ALBERT

Description: Flow-through pCO2, Temp/Sal, and O2 measurements across the Atlantic (Meteor M133 cruise 2016/17) from Cape Town, SA to Stanley, The Falkland Islands. Surface water flow-through system set up on R.V. Meteor M133 (15.12.2016 - 13.01.2017), across the Atlantic. All sensors ran on the same water in a complete flow-through sensor set-up. Depth of pumps: 5.7m from the moon pool Flow rate: ~ 5-6 L/min All data was processed following Canning et al., 2020 (In Review). Sensor data in separate files. Sensors: pCO2: CONTROS HydroC CO2 FT - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany; now -4H-JENA engineering GmbH, Jena, Germany O2: CONTROS HydroFlash O2 - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany SBE 45 Micro Thermosalinograph - Sea-Bird Electronics, Bellevue, USA D-SHIP data from the ships SBE 38 and 21 for sea surface temperature and salinity. Latitude and longitude also from the D-SHIP. All sensors combined together in the same flow-through set-up.

Description: Flow-through pCO2, Temp/Sal, and O2 measurements across the Atlantic (Meteor M133 cruise 2016/17) from Cape Town, SA to Stanley, The Falkland Islands. Surface water flow-through system set up on R.V. Meteor M133 (15.12.2016 - 13.01.2017), across the Atlantic. All sensors ran on the same water in a complete flow-through sensor set-up. Depth of pumps: 5.7m from the moon pool Flow rate: ~ 5-6 L/min All data was processed following Canning et al., 2020 (In Review). Sensor data in separate files. Sensors: pCO2: CONTROS HydroC CO2 FT - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany; now -4H-JENA engineering GmbH, Jena, Germany O2: CONTROS HydroFlash O2 - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany SBE 45 Micro Thermosalinograph - Sea-Bird Electronics, Bellevue, USA D-SHIP data from the ships SBE 38 and 21 for sea surface temperature and salinity. Latitude and longitude also from the D-SHIP. All sensors combined together in the same flow-through set-up.

Description: Flow-through pCO2, Temp/Sal, and O2 measurements across the Atlantic (Meteor M133 cruise 2016/17) from Cape Town, SA to Stanley, The Falkland Islands. Surface water flow-through system set up on R.V. Meteor M133 (15.12.2016 - 13.01.2017), across the Atlantic. All sensors ran on the same water in a complete flow-through sensor set-up. Depth of pumps: 5.7m from the moon pool Flow rate: ~ 5-6 L/min All data was processed following Canning et al., 2020 (In Review). Sensor data in separate files. Sensors: pCO2: CONTROS HydroC CO2 FT - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany; now -4H-JENA engineering GmbH, Jena, Germany O2: CONTROS HydroFlash O2 - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany SBE 45 Micro Thermosalinograph - Sea-Bird Electronics, Bellevue, USA D-SHIP data from the ships SBE 38 and 21 for sea surface temperature and salinity. Latitude and longitude also from the D-SHIP. All sensors combined together in the same flow-through set-up.

Description: Flow-through pCO2, pCH4 Temp/Sal, and O2 measurements in the western Baltic Sea during SCOR cruise (separate to the intercalibration exercise). Surface water flow-through sensor system set up on R.V. Elisabeth Mann Borgese (15.10.2016 - 22.10.2016). All sensors ran on the same water in a complete flow-through sensor set-up at a resolution of 1 minute. Depth of pumps: 3m Flow rate: ~ 5-6 L/min All data was processed following Canning et al., 2020 (In Review). Sensor data in separate files. Sensors: pCO2: CONTROS HydroC CO2 FT - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany; now -4H-JENA engineering GmbH, Jena, Germany O2: CONTROS HydroFlash O2 - formerly Kongsberg Maritime Contros GmbH, Kiel, Germany SBE 45 Micro Thermosalinograph - Sea-Bird Electronics, Bellevue, USA Temperature, salinity, latitude and longitude included are also from the D-SHIP. Only half the cruise dataset for pCH4 due to internal issue with the sensor (see Canning et al., 2020).

Description: The ocean and inland waters are two separate regimes, with concentrations in greenhouse gases differing on orders of magnitude between them. Together, they create the land–ocean aquatic continuum (LOAC), which comprises itself largely of areas with little to no data with regards to understanding the global carbon system. Reasons for this include remote and inaccessible sample locations, often tedious methods that require collection of water samples and subsequent analysis in the lab, and the complex interplay of biological, physical and chemical processes. This has led to large inconsistencies, increasing errors and has inevitably lead to potentially false upscaling. A set-up of multiple pre-existing oceanographic sensors allowing for highly detailed and accurate measurements was successfully deployed in oceanic to remote inland regions over extreme concentration ranges. The set-up consists of four sensors simultaneously measuring pCO2, pCH4 (both flow-through, membrane-based non-dispersive infrared (NDIR) or tunable diode laser absorption spectroscopy (TDLAS) sensors), O2 and a thermosalinograph at high resolution from the same water source. The flexibility of the system allowed for deployment from freshwater to open ocean conditions on varying vessel sizes, where we managed to capture day–night cycles, repeat transects and also delineate small-scale variability. Our work demonstrates the need for increased spatiotemporal monitoring and shows a way of homogenizing methods and data streams in the ocean and limnic realms.

Description: Ocean warming severely impacts oxygen distribution, because it reduces oxygen solubility and increases stratification in the upper ocean. Quantifying changes of oxygen levels will improve the understanding of chemical, biological and physical processes, especially in Oxygen Minimum Zones characterized by intensification and spatial expansion. Despite existing optical sensors (optodes) that accurately measure ocean oxygen levels, users wish for an improved spatial and temporal measurement resolution from profiling platforms. We demonstrate the utility of a novel, commercially-available optode that shows a temperature-dependent response time (t63%) of about 4 seconds, which is significantly faster compared to other optical oxygen sensors. This optode can be used on a wide range of observation platforms such as ships, time-series stations, unmanned surface vehicles and autonomous underwater platforms such as floats and gliders. We aim to characterize this optode regarding oxygen, temperature, salinity and pressure dependence, long-term stability and drift, response time and air-calibration compatibility. Results build on data from laboratory experiments and field deployments in the Tropical and Southern Atlantic. Underway, mooring, float and CTD-cast applications promise high quality observations including fast oxygen level changes on small scales. We will conclude with a status update on our general optode technology developments.

Description: Innovation and improvement report on the extension of capabilities to measure emerging EOVs including metagenomics across different observational platforms with links to MicroB3 best practice.

Description: Carbon dioxide (CO2) and methane (CH4) are major greenhouse gases (GHG) and have been under constant monitoring for decades. Both gases have significantly increased in recent years due to anthropogenic activities. This has huge detrimental repercussions within natural systems including the warming of the planet. Although these GHG are extremely significant, there are also vast areas of study with little to no data in regards to emissions and budgets. These gaps are mainly within the aquatic regions (or the Land Ocean Aquatic Continuum (LOAC)). As a consequence, there can be large discrepancies between budget numbers and in turn, scaling and future predictions. In order to combine oceanographic and limnological methods this thesis presents a novel sensor package and show its application in multiple campaigns across the entire LOAC. The sensor set-up contained the oceanographic sensors HydroC CO2 FT (pCO2), HydroC CH4 FT (CH4), HydroFlash O2 (O2) and a thermosalinograph for temperature and conductivity measuring continuously, all simultaneously. We extensively mapped ocean to inland regions. The results first describe the processes to enable the set-up to be used across the LOAC boundary over 3 seasons. Extensive corrections were needed for the data to be fully appreciated for all salinities specifically in fresh inland waters. The data was then split between CO2 and CH4, where, in inland waters, further analyses were performed. The area of interest was the Danube Delta, which was found to be continuously supersaturated in regards to CH4 and fluctuating between a source and sink for CO2. Extraction of TA was possible, using the sensors continuous data by applying a simple model. In this extraction and the continuous data, large spatial-variability was observed and further analysed allowed for diel cycle extractions, which are usually disregarded in budgets and measurements. In channels, CH4 concentrations and fluxes were found to potentially be underestimated by up to +25% and +20% respectively when not including a full diel cycle. In lakes however, we found the opposite, with an overestimation in concentration and fluxes (+3.3% and +4.2%) when not considering the diel cycle, although this greatly depends on time of the sampling.

Description: Global estimates see river deltas and estuaries contributing about equally to CO2 and CH4 emissions as lakes and reservoirs, despite a factor 6 smaller surface area. Assessing the horizontal gradients in dissolved gas concentrations from large river reaches to connecting canals and wetland lakes remains a challenge in many deltaic systems. To elucidate the processes affecting local CO2 and CH4 concentrations in the Romanian part of the Danube Delta, we mapped dissolved O2, N2, He and Ar using a portable gas-equilibration membrane-inlet mass spectrometer (GE-MIMS), along with CO2, CH4, water temperature and conductivity. We measured the concentrations along the aquatic continuum from a small houseboat during two campaigns, in spring and autumn, to capture different hydrological and plant growth conditions. Delta-scale concentration patterns were comparably stable across seasons. Small connecting channels were highly influenced by the riparian wetland, which was strongest in the eastern part of the biosphere reserve. These sites represented the delta’s CO2 and CH4 hotspots and showed clear signs of excess air, i.e., supersaturation of dissolved noble gases with respect to air-saturated water. As the adjacent wetland was permanently inundated, this signal was likely caused by root aeration of Phragmites australis, as opposed to traditional excess air formation via water table fluctuations in the unsaturated zone. The special vegetation setting with reed growing on floating peat coincided with the highest CO2 and CH4 concentrations (〉700 μmol/L CO2 and 13 μmol/L CH4, respectively) observed in an adjacent channel. Shallow lakes, on the other hand, were major sites of photosynthetic production with O2 oversaturation reaching up to 150% in spring. The observed deficit in non-reactive gases (He, Ar and N2) indicated that the lakes were affected by O2 ebullition from macrophytes. According to our estimations, this ebullitive flux decreased O2 concentrations by up to 2 mg/L. This study highlights the effect of plant-mediated gas transfer on dissolved gas concentrations and supports recent studies stressing the need to account for ebullitive gas exchange when assessing metabolism parameters from O2 in shallow, productive settings.

Description: Large amounts of methane (CH4) could be released as a result of the gradual or abrupt thawing of Arctic permafrost due to global warming. Once available, this potent greenhouse gas is emitted into the atmosphere or transported laterally into aquatic ecosystems via hydrologic connectivity at the surface or via groundwaters. While high northern latitudes contribute up to 5 % of total global CH4 emissions, the specific contribution of Arctic rivers and streams is largely unknown. We analyzed high-resolution continuous CH4 concentrations measured between 15 and 17 June 2019 (late freshet) in a ∼120 km transect of the Kolyma River in northeast Siberia. The average partial pressure of CH4 (pCH4) in tributaries (66.8–206.8 µatm) was 2–7 times higher than in the main river channel (28.3 µatm). In the main channel, CH4 was up to 1600 % supersaturated with respect to atmospheric equilibrium. Key sites along the riverbank and at tributary confluences accounted for 10 % of the navigated transect and had the highest pCH4 (41 ± 7 µatm) and CH4 emissions (0.03 ± 0.004 ) compared to other sites in the main channel, contributing between 14 % to 17 % of the total CH4 flux in the transect. These key sites were characterized by warm waters (T〉14.5 ∘C) and low specific conductivities (κ〈88 µS cm−1). The distribution of CH4 in the river could be linked statistically to T and κ of the water and to their proximity to the shore z, and these parameters served as predictors of CH4 concentrations in unsampled river areas. The abundance of CH4-consuming bacteria and CH4-producing archaea in the river was similar to those previously detected in nearby soils and was also strongly correlated to T and κ. These findings imply that the source of riverine CH4 is closely related with sites near land. The average total CH4 flux density in the river section was 0.02 ± 0.006 , equivalent to an annual CH4 flux of 1.24×107 g CH4 yr−1 emitted during a 146 d open water season. Our study highlights the importance of high-resolution continuous CH4 measurements in Arctic rivers for identifying spatial and temporal variations, as well as providing a glimpse of the magnitude of riverine CH4 emissions in the Arctic and their potential relevance to regional CH4 budgets.