ACE-1 R/V DISCOVERER STATUS FORM

DATE/TIME: (95113019)

PREPARED BY: Tim Bates

• LOCATION PRESENT: LATITUDE: 45 06.1S LONGITUDE: 142 54.8E
• LOCATION -6 HOURS: LATITUDE: 45 00.0S LONGITUDE: 143 00.0E
• LOCATION -12 HOURS: LATITUDE: 45 20.3S LONGITUDE: 142 00.7E
• LOCATION -18 HOURS: LATITUDE: 44 28.5S LONGITUDE: 140 48.6E

PRESENT WEATHER:

Winds 290 degrees at 12 m/s, pressure 1002.1 and rising, partly cloudy, dry bulb 10.5C, wet bulb 9.0C seawater 10.3C.

SEA STATE:

West southwesterly 3-4 M swell, wind waves from 290 at 1-2 M

INSTRUMENTS/SYSTEMS STATUS

---

• Sea Surface Measurements:

  1. DMS: Current concentration 1.3nM
  2. DMSP/DMSO: Samples collected every 8 hours for particulate and dissolved DMSP and DMSO.
  3. NH4+NH3/pH:
  4. CO: Surface seawater concentrations have a diurnal cycle with a late night minimum of 0.8 and and an afternoon maximum of 1.2 nM.
  5. NMHC: Butane ~2ppb; Pentane ~0.4ppb in equilibrated air samples.
  6. CO2:
  7. Nitrate/Chlorophyll: Nitrate concentrations south of the front at 45-46 S are approx 25uM, north of the front approx 6.4 uM. Seawater fluorescence is being recorded continuously. Surface seawater samples are being collected every 4 hours for discrete chlorophyll analysis.

  ---

• Atmospheric Measurements:

  1. DMS: Current concentrations at 45S are approximately 120 ppt.
  2. SO2: Concentrations approximately 5 ppt.
  3. NH3: Using oxalic acid coated filters. Concentrations measured with oxalic acid coated filters range from 3 to 10 pptv.
  4. CO: Concentrations near 60ppb.
  5. NMHC: Butane ~8ppt; Pentane ~1ppt
  6. O3: Concentrations range from 20-24 ppb.
  7. Nitrogen oxides and PAN: NO<4 ppt and NOy ~400 ppt. NO2 not operational.
  8. Radon:
  9. CO2:
  10. Solar Radiation:
  11. Aerosol physics: Aerosol physics: Sizing instrumentation fully operational. At 1200GMT NW air stream, "closed" size distribution, modes at 30 and 110nm . UFCN = 270, CN = 250 pp/cc At 1500GMT - perfect event! After pressure "bump" particles are up from monomode 12nm to 18-20nm in 4hr(at 1900). Ntot=800-1000pp/cc. Clean, no soot. Wind from NWW.
  12. 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.
  13. Aerosol optical properties:
  14. TDMA-RH:
  15. TDMA-Thermal:

  ---

• ISS Status and Schedule:

  System operational with 4 sondes/day. Extra sondes were launched at 0800 and 1400 to support Lagrangian #2.

  ---

• Routine Weather Observations: Going well.
• Satellite Observations: None
• CTD Cast Schedule: None.

  ---

• SPECIAL PLANNED OBSERVATIONS (NEXT 24-HOURS):

  A meeting will be held at 2100 to discuss ship operations for the next several days.

  ---

• PAST 24-HR OPERATIONS SUMMARY: Transit to Lagrangian 2 starting point. Seawater sampling only for second half of day because winds were abaft the beam. Sampling commenced at the starting point (45S, 143E) at 1000 UTC. Extra sondes were launched at three hour intervals and one smart balloon inflated. The Lagrangian was called off at 1400. At 1430 the pressure stopped rising and remained constant at 998 mb. At 1500, under clear skies we, observed an intrusion of ultra fine particles into the marine boundary layer and their subsequent growth over the next several hours. The details are listed above under aerosol physics.
• OTHER COMMENTS: A synoptic situation, similar to that described above, appears to be located 15 degrees west of us. Are we ready to try it again?