A global database of sea surface dimethylsulfide (DMS) measurements and a procedure to predict sea surface DMS as a function of latitude, longitude, and month

47 pages, 13 figures, 7 tablesA database of 15,617 point measurements of dimethylsulfide (DMS) in surface waters along with lesser amounts of data for aqueous and particulate dimethylsulfoniopropionate concentration, chlorophyll concentration, sea surface salinity and temperature, and wind speed has been assembled. The database was processed to create a series of climatological annual and monthly 1°x1°latitude-longitude squares of data. The results were compared to published fields of geophysical and biological parameters. No significant correlation was found between DMS and these parameters, and no simple algorithm could be found to create monthly fields of sea surface DMS concentration based on these parameters. Instead, an annual map of sea surface DMS was produced using an algorithm similar to that employed by Conkright et al. [1994]. In this approach, a first-guess field of DMS sea surface concentration measurements is created and then a correction to this field is generated based on actual measurements. Monthly sea surface grids of DMS were obtained using a similar scheme, but the sparsity of DMS measurements made the method difficult to implement. A scheme was used which projected actual data into months of the year where no data were otherwise presen

Removal of SO2 from the marine boundary layer over the Atlantic Ocean : a case study on the kinetics of the S(IV)oxidation on marine aerosols

Measurements of SO2 and NSS-SO42- were made over the Atlantic Ocean on board the RV Polarstern from October 9 to November 2, 1996, as part of the ALBATROSS campaign. The measurements were performed between 66.7 degrees N and 37.8 degrees S with a mean longitude of approximately 30 degrees W. The most frequent background values for SO2 were found to be 13 parts per trillion by volume (pptv) (0.54 mnol m(-3) at standard ambient temperature and pressure (SATP)) in the Southern Hemisphere, and 15 pptv (0.62 nmol m(-3) SATP) in the Northern Hemisphere. The mean values for total NSS-SO42- in particles with a d > 0.2 mu m were (5.99 +/- 2.93) nmol m(-3) (SATP) in the Southern Hemisphere, and (8.93 +/- 5.29) nmol m(-3) (SATP) in the Northern Hemisphere. An analysis of the size-fractionated aerosol samples (d > 1 mu m and 0.2 mu m 1 mu m. The main fraction of this NSS-SO42-. is most likely produced by the oxidation of dissolved SO2 via heterogeneous reactions occurring in the aqueous phase of coarse mode marine aerosols. A case study on the kinetics of this oxidation pathway was conducted during ALBATROSS. October 12, 1996, the ship sailed in the plume of a volcano on Iceland during its eruption from September 30 to October 13, 1996, as indicated by trajectory analysis and by the measurements of NSS-SO42- SO2, CO, and Hg, An empirical physicochemical approach considering the atmosphere as a natural flow reactor is used for the presented case study. The determined pseudo-first-order reaction rate constant for;the oxidation of SO, on marine aerosols is 3.31 x 10(-4) s(-1) at 25 degrees C. Assuming that the occurrence of coarse mode marine aerosols is the rate-limiting variable of the reaction, the second-order reaction rate constant is found to be 1.32 x 10(-6) cm(3) s(-1) particle(-1) at 25 degrees C. These values are in good agreement with results of previous field experiments as well as with the results of model studies

Untersuchung des atmosphaerischen Kreislaufes biogener Schwefelverbindungen und ihrer Reaktionen

SIGLETIB: RA 3092(68) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Bildung und Umwandlung biogener Schwefelverbindungen - Messungen von Dimethylsulfid und seinen Oxidationsprodukten (Schwerpunkt: Methansulfonsaeure) Abschlussbericht

With 99 refs., 15 tabs., 74 figs.SIGLEAvailable from TIB Hannover: FR 5297 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman