putting the puzzle together: connecting the hypersas with brevebuster absorbance spectra,...
TRANSCRIPT
Putting the puzzle together: Connecting the HyperSAS with BreveBuster absorbance spectra, fluorometer, extracted chlorophyll and MODIS data. Blake A. Schaeffer, D.
Kamykowski, J. M. Morrison, S. Banks, A. McCulloch, and W. V. Sweet
Introduction
• The Galapagos harbors such great diversity because of its positioning in a complex transition zone between tropical, subtropical and upwelled waters.
• Only place in the world where hammerhead sharks, penguins, and sealions co-exist on the same sub-tidal reef.
Introduction
• Three major current systems influence the Galapagos.
• Cool southern currents from the Humboldt (Peru) system influencing the southern islands.
• Warmer Panama currents that influence the northern islands.
• Strong, large-scale Equatorial Undercurrent (EUC) upwelling in the western archipelago.
Focus
• The EUC is the major oceanographic feature affecting production in the Galápagos, and is strongly associated with local biogeography of marine species.
• Galápagos biogeography/marine ecosystem heterogeneity is a function of oceanographic patterning over small spatial, seasonal and inter-annual scales.
Goals
• Hyperspectral information combined with BreveBuster absorbance spectra, fluorometer, extracted chlorophyll and MODIS data will identify variability of phytoplankton biomass throughout the Galapagos.
• Hyperspectral information will elucidate phytoplankton taxonomy of the Galapagos with the support of HPLC pigment analysis, particulate absorption spectra and BreveBuster data.
Methods
• Sierra Negra• 70 hydrographic
stations• 12 days
Methods
• Phytoplankton – 20 m net– 20 meters depth
• Filtration– Surface only– Extracted chlorophyll a– Particulate absorption
spectra
• Seapoint FL– Top 2 meters bin average
Seapoint Fluorometer
Phytoplankton tows
Filtration
HyperSAS
Methods• MODIS
– Chlorophyll a– SeaDAS v 4.9
• BreveBuster– In situ spectrometer– Phytoplankton class
spectral libraries– Day and night travel
• HyperSAS– 166-channel MiniSpec
radiance and irradiance sensors
– Day travel only
BreveBuster – Mote Marine Aquarium
March 2005Chlorophyll a
(g/L)
084 089
Wet season
Panama current
dominates.
November 2005Chlorophyll a
(g/L)
324 347
Transitionfrom garua
(dry) to wet
season.
Panama current replaces
Peru current.
Transition from wet to garua
(dry).
June 2006Chlorophyll a
(g/L)
190181
MODIS chlorophyll a shows similar trends and range to Seapoint FL chlorophyll a.
MODIS chlorophyll a show similartrends to extracted chlorophyll a, but less agreement in range.
HyperSAS identifies variability not present in MODIS chlorophyll a.
Remote sensing reflectance
Chlo
rophyll
a
Phyco
cyanin
Chlo
rophyll
a
Caro
tenoid
s
Particulate absorption
Particulate absorption spectra
BreveBuster Phytoplankton Class ID
BreveBuster Phytoplankton Class ID
Phytoplankton Tows
Future work• HPLC pigment analysis
– Chemtax
• Particulate absorption spectral library
• Remote sensing reflectance 4th derivative analysis
• HyperSAS phytoplankton class spectral library
• Poster: 4.28-P Today 12:00 – Seasonality of
phytoplankton distributions in the Galapagos Marine Reserve
Chlo
rophyll a
?
Caro
tenoid
s?
Chlo
rophyll a
?
Thank you!
Questions?