DOI: 10.7910/dvn/jecpn8
title: Model and observational data for Quantifying the Imprints of Stratospheric Contributions to Interhemispheric Differences in Tropospheric CFC-11, CFC-12, and N2O Concentrations
title: Version 1.0

description: WACCM model output, AGAGE ground-level measurements and ACE satellite measurements used for analysis in "Quantifying the Imprints of Stratospheric Contributions to Interhemispheric Differences in Tropospheric CFC-11, CFC-12, and N2O Concentrations" submitted to GRL
description: This file contains the sources of each of the data files contains the modeled and observational data used for analysis in "Quantifying the Imprints of Stratospheric Contributions to Interhemispheric Differences in Tropospheric CFC-11, CFC-12, and N2O Concentrations" submitted to GRL (2021-04-09)


Lower tropospheric concentrations come from the AGAGE monitoring network (Prinn et al., 2018). To fill gaps during periods of instrumental down-time, monthly means are extracted from the AGAGE 12-box model, into which the AGAGE data has been assimilated (Rigby, M. et al., 2013). Similar to Montzka, et al. (2018) and Rigby, et al. (2019), a least-squares inverse method is employed in which emissions are estimated using the data and the model without a prior constraint. The model is constrained by monthly mean baseline-filtered observations from January 1978 to December 2019, binned into semi-hemispheres (90S - 30S, 30S – eq, eq - 30N, 30N - 90N). The 5 AGAGE stations used are Cape Grim, Tasmania; Cape Matatula, Samoa; Ragged Point, Barbados; Trinidad Head CA; and Mace Head, Ireland. The instruments used were GC-ECDs for CFC-11, CFC-12, and N2O. The monthly means were computed with pollution events removed. 

ACE data are provided by P. Bernath and J. Crouse; the ACE Mission (SCISAT) is supported by the Canadian Space Agency (Bernath, 2017). 

WACCM model simulations from (Stone et al., 2018) were made available by Doug Kinnison (dkin@ucar.edu). 


References

Bernath, P. F. (2017). The Atmospheric Chemistry Experiment (ACE). Journal of Quantitative Spectroscopy and Radiative Transfer, 186, 3–16. https://doi.org/10.1016/j.jqsrt.2016.04.006

Montzka, S. A., Dutton, G. S., Yu, P., Ray, E., Portmann, R. W., Daniel, J. S., et al. (2018). An unexpected and persistent increase in global emissions of ozone-depleting CFC-11. Nature, 557(7705), 413.

Prinn, R. G., Weiss, R. F., Arduini, J., Arnold, T., Langley Dewitt, H., Fraser, P. J., et al. (2018). History of chemically and radiatively important atmospheric gases from the Advanced Global Atmospheric Gases Experiment (AGAGE). Earth System Science Data, 10(2), 985–1018. https://doi.org/10.5194/essd-10-985-2018

Rigby, M., Prinn, R. G., O’Doherty, S., Montzka, S. A., McCulloch, A., Harth, C. M., et al. (2013). Re-evaluation of the lifetimes of the major CFCs and Biogeosciences CH 3 CCl 3 using atmospheric trends, 13, 2691–2702. https://doi.org/10.5194/acp-13-2691-2013

Rigby, M., Park, S., Saito, T., Western, L. M., Redington, A. L., Fang, X., et al. (2019). Increase in CFC-11 emissions from eastern China based on atmospheric observations. Nature, 569(7757), 546–550.

Stone, K. A., Solomon, S., & Kinnison, D. E. (2018). On the Identification of Ozone Recovery. Geophysical Research Letters, 45(10), 5158–5165. https://doi.org/10.1029/2018GL077955