Vol. 24, No. 1
Data for Atmospheric Chemistry
data are essential not only for atmospheric modellers, but also for
experimental scientists studying kinetics and mechanisms of atmospheric
reactions. Over the last 20 years, and in response to the emerging problem
of the depletion of atmospheric ozone due to man made pollutants, a
group was tasked to produce evaluations of the existing chemical kinetics
data. These evaluations continuously updated and augmented results in
a series of nine peer reviewed publications in J. Phys. Chem. Ref.
Data. As the accessibility of these data appears equally important,
a new task group is now engaged in assembling, compiling, and indexing
the materials on an interactive web site.
evaluations contain two elements. Firstly, they contain a summary table
containing a list of recommended rate parameters giving the best available
values for rate coefficients, for use in models representing atmospheric
chemistry/explicitly as a system of elementary chemical reactions. Secondly
each reaction is discussed in a separate data sheet, in which the key
experimental data are summarized and the basis of the recommendation
together with its uncertainty is given.
database has been created by the former IUPAC Subcommittee for Gas Kinetic
Data Evaluation for Atmospheric Chemistry and developed at the Centre
for Atmospheric Science in the Department of Chemistry, at the University
of Cambridge <http://www.iupac-kinetic.ch.cam.ac.uk>.
The current task group, lead by Dr.
R. A. Cox, will substantially expand the content of the web site
to include not only the most current summary sheets, but also the data
for photochemical reactions (absorption cross sections, quantum yields),
heterogeneous reactions (kinetic uptake coefficients for atmospheric
gases on a range of surfaces) and the individual data sheets for each
of the (600) gas phase reactions evaluated in the past 20 years. The
current "passive" site will be converted into an interactive interphase,
including search and hyperlinks between the summary table and the data
sheets. As new data are reported, a more effective way of updating and
extending the portfolio of recommended rate coefficients will be developed;
this will be necessary to maintain an effective and ongoing communication
between laboratory scientists and atmospheric modellers.