology used to obtain and process the data is described
 in Patterson et al., in press.
description: # Reconstruction of atmospheric H2 from Greenland and Antarctic firn air
 [https://doi.org/10.5061/dryad.zkh1893gm](https://doi.org/10.5061/dryad.zkh1893gm) This dataset contains data and model codes used to reconstruct atmospheric H2 from polar firn air profiles, as described in the following publication: Patterson, J. D., Aydin, M., Crotwell, A. M., Pétron, G., Severinghaus, J. P., Krummel, P. B., Langenfelds, R. L., Petrenko, V. V., and Saltzman, E. S.: Reconstructing atmospheric H<sub>2</sub> over the past century from bi-polar firn air records, Clim. Past, https://doi.org/10.5194/cp-2023-27, in press. ## Description of the data and file structure Files: Megadunes2004.csv NEEM2008.csv SouthPole2001.csv Summit2013.csv Format: \*.csv (comma delimited text) Content: Depth (meters), H2 (parts per billion), 1 sigma standard deviation (ppb) Notes: These data have been gravity-corrected and outliers removed as described in Patterson et al. (2023). ## Code/Software Content: UCI firn air model for simulating the propagation of various trace gases through a firn column at several polar sites. Inputs: site physical properties, trace gas physical properties, atmospheric trace gas history Output: depth profiles of trace gas content in firn air (open porosity) as a function of time Model modes: 1. historical mode (time stepping forward) in which a time series of atmospheric trace gas mixing ratio is provided 2. Green's function mode in which the propagation of a 1 year pulse of trace gas is followed in time All code files are Matlab scripts (text files, with \*.m filenames). Data files are Matlab \*.mat binary files created under under Matlab version 2022b. Main code file: model\_20231004.m Supporting code files: get\_gas\_props\_20191009.m get\_hist\_20230327.m get\_site\_props\_20230329.m Supporting data files: \\physprops\\\*physprops\*.mat These files contain physical properties for various sites \\hists\\\*hist\*.mat These contain atmospheric histories of various trace gases. Files containing "\*\_green.mat" contain atmospheric histories provided by Buizert et al. 2012. Citation: Buizert, C., Martinerie, P., Petrenko, V. v., Severinghaus, J. P., Trudinger, C. M., Witrant, E., Rosen, J. L., Orsi, A. J., 740 Rubino, M., Etheridge, D. M., Steele, L. P., Hogan, C., Laube, J. C., Sturges, W. T., Levchenko, V. A., Smith, A. M., Levin, I., Conway, T. J., Dlugokencky, E. J., … Blunier, T. (2012). Gas transport in firn: Multiple-tracer characterisation and model intercomparison for NEEM, Northern Greenland. Atmospheric Chemistry and Physics, 12(9), 4259–4277. https://doi.org/10.5194/acp-12-4259-2012). <br>