
Simulations of cosmogenic 14 CO using the three‐dimensional atmospheric model MATCH: Effects of 14 C production distribution and the solar cycle
Author(s) -
Jöckel Patrick,
Lawrence Mark G.,
Brenninkmeijer Carl A. M.
Publication year - 1999
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999jd900061
Subject(s) - stratosphere , troposphere , cosmic ray , atmospheric sciences , atmospheric chemistry , solar energetic particles , tracer , atmosphere (unit) , physics , solar cycle , atmosphere of earth , environmental science , computational physics , meteorology , solar wind , ozone , astrophysics , nuclear physics , plasma , coronal mass ejection
Most atmospheric 14 CO is produced by cosmic rays in the lowermost stratosphere and upper troposphere. The main removal process for 14 CO is oxidation by OH radicals. Assuming that the spatial distribution of OH is well known, 14 CO can be useful as a test‐tracer for the transport properties of a three‐dimensional chemical model. Conversely, if the transport schemes of the model are sufficiently realistic, in particular with respect to stratosphere‐troposphere exchange, the OH distribution can be evaluated. In either case, it has to be assumed that the source of 14 CO is known in sufficient detail. Two presently available distributions of cosmogenic 14 C production are implemented into the Model of Atmospheric Transport and Chemistry (MATCH). The tropospheric 14 CO concentrations that are obtained are relatively insensitive to the source differences. The calculations for one source distribution are performed for solar minimum and solar maximum conditions. The spatial distribution of 14 CO is almost unaffected by the solar activity, and the absolute concentration levels can be scaled to the actual solar cycle conditions.