High Resolution Time Series Measurements of BioOptical and Physical Variability in the Coastal Ocean

1
High Resolution Time Series Measurements of
Bio-Optical and Physical Variability in the
Coastal Ocean as Part of HyCODE
Dickey Mooring
2
Objectives
The long-term goal of our project is to increase
understanding of the variability of IOPs and AOPs
of ocean waters and their relationships to each
other as well as to physical processes on
continental shelves.

• Specifically
• To provide the maximum number of in situ
  observations of IOPs and AOPs possible for
  calibrating, groundtruthing, and relating
  subsurface optical properties to aircraft and
  spacecraft ocean color data
• To develop, test, and validate optical models and
  high resolution interdisciplinary models of the
  coastal ocean.
• To study processes that contribute to temporal
  and spatial variability of spectral IOPs and
  AOPs. In particular, we are determining how
  temporal and spatial variability in IOPs and AOPs
  are affected by
• - Coastal physical and biological dynamics and
  larger scale circulation,
• - Wave fields,
• - Water column stratification and current shears,
• - Near surface and near bottom mixing,
• - Diurnal and seasonal biological and physical
  cycles, and
• - Riverine and runoff inflows.

3
Question 1.0

• Optical effects on solar transmission, sea
  surface albedo, and radiant heating rate
• - Hydrolight Modeling
• Inputs include daily noontime values of
  measured
• absorption and attenuation (ac-9 at 5, 11, 20
  m)
• chlorophyll-a concentration (fluorometers at
  5 and 11 m)
• VSF (within MLD)
• boundary conditions (wind speed, solar angle,
  cloud index, Ed(0,l))
• Similar past studies (Ohlmann et al., 2000) in
  the equatorial Pacific have shown that cloud
  cover, solar angle, and chlorophyll-a
  concentration have the greatest optical
  influences on solar transmission and radiant
  heating rates.

4
Results 1.0

• MLD plays the most important role in the
  variability of solar transmission (expected),
  followed by chlorophyll-a concentration and CDOM
  concentration (unexpected).
• Cloud index and solar angle have greater
  influence on variability of sea surface albedo
  and radiant heating rate.

5
Results 1.0
Spectral results are similar
6
More Analyses 1.0

• We need to make estimates of the components of
  the heat budget latent heat, evaporative heat,
  etc. Does Scott Glenn have these?

7
Question and Results 2.0

• Comparisons between in situ and remotely sensed
  measurements of Rrs(l) and derived chlorophyll-a
  concentration
• Rick Gould provided us with time series of
  SeaWiFS and MODIS data
• within a small area near our mooring site.

• Spectral shape and magnitude comparisons of
  Rrs(l) look promising. Remotely sensed Rrs(l)
  spectra appear to have atmospheric correction
  errors, visible in the blue wavelengths.

8
Results 2.0

• At first glance, it looks like OC-4 performs
  better at Chl-a gt 3.5 and Stumpf is better for
  Chl-a lt 3.5

9
More Analyses 2.0

• Rick has provided IOP data (absorption and
  backscattering) estimated using SeaWiFS
  algorithms. We will compare these IOPs with in
  situ mooring measurements.

Data Needed 2.0

• PHILLS Rrs(l) data, chl-a and IOPs generated from
  SeaWiFS, MODIS, and PHILLS data using different
  algorithms

10
Question 3.0

• Effects of CDOM on optical properties Can we use
  CDOM to trace water masses?

May 27, 2000 JD 148
June 11, 2000 JD 163
AVHRR images of Hudson River plumes (thanks to
Rutgers website)
11
Results 3.0

• CDOM is highly correlated with the inverse of
  salinity

12
Results 3.0

• Rrs(550)/Rrs(400) is significantly coherent with
  ag(440) but not with Chl-a

13
More Analyses 3.0

• Havent thought about it much yet any ideas???

Data Needed 3.0

• Satellite images and data of the Hudson River
  plumes. 3 events in 2000 May 27, June 4, and
  June 10
• Complementary Rrs(l) data to check with
  Hydrolight
• Complementary ag(l) bottle sample data to check
  our partitioning method

14
HyCODE-related Publications
Peer-reviewed papers

• Chang, G. C., T. D. Dickey, C. D. Mobley, E.
  Boss, and W. S. Pegau, Toward closure of
  upwelling radiance in coastal waters, Appl. Opt.,
  in press, 2003.
• Chang, G. C., T. D. Dickey, O. M. Schofield, A.
  D. Weidemann, E. Boss, W. S. Pegau, M. A. Moline,
  and S. M. Glenn, Nearshore physical processes and
  bio-optical properties in the New York Bight, J.
  Geophys. Res., doi 10.1029/2001JC001018, 2002.
• Dickey, T. and G. Chang, Recent advances and
  future visions temporal variability of
  bio-optical and bio-optical properties of the
  ocean, Oceanography, 14(3), 15-29, 2001.

Conference Presentations

• Chang, G. C. and T. D. Dickey, Optical impacts on
  solar transmission in coastal waters, Ocean
  Optics XVI, Santa Fe, NM, November 2002.
• Chang, G. C., T. D. Dickey, E. Boss, C. Mobley,
  and W. S. Pegau, Toward closure of in situ
  upwelled radiance in coastal waters, AGU/ASLO
  Ocean Sciences Meeting, Honolulu, HI, February
  2002.
• Chang, G. C., T. D. Dickey, O. M. Schofield, A.
  D. Weidemann, and S. M. Glenn, Temporal and
  Spatial Variability of physical and bio-optical
  properties on the New York Bight inner
  continental shelf, IAPSO/IABO 2001 An Ocean
  Odyssey Meeting, Mar del Plata, Argentina,
  October 2001.
• Chang, G. C., T. D. Dickey, and O. Schofield,
  Physical processes related to bio-optical
  properties on the New York Bight inner
  continental shelf, ASLO Aquatic Sciences Meeting,
  Albuquerque, NM, February 2001.

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Anticipated Publications

• Chang, G. C. and T. D. Dickey, Optical influences
  on solar transmission and radiant heating rate in
  coastal waters, in prep for JGR.
• Chang, G. C. and T. D. Dickey, Interdisciplinary
  sampling strategies for detection and
  characterization of harmful algal blooms, in prep
  for HABWatch book.
• Chang, G. and T. Dickey, Optical Methods for
  Interdisciplinary Research in the Coastal Ocean,
  in prep for Recent Research Developments in
  Optics, A. Gayathri, ed .
• Chang, G., R. Gould, R. Arnone, and T. Dickey,
  Comparisons between SeaWiFS, MODIS, and in situ
  measurements of remote sensing reflectance and
  bio-optical properties, for Optics Express.
• Dickey, T., M. Lewis, and G. Chang, Bio-optical
  oceanography Recent advances and future
  directions using global remote sensing and in
  situ observations, in prep for Rev. of Geophys.
• Manov, D. V., T. D. Dickey, and G. C. Chang,
  Methods for Reducing Biofouling of Moored Optical
  Sensors, in prep for JAOT.

Upcoming Conferences

• HABWatch Workshop, Villefranche-Sur-de-Mer,
  France, June 11-21, 2003.
• Chang, G. C. and T. D. Dickey, Variability of
  solar transmission and radiant heating rate in
  the coastal ocean optical impacts, submitted to
  IUGG Meeting, Sapporo, Japan, June - July 2003.

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HyCODE Spin-Offs

• NOPP MOSEAN project (with Casey Moore, Al Hansen,
  and Dave Karl) Shallow water mooring in the
  Santa Barbara Channel to
• (1) Develop and test new optical and chemical
  sensors
• (2) Develop and test new biofouling techniques
• (3) Investigate HABs optical identification
  methods, characteristics of their formation and
  cessation, etc.
• (4) Study scattering properties of storm runoff
  / sediment resuspension (Santa Clara and Ventura
  River plumes)

Do I win the award for shortest presentation (not
presenter) again?