name: Rob Roebeling
date: 2003-05-22 08:15 UTC
Briefing 21-05-2003, 10:00 UTC
Cloud conditions for measurements are stratocumulus fields
(5000 - 8000 ft) and broken cumulus (3000 - 5000). A flight
with the Merlin is planned. Departure time 12:45 UTC. For the
track we selected the sea land flight i.e. : Rotterdam to sea
box (to most westerly point A), Rotterdam, Cabauw and then
track 3 (Lichtenvoorde). Along the track profiles are flown in
the stratocumulus layer.
Briefing 22-05-2003, 6:15 UTC
Cloud conditions stratus between 1000 - 9000 ft. Due to the
high freezing level (9500 ft) the clouds phase is water. Only 1
aircraft (Merlin) and 1 flight is left for measurements. A flight
with the Merlin is planned. Departure time 10:00 UTC local
time. Track from Rotterdam to Cabauw and then track 3 to
Lichtenvoorde. The Merlin will measure profiles in the vicinity
of Cabauw.
name: Rob Roebeling
date: 2003-05-21 07:38 UTC
Briefing 6:15 UTC
2 flights are planned. The departure time is 7:00 UTC and the
estimated duration of the flight 2 hours. The aircraft will fly
from Rotterdam to Cabauw and then fly along track nr 3 in
Easterly direction. The Partenavia (METEO 2) is scheduled at
flight level 100, which is on top the the highest cloud layer
(broken stratocumulus layer of 3000 ft). The Merlin is
scheduled at flight level 110. This aircraft will fly in two cloud
layers (2000-3000 ft cumulus) and 4500-7500 ft
stratocumulus). When changing level the aircraft will make a
vertical sounding of the cloud layers.
Further plans about a second flight today will be made after
the return of the morning flight (appr 10:30 UTC).
Note that for the Partenavia after the morning flight will leave
the BBC2 campaign and return to Germany. The Dornier,
which has problems with their generator, will return to the UK
today. The Merlin will be the only aircraft left for further
measurements, until noon 23 May 2003.
name: Rob Roebeling
date: 2003-05-20 08:34 UTC
Briefing 6:15 UTC
3 flights were planned. Departure time 7:30 UTC. The aircraft
will fly track 3 to the east (Lichtenvoorde). The METEO 1 will
fly at level 100, the METEO 2 at level 110 and the METEO 3
at level 120. Beside the flight at fixed level the Merlin will
make a sounding over Cabauw i.e.: a climb from cloud base to
cloud top during which cloud physics are measured. Note that
the actual decision on the sounding depends on clearance
from air trafic control and the meteorological conditions at the
moment of passing Cabauw.
PS. At time of writting this report the METEO 3 did not take
off yet due to problems with the generator that provides the
measurement instruments with power.
name: Rob Roebeling
date: 2003-05-19 10:52 UTC
Briefing 10:00 UTC
No flights are planned today.
Due to slow passage of the frontal system the polar air will
reach the North Sea at 14:00 UTC in the most optimistic
prediction. This is considered too late for radiation flights with
the Partenavia and Merlin. In addition the polar air is unstable.
Over the UK cloud tops still reach appr. 20000 ft, which is too
high. Both uncertainties made that we decided to cancel
today’s flights.
name: Rob Roebling
date: 2003-05-19 07:50 UTC
Briefing 6:15 UTC
In the morning no flights are planned. The passage of a cold
front makes that clouds are organised in 3 layers. The top
layer reaches to the tropopause, which makes the situation
unfavourable for any radiation measurments.
The unstable air behind the front may be interesting for a
flight over the North Sea. The decision on such a flight
depends on the level of unstability, the height of the cumulus
cloud tops and the exact timing of the front passage. Pending
this development the next briefing is planned at 10:00 UTC.
name: Rob Roebeling
date: 2003-05-18 11:19 UTC
Briefing 10:30 UTC
During the morning three successful flights were made over
cumulus and stratocumulus cloud layers. Few (but not
significant) amounts of cirrus were reported.
For the afternoon no further flights are planned. Reasoning is
that the situation of cumulus and stratocumulus cloud layers
is not very different from the morning. However, during the
afternoon a considerable coverage of cirrus is expected,
which in not favourable for the aimed measurements.
name: Rob Roebeling
date: 2003-05-18 09:02 UTC
Briefing 18-05-2003 (6:15 UTC)
Like yesterday the conditions are strongly variable .
Depending on the local situation the aircraft will fly over a
layer of cumulus clouds (with tops to 3500 ft) or over a field
of stratocumulus (with tops to 8000 ft). Since both
situations are of interest for cloud measurements it was
decided to fly.
3 flights were planned. Take-off time 7:30 UTC. Track chosen
for the flight was 2, from Cabauw is north eastward in the
direction of Lochum. The flight levels selected for the flight
were:
Merlin :Flight Level 100
Partenavia :Flight Level 110
Dornier :Flight Level 120
Awaiting the return of the 3 aircraft a second briefing is
planned at 10:15 UTC.
name: Rob Roebeling
date: 2003-05-17
Briefing 17-05-2003 (10:00 UTC)
The conditions for flighing were strongly variable. A flight
could be useful when the aircraft could flight in a field of
cumulus and stratocumulus (tops to 10000 ft). It was decided
to attempt to fly in such a field.
3 flights were planned. Take-off time 11:15 UTC. Track
chosen for the flight was 7, from Cabauw is southward
direction to Gilze-Rijen. The flight levels for chosen were:
Merlin :Flight Level 100
Partenavia :Flight Level 110
Dornier :Flight Level 120
A note is that due to problems with the power supply needed
to start the Merlin, this aircraft took off at 13:00
UTC.
name: Rob Roebeling
date: 2003-05-17 07:47 UTC
Briefing 6:00 UTC
For the moning no flights have been planned. The clouds of
the passing front are too and cloud top height for making
flights with the Dornier and the Partenavia. For measing cloud
physics with the Merlin the precipitation makes the cloud less
favourable for measing cloud physics.
Awaiting the situation that will develop after the passage of
the front, a second briefing is planned at 10:00 UTC.
name: Rob Roebeling
date: 2003-05-16 07:54 UTC
Morning Briefing
The morning flights with all aircrafts are canceled.
The meteorologiocal conditions are clear sky with cirrus
coming in from the west. Since cumulus is expected to
develop around 10:00 UTC and cirrus will increase during the
day, the proposal was to make an early albedo flight (8:00
UTC). The conditions were considered not perect for an
albedo flight due to:
1. the considerable amout of cirrus (6/8 octa) coming in from
the west
2. the solar irradiance at 8:00 UTC is still low
Planning for the afternoon
In order to see whether it is usefull to have a flight in the
cumulus clouds that develop in the afternoon a second
briefing is planned at 9:30 UTC.
name: Rob Roebeling
date: 2003-05-15 08:12 UTC
General Information:
The Merlin has problems with its navigation system. Aircraf
staff in working on repairing the system. Furher flight with the
Merlin are postponed untill the problem is solved.
For today scatter cumulus (5/8) are expected with cloud tops
till appr. 10000 ft. The highest cloud cover is expected
around local noon. Two flights are planned. Both will take off
at 12:00 local time. The flight route is Rotterdam, Cabauw
and then track 4 (to Gennep). The flight with the Partenavia
will be at 9000 ft. The flight with the Dornier will be at 10000
ft. Depending on the circumstances during the flight track 4
will be flown 3 or 4 times.
name: Rob Roebeling
date: 2003-05-14 11:41 UTC
Planning for 14 may 2003
No flight is planned with the Partenavia due to unfavourable
conditions for this aircraft.
A flight with the Merlin is planned. The track to be flown is
one over both sea and land. In total two lags will be flown.
The first lag starts at point E (over the sea area) to
Rotterdam, to Cabauw and then to Lichtevoorde (track 3).
The aircraft will fly at an altitude of 4000 ft. This corresponds
with the cloudbase level of the cumulus clouds.
The second track starts at Lichtevoorde, to Cabauw, to
Rotterdam and then to point E (over the sea area). This track
will be flown in the cloud base of altostratus layer at 7500 ft.
The tack off time at Rotterdam is schedules at 15:30. The
expected duration of the flight is 2 hours.
name: Rob Roebeling
date: 2003-05-14 06:54 UTC
Status flights at 6:00 UTC
It was decided to make no flights in the morning. Only one
airplane is available, the Patenavia. Based on the Meteo
briefing of 6:00 UTC the cloud conditions over land and over
sea were considered unsuitable for flights with this aircraft.
Over the North Sea a large cumulus/stratocumulus field is
potentially interesting for flights. However, the cloud tops of
this field reach up till 7500-8500 ft, which is too high for the
Patenavia. Over land a front causes an unstable atmosphere,
which results too strong convection for flights.
Scheduled next briefing
The cumulus/stratocumulus field over the North Sea is shifting
eastward. Subsidence of dry air from higher altitudes may
lead to lowering of the cloud tops of this field. Pending this
development and awaiting the availability of the Merlin aircraft
(again at 11:00 UTC) the decision on flights is postponed to
the second briefing at 10:00 UTC in Rotterdam.
name: Pier Siebesma
date: 2003-05-09 08:46 UTC
date of flights: 08-05-2003
Paternavia:
Takeoff: appr. 9:40 local time
Return time: appr. 11:45 local time
flight pattern: R'dam-Cabauw-GilzeRijen-Eindhoven-Volkel-
Soesterberg-Cabauw-Gilzerijen-R'dam
flight height: 2000ft
climb from 2nd pass over Cabauw to Gilzerijen from 2000ft to
10000ft.
Dornier:
Take0f: appr. 9:45 local time
return time appr 11:00 local time
flight pattern: R'dam-Cabauw-Gilzerijen-Eindhoven-Volkel-
Soesterberg-Cabauw-R'dam
flight height: 10000ft
Merlin:
Takeoff: 10:10 (local time)
Return time: appr 11:25
flight pattern: (see Dornier)
plus an additionial profile measurement over Lopik (10:50-
11:05 local time ) from 2000ft to 10000ft.
Conditions: Clear sky over Cabauw, Soesterberg.
Some cirrus and altocumulus (between 1 and 3 octa) between
Gilzerijen and Volkel.
name: Pier Siebesma
date: 2003-05-07 07:00 UTC
Flight Briefing.
Plane: Dornier (Meteo3)
Flight date: 06052003
Flight time: 14:55 - 16:21 (local time)
Flight height: 10000ft
Pattern: Airport R'dam - Cabauw- Airport R'dam ( 5 times)
name: Pier Siebesma
date: 2003-05-05 13:29 UTC
Today there has been one testflight with the Merlin in the
selected Northsea box. Six legs have been flown from A
(51:58'NB, 2:30'OL) to D (51:58'NB, 3:21OL) at several
flightlevels between 9000ft and 10000ft. Flighttime from 10am
to 13pm (local time). Main purpose was to test the
consistency between the various different probes that
measure cloud liquid water (q_liq)and ice water content
(q_ice). Results were satisfactory.
name: Wouter Knap
date: 2003-05-05 07:07 UTC
Today (Monday 5 May):
Paternavia stays on the ground
Merlin test flight over North Sea, in direction of cold front,
10LT-13LT
Dornier flight uncertain due to lidar installation
14LT: Debriefing, call to Cabauw 15LT
Radiosondes Cabauw cancelled, unless Dornier flies.
name: Wouter Knap
date: 2003-05-04 11:13 UTC
Today (Sunday 4 May):
11:45LT: Dornier cancelled
12:30LT: Paternavia cancelled
Tomorrow (Monday 5 May):
8:00LT: Briefing Rotterdam
8:30-9:00: Call to Cabauw
Possible flight plan:
Test flights clouds
Wish: front comes in slowly
Merlin: morning?
Paternavia?
Dornier at the ground (lidar installation), possible afternoon
test flight
Transponder code: 7067
Radiosonde: 6, 9, 15 UTC 500 mbar
name: Wouter Knap
date: 2003-05-04 07:28 UTC
12hLT: Final decision on flight plan
13hLT: Possible flight (2-3 hours):
Paternavia (600m) Dornier (3000m)
Rotterdam-Cabauw-GilzeRijen-Eindhoven-Volkel-Soesterberg-
Cabauw-Rotterdam
Tethered balloon 11-12hLT, balloon down:12h30LT
name: Wouter Knap
date: 2003-05-03 10:44 UTC
Today (Saturday) no flights.
Radiosonde Cabauw: 18 UTC (500 mbar)
Plan for tomorrow (Sunday):
8:00 LT: Briefing Rotterdam Airport
9:00 LT: Call to Cabauw
12:00 LT: Possible flight
Radiosondes Cabauw: 6, 9, 15 UTC (500 mbar)