 |
| Titel |
Stratospheric lifetime ratio of CFC-11 and CFC-12 from satellite and model climatologies |
| VerfasserIn |
Lars Hoffmann, Charlotte Hoppe, Rolf Müller, Geoffrey S. Dutton, John C. Gille, Sabine Griessbach, Ashley Jones, Catrin I. Meyer, Reinhold Spang, C. Michael Volk, Kaley A. Walker |
| Konferenz |
EGU General Assembly 2015
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250102409
|
| Publikation (Nr.) |
 EGU/EGU2015-1725.pdf |
|
|
|
|
|
| Zusammenfassung |
| Chlorofluorocarbons (CFCs) play a key role in stratospheric ozone loss and are strong
infrared absorbers that contribute to global warming. The stratospheric lifetimes of CFCs are
a measure of their stratospheric loss rates that are needed to determine global warming and
ozone depletion potentials. We applied the tracer-tracer correlation approach to zonal mean
climatologies from satellite measurements and model data to assess the lifetimes of CFCl3
(CFC-11) and CF2Cl2 (CFC-12). We present new estimates of the CFC-11/CFC-12 lifetime
ratio and the absolute lifetime of CFC-12, based on a reference lifetime of 52 yr for CFC-11.
We analyzed climatologies from three satellite missions, the Atmospheric Chemistry
Experiment-Fourier Transform Spectrometer (ACE-FTS), the HIgh Resolution Dynamics
Limb Sounder (HIRDLS), and the Michelson Interferometer for Passive Atmospheric
Sounding (MIPAS). We found a CFC-11/CFC-12 lifetime ratio of 0.47 ± 0.08 and a
CFC-12 lifetime of 112(96 - 133) yr for ACE-FTS, a ratio of 0.46 ± 0.07 and a
lifetime of 113(97 - 134) yr for HIRDLS, and a ratio of 0.46 ± 0.08 and a lifetime of
114(98 - 136) yr for MIPAS. The error-weighted, combined CFC-11/CFC-12 lifetime
ratio is 0.46 ± 0.04 and the CFC-12 lifetime estimate is 113(103 - 124) yr. These
results are in excellent agreement with the recent Stratosphere-troposphere Processes
And their Role in Climate (SPARC) reassessment, which recommends lifetimes of
52(43 - 67) yr for CFC-11 and 102(88 - 122) yr for CFC-12, respectively. Having
smaller uncertainties than the results from other recent studies, our estimates can
help to better constrain CFC-11 and CFC-12 lifetime recommendations in future
scientific studies and assessments. Furthermore, the satellite observations were
used to validate first simulation results from a new coupled model system, which
integrates a Lagrangian chemistry transport model into a climate model. For the coupled
EMAC/CLaMS model we found a CFC-11/CFC-12 lifetime ratio of 0.48 ± 0.07 and a
CFC-12 lifetime of 110(95 - 129) yr, based on a ten-year perpetual run. Closely
reproducing the satellite observations, the new model system will likely become a
useful tool to assess the impact of advective transport, mixing, and photochemistry
as well as climatological variability on the stratospheric lifetimes of long-lived
tracers.
Reference:
Hoffmann, L., Hoppe, C. M., Müller, R., Dutton, G. S., Gille, J. C., Griessbach, S., Jones,
A., Meyer, C. I., Spang, R., Volk, C. M., and Walker, K. A.: Stratospheric lifetime ratio of
CFC-11 and CFC-12 from satellite and model climatologies, Atmos. Chem. Phys., 14,
12479-12497, doi:10.5194/acp-14-12479-2014, 2014. |
|
|
|
|
|
|