CLIVASH2k initiates a data call of published and unpublished Antarctic ice core records of Na+ and SO42-, ideally as both flux and concentration, at the best available resolution (seasonal to decadal) spanning the past two thousand years. To submit data, please fill in the excel template (download here) by 1 December, send it to Elizabeth Thomas: This email address is being protected from spambots. You need JavaScript enabled to view it. and Diana Vladimirova: This email address is being protected from spambots. You need JavaScript enabled to view it. or contact us if you wish to be involved in the data interpretation or analysis. Thank you.