Winds 295 degrees at 11 m/s, pressure 1012.2 and steady, partly
cloudy with cirrus and stratus, dry bulb 9.5C, wet bulb 6.0C, SST 11.6
Pressure reached maximimum at 1400 UTC of 1013.7. Winds then shifted
from SW to WNW.
SEA STATE:
Westsouthwesterly 2-3 M swell, wind waves from 295 at 1 M
INSTRUMENTS/SYSTEMS STATUS
Sea Surface Measurements:
DMS: Average seawater DMS
concentration approximately 2nM.
DMSP/DMSO:
Incubation from 12/06 showed a 6 hour turnover time for DMSP.
NH4+NH3/pH:
CO:
Surface seawater concentrations have a diurnal cycle with a late night
minimum of 0.5 and an afternoon maximum of 1.5 nM.
NMHC:
Low ppb levels of butane. sub ppb levels of pentane in equilibrated air
samples.
CO2:
Nitrate/Chlorophyll:
Nitrate concentrations about 3 uM.
Seawater fluorescence is being recorded continuously.
Surface seawater samples are being collected every 4 hours
for discrete chlorophyll analysis.
Atmospheric Measurements:
DMS:
SO2:
Concentrations range from 10 to 20 ppt.
NH3:
Using oxalic acid coated filters.
CO:
Concentrations near 60ppb.
NMHC:
O3:
Surface concentrations back in to the 17 to 23 ppb range.
Nitrogen oxides and PAN:
Radon:
CO2:
Solar Radiation:
Aerosol physics:
At 11:00 2 major modes - 35 and 90 nm. Ntot=600pp/cc.
Aerosol chemistry:
2-stage and 7-stage impactors currently sampling for time periods
ranging from 24 to 72 hours for IC, total organic carbon, speciated
organics, and gravimetric analysis.
Aerosol optical properties.
TDMA-RH: During the last few days we
have observed several occasions with low growth factors ~1.4, as we move
into high pressure regions.
System operational with 4 sondes/day. A total of 185 sondes have been
launched todate. An extra sonde will be launched at 2000 to support the
aircraft overflight.
Routine Weather Observations: Going well.
Satellite Observations: None
CTD Cast Schedule: None.
SPECIAL PLANNED OBSERVATIONS (NEXT 24-HOURS):
The C-130 will be working in the vicinity of Discoverer today for a flux
intercomparison. Measurements will continue aboard Discoverer until
0600 UTC when we will head for Hobart. We expect to be alongside
CSIRO at 2200 (0900 LT) tomorrow.
PAST 24-HR OPERATIONS SUMMARY:
Seawater and mospheric sampling on station.
OTHER COMMENTS:
This will be the final status report from Discoverer for ACE-1. I would like
to especially thank Jim Moore, UCAR-Office of Field Project Support, for
orchestrating the excellent communications between the Ops center and
research platforms, for representing the needs and opinions of the scientists
aboard Discoverer and Southern Surveyor at the Ops center and for his
outgoing good-natured attitude which certainly helped to keep the whole
experiment together.