Publications by authors named "Peter Minnett"

A water-soluble thermochromic molecular switch with spectrally resolved fluorescence in its two interconvertible states can be assembled in three synthetic steps by integrating a fluorescent coumarin chromophore, a hydrophilic oligo(ethylene glycol) chain, and a switchable oxazole heterocycle in the same covalent skeleton. Measurements of its two emissions in separate detection channels of a fluorescence microscope permit the noninvasive and ratiometric sensing of temperature at the micrometer level with millisecond response in aqueous solutions and within hydrogel matrices. The ratiometric optical output of this fluorescent molecular switch overcomes the limitations of single-wavelength fluorescent probes and enables noninvasive temperature mapping at length scales that are not accessible to conventional thermometers based on physical contact.

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We present a simple algorithm to identify Karenia brevis blooms in the Gulf of Mexico along the west coast of Florida in satellite imagery. It is based on an empirical analysis of collocated matchups of satellite and in situ measurements. The results of this Empirical Approach is compared to those of a Bio-optical Technique - taken from the published literature - and the Operational Method currently implemented by the NOAA Harmful Algal Bloom Forecasting System for K.

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In a continuing effort to develop suitable methods for the surveillance of Harmful Algal Blooms (HABs) of Karenia brevis using satellite radiometers, a new multi-algorithm method was developed to explore whether improvements in the remote sensing detection of the Florida Red Tide was possible. A Hybrid Scheme was introduced that sequentially applies the optimized versions of two pre-existing satellite-based algorithms: an Empirical Approach (using water-leaving radiance as a function of chlorophyll concentration) and a Bio-optical Technique (using particulate backscatter along with chlorophyll concentration). The long-term evaluation of the new multi-algorithm method was performed using a multi-year MODIS dataset (2002 to 2006; during the boreal Summer-Fall periods - July to December) along the Central West Florida Shelf between 25.

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Oxygen-based productivity and respiration rates were determined in West Florida coastal waters to evaluate the proportion of community respiration demands met by autotrophic production within a harmful algal bloom dominated by . The field program was adaptive in that sampling during the 2006 bloom occurred where surveys by the Florida Wildlife Research Institute indicated locations with high cell abundances. Net community production (NCP) rates from light-dark bottle incubations during the bloom ranged from 10 to 42 µmole O L day with highest rates in bloom waters where abundances exceeded 10 cells L.

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Coupled physical-biological models are capable of linking the complex interactions between environmental factors and physical hydrodynamics to simulate the growth, toxicity and transport of infectious pathogens and harmful algal blooms (HABs). Such simulations can be used to assess and predict the impact of pathogens and HABs on human health. Given the widespread and increasing reliance of coastal communities on aquatic systems for drinking water, seafood and recreation, such predictions are critical for making informed resource management decisions.

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The surface-leaving radiance model developed in Part I [Appl. Opt.47,3701 (2008)] is validated against an exhaustive set of Fourier transform spectrometer field observations acquired at sea.

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Although published sea surface infrared (IR) emissivity models have gained widespread acceptance for remote sensing applications, discrepancies have been identified against field observations obtained from IR Fourier transform spectrometers at view angles approximately > 40 degrees. We therefore propose, in this two-part paper, an alternative approach for calculating surface-leaving IR radiance that treats both emissivity and atmospheric reflection in a systematic yet practical manner. This first part presents the theoretical basis, development, and computations of the proposed model.

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Spectral statistical-analysis techniques were developed and applied to high-spectral-resolution infrared measurements of the sea surface. The effective incidence angle of a ship-borne instrument in typical at-sea conditions was found to introduce errors of up to 0.7 K in sea-surface temperature retrievals at a 55 degrees view angle.

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