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Carbon export (from the epipelagic towards the mesopelagic zone) and sequestration (from the mesopelagic towards the bathypelagic zone) in the ocean are reviewed. Particulate organic carbon (POC) flux, and active flux due to migrant zooplankton and micronekton are shown from the epipelagic to the mesopelagic zone, and from the latter to the bathypelagic zone. Values towards the meso- and bathypelagic zones are compared in oligotrophic and productive systems. Zooplankton and prokaryote respiration in the meso- and bathypelagic zones of the ocean are also reviewed for oligotrophic and productive systems. Values were integrated over a depth layer and are given as the flux or respiration under one square meter (in g/m**2/a) between e.g. 100 m and 1000 m depth.

The Tara Oceans Expedition (2009-2013) sampled the world oceans on board a 36 m long schooner, collecting environmental data and organisms from viruses to planktonic metazoans for later analyses using modern sequencing and state-of-the-art imaging technologies. Tara Oceans Data are particularly suited to study the genetic, morphological and functional diversity of plankton. The present data set provides raw validated data of continuous measurements made with an Aquatic Laser Fluorescence Analyzer (ALFA) (Chekalyuk et al., 2014), connected in-line to the TARA flow through system during 2013. The ALFA instrument provides dual-wavelength excitation (405 and 514 nm) of laser-stimulated emission (LSE) for spectral and temporal analysis. It offers in vivo fluorescence assessments of phytoplankton pigments, biomass, photosynthetic yield (Fv/Fm), phycobiliprotein (PBP)-containing phytoplankton groups, and chromophoric dissolved organic matter (CDOM) (Chekalyuk and Hafez, 2008; 2013A). Spectral deconvolution (SDC) is used to assess the overlapped spectral bands of aquatic fluorescence constituents and water Raman scattering (R). The Fv/Fm measurements are spectrally corrected for non-chlorophyll fluorescence background produced by CDOM and other constituents (Chekalyuk and Hafez, 2008). The sensor was cleaned weakly following the manufacturer recommended protocol.

Hyperspectral optical data for satellite remote sensing

The Tara Oceans Expedition (2009-2013) sampled the world oceans on board a 36 m long schooner, collecting environmental data and organisms from viruses to planktonic metazoans for later analyses using modern sequencing and state-of-the-art imaging technologies. Tara Oceans Data are particularly suited to study the genetic, morphological and functional diversity of plankton. During the entire expedition (2009-2013), underway measurements were obtained from a meteorological station (BATOS), a thermosalinograph (TSG, SBE 45), a Fast Repetition Rate Flurometer (FRRF, LIFT-FRR01), and a spectrophotometer (WETLabs AC-S). In 2013 underway measurements were enhanced by adding a Photosynthetically Available Radiation (PAR) sensor (QCP2350, Biospherical Instruments, Inc.), a laser spectrofluorometer (WETLabs ALFA, Chekalyuk et al., 2012) that replaced the FRRF, a spectral backscattering sensor (WETLabs Eco-bb3), a pCO2 sensor (ProOceanus CO2-Pro), a pH sensor (Satlantic, SeaFET) and a particle imaging system triggered by chlorophyll-a fluorescence (a prototype of McLane Research Laboratories' Imaging FlowCytobot, Sosik Lab, WHOI). Discrete measurements of CDOM absorption measurements were made using an Ultrapath (WPI Inc.) to calibrate the in-line AC-S. Hence the AC-S was also used to provide CDOM absorption in addition to particulate matter properties. The present dataset contains surface water data measured during the 2009-2012 campaigns of the Tara Oceans Expedition. Latitude and Longitude were obtained from TSG data. The time stamp of this data set is harmonised with that of other underway data in this collection.

Light emerging from natural water bodies and measured by remote sensing radiometers contains information about the local type and concentrations of phytoplankton, non-algal particles and colored dissolved organic matter in the underlying waters. An increase in spectral resolution in forthcoming satellite and airborne remote sensing missions is expected to lead to new or improved capabilities to characterize aquatic ecosystems. Such upcoming missions include NASA's Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Mission; the NASA Surface Biology and Geology observable mission; and NASA Airborne Visible / Infrared Imaging Spectrometer (AVIRIS) - Next Generation airborne missions. In anticipation of these missions, we present an organized dataset of geographically diverse, quality-controlled, high spectral resolution inherent and apparent optical property (IOP/AOP) aquatic data. The data are intended to be of use to increase our understanding of aquatic optical properties, to develop aquatic remote sensing data product algorithms, and to perform calibration and validation activities for forthcoming aquatic-focused imaging spectrometry missions. The dataset is comprised of contributions from several investigators and investigating teams collected over a range of geographic areas and water types, including inland waters, estuaries and oceans. Specific in situ measurements include coefficients describing particulate absorption, particulate attenuation, non-algal particulate absorption, colored dissolved organic matter absorption, phytoplankton absorption, total absorption, total attenuation, particulate backscattering, and total backscattering, as well as remote sensing reflectance, and irradiance reflectance. Supplement to: Casey, Kimberly A; Rousseaux, Cecile S; Gregg, Watson W; Boss, Emmanuel; Chase, Alison P; Craig, Susanne E; Mouw, Colleen B; Reynolds, Rick A; Stramski, Dariusz; Ackleson, Steven G; Bricaud, Annick; Schaeffer, Blake; Lewis, Marlon R; Maritorena, Stéphane (2020): A global compilation of in situ aquatic high spectral resolution inherent and apparent optical property data for remote sensing applications. Earth System Science Data, 12(2), 1123-1139 Version comment:2020-05-20: Version 2 (xlsx files updated)

Developing and validating data records from operational ocean color satellite instruments requires substantial volumes of high quality in situ data. In the absence of broad, institutionally supported field programs, organizations such as the NASA Ocean Biology Processing Group seek opportunistic datasets for use in their operational satellite calibration and validation activities. The publicly available, global biogeochemical dataset collected as part of the two and a half year Tara Oceans expedition provides one such opportunity. We showed how the inline measurements of hyperspectral absorption and attenuation coefficients collected onboard the R/V Tara can be used to evaluate near-surface estimates of chlorophyll-a, spectral particulate backscattering coefficients, particulate organic carbon, and particle size classes derived from the NASA Moderate Resolution Imaging Spectroradiometer onboard Aqua (MODISA). The predominant strength of such flow-through measurements is their sampling rate-the 375 days of measurements resulted in 165 viable MODISA-to-in situ match-ups, compared to 13 from discrete water sampling. While the need to apply bio-optical models to estimate biogeochemical quantities of interest from spectroscopy remains a weakness, we demonstrated how discrete samples can be used in combination with flow-through measurements to create data records of sufficient quality to conduct first order evaluations of satellite-derived data products. Given an emerging agency desire to rapidly evaluate new satellite missions, our results have significant implications on how calibration and validation teams for these missions will be constructed.