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

Brief description

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.XXXX
1st 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 10
3rd 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 Code
Run Number from the GC
Counts - GC generated raw data
Log Counts - logarithmic conversion of the count data
Log -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 Sulfur
NaOH - NaOH adjustment
ngS/L - adjustment per litre
nM-DMSP/L - nanoMol's DMSP per litre
nm-DMS/L - nanoMol's DMS per litre

September 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 The method has since been superseded and the data here probably displays inaccuracies as a result of the analytical method used.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.

Lineage

Progress Code: completed

Statement: Raw data set of triplicate values only. All calibration data included. No statistical quality control included here, advice from technical contact should be sought prior to viewing or subsequent use.

September 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.