HALLEY BAY 1987 OZONESONDE DATA
Brian G. Gardiner
British Antarctic Survey
Madingley Road
Cambridge, CB3 0ET, U.K.
Issued: 31 March 1988
________________________________________
DATA
This disc contains tabulations of the results of the ozonesonde
programme at Halley Bay (76 deg S, 27 deg W) in 1987.
The data tabulations are, like this file, in printable ASCII.
There is one file per ozonesonde ascent. The data files should be
read in conjunction with the Schedule of Flights (see below),
where abnormal conditions affecting the data are noted. Most of these
are accounted for by the following three types of problem:
(a)
Temperatures were missing from the ozonesonde flights of June 18,
August 3 and September 30. On these occasions the temperature
profile has been taken from the regular 1200 UT radiosonde ascent
of the same day.
(b)
On the flights of August 1, August 27, September 28 and November 4,
the ozone sensor exhibited spurious instrumental oscillations.
Plausible ozone profiles were retrieved by arbitrarily selecting
the maxima of these oscillations on August 27 and September 28, and
the minima on November 4, whereas on August 1 no clear choice was
possible and the oscillations have been left untouched.
(c)
On August 20 and October 10 the balloon burst without reaching the
50 mbar level. The absolute values of column ozone should
certainly be disregarded for these flights, although the relative
values are correct.
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SCHEDULE OF FLIGHTS
In this table, P is the final pressure reached by the ozonesonde.
Date
1987
P
mbar
Apr 13
17
7.8
19.0
Jun
25.4
4
Comments
Ozone calibration data interpolated from 939 mbar
18
10.0
Jul
7
16
26
12.0
5.8
31.9
Aug
1
5.9
3
20.0
4
6
9
11
13
15
17
20
22
25
26
27
28
29
30
31
13.7
33.0
13.2
12.3
10.0
13.8
8.6
54.6
13.8
13.0
20.2
11.1
11.5
10.0
12.7
10.7
1
2
3
4
5
6
9
11
13
16
17
18
19
20
21
23
24
25
26
28
29
30
9.0
37.1
24.4
13.0
9.6
12.1
7.8
9.0
11.2
14.3
12.2
10.9
15.6
18.5
13.4
16.1
7.4
6.6
4.2
17.4
19.2
10.7
2
17.2
Sep
Oct
to 400 mbar.
Pressures interpolated from limited data, and
extrapolated after 20 mbar.
Temperatures taken from 1200 UT radiosonde ascent.
Missing ozone data between surface and 250 mbar
inferred from Aug 4 ascent. Instrumental oscillations.
Pressures retrieved from limited data.
Temperatures taken from 1200 UT radiosonde ascent.
Premature balloon burst.
Instrumental oscillations: ozone maxima selected.
Instrumental oscillations: ozone maxima selected.
Temperatures taken from 1200 UT radiosonde ascent.
Nov
3
4
5
7
10
11
13
15
17
19
21
24
4.9
4.5
5.0
7.6
83.0
23.5
5.0
4.0
7.0
7.0
9.4
8.8
28
5.0
4
9.0
14
23
10.4
7.0
Pressures unreliable after 6.6 mbar.
Premature balloon burst.
Radiosonde calibration drifted after about 34 mbar:
subsequent pressures and temperatures corrected to be
compatible with 1200 UT radiosonde ascent.
Instrumental oscillations from 273 mbar to 26.5 mbar:
ozone minima selected.
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KEY TO THE TABULATED DATA
P
atmospheric pressure
T
atmospheric temperature
P3
ozone partial pressure
R3
ozone mixing ratio (parts per million by volume)
THETA
potential temperature
Z
height above mean sea level (geopotential metres)
COL. O3
column ozone: this is the integrated ozone column
above the level shown, and includes a residual amount of
ozone above the final ozone data point, calculated on
the assumption of a constant ozone mixing ratio from that
point to the top of the atmosphere. This assumption will
be invalid in the few cases where the balloon failed to
reach the layer of relatively constant ozone mixing ratio,
e.g. if the final pressure is greater than about 30 mbar.
Surface wind direction refers to the origin of the wind, thus 270
degrees is a wind from the west. Surface wind speed is in knots.
Cloud information is derived from the cloud group in the TEMP
message (WMO code FM 35-V). The cloud cover in oktas therefore
refers to low-level cloud only (or to medium-level cloud if there
is no low-level cloud). The remaining three numbers are the cloud types
CL, CM, and CH (WMO codes 0513, 0515 and 0509) for low-, medium- and
high-level clouds respectively.