Category 4 Hurricane Kenneth (HK) experienced unpredicted rapid weakening when it stalled over a cold core eddy (CCE) on 19–20 September 2005, 2800 km SE of Hawaii. Maximum sea surface temperature (SST) cooling of 8–9°C and a minimum aerially averaged SST of 18.3°C (over 8750 km²) characterized its cool wake. A 3‐D mixed‐layer model enabled estimation of enthalpy fluxes (latent and sensible heat), as well as the relative importance of slow translation speed (U_h) compared with the preexisting CCE. As U_h dropped below 1.5 m s⁻¹, enthalpy fluxes became negative, cutting off direct ocean energy flux to HK. Although HK's weakening was attributed to wind shear, our results indicate that slow U_h and consequent intense SST cooling were the main causes. The tropical cyclone‐intensified CCE experienced rapid growth in magnitude (−6 to −40 cm), increased diameter (60 to 350 km), elevated chlorophyll a for 4 months, and 12 month longevity.

The Ocean Color Monitor (OCM) provides radiance measurements in eight visible and near-infrared bands, similar to the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) but with higher spatial resolution. For small- to moderate-sized coastal lakes and estuaries, where the 1 × 1 km spatial resolution of SeaWiFS is inadequate, the OCM provides a good alternative because of its higher spatial resolution (240 × 360 m) and an exact repeat coverage of every two days. This paper describes a detailed step-by-step atmospheric correction procedure for OCM data applicable to coastal Case 2 waters. This development was necessary as accurate results could not be obtained for our Case 2 water study area in coastal Louisiana with OCM data by using existing atmospheric correction software packages. In addition, since OCM-retrieved radiances were abnormally low in the blue wavelength region, a vicarious calibration procedure was developed. The results of our combined vicarious calibration and atmospheric correction procedure for OCM data were compared with the results from the SeaWiFS Data Analysis System (SeaDAS) software package outputs for SeaWiFS and OCM data. For Case 1 waters, our results matched closely with SeaDAS results. For Case 2 waters, our results demonstrated closure with in situ radiometric measurements, while SeaDAS produced negative normalized water leaving radiance (_nL_w) and remote sensing reflectance (R_rs). In summary, our procedure resulted in valid _nL_w and R_rs values for Case 2 waters using OCM data, providing a reliable method for retrieving useful _nL_w and R_rs values which can be used to develop ocean color algorithms for in-water substances (e.g., pigments, suspended sediments, chromophoric dissolved organic matter, etc.) at relatively high spatial resolution in regions where other software packages and sensors such as SeaWiFS and Moderate Resolution Imaging Spectrometer (MODIS) have proven unsuccessful. The method described here can be applied to other sensors such as OCM-2 or other Case 2 water areas.

The processes by which oil-material appears suspended in the water column or becomes deposited on the sea floor is conventionally attributed to its attachment to marine solid particles. Since the 2010 Gulf oil spill, a significant volume has remained unaccounted for. The fraction volume of oil sinking resulting from dissolution of its lighter components is the subject of this work. An experimental study and theoretical development for the combined processes of oil-droplet dissolution/sinking (named SOLUTE-SINK) is based on a conceptual binary-component model for crude oil. The experiments were on buoyant pseudo-oils, a two-component (A and B) miscible hydrocarbon mixture formulated from a less-dense-than-water liquid hydrocarbon (Component A) and a more-dense-than-water hydrocarbon-like chemical (Component B). These were used in proof-of-concept experiments. A single, buoyant liquid drop surrounded by water was constrained from floating to the surface in a laboratory-scale microcosm dissolution tank. It was placed inside an inverted and submerged Petri dish so evaporation was not possible and weathering occurred by dissolution only. The heavier-than-water Component B was much less soluble; during the experiment, Component-A dissolution losses resulted in droplet sinking. This established proof-of-concept and the observed time period provided key data supporting the proposed oil binary-model theory. Experiments were performed with four binary chemical mixtures, each replicated 5–7 times. The dissolution time periods for achieving buoyancy inversion (i.e., sinking droplet) ranged from 2 to 4 days with the kinetics parameter dependent on the solubility of Component A. Concentration and bulk density measurements tracked the theoretical time-series behavior of the proposed model equations. Direct mathematical coupling the dissolution/buoyancy loss process for single liquid droplet in the water column is an original contribution of this work. In knowing the initial drop-size distribution, the field of oil-spill modeling is provided with an algorithm forecasting four oil-material produced fractions: dissolved, floating, suspended, and sinking. The SOLUTE-SINK model will find applications for deep-water blowout ejected droplets (constrained to dissolution weathering only) as well as breaking-wave-produced droplets for sea surface spills. In addition, it will aid the development of a laboratory method for the oil dissolution process.