Description: Highlights: • Unique 30-years data of currents and temperature below 1000 m in the Madeira Basin. • Inter-decadal and long term changes were examined between 1000 m and the bottom. • Temperature increase by 0.03 ± 0.01 °C/year (1000 m) and 0.02 ± 0.02 °C/year at 1600 m. • No significant changes at 3000 m and 5000 m at long-term scale. • The currents and kinetic energy increased in the entire water column over 30-years. Abstract: Data from the deep-sea mooring Kiel 276 (33 N, 22W), 5300 m water depth in the northeast Atlantic, was used to investigate the temporal variability of temperature and currents below the main thermocline (1000 m, 1600 m, 3000 m, 5000 m) in the 30-year period (between 1980 and 2009). Daily averages were the basis to assess the temperature and currents changes, as well as kinetic energy, from annual to decadal and long-term scales. Below the main thermocline, no seasonal signal was identified for both, temperature and currents, during the 30 years. The record-length linear temperature trends at 1000 m and 1600 m are 0.03 ± 0.01 °C year−1 and 0.02 ± 0.02 °C year−1, respectively. The mean currents also intensified within the decades in the entire water column, and as a consequence, the mean kinetic energy increased. The fluctuating kinetic energy increased on a decadal scale only at 1000 m, as a possible consequence of the increase in the strength of Mediterranean Water lenses (MEDDIES) that crossed the mooring site. During the period 2001–2009, six MEDDIES crossed the Kiel 276 site, in addition to the 10 MEDDIES identified earlier during the previous 20 years, between 1980 and 2000 (Siedler et al., 2005). The integral time scales are of the same order in all depths (between 30 to 40 days), indicating that events occur on similar time scales, with mesoscale signals dominating and being present within the entire water column.

Description: This dataset provides 37 CTD profiles measured on board of the German R/V Sonne (cruise SO269) in the northern South China Sea, under the project SOCLIS – South China Sea Natural Laboratory under Climatic and Anthropogenic Stress, in August and September 2019. The 37 profiles of temperature, salinity, dissolved oxygen, fluorescence, turbidity, surface irradiance (SPAR) and Photosynthetically active radiation (PAR), and sound velocity were measured using a CTD Sea-Bird SBE 911 plus, together with oxygen sensor (SBE 43), PAR sensor (Biospherical, QCP-2350 + QSR-2200), and a fluorometer (WET Labs ECO-FLNTU(RT)D). Additionally, dissolved oxygen, potential temperature and sigma-theta (with reference to the surface) were calculated. The 37 additional CTD files complement the physical oceanography dataset (Waniek et al., 2021).

Description: This dataset provides 131 CTD profiles measured on board of the German R/V Sonne (cruise SO269) in the northern South China Sea, under the project SOCLIS – South China Sea Natural Laboratory under Climatic and Anthropogenic Stress, in August and September 2019. The 131 profiles of temperature, salinity, dissolved oxygen, fluorescence, turbidity, surface irradiance (SPAR) and Photosynthetically active radiation (PAR), and sound velocity were measured using a CTD Sea-Bird SBE 911 plus, together with oxygen sensor (SBE 43), PAR sensor (Biospherical, QCP-2350 + QSR-2200), and a fluorometer (WET Labs ECO-FLNTU(RT)D). Additionally, oxygen saturation, potential temperature and sigma-theta (with reference to the surface) were calculated. The 131 CTD profiles are distributed by 81 stations and aim to study the impact of a growing anthropogenic pressure around the Pearl River Estuary into the northern shelf of the South China Sea towards the deep sea. The dataset was used to study the presence and spatial distribution of natural and synthetic estrogenic compounds and pharmaceutical and personal care products (PPCPs) in the Pearl River Estuary and northern shelf of the South China Sea.

Description: During the cruise POS432 on board the German R/V Poseidon, we collected water with a CTD SBE 11plus equipped with 14 Hydrobios free flow bottles of 10 L each in 15 stations (resulting in almost 100 samples) in the Madeira basin region, Northeast Atlantic. We aimed to study the physical and biogeochemical conditions of the water column along the 22°W meridian, north and south of the Azores Front, in May 2012. We measured concentrations of chlorophyll a, phaeopigments, suspended particulate material (SPM), and nutrients such as nitrate, nitrite, phosphate, and silicate.

Description: This set provides 12 CTD profiles of temperature, salinity, dissolved oxygen, fluorescence, turbidity, and sound velocity measured on board the German R/V Poseidon in September 2013, in the Madeira basin region, Northeast Atlantic. We aimed to study the physical and biogeochemical conditions of the water column along the 22°W meridian, north and south of the Azores Front.

Description: During the cruise POS501 on board the German R/V Poseidon, we measured temperature, salinity, dissolved oxygen, fluorescence, and turbidity on 35 stations in the Madeira Basin, Northeast Atlantic in June 2016. We aimed to study the physical and biogeochemical conditions in the upper 2000 m of the water column in the catchment area of Kiel 276. The CTD stations are distributed along three meridians (23°W, 22°W, 21°W, and 20°W) and between 30° and 37°N to locate the Azores Front. The dissolved oxygen data is noisy below 1700 m Since there was no measurement of dissolved oxygen (Winkler titration) during the cruise, the data cannot be calibrated.

Description: During the cruise POS459 on board the German R/V Poseidon, we collected water with a CTD SBE 11plus equipped with 14 Hydrobios free flow bottles of 10 L each in 9 stations (resulting in almost 100 samples) in the Madeira basin region, Northeast Atlantic. We aimed to study the physical and biogeochemical conditions of the water column along the 22°W meridian, north and south of the Azores Front, in September 2013. We measured concentrations of chlorophyll a, phaeopigments, suspended particulate material (SPM), and nutrients such as nitrate, nitrite, phosphate and silicate. Also, we determined concentrations of particulate organic carbon (POC) and particulate organic nitrogen (PON). The physical oceanography associated with this dataset can be found at https://doi.org/10.1594/PANGAEA.949122. Brief description of the methodology used: - Nitrate, nitrite, phosphate, and silicate were measured by continuous flow analysis. - POC and PON were measured by means of an elemental analyser after filtered with pre-combusted GF/F-filters. - Suspended particulate material (SPM) was determined gravimetrically after pre-combusted and weighted GF/F-filters filtration. - Chlorophyll a and phaeopigments were measured using a fluorometer after ethanol extraction of the GF/F-filters.

Description: During the cruise POS470 on board the German R/V Poseidon, we collected water with a CTD SBE911plus equipped with 14 Hydrobios free flow bottles of 5 L each in 31 stations (resulting in more than 300 samples) and during transect time in the Madeira basin region, Northeast Atlantic. We aimed to study the physical and biogeochemical conditions in the upper 2000 m of the water column around the catchment area of Kiel 276 in May/June 2014. We measured concentrations of chlorophyll a, phaeopigments, suspended particulate material (SPM), and nutrients such as nitrate, nitrite, phosphate and silicate. Also, we determined concentrations of particulate organic carbon (POC) and particulate organic nitrogen (PON) as well as dissolved organic carbon (DOC) and dissolved nitrogen (DN). The physical oceanography during the survey is available at PANGAEA (https://doi.org/10.1594/PANGAEA.949132). Brief description of the methodology used: - Nitrate, nitrite, phosphate and silicate were measured by continuous flow analysis. - Oxygen was measured on one sample at each station by potentiometric Winkler titration. - DOC and DN were measured by catalytic oxidation after filtered with GF/F-filters. - POC and PON were measured by means of an elemental analyser after filtered with pre-combusted GF/F-filters. - Suspended particulate material (SPM) was determined gravimetrically after pre-combusted and weighted GF/F-filters filtration. - Chlorophyll a and phaeopigments were measured using a fluorometer after ethanol extraction of the GF/F-filters.

Description: During the cruise POS470 on board the German R/V Poseidon, we measured temperature, salinity, dissolved oxygen, fluorescence and turbidity on 33 stations in the Madeira Basin, Northeast Atlantic in May and June 2014. We aimed to study the physical and biogeochemical conditions in the upper 2000 m of the water column in the catchment area of Kiel 276. The CTD stations are distributed along three meridians (23°W, 22°W, and 21°W) and between 30° and 37°N to locate the Azores Front. The dissolved oxygen data is noisy below 1700 m. Since there was no measurement of dissolved oxygen (Winkler titration) during the cruise, the data cannot be calibrated.