 |
| Titel |
On the use of the correction factor with Japanese ozonesonde data |
| VerfasserIn |
G. A. Morris, G. Labow, H. Akimoto, M. Takigawa, M. Fujiwara, F. Hasebe, J. Hirokawa, T. Koide |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 3 ; Nr. 13, no. 3 (2013-02-01), S.1243-1260 |
| Datensatznummer |
250017627
|
| Publikation (Nr.) |
 copernicus.org/acp-13-1243-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| In submitting data to the World Meteorological Organization (WMO) World
Ozone and Ultraviolet Data Center (WOUDC), numerous ozonesonde stations
include a correction factor (CF) that multiplies ozone concentration profile
data so that the columns computed agree with column measurements from
co-located ground-based and/or overpassing satellite instruments. We
evaluate this practice through an examination of data from four Japanese
ozonesonde stations: Kagoshima, Naha, Sapporo, and Tsukuba. While agreement
between the sonde columns and Total Ozone Mapping Spectrometer (TOMS) or
Ozone Mapping Instrument (OMI) is improved by use of the CF, agreement
between the sonde ozone concentrations reported near the surface and data
from surface monitors near the launch sites is negatively impacted. In
addition, we find the agreement between the mean sonde columns without the
CF and the ground-based Dobson instrument columns is improved by ~1.5 % by using the McPeters et al. (1997) balloon burst climatology rather than the constant mixing ratio assumption (that has been used for the data in the WOUDC archive) for the
above burst height column estimate. Limited comparisons of coincident
ozonesonde profiles from Hokkaido University with those in the WOUDC
database suggest that while the application of the CFs in the stratosphere
improves agreement, it negatively impacts the agreement in the troposphere.
Finally and importantly, unexplained trends and changing trends in the CFs
appear over the last 20 years. The overall trend in the reported CFs for the
four Japanese ozonesonde stations from 1990–2010 is (−0.264 ± 0.036) × 10−2 yr−1; but
from 1993–1999 the trend is
(−2.18 ± 0.14) × 10−2 yr−1 and from 1999–2009
is (1.089 ± 0.075) × 10−2 yr−1, resulting in a
statistically significant difference in CF trends between these two periods
of (3.26 ± 0.16) × 10−2 yr−1. Repeating the
analysis using CFs derived from columns computed using the balloon-burst
climatology, the trends are somewhat reduced, but remain statistically
significant. Given our analysis, we recommend the following: (1) use of the
balloon burst climatology is preferred to a constant mixing ratio assumption
for determining total column ozone with sonde data; (2) if CFs are applied,
their application should probably be restricted to altitudes above the
tropopause; (3) only sondes that reach at least 32 km (10.5 hPa) before
bursting should be used in data validation and/or ozone trend studies if the
constant mixing ratio assumption is used to calculate the above burst column
(as is the case for much of the data in the WOUDC archive). Using the
balloon burst climatology, sondes that burst above 29 km (~16 hPa), and perhaps lower, can be used; and (4) all ozone trend studies
employing Japanese sonde data should be revisited after a careful
examination of the impact of the CF on the calculated ozone trends. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|