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Direct measurements of CO2 flux in the Greenland Sea
During summer 2006 eddy correlation CO2 fluxes were measured in the Greenland Sea using a novel system set-up with two shrouded LICOR-7500 detectors. One detector was used exclusively to determine, and allow the removal of, the bias on CO2 fluxes due to sensor motion. A recently published correction method for the CO2-H2O cross-correlation was applied to the data set. We show that even with shrouded sensors the data require significant correction due to this cross-correlation. This correction adjusts the average CO2 flux by an order of magnitude from -6.7 x 10â»ÂČ mol mâ»ÂČ dayâ»Âč to -0.61 x 10â»ÂČ mol mâ»ÂČ dayâ»Âč, making the corrected fluxes comparable to those calculated using established parameterizations for transfer velocity
Stratus Ocean Reference Station (20ËS, 85ËW), mooring recovery and deployment cruise R/V Ronald H. Brown cruise 05-05, September 26, 2005âOctober 21, 2005
The Ocean Reference Station at 20°S, 85°W under the stratus clouds west of northern Chile is being maintained to provide
ongoing, climate-quality records of surface meteorology, of air-sea fluxes of heat, freshwater, and momentum, and of upper ocean
temperature, salinity, and velocity variability. The Stratus Ocean Reference Station (ORS Stratus) is supported by the National
Oceanic and Atmospheric Administrationâs (NOAA) Climate Observation Program. It is recovered and redeployed annually, with
cruises that have come between October and December. During the October 2005 cruise of NOAAâs R/V Ronald H. Brown to the
ORS Stratus site, the primary activities were recovery of the WHOI surface mooring that had been deployed in December 2004,
deployment of a new WHOI surface mooring at that site, in-situ calibration of the buoy meteorological sensors by comparison
with instrumentation put on board by staff of the NOAA Environmental Technology Laboratory (ETL), and observations of the
stratus clouds and lower atmosphere by NOAA ETL. The ORS Stratus buoys are equipped with two Improved Meteorological
(IMET) systems, which provide surface wind speed and direction, air temperature, relative humidity, barometric pressure,
incoming shortwave radiation, incoming longwave radiation, precipitation rate, and sea surface temperature. The IMET data are
made available in near real time using satellite telemetry. The mooring line carries instruments to measure ocean salinity,
temperature, and currents. The ETL instrumentation used during the 2005 cruise included cloud radar, radiosonde ballons, and
sensors for mean and turbulent surface meteorology. In addition, two technicians from the University of Concepcion collected
water samples for chemical analysis. Finally, the cruise hosted a teacher participating in NOAAâs Teacher at Sea Program.Funding was provided by the National Oceanic and Atmospheric Administration
under Grant No. NA17RJ1223 and the Cooperative Institute for Climate and Ocean Research (CICOR)
WHOI Hawaii Ocean Timeseries Station (WHOTS) : WHOTS-9 2012 mooring turnaround cruise report
The Woods Hole Oceanographic Institution (WHOI) Hawaii Ocean Timeseries Site (WHOTS), 100 km north of Oahu,
Hawaii, is intended to provide long-term, high-quality air-sea fluxes as a part of the NOAA Climate Observation
Program. The WHOTS mooring also serves as a coordinated part of the Hawaii Ocean Timeseries (HOT) program,
contributing to the goals of observing heat, fresh water and chemical fluxes at a site representative of the oligotrophic
North Pacific Ocean. The approach is to maintain a surface mooring outfitted for meteorological and oceanographic
measurements at a site near 22.75°N, 158°W by successive mooring turnarounds. These observations will be used to
investigate airâsea interaction processes related to climate variability. This report documents recovery of the eighth
WHOTS mooring (WHOTS-8) and deployment of the ninth mooring (WHOTS-9). Both moorings used Surlyn foam
buoys as the surface element and were outfitted with two AirâSea Interaction Meteorology (ASIMET) systems. Each
ASIMET system measures, records, and transmits via Argos satellite the surface meteorological variables necessary to
compute airâsea fluxes of heat, moisture and momentum. The upper 155 m of the moorings were outfitted with
oceanographic sensors for the measurement of temperature, conductivity and velocity in a cooperative effort with R.
Lukas of the University of Hawaii. A pCO2 system was installed on the buoys in cooperation with Chris Sabine at the
Pacific Marine Environmental Laboratory. A set of radiometers were installed in cooperation with Sam Laney at
WHOI. The WHOTS mooring turnaround was done on the NOAA ship Hiâialakai by the Upper Ocean Processes
Group of the Woods Hole Oceanographic Institution. The cruise took place between 12 and 19 June 2012. Operations
began with deployment of the WHOTS-9 mooring on 13 June. This was followed by meteorological intercomparisons
and CTDs. Recovery of the WHOTS-8 mooring took place on 16 June. This report describes these cruise operations,
as well as some of the in-port operations and pre-cruise buoy preparations.Funding was provided by the National Oceanic and Atmospheric Administration
under Grant No. NA09OAR4320129 and the Cooperative Institute for the
North Atlantic Region (CINAR)
Direct covariance measurement of CO2 gas transfer velocity during the 2008 Southern Ocean Gas Exchange Experiment: Wind speed dependency
Direct measurements of air-sea heat, momentum, and mass (including CO2, DMS, and water vapor) fluxes using the direct covariance method were made over the open ocean from the NOAA R/V Ronald H. Brown during the Southern Ocean Gas Exchange (SO GasEx) program. Observations of fluxes and the physical processes associated with driving air-sea exchange are key components of SO GasEx. This paper focuses on the exchange of CO2 and the wind speed dependency of the transfer velocity, k, used to model the CO2 flux between the atmosphere and ocean. A quadratic dependence of k on wind speed based on dual tracer experiments is most frequently encountered in the literature. However, in recent years, bubble-mediated enhancement of k, which exhibits a cubic relationship with wind speed, has emerged as a key issue for flux parameterization in high-wind regions. Therefore, a major question addressed in SO GasEx is whether the transfer velocities obey a quadratic or cubic relationship with wind speed. After significant correction to the flux estimates (primarily due to moisture contamination), the direct covariance CO2 fluxes confirm a significant enhancement of the transfer velocity at high winds compared with previous quadratic formulations. Regression analysis suggests that a cubic relationship provides a more accurate parameterization over a wind speed range of 0 to 18 m sâ1. The Southern Ocean results are in good agreement with the 1998 GasEx experiment in the North Atlantic and a recent separate field program in the North Sea
Measurements from the RV Ronald H. Brown and related platforms as part of the Atlantic Tradewind Ocean-Atmosphere Mesoscale Interaction Campaign (ATOMIC)
© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Quinn, P. K., Thompson, E. J., Coffman, D. J., Baidar, S., Bariteau, L., Bates, T. S., Bigorre, S., Brewer, A., de Boer, G., de Szoeke, S. P., Drushka, K., Foltz, G. R., Intrieri, J., Iyer, S., Fairall, C. W., Gaston, C. J., Jansen, F., Johnson, J. E., Krueger, O. O., Marchbanks, R. D., Moran, K. P., Noone, D., Pezoa, S., Pincus, R., Plueddemann, A. J., Poehlker, M. L., Poeschl, U., Melendez, E. Q., Royer, H. M., Szczodrak, M., Thomson, J., Upchurch, L. M., Zhang, C., Zhang, D., & Zuidema, P. Measurements from the RV Ronald H. Brown and related platforms as part of the Atlantic Tradewind Ocean-Atmosphere Mesoscale Interaction Campaign (ATOMIC). Earth System Science Data, 13(4), (2021): 1759-1790, https://doi.org/10.5194/essd-13-1759-2021.The Atlantic Tradewind Ocean-Atmosphere Mesoscale Interaction Campaign (ATOMIC) took place from 7 January to 11 July 2020 in the tropical North Atlantic between the eastern edge of Barbados and 51ââW, the longitude of the Northwest Tropical Atlantic Station (NTAS) mooring. Measurements were made to gather information on shallow atmospheric convection, the effects of aerosols and clouds on the ocean surface energy budget, and mesoscale oceanic processes. Multiple platforms were deployed during ATOMIC including the NOAA RV Ronald H. Brown (RHB) (7 January to 13 February) and WP-3D Orion (P-3) aircraft (17 January to 10 February), the University of Colorado's Robust Autonomous Aerial Vehicle-Endurant Nimble (RAAVEN) uncrewed aerial system (UAS) (24 January to 15 February), NOAA- and NASA-sponsored Saildrones (12 January to 11 July), and Surface Velocity Program Salinity (SVPS) surface ocean drifters (23 January to 29 April). The RV Ronald H. Brown conducted in situ and remote sensing measurements of oceanic and atmospheric properties with an emphasis on mesoscale oceanicâatmospheric coupling and aerosolâcloud interactions. In addition, the ship served as a launching pad for Wave Gliders, Surface Wave Instrument Floats with Tracking (SWIFTs), and radiosondes. Details of measurements made from the RV Ronald H. Brown, ship-deployed assets, and other platforms closely coordinated with the ship during ATOMIC are provided here. These platforms include Saildrone 1064 and the RAAVEN UAS as well as the Barbados Cloud Observatory (BCO) and Barbados Atmospheric Chemistry Observatory (BACO). Inter-platform comparisons are presented to assess consistency in the data sets. Data sets from the RV Ronald H. Brown and deployed assets have been quality controlled and are publicly available at NOAA's National Centers for Environmental Information (NCEI) data archive (https://www.ncei.noaa.gov/archive/accession/ATOMIC-2020, last access: 2 April 2021). Point-of-contact information and links to individual data sets with digital object identifiers (DOIs) are provided herein.NOAA's Climate Variability and Predictability Program provided funding under NOAA CVP NA19OAR4310379, GC19-301, and GC19-305. The Joint Institute for the Study of the Atmosphere and Ocean (JISAO) supported this study under NOAA cooperative agreement NA15OAR4320063. Additional support was provided by the NOAA's Uncrewed Aircraft Systems (UAS) Program Office, NOAA's Physical Sciences Laboratory, and NOAA AOML's Physical Oceanography Division. The NTAS project is funded by the NOAA's Global Ocean Monitoring and Observing Program (CPO FundRef number 100007298), through the Cooperative Institute for the North Atlantic Region (CINAR) under cooperative agreement NA14OAR4320158
Short-Lived Trace Gases in the Surface Ocean and the Atmosphere
The two-way exchange of trace gases between the ocean and the atmosphere is important for both the chemistry and physics of the atmosphere and the biogeochemistry of the oceans, including the global cycling of elements. Here we review these exchanges and their importance for a range of gases whose lifetimes are generally short compared to the main greenhouse gases and which are, in most cases, more reactive than them. Gases considered include sulphur and related compounds, organohalogens, non-methane hydrocarbons, ozone, ammonia and related compounds, hydrogen and carbon monoxide. Finally, we stress the interactivity of the system, the importance of process understanding for modeling, the need for more extensive field measurements and their better seasonal coverage, the importance of inter-calibration exercises and finally the need to show the importance of air-sea exchanges for global cycling and how the field fits into the broader context of Earth System Science
Overview of the MOSAiC expeditionâAtmosphere
With the Arctic rapidly changing, the needs to observe, understand, and model the changes are essential. To support these needs, an annual cycle of observations of atmospheric properties, processes, and interactions were made while drifting with the sea ice across the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. An international team designed and implemented the comprehensive program to document and characterize all aspects of the Arctic atmospheric system in unprecedented detail, using a variety of approaches, and across multiple scales. These measurements were coordinated with other observational teams to explore cross-cutting and coupled interactions with the Arctic Ocean, sea ice, and ecosystem through a variety of physical and biogeochemical processes. This overview outlines the breadth and complexity of the atmospheric research program, which was organized into 4 subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets. Atmospheric variability over the annual cycle revealed important influences from a persistent large-scale winter circulation pattern, leading to some storms with pressure and winds that were outside the interquartile range of past conditions suggested by long-term reanalysis. Similarly, the MOSAiC location was warmer and wetter in summer than the reanalysis climatology, in part due to its close proximity to the sea ice edge. The comprehensiveness of the observational program for characterizing and analyzing atmospheric phenomena is demonstrated via a winter case study examining air mass transitions and a summer case study examining vertical atmospheric evolution. Overall, the MOSAiC atmospheric program successfully met its objectives and was the most comprehensive atmospheric measurement program to date conducted over the Arctic sea ice. The obtained data will support a broad range of coupled-system scientific research and provide an important foundation for advancing multiscale modeling capabilities in the Arctic
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