Methodology:

The data were collected with a thermistor deployed in the deepest part of a tidepool on East Beach, Rothera Point, Antarctica. The thermistor measured water temperature every 10 seconds, and these data were averaged every two minutes. The two-minute average was stored, yielding 720 data points for every 24 hour period. Data collection started on 3 February 1999, and continued until the thermistor failed on 13 May 2000, with a gap in the data from 17 to 29 June 1999, caused by a battery failure. Occasional out-of-range data (recorded as -6999) were recoded as missing data (*).

Data collection:

Data were recorded with a Campbell CR10 data logger, SM19 data storage module and Campbell 107 thermistor probe. Daily statistics were calculated with Minitab (version 18: www.minitab.com).

Data quality:

Immediately after download, the daily mean, minimum and maximum temperatures were calculated and stored as a separate data set. When the data were reanalysed (in 2019) these statistics were recalculated from the raw (2-minute average) data; the statistics were identical to those calculated after download. In 2019 two blocks of raw data were found to be unreadable and unrecoverable, and so only the daily statistics calculated after download are available. Data missing from 1999-06-20 to 1999-06-29 (battery failure)

For two periods, 1999-03-01 to 1999-03-19 and 1999-06-01 to 1999-06-19, only daily summary statistics available