GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Characteristics of the surface water DMS and p CO2 distributions and their relationships in the Southern Ocean, southeast Indian Ocean, and northwest Pacific Ocean (2017)
    AGU (American Geophysical Union) | Wiley
    In:  Global Biogeochemical Cycles, 31 (8). pp. 1318-1331.
    Details
    Publication Date: 2020-02-06
    Description: Oceanic dimethyl sulfide (DMS) is of interest due to its critical influence on atmospheric sulfur compounds in the marine atmosphere and its hypothesized significant role in global climate. High-resolution shipboard underway measurements of surface seawater DMS and the partial pressure of carbon dioxide (pCO2) were conducted in the Atlantic Ocean and Indian Ocean sectors of the Southern Ocean (SO), the southeast Indian Ocean, and the northwest Pacific Ocean from February to April 2014 during the 30th Chinese Antarctic Research Expedition. The SO, particularly in the region south of 58°S, had the highest mean surface seawater DMS concentration of 4.1 ± 8.3 nM (ranged from 0.1 to 73.2 nM) and lowest mean seawater pCO2 level of 337 ± 50 μatm (ranged from 221 to 411 μatm) over the entire cruise. Significant variations of surface seawater DMS and pCO2 in the seasonal ice zone (SIZ) of SO were observed, which are mainly controlled by biological process and sea ice activity. We found a significant negative relationship between DMS and pCO2 in the SO SIZ using 0.1° resolution, [DMS] seawater = -0.160 [pCO2] seawater + 61.3 (r2 = 0.594, n = 924, p 〈 0.001). We anticipate that the relationship may possibly be utilized to reconstruct the surface seawater DMS climatology in the SO SIZ. Further studies are necessary to improve the universality of this approach. Key Points: • The characteristics of surface water DMS and pCO2 distributions from the Southern Ocean to northwest Pacific Ocean are investigated • The correlations between DMS, pCO2, and environmental parameters are analyzed • Anticorrelation between DMS and pCO2 is found in the seasonal ice zone of the Southern Ocean
    Type: Article , PeerReviewed
    Format: text
    Format: text
    Format: other
    Format: other
    DOI: 10.1002/2017GB005637
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 2
    facet.materialart.
    Unknown
    The influence of air-sea fluxes on atmospheric aerosols during the summer monsoon over the tropical Indian Ocean (2018)
    AGU (American Geophysical Union) | Wiley
    In:  Geophysical Research Letters, 45 (1). pp. 418-426.
    Details
    Publication Date: 2021-03-19
    Description: During the summer monsoon, the western tropical Indian Ocean is predicted to be a hot spot for dimethylsulfide emissions, the major marine sulfur source to the atmosphere, and an important aerosol precursor. Other aerosol relevant fluxes, such as isoprene and sea spray, should also be enhanced, due to the steady strong winds during the monsoon. Marine air masses dominate the area during the summer monsoon, excluding the influence of continentally derived pollutants. During the SO234-2/235 cruise in the western tropical Indian Ocean from July to August 2014, directly measured eddy covariance DMS fluxes confirm that the area is a large source of sulfur to the atmosphere (cruise average 9.1 μmol m−2 d−1). The directly measured fluxes, as well as computed isoprene and sea spray fluxes, were combined with FLEXPART backward and forward trajectories to track the emissions in space and time. The fluxes show a significant positive correlation with aerosol data from the Terra and Suomi-NPP satellites, indicating a local influence of marine emissions on atmospheric aerosol numbers.
    Type: Article , PeerReviewed , info:eu-repo/semantics/article
    Format: text
    DOI: 10.1002/2017GL076410
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 3
    facet.materialart.
    Unknown
    Transport Variability of Very Short Lived Substances From the West Indian Ocean to the Stratosphere (2018)
    AGU (American Geophysical Union) | Wiley
    In:  Journal of Geophysical Research: Atmospheres, 123 (10). pp. 5720-5738.
    Details
    Publication Date: 2021-02-08
    Description: Halogen- and sulfur-containing compounds are supersaturated in the surface ocean, which results in their emission to the atmosphere. These compounds can be transported to the stratosphere, where they impact ozone, the background aerosol layer, and climate. In this study we calculate the seasonal and interannual variability of transport from the West Indian Ocean (WIO) surface to the stratosphere for 2000-2016 with the Lagrangian transport model FLEXPART using ERA-Interim meteorological fields. We investigate the transport relevant for very short lived substances (VSLS) with tropospheric lifetimes corresponding to dimethylsulfide (1 day), methyl iodide (CH3I, 3.5 days), bromoform (CHBr3, 17 days), and dibromomethane (CH2Br2, 150 days). The stratospheric source gas injection of VSLS tracers from the WIO shows a distinct annual cycle associated with the Asian monsoon. Over the 16-year time series, a slight increase in source gas injection from the WIO to the stratosphere is found for all VSLS tracers and during all seasons. The interannual variability shows a relationship with sea surface temperatures in the WIO as well as the El Niño-Southern Oscillation. During boreal spring of El Niño, enhanced stratospheric injection of VSLS from the tropical WIO is caused by positive sea surface temperature anomalies and enhanced vertical uplift above the WIO. During boreal fall of La Niña, strong injection is related to enhanced atmospheric upward motion over the East Indian Ocean and a prolonged Indian summer monsoon season. Related physical mechanisms and uncertainties are discussed in this study
    Type: Article , PeerReviewed
    Format: text
    Format: text
    DOI: 10.1029/2017JD027563
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 4
    facet.materialart.
    Unknown
    Seasonal variability of methyl iodide in the Kiel Fjord (2014)
    AGU (American Geophysical Union) | Wiley
    In:  Journal of Geophysical Research: Oceans, 119 (3). pp. 1609-1620.
    Details
    Publication Date: 2019-09-23
    Description: From October 2008 to November 2010, CH3I concentrations were measured in the Kiel Fjord together with potentially related biogeochemical and physical parameters. A repeating seasonal cycle of CH3I was observed with highest concentrations in summer (ca. 8.3 pmol L−1; June and July) and lowest concentrations in winter (ca. 1.5 pmol L−1; December to February). A strong positive correlation at zero lag between [CH3I] and solar radiation (R2 = 0.93) was observed, whereas correlations with other variables (SST, Chlorophyll a) were weaker, and they lagged CH3I by ca. 1 month. These results appear consistent with the hypothesis that SSR is the primary forcing of CH3I production in surface seawater, possibly through a photochemical pathway. A mass balance of the monthly averaged data was used to infer mean rates of daily net production (Pnet) and losses for CH3I over the year. The sea-to-air flux of CH3I in the Kiel Fjord averaged 3.1 nmol m−2 d−1, the mean chemical loss rate was 0.047 pmol L−1 d−1, and Pnet varied systematically from winter to summer (from 0 to 0.6 pmol L−1 d−1). Pnet was correlated at zero lag with SST, SSR, and Chla (R2 = 0.55, 0.67, and 0.73, respectively, p 〈〈 0.01). The lagged cross-correlation analysis indicated that SSR led Pnet by 1 month, whereas the strongest cross correlations with Chla were at lags of 0 to +1 month, and SST lagged Pnet by 1 month. The broad seasonal peak of Pnet makes it difficult to determine the key factor controlling CH3I net production using in situ concentration data alone.
    Type: Article , PeerReviewed
    Format: text
    DOI: 10.1002/2013JC009328
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 5
    facet.materialart.
    Unknown
    A time series of incubation experiments to examine the production and loss of CH3I in surface seawater (2014)
    AGU (American Geophysical Union) | Wiley
    In:  Journal of Geophysical Research: Oceans, 119 (12). pp. 8242-8254.
    Details
    Publication Date: 2019-04-04
    Description: In order to investigate production pathways of methyl iodide and controls on emissions from the surface ocean, a set of repeated in vitro incubation experiments were performed over an annual cycle in the context of a time series of in situ measurements in Kiel Fjord (54.3°N, 10.1°E). The incubation experiments revealed a diurnal variation of methyl iodide in samples exposed to natural light, with maxima during day time and losses during night hours. The amplitude of the daily accumulation varied seasonally and was not affected by filtration (0.2 µm), consistent with a photochemical pathway for CH3I production. The methyl iodide loss rate at nighttime correlates with the concentration accumulated during daytime suggesting a first-order loss mechanism (R2 = 0.29, p 〈〈 0.01). Daily (24 h) net production (Pnet) was similar in magnitude between in vitro and in situ mass balances. However, the estimated gross production (Pgross) of methyl iodide ranged from −0.07 to 2.24 pmol L−1 d−1 and was up to 5 times higher in summer than Pnet calculated from the in situ study. The large excess of Pgross over Pnet in summer revealed by the incubation experiments is a consequence of large losses of CH3I by as-yet uncharacterized processes (e.g., biological degradation or chemical pathways other than Cl− substitution).
    Type: Article , PeerReviewed
    Format: text
    DOI: 10.1002/2014JC010223
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 6
    facet.materialart.
    Unknown
    Nutrient availability determines dimethyl sulfide and isoprene distribution in the eastern Atlantic Ocean (2014)
    AGU (American Geophysical Union) | Wiley
    In:  Geophysical Research Letters, 41 (9). pp. 3181-3188.
    Details
    Publication Date: 2019-09-24
    Description: Continuous high-resolution underway measurements of dimethyl sulfide (DMS) and isoprene in the ocean surface were conducted from Germany to South Africa in November 2008. DMS, total dimethylsulfoniopropionate (DMSPt), isoprene and 19'-hexanoyloxyfucoxanthin (19'-hex) correlated in nitrogen-depleted regions when they were clustered by nitrogen to phosphorous ratio (N:P). The 19'-hex-containing algae groups might be a common source of DMS, DMSPt, and isoprene in the low N: P regions. Additionally, DMS and isoprene correlated in nitrate-depleted regions when they were clustered against nitrate concentrations. Correlations between DMS and isoprene were also found within nitrate-depleted eddies encountered along the cruise track. Eddies with N: P of similar to 2.8 showed the highest positive correlations between DMS and isoprene. We conclude that the DMS/isoprene relationships in the eastern Atlantic Ocean were influenced by nutrient availability, with implications for using nutrients to predict the DMS and isoprene concentrations over a range of oceanographic areas depleted in nitrogen
    Type: Article , PeerReviewed
    Format: text
    DOI: 10.1002/2014GL059547
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 7
    facet.materialart.
    Unknown
    Ship-based measurement of air-sea CO2exchange by eddy covariance (2010)
    AGU (American Geophysical Union)
    In:  Journal of Geophysical Research: Atmospheres, 115 (D2). D02304.
    Details
    Publication Date: 2018-02-06
    Description: A system for the shipboard measurement of air-sea CO2 fluxes by eddy covariance was developed and tested. The system was designed to reduce two major sources of experimental uncertainty previously reported. First, the correction for in situ water vapor fluctuations (the “Webb” correction) was reduced by 97% by drying the air sample stream. Second, motion sensitivity of the gas analyzer was reduced by using an open-path type sensor that was converted to a closed-path configuration to facilitate drying of the air stream. High-quality CO2 fluxes were obtained during 429 14 min flux intervals during two cruises in the North Atlantic. The results suggest that the gas analyzer resolved atmospheric CO2 fluctuations well below its RMS noise level. This noise was uncorrelated with the vertical wind and therefore filtered out by the flux calculation. Using climatological data, we estimate that the techniques reported here could enable high-quality measurements of air-sea CO2 flux over much of the world oceans.
    Type: Article , PeerReviewed
    Format: text
    DOI: 10.1029/2009JD012193
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 8
    facet.materialart.
    Unknown
    Eddy correlation measurements of the air/sea flux of dimethylsulfide over the North Pacific Ocean (2007)
    AGU (American Geophysical Union)
    In:  Journal of Geophysical Research: Atmospheres, 112 (D3). D03301.
    Details
    Publication Date: 2018-01-15
    Description: Shipboard measurements of air/sea fluxes and sea surface concentrations of dimethylsulfide (DMS) were made over the tropical and midlatitude North Pacific Ocean. Atmospheric pressure chemical ionization mass spectrometry was used to measure DMS levels in ambient air and in air equilibrated with surface seawater drawn from a depth of 5 m. Air/sea fluxes were obtained using eddy covariance. Corrections and uncertainties involved in the calculation of fluxes from shipboard data are discussed. The surface ocean DMS concentrations measured during this study ranged from 1 to 10 nM, and atmospheric mixing ratios ranged from 20 to 1000 ppt. Air/sea fluxes ranged from 0.47 to 39 mu mol m(-2) d(-1). Most of the variance in the fluxes can be accounted for by variations in sea surface concentration (37%) and wind speed (19%). Gas transfer coefficients derived from the measurements are generally consistent with those derived from deliberate inert gas tracer experiments and eddy covariance measurements of CO(2). The gas transfer coefficients exhibit wind speed dependence, but the variance in the data is sufficiently large that they do not constrain the functionality of the wind speed dependence of gas exchange.
    Type: Article , PeerReviewed
    Format: text
    DOI: 10.1029/2006JD007293
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 9
    facet.materialart.
    Unknown
    Oceanic uptake and the global atmospheric acetone budget (2005)
    AGU (American Geophysical Union)
    In:  Geophysical Research Letters, 32 (15). L15806.
    Details
    Publication Date: 2018-03-28
    Description: In this study, direct measurements of the air/ sea flux of acetone were made over the North Pacific Ocean. The results demonstrate that the net flux of acetone is into, rather than out of the oceans. The extrapolated global ocean uptake of 48 Tg yr(-1) requires a major revision of the atmospheric acetone budget. This result is consistent with a recent reevaluation of acetone photodissociation quantum yields.
    Type: Article , PeerReviewed
    Format: text
    Format: text
    DOI: 10.1029/2005GL023285
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 10
    facet.materialart.
    Unknown
    Space-based retrievals of air-sea gas transfer velocities using altimeters: Calibration for dimethyl sulfide (2012)
    AGU (American Geophysical Union)
    In:  Journal of Geophysical Research: Oceans, 117 (C8). C08028.
    Details
    Publication Date: 2019-09-24
    Description: This study is the first to directly correlate gas transfer velocity, measured at sea using the eddy-correlation (EC) technique, and satellite altimeter backscattering. During eight research cruises in different parts of the world, gas transfer velocity of dimethyl sulfide (DMS) was measured. The sample times and locations were compared with overpass times and locations of remote sensing satellites carrying Ku-band altimeters: ERS-1, ERS-2, TOPEX, POSEIDON, GEOSAT Follow-On, JASON-1, JASON-2 and ENVISAT. The result was 179 pairs of gas transfer velocity measurements and backscattering coefficients. An inter-calibration of the different altimeters significantly reduced data scatter. The inter-calibrated data was best fitted to a quadratic relation between the inverse of the backscattering coefficients and the gas transfer velocity measurements. A gas transfer parameterization based on backscattering, corresponding with sea surface roughness, might be expected to perform better than wind speed-based parameterizations. Our results, however, did not show improvement compared to direct correlation of shipboard wind speeds. The relationship of gas transfer velocity to satellite-derived backscatter, or wind speed, is useful to provide retrieval algorithms. Gas transfer velocity (cm/hr), corrected to a Schmidt number of 660, is proportional to wind speed (m/s). The measured gas transfer velocity is controlled by both the individual water-side and air-side gas transfer velocities. We calculated the latter using a numerical scheme, to derive water-side gas transfer velocity. DMS is sufficiently soluble to neglect bubble-mediated gas transfer, thus, the DMS transfer velocities could be applied to estimate water-side gas transfer velocities through the unbroken surface of any other gas Key Points: - Show relations between altimeter data and field values of air-sea gas transfer - DMS gas transfer velocity can be used to estimate direct gas transfer of any gas - Direct gas transfer velocity (for Sc = 660) is roughly double 10 m wind speed
    Type: Article , PeerReviewed
    Format: text
    DOI: 10.1029/2011JC007535
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...