Preliminary Cruise Report

Cruise: ‘Red bloom study’

Dates: 24-26 September 2012

Chief Scientists: Craig McNeil (R/V Inferno) and Binglin Li (R/V Forerunner)

Investigators: Antonio Baptista (Director CMOP), Peter Zuber (Initiative Leader), Gordon Farquharson and Chris Chickadel (aerial imagery), Binglin Li, Tawnya Peterson, Joe Needoba (shipboard measurements), Craig McNeil (AUV), others?....

Goals:We implemented a ‘rapid-response’ study timedduring the peak of the 2012 M Rubrum (MR) red water bloom. Primary objectives were: 1) document the temporal and spatial variability of the bloom using a combination of aerial, shipboard and AUV surveys, with the overarching goal of estimating excess primary productivity in the estuary by MR and the impact of this primary productivity on the CR ecosystem; and 2) understand diel variability in MR distributions, especially any vertical migrations of the MR in response to forcing by sunlight and tidal currents and vertical shear.

Results:Presented in the tables and figures below are time lines for each sampling platform and some examples of exciting preliminary results and findings.

1)Aerial surveys: see Figures 1, 2, 3.

2)R/V Forerunner sampling: see Figure 4 and Table 1.

3)AUV sampling: see Figures 5,6 and Table 2.

Figure 1: Time line of the plane surveys.

Figure 2: Example flight path on 09/25/12 at 09:06h. The second panel shows the intended flight path (white line) and the imaging area (yellow box).

Figure 3:Selection of mapped imagery and bloom proxies ('bloomMask', darker can indicate a stronger bloom signature) on 26-Sep-2012 during 1400h to 1500h. (Courtesy Chris Chickadel and Gordon Farquharson, APL/UW)

Figure 4:Distributions of M. rubrum and cryptophytes measured on the R/V Forerunner during 26-Sep-2012. The last panel shows a first estimate of total phycorytherin pigment concentration - for use in calibrating the AUV data - based on measured M. rubrum counts and an approximation that each M. rubrum cell has 25 times the pigment of a single cryptophyte.A clear pattern of diel vertical migration is apparent. (Courtesy Binglin and Zuber)

Figure 5: Dissolved oxygen (upper panel) and raw phycoerythrin count measured by the AUVs during the main four Missions #61-64. A cumulative offset of 10 psu on the salinity scale between missions was added to avoid overlap. High O2 saturations are observed in the red water blooms, identified by high phycoerythrin counts (PE-570). [Courtesy McNeil]

Figure 6: Example of across channel AUV section (leg 2, M64) showing strong subsurface signatures of the bloom waters at approximately 1 m depth. [Courtesy McNeil]

Table 1: Sampling stations on the R/V Forerunner.

Cruise (Date) / Station name / Time
AUV Cruise (9/25/2012) / SC02-B / 9:51:00
SC02-S / 9:54:00
YB-B (2m) / 10:59:00
YB-S (RW) / 11:04:00
Sat03-B / 11:37:00
Sat03-S / 11:41:00
ML01-B / 11:30:00
ML01-S / 11:35:00
ML03-B / 12:50:00
ML03-S / 12:53:00
ML05-B / 1:10:00
ML05-S / 13:15:00
NC01-B / 13:15:00
NC01-S / 13:40:00
NC02-B / 14:05:00
NC02-S (RW) / 14:07:00
Sat01-B / 14:40:00
Sat01-S / 14:43:00
SC11-B / 15:15:00
SC11-S / 15:20:00
AUV Cruise (9/26/2012) / NC02-1B / 13:25:00
NC02-1S (RW) / 13:20:00
NC02-2B / 14:10:00
NC02-2S / 14:15:00
RW1427 / 14:27:00
1447 / 14:47:00
1458 / 14:58:00
NC02-3B / 15:10:00
NC02-3S / 15:00:00
NC02-4S / 16:15:00
NC02-4B / 16:15:00
NC02-5S / 17:10:00
NC02-5B / 17:10:00
NC02-6S / 18:05:00
NC02-6B / 18:10:00
NC02-7S (RW) / 18:55:00
NC02-7B / 18:57:00
NC02-8S / 19:58:00
NC02-8B / 20:01:00
2016 / 20:16:00
NC02-9S / 20:58:00
NC02-9B / 21:00:00
2130-4m / 21:30:00
2135 / 21:35:00
NC02-10S / 21:55:00
NC02-10B / 22:00:00
2200-4m / 22:00:00

Table 2: Summary of AUV deployments.

Mission / SN # / Location / Date / Start / End / Sensors / Ship / Problems
CMOP- 57 / 365 / CR North Channel MR-1 / 9/24/2012 / 14:20:00 / 15:38:00 / O2,SBE-55 / Infermo / test adcp, along channel / fighting currents going east at start
CMOP- 58 / 364 / CR North Channel MR-1 / 9/24/2012 / 16:56:00 / 18:09:00 / O2,SBE-55,ECO / Inferno / 5 shoreward legs
CMOP- 59 / 364 / CR North Channel MR-1 / 9/25/2012 / 10:45:00 / 12:07:00 / O2,SBE-55,ECO / Inferno / 3 shoreward legs / timeout
CMOP- 60 / 364 / CR North Channel MR-1 / 9/25/2012 / 14:04:00 / 14:26:00 / O2,SBE-55,ECO / Inferno / stalled, aborted / stalled
CMOP- 61 / 364 / CR North Channel MR-1 / 9/26/2012 / 10:22:33 / 11:14:00 / O2,SBE-55,ECO / Inferno / west to east
CMOP- 62 / 364 / CR North Channel MR-1 / 9/26/2012 / 11:50:00 / 12:53:00 / O2,SBE-55,ECO / Inferno / east to west
CMOP- 63 / 364 / CR North Channel MR-1 / 9/26/2012 / 14:26:00 / 15:11:00 / O2,SBE-55,ECO / Inferno / east to west / swept back several times to east
CMOP- 64 / 364 / CR North Channel MR-1 / 9/26/2012 / 16:50:00 / 17:47:00 / O2,SBE-55,ECO / Inferno / cross channel, S-N-S