Chlorophyll aalgorithms for oligotrophic oceans: A novel approach based on three‐band reflectance difference

[1] A new empirical algorithm is proposed to estimate surface chlorophyll a (Chl) concentrations in the global ocean for Chl ≤ 0.25 mg m−3(∼78% of the global ocean area). The algorithm is based on a color index (CI), defined as the difference between remote-sensing reflectance (Rrs, sr−1) in the green and a reference formed linearly between Rrsin the blue and red. For low-Chl waters, in situ data showed a tighter (and therefore better) relationship between CI and Chl than between traditional band ratios and Chl, which was further validated using global data collected concurrently by ship-borne and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer (MODIS)/Aqua instruments. Model simulations showed that for low-Chl waters, compared with the band-ratio algorithm, the CI-based algorithm (CIA) was more tolerant to changes in chlorophyll-specific backscattering coefficient and performed similarly for different relative contributions of nonphytoplankton absorption. Simulations using existing atmospheric correction approaches further demonstrated that the CIA was much less sensitive than band-ratio algorithms to various errors induced by instrument noise and imperfect atmospheric correction (including sun glint and whitecap corrections). Image and time series analyses of SeaWiFS and MODIS/Aqua data also showed improved performance in terms of reduced image noise, more coherent spatial and temporal patterns, and better consistency between the two sensors. The reduction in noise and other errors is particularly useful to improve the detection of various ocean features such as eddies. Preliminary tests over Medium-Resolution Imaging Spectrometer and Coastal Zone Color Scanner data indicate that the new approach should be generally applicable to all past, current, and future ocean color instruments.

[1]  Menghua Wang,et al.  Seawifs Postlaunch Calibration and Validation Analyses , 2013 .

[2]  Chuanmin Hu,et al.  A tale of two eddies: Diagnosing coherent eddies through acoustic remote sensing , 2011 .

[3]  Giuseppe Zibordi,et al.  An inherent-optical-property-centered approach to correct the angular effects in water-leaving radiance. , 2011, Applied optics.

[4]  Chuanmin Hu,et al.  Tracking the Deepwater Horizon Oil Spill: A Modeling Perspective , 2011 .

[5]  Chuanmin Hu,et al.  An empirical approach to derive MODIS ocean color patterns under severe sun glint , 2011 .

[6]  Ziauddin Ahmad,et al.  New aerosol models for the retrieval of aerosol optical thickness and normalized water-leaving radiances from the SeaWiFS and MODIS sensors over coastal regions and open oceans. , 2010, Applied optics.

[7]  H. Dierssen.  Perspectives on empirical approaches for ocean color remote sensing of chlorophyll in a changing climate , 2010, Proceedings of the National Academy of Sciences.

[8]  S. Maritorena,et al.  Merged satellite ocean color data products using a bio-optical model: Characteristics, benefits and issues , 2010 .

[9]  P Jeremy Werdell,et al.  Estimation of near-infrared water-leaving reflectance for satellite ocean color data processing. , 2010, Optics express.

[10]  W. Gregg,et al.  Improving the consistency of ocean color data: A step toward climate data records , 2010 .

[11]  R. Arnone,et al.  Uncertainties of Optical Parameters and Their Propagations in an Analytical Ocean Color Inversion Algorithm , 2010 .

[12]  Michael S Twardowski,et al.  Angular shape of the oceanic particulate volume scattering function in the backward direction. , 2009, Applied optics.

[13]  Chuanmin Hu.  A novel ocean color index to detect floating algae in the global oceans , 2009 .

[14]  C. McClain.  A decade of satellite ocean color observations. , 2009, Annual review of marine science.

[15]  T. Wynne,et al.  An evaluation of remote sensing techniques for enhanced detection of the toxic dinoflagellate, Karenia brevis , 2009 .

[16]  M. Kahru,et al.  ADEOS-II/GLIの生物光学アルゴリズム , 2009 .

[17]  Menghua Wang,et al.  Remote Sensing of Inherent Optical Properties : Fundamentals , 2009 .

[18]  A. Morel.  Are the empirical relationships describing the bio-optical properties of case 1 waters consistent and internally compatible? , 2009 .

[19]  Catherine A. Brown,et al.  The origin and global distribution of second order variability in satellite ocean color and its potential applications to algorithm development , 2008 .

[20]  Melanie Abecassis,et al.  Ocean's least productive waters are expanding , 2008 .

[21]  Rasmus Fensholt,et al.  Remote Sensing , 2008, Encyclopedia of GIS.

[22]  B. Franz,et al.  Examining the consistency of products derived from various ocean color sensors in open ocean (Case 1) waters in the perspective of a multi-sensor approach , 2007 .

[23]  Francesco d'Ovidio,et al.  Stirring of the northeast Atlantic spring bloom: A Lagrangian analysis based on multisatellite data , 2007 .

[24]  B. Franz,et al.  Sensor-independent approach to the vicarious calibration of satellite ocean color radiometry. , 2007, Applied optics.

[25]  David McKee,et al.  Optical water type discrimination and tuning remote sensing band-ratio algorithms: Application to retrieval of chlorophyll and Kd(490) in the Irish and Celtic Seas , 2007 .

[26]  F. Muller‐Karger,et al.  On the absorption of light in the Orinoco River plume , 2007 .

[27]  H. Claustre,et al.  Optical properties of the “clearest” natural waters , 2007 .

[28]  W. Gregg.  Reports of the International Ocean-Colour Coordinating Group , 2007 .

[29]  Chuanmin Hu,et al.  Validation of SeaWiFS chlorophyll a concentrations in the Southern Ocean: A revisit , 2006 .

[30]  David A. Siegel,et al.  Climate-driven trends in contemporary ocean productivity , 2006, Nature.

[31]  Kendall L. Carder,et al.  Ocean color reveals phase shift between marine plants and yellow substance , 2006, IEEE Geoscience and Remote Sensing Letters.

[32]  Maureen A. Kennelly,et al.  What Have We Learned About Ocean Variability from Satellite Ocean Color Imagers , 2006 .

[33]  B. Kumari.  Comparison of high performance liquid chromatography and fluorometric ocean colour pigments , 2005 .

[34]  P. J. Werdell,et al.  An improved in-situ bio-optical data set for ocean color algorithm development and satellite data product validation , 2005 .

[35]  R. Evans,et al.  Bridging ocean color observations of the 1980s and 2000s in search of long-term trends , 2005 .

[36]  J. Gower,et al.  Detection of intense plankton blooms using the 709 nm band of the MERIS imaging spectrometer , 2005 .

[37]  C. McClain,et al.  Recent trends in global ocean chlorophyll , 2005 .

[38]  W. Gregg,et al.  Global and regional evaluation of the SeaWiFS chlorophyll data set , 2004 .

[39]  Stanford B. Hooker,et al.  An overview of the SeaWiFS project and strategies for producing a climate research quality global ocean bio-optical time series , 2004 .

[40]  Charles R. McClain,et al.  Subtropical Gyre Variability Observed by Ocean Color Satellites , 2004 .

[41]  H. Claustre,et al.  The Many Shades of Ocean Blue , 2003, Science.

[42]  F. Muller‐Karger,et al.  Comparison of ship and satellite bio-optical measurements on the continental margin of the NE Gulf of Mexico , 2003 .

[43]  Robert Frouin,et al.  Seasonal and inter‐annual variability of particulate organic matter in the global ocean , 2002 .

[44]  Stéphane Maritorena,et al.  Optimization of a semianalytical ocean color model for global-scale applications. , 2002, Applied optics.

[45]  K. Stamnes,et al.  Role of oceanic air bubbles in atmospheric correction of ocean color imagery. , 2002, Applied optics.

[46]  G. Zibordi,et al.  An Evaluation of Above- and In-Water Methods for Determining Water-Leaving Radiances , 2002 .

[47]  M. Vernet,et al.  Glacial meltwater dynamics in coastal waters west of the Antarctic peninsula , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[48]  S. Bailey,et al.  Correction of Sun glint Contamination on the SeaWiFS Ocean and Atmosphere Products. , 2001, Applied optics.

[49]  F. Muller‐Karger,et al.  How precise are SeaWiFS ocean color estimates? Implications of digitization-noise errors , 2001 .

[50]  S. Maritorena,et al.  Bio-optical properties of oceanic waters: A reappraisal , 2001 .

[51]  Sonoyo Mukai,et al.  Inverse problems in the atmosphere-ocean system: estimation of aerosol characteristics and phytoplankton distribution , 2000, Appl. Math. Comput..

[52]  K. Carder,et al.  Band-ratio or spectral-curvature algorithms for satellite remote sensing? , 2000, Applied optics.

[53]  Prieur,et al.  Analysis of variations in ocean color’ , 2000 .

[54]  J R Zaneveld,et al.  In situ determination of the remotely sensed reflectance and the absorption coefficient: closure and inversion. , 1999, Applied optics.

[55]  K. Carder,et al.  Semianalytic Moderate‐Resolution Imaging Spectrometer algorithms for chlorophyll a and absorption with bio‐optical domains based on nitrate‐depletion temperatures , 1999 .

[56]  M. Kahru,et al.  Empirical chlorophyll algorithm and preliminary SeaWiFS validation for the California Current , 1999 .

[57]  Xiaodong Zhang,et al.  Influence of bubbles on scattering of light in the ocean. , 1998, Applied optics.

[58]  E. Fry,et al.  Absorption spectrum (380-700 nm) of pure water. II. Integrating cavity measurements. , 1997, Applied optics.

[59]  H. Gordon.  Atmospheric correction of ocean color imagery in the Earth Observing System era , 1997 .

[60]  Ricardo M Letelier,et al.  An analysis of chlorophyll fluorescence algorithms for the moderate resolution imaging spectrometer (MODIS) , 1996 .

[61]  Robert Frouin,et al.  Spectral reflectance of sea foam in the visible and near-infrared: In situ measurements and remote sensing implications , 1996 .

[62]  H. Claustre,et al.  Variability in the chlorophyll‐specific absorption coefficients of natural phytoplankton: Analysis and parameterization , 1995 .

[63]  Janet W. Campbell,et al.  The lognormal distribution as a model for bio‐optical variability in the sea , 1995 .

[64]  H. Gordon,et al.  Influence of oceanic whitecaps on atmospheric correction of ocean-color sensors. , 1994, Applied optics.

[65]  Menghua Wang,et al.  Retrieval of water-leaving radiance and aerosol optical thickness over the oceans with SeaWiFS: a preliminary algorithm. , 1994, Applied optics.

[66]  B Gentili,et al.  Diffuse reflectance of oceanic waters. II Bidirectional aspects. , 1993, Applied optics.

[67]  Stanford B. Hooker,et al.  An overview of the SeaWiFS Project , 1993 .

[68]  L. Prieur,et al.  A three-component model of ocean colour and its application to remote sensing of phytoplankton pigments in coastal waters , 1989 .

[69]  J. Brooks,et al.  Errors associated with the standard fluorimetric determination of chlorophylls and phaeopigments , 1985 .

[70]  H. Gordon,et al.  Remote Assessment of Ocean Color for Interpretation of Satellite Visible Imagery: A Review , 1983 .

[71]  J. W. Campbell,et al.  Basis for spectral curvature algorithms in remote sensing of chlorophyll. , 1983, Applied optics.

[72]  Howard R. Gordon,et al.  Remote Assessment of Ocean Color for Interpretation of Satellite Visible Imagery , 1983, Lecture Notes on Coastal and Estuarine Studies.

[73]  H. Gordon,et al.  Clear water radiances for atmospheric correction of coastal zone color scanner imagery. , 1981, Applied optics.

[74]  S. Tassan.  The Influence of Wind in the Remote Sensing of Chlorophyll in the Sea , 1981 .

[75]  H. Gordon,et al.  Remote sensing optical properties of a stratified ocean: an improved interpretation. , 1980, Applied optics.

[76]  Didier Tanré,et al.  An algorithm for remote sensing of water color from space , 1980 .

[77]  E. Baker,et al.  Upwelled spectral radiance distribution in relation to particulate matter in sea water , 1980 .

[78]  André Morel,et al.  In-water and remote measurements of ocean color , 1980 .

[79]  P. Deschamps,et al.  Airborne remote sensing of chlorophyll content under cloudy sky as applied to the tropical waters in the Gulf of Guinea , 1978 .

[80]  L. Prieur,et al.  Analysis of variations in ocean color1 , 1977 .

[81]  W. Hovis,et al.  Remote Sensing of Ocean Color , 1977 .

[82]  A. Morel.  Optical properties of pure water and pure sea water , 1974 .

[83]  J. Millard,et al.  Remote sensing of chlorophyll and temperature in marine and fresh waters , 1973 .

[84]  C. Lorenzen,et al.  Spectra of Backscattered Light from the Sea Obtained from Aircraft as a Measure of Chlorophyll Concentration , 1970, Science.