DMS, DMSP, DMSO measurements Minicosm Experiment, Davis 2002-03

Dimethylsulfide and its precursors and derivatives constitute a major sulfate aerosol source. This dataset incorporates the potential for increased UV radiation effects due to stratospheric ozone depletion over spring and summer in Antarctica, using large-scale incubation systems and 13-14 day incubation periods. Surface seawater (200 micron filtered) from the Davis coastal embayment was incubated during four experiments over the 2002-03 Antarctic Summer.The data incorporates seawater measurements of DMS, DMSP and DMSO over a temporal progression during each incubation experiment. Six polyethylene tanks of varying PAR and UV irradiances were incubated. Water was collected stored and analysed by gas chromatography according to a specific sampling protocol, employed by all investigators associated with the project. The data are organised according to analysis day, with each days calibration data displayed at the top of each sheet. The sample code is followed by GC run number and then the raw count data from the GC. This is calculated to nanomoles DMS, DMSP or DMSO.Sample Codes: Codes for temporal data follow format X.XXXX1st X gives experiment number, 1 to 4.2nd X gives sampling day, 0, 0.5, 1, 2, 4, 7, 14 (will result in digit code for day no. less than 103rd X gives tank number relating to irradiance level(one to six)4th and 5th X is replicate number, (01, 02, 03, DMS), (04, 05,06, DMSP total), (07, 08, 09, DMSP dissolved), (10, 11, 12, DMSO total).The fields in this dataset are:Sample CodeRun Number from the GCCounts - GC generated raw dataLog Counts - logarithmic conversion of the count dataLog -c - logarithmic conversion minus the y-intercept determined by calibration of the GC.(log -c)/m - log -c divided by m, determined by calibration of the GC.ngS anti log - nanograms of SulfurNaOH - NaOH adjustmentngS/L - adjustment per litrenM-DMSP/L - nanoMol's DMSP per litrenm-DMS/L - nanoMol's DMS per litreSeptember 2013 Update: DMSO was analysed in these experiments according to an adaptation of the sodium borohydride (NaBH4) reduction method of Andreae (1980). The method has since been superseded and the data here probably displays inaccuracies as a result of the analytical method used. This DMSO data should be treated with caution.