If Marine Protected Areas (MPAs) are to aid in protecting and conserving marine ecosystems in the face of extensive and severe impacts of human activities, underpinning scientific knowledge and understanding of MPAs are imperative. This study aims to describe and evaluate phytoplankton dynamics in a pelagic Mediterranean MPA (The Pelagos International Marine Mammals Sanctuary) in the northwestern Mediterranean Sea as a means to understand better the spatial and temporal distribution of basal ecosystem resources. Ocean colour data collected by orbital remote sensing (Sea-viewing Wide Field-of-view Sensor [SeaWiFS] data) were analysed to elucidate spatial and temporal variations in the concentration of chlorophyll-like pigments (chl). Mean chl images were generated for consecutive 10-day periods, to provide quasi-continuous coverage of the study area, combined with a Principal Component Analysis and analysis of a time series (1998-2004). The chl surface patterns traced seasonal upwelling events recurring annually, demonstrating the critical role of physical oceanography in sustaining the food web of the PelagosSanctuary. Phytoplankton blooms, however, differ in terms of peak timing, spatial distribution and chl concentration, due in part to the influence of broad-scale environmental factors that are beyond direct and regional control. Further research is needed to elucidate the relationship between the biomass of primary and secondary producers to understand better the implications of phytoplankton biomass distribution in space and time for charismatic and protected biota such as cetaceans. (C) 2017 Elsevier B.V. All rights reserved.

Measurements of sea surface temperature at the skin interface (SSTskin) made by an Infrared Sea Surface Temperature Autonomous Radiometer (ISAR) have been used for a number of years to validate satellite sea surface temperature (SST), especially high-accuracy observations such as made by the Advanced Along-Track Scanning Radiometer (AATSR). The ISAR instrument accuracy for measuring SSTskin is +/- 0.1K (Donlon et al.), but to satisfy Quality Assurance Framework for Earth Observation (QA4EO) principles and metrological standards (Joint Committee for Guides in Metrology), an uncertainty model is required. To develop the ISAR uncertainty model, all sources of uncertainty in the instrument are analyzed and an uncertainty value is assigned to each component. Finally, the individual uncertainty components are propagated through the ISAR SSTskin retrieval algorithm to estimate a total uncertainty for each measurement. The resulting ISAR uncertainty model applied to a 12-yr archive of SSTskin measurements from the Bay of Biscay shows that 77.6% of the data are expected to be within 60.1K and a further 17.2% are within 0.2 K.

Quasi-operational shipborne radiometers provide a fiducial reference measurement (FRM) for satellite validation of satellite sea surface skin temperature (SSTskin) retrievals. External reference blackbodies are required to verify the performance and to quantify the accuracy of the radiometer calibration system. They provide a link in an unbroken chain of comparisons between the shipborne radiometer and a traceable reference standard. A second-generation water bath blackbody reference radiance source has been developed for this purpose. The second generation Concerted Action for the Study of the Ocean Thermal Skin (CASOTS-II) blackbody has a 110-mm-diameter aperture cylinder-cone geometry coated with NEXTEL suede 3103 paint. Interchangeable aperture stops reduce the cavity aperture diameter and minimize stray radiation. Monte Carlo modeling techniques show the effective emissivity of the cavity to be >0.9999 (aperture < 30 mm). The cavity is immersed in a water bath that is vigorously stirred using a pump that slowly heats the water bath at a mean rate of ~0.6 K h(-1). The temperature of the water bath is measured using a thermometer traceable to the International System of Units (SI) standards. The worst-case radiance temperature of the CASOTS-II blackbody system is traceable to the SI with an uncertainty of 58 mK (millikelvin). When operating under typical laboratory conditions using an aperture of 40 mm, the uncertainty is 16 mK. An intercomparison with the U.K. National Physical Laboratory Absolute Measurements of Blackbody Emitted Radiance (AMBER) reference radiometer found no significant differences within 75 mK (110-mm aperture) or 50 mK (40-mm aperture), which is the combined uncertainty of the comparison and the reference standard for SI traceability of ISAR radiometer SSTskin records used for satellite SST validation. Applications of the CASOTS-II blackbody to monitor the calibration of shipborne radiometers are described and measurement protocols are proposed.