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This dataset contains the dissolved organic matter (DOM) quantification and optical characterisation results from a KOSMOS mesocosm experiment carried out in the framework of the Ocean Artificial Upwelling project. The experiment was carried out in the autumn of 2018 in the oligotrophic waters of Gran Canaria. During the 39 days of experiment nutrient-rich deep water was added to the mesocosms in two modes (singular vs recurring additions), with four levels of intensity. Dissolved organic carbon, nitrogen and phosphorus were quantified with a Shimadzu TOC-5000 and a QuAAtro AutoAnalyzer. The absorption and fluorescence proprieties of DOM were determined making use of an Ocean Optics USB2000+UV-VIS-ES Spectrometer and a Jobin Yvon Horiba Fluoromax-4 spectrofluorometer, respectively. The aim of this dataset was to study the effect of artificial upwelling on the dissolved organic matter pool and its potential implications for carbon sequestration.

This dataset contains the results of the characterisation of the prokaryotic community by flow cytometry and tritiated leucine incorporation from the MAFIA cruise (Migrants and Active Flux In the Atlantic ocean). Samples were collected in the tropical and subtropical Atlantic during the MAFIA cruise (April 2015) on board the BIO Hespérides. Seawater samples were collected at 13 stations (from the Brazilian coast to the Canary Islands), from the surface down to 3500 m, using a General Oceanics oceanographic rosette equipped with 24 l PVC Niskin bottles. Abundance and cell characteristics (high nucleic acid content fraction, cell volume, viability) were based on measurements performed with a FACSCalibur (Becton-Dickinson) flow cytometer. Leucine incorporation rates were estimated with tritiated leucine (Kirchman et al. 1985) using centrifugation and filtration methods (Smith and Azam 1992). Integrated or average values of variables were estimated for the epipelagic (0-200 m), mesopelagic (200-1000 m) and bathypelagic (1000-3000 m) layers, based on an interpolated grid estimated with DIVA. The aim of this dataset was to estimate the influence of surface productivity on the standing stock, characteristics and activity (as leucine incorporation) of prokaryotes across the water column.

Here we present calcareus nannofossil and colour datasets from the hemipelagic lower Ypresian Arnakatxa section (Basque-Cantabrian basin, western Pyrenees). The Arnakatxa coastal cliffs, which constitute the present study area, are located approximately 15 km northwest of Bilbao (43°23'34.4N, 2°59'24.2W, altitude 0 m). The expanded hemiplegic succession offered a potentially valuable orbitally paced geological record. Sampling was carried out in 2015. For the study of calcareous nannofossils 65 hand samples were collected (average spacing of about 50 cm). For colour analysis, 635 rock-powder samples were collected (average resolution of ~5 cm) using a standard cordless drill with an 8 mm bit. Slides for nannofloral analysis were prepared according to Flores and Sierro (1997), avoiding any mechanical or physical disturbance of the samples that could modify the original fossil assemblages. A Zeiss Axioplan2 petrographic microscope at 1250× magnification was used to analyze the samples. Quantitative analysis was performed by counting at least 300 specimens per sample. Additionally, three random traverses (~9 mm2) were analyzed on each slide in order to detect rare but biostratigraphically significant species. The rock powder samples were stored in transparent antiglare prismatic plastic vials (3 ml) and scanned at high-resolution (600 dpi) using a desktop office scanner in a dark room. The average colour value of a homogeneous rectangular area covering 10-20% of the scanned image of each vial was measured using ImageJ software version 1.50i. Average colour value represents to the mean pixel RGB value of the selected area, which is equivalent to the brightness value. In order to perform a cyclostratigraphic analysis, the colour data series was linearly interpolated and the LOESS regression trend subtracted. The Astrochron code commands used to perform that spectral analysis are herein available.

This dataset reports the isotope composition (carbon and oxygen isotopes) of planktonic foraminiferal (Trilobatus sacculifer), extracted from sediment samples from IODP Site U1459. The analyzed samples have a temporal coverage from the late Pliocene to the early Pleistocene (4 - 2 Ma), and were obtained from the Perth Basin (offshore southwestern Australia). Therewith, Site U1459 is ideally situated to record changes in Leeuwin Current dynamics, and this dataset has been obtained to study Leeuwin Current intensity on orbital glacial-interglacial timescales across the Plio-Pleistocene boundary. All samples were measured using a Finnigan MAT 251 gas isotope ratio mass spectrometer connected to a Kiel III automated carbonate preparation device at the Center for Marine Environmental Sciences (MARUM), between 2018 and 2021.