Spatial and temporal distribution of sea salt aerosol mass concentrations in the marine boundary layer from the Arctic to the Antarctic

• Main Author: JIANG, B (via Mendeley Data)
• Language: unknown
• Published: 2021
• Subjects: Interdisciplinary sciences; Antarctic; Arctic; Merra; The Antarctic; Antarc*
• Online Access: http://nbn-resolving.org/urn:nbn:nl:ui:13-dj-ts8q; https://easy.dans.knaw.nl/ui/datasets/id/easy-dataset:197867

1. Sampling information The samples were collected from the Chinese Research Vessel (R/V) Xuelong, which undertook eight Antarctic cruises and five Arctic cruises, in summer, between 2008 and 2018. Briefly, all cruises used a large-flow air sampler to collect TSP (total suspended particulates) samples as well as field blanks. To avoid contamination, the large flow samplers were placed on the top deck during all cruises. All samples were collected using the relevant filter at a flow rate of 1.05 m3/min up to 57 h (most of them are 24h). After sampling, the samples were stored in a refrigerator at - 4 °C, prior to laboratory analysis. 2.Ion chromatography 467 samples were measured for ion concentrations. In summary, a punch sample of each filter was extracted by sonication and filtered through pre-washed 0.22-µm filters. Na+ in the samples was measured by ICS-2100 ion chromatography (Thermo Fisher Scientific Inc., USA). Each test had at least two reagent blanks, two field blanks, and one recovery. The recovery rate of all recovered samples was between 90% and 110%. The typical analytical precision of the instrument was better than 10 % relative standard deviation (RSD) for all ions. For comparison between the GEOS-Chem model and the observations, we converted the observed Na+ mass concentrations to SSA mass concentrations using a factor of 3.256, based on the mass ratio of Na+ in seawater. 3.GEOS-Chem model The GEOS-Chem global tropospheric chemistry model v12.2.6 (http://acmg.seas.harvard.edu/geos/) was used to simulate SSA concentrations with a spatial resolution of 2° × 2.5° at an hourly resolution (Text S3). Briefly, the model is driven by the Modern-Era Retrospective Analysis for Research and Applications-2 (MERRA-2). As our samples were TSP samples, the default SSA radius setting in the model (dp: particle diameter ~16 µm) was selected. SSA source functions in GEOS-Chem with an empirical dependence on SST derived by Jaegle et al. (2011). We simulated SSA concentrations every hour along the specific ship ...