Auxiliary data from SIMBA-type sea ice mass balance buoy 2016T42

Temperature and heating-induced temperature differences were measured along a chain of thermistors. SIMBA 2016T42 (a.k.a. Awi_88) is an autonomous instrument that was installed on drifting sea ice in the Antarctic Ocean during the expedition Polarstern PS96 (ANT31/2,FROSN) in 2015/16. The thermistor chain was 5 m long and included 240 sensors with a regular spacing of 2 cm. The resulting time series describes the evolution of temperature and temperature differences after two heating cycles of 30 and 120 s as a function of location, depth and time between 2016-01-18 11:05:00 and 2017-01-08 15:29:00. Sample intervals are commonly between 1 and 24 hours, but most frequently hit intervals of 6 hours for temperature and 24 hours for temperature differences. The data set has been processed and contains quality flags for different kinds for erroneous data. Flag values are the sum of individual error codes. The value of 0 refers to no error. Quality flag, position: The geographic position is flagged +1 if the drift velocity, as derived from the GPS longitude and latitude, exceeds a threshold of 10 deg latitude or 50 deg longitude per time step; +2 if the position exceeds extreme values, such as longitude > 360 deg; +4 if the position is exactly 0.0. This instrument was deployed as part of the project Advanced Remote Sensing – Ground-Truth Demo and Test Facilities (ACROSS) Sea Ice Physics @ AWI (AWI_SeaIce)

Temperature measurements from SIMBA-type sea ice mass balance buoy 2016T42

Temperature and heating-induced temperature differences were measured along a chain of thermistors. SIMBA 2016T42 (a.k.a. Awi_88) is an autonomous instrument that was installed on drifting sea ice in the Antarctic Ocean during the expedition Polarstern PS96 (ANT31/2,FROSN) in 2015/16. The thermistor chain was 5 m long and included 240 sensors with a regular spacing of 2 cm. The resulting time series describes the evolution of temperature and temperature differences after two heating cycles of 30 and 120 s as a function of location, depth and time between 2016-01-18 11:05:00 and 2017-01-08 15:29:00. Sample intervals are commonly between 1 and 24 hours, but most frequently hit intervals of 6 hours for temperature and 24 hours for temperature differences. The data set has been processed and contains quality flags for different kinds for erroneous data. Flag values are the sum of individual error codes. The value of 0 refers to no error. Quality flag, position: The geographic position is flagged +1 if the drift velocity, as derived from the GPS longitude and latitude, exceeds a threshold of 10 deg latitude or 50 deg longitude per time step; +2 if the position exceeds extreme values, such as longitude > 360 deg; +4 if the position is exactly 0.0. This instrument was deployed as part of the project Advanced Remote Sensing – Ground-Truth Demo and Test Facilities (ACROSS) Sea Ice Physics @ AWI (AWI_SeaIce)

Temperature and heating induced temperature difference measurements from the sea ice mass balance SIMBA 2016T42

Temperature and heating-induced temperature differences were measured along a chain of thermistors. SIMBA 2016T42 (a.k.a. Awi_88) is an autonomous instrument that was installed on drifting sea ice in the Antarctic Ocean during the expedition Polarstern PS96 (ANT31/2,FROSN) in 2015/16. The thermistor chain was 5 m long and included 240 sensors with a regular spacing of 2 cm. The resulting time series describes the evolution of temperature and temperature differences after two heating cycles of 30 and 120 s as a function of location, depth and time between 2016-01-18 11:05:00 and 2017-01-08 15:29:00. Sample intervals are commonly between 1 and 24 hours, but most frequently hit intervals of 6 hours for temperature and 24 hours for temperature differences. The data set has been processed and contains quality flags for different kinds for erroneous data. Flag values are the sum of individual error codes. The value of 0 refers to no error. Quality flag, position: The geographic position is flagged +1 if the drift velocity, as derived from the GPS longitude and latitude, exceeds a threshold of 10 deg latitude or 50 deg longitude per time step; +2 if the position exceeds extreme values, such as longitude > 360 deg; +4 if the position is exactly 0.0. This instrument was deployed as part of the project Advanced Remote Sensing – Ground-Truth Demo and Test Facilities (ACROSS) Sea Ice Physics @ AWI (AWI_SeaIce)

Snow depth, sea ice thickness and interface temperatures derived from measurements of SIMBA buoy 2016T42

The Snow and Ice Mass Balance Array (SIMBA) is a thermistor string type IMB (Jackson et al., 2013) which measures the environmental temperature SIMBA-ET and a temperature change around the thermistors after a weak heating is applied to each sensor (SIMBA-HT). SIMBA 2016T42 (a.k.a. Awi_88) is an autonomous instrument that was installed on drifting sea ice in the Antarctic Ocean (Polarstern PS96 (ANT31/2, FROSN) in 2015/16) as part of the project Advanced Remote Sensing – Ground-Truth Demo and Test Facilities (ACROSS), Sea Ice Physics @ AWI (AWI_SeaIce). Its thermistor chain is 5 m long, and equipped with 240 thermistors (Maxim Integrated DS28EA00) at a spacing of 2 cm. Based on a manual classification method, the SIMBA-ET and SIMBA-HT were processed to obtain snow depth and ice thickness (smoothed with a 3-day running mean), as well as the thermistor number, the vertical position Z relative to the snow-ice interface and the measured SIMBA-ET at each detected interface (atmosphere-snow, snow-ice and ice-ocean) for the period between 2016-01-18T14:00:39 and 2016-12-23T08:00:39. To do this, we combined two derivatives of measured temperatures (the ET vertical gradient and HT rise ratio) to reduce the detection uncertainty of all interfaces considered. The snow or ice surface, consequentially the snow depth, is determined by the ET vertical gradient. Potential formation of snow ice is not explicitly considered in this data set, but may occur as depicted by vertical changes of the snow-ice interface position. The ice-ocean interface is usually determined using the HT rise ratio and serves as the lower limit for ice thickness. Overall, the accumulated error is 2 to 4 times the sensor spacing for both the snow depth and ice thickness. For interface temperatures, individual sensors in the chain measure with a temperature resolution of 0.0625°C, with the overall accuracy landing in the range of ± 2°C (Jackson et al., 2013). After the snow cover has melted, negative values for snow depth may indicate the onset of ice surface melt

Heating induced temperature difference measurements from SIMBA-type sea ice mass balance buoy 2016T42: 120 s after the heating cycle

Temperature and heating-induced temperature differences were measured along a chain of thermistors. SIMBA 2016T42 (a.k.a. Awi_88) is an autonomous instrument that was installed on drifting sea ice in the Antarctic Ocean during the expedition Polarstern PS96 (ANT31/2,FROSN) in 2015/16. The thermistor chain was 5 m long and included 240 sensors with a regular spacing of 2 cm. The resulting time series describes the evolution of temperature and temperature differences after two heating cycles of 30 and 120 s as a function of location, depth and time between 2016-01-18 11:05:00 and 2017-01-08 15:29:00. Sample intervals are commonly between 1 and 24 hours, but most frequently hit intervals of 6 hours for temperature and 24 hours for temperature differences. The data set has been processed and contains quality flags for different kinds for erroneous data. Flag values are the sum of individual error codes. The value of 0 refers to no error. Quality flag, position: The geographic position is flagged +1 if the drift velocity, as derived from the GPS longitude and latitude, exceeds a threshold of 10 deg latitude or 50 deg longitude per time step; +2 if the position exceeds extreme values, such as longitude > 360 deg; +4 if the position is exactly 0.0. This instrument was deployed as part of the project Advanced Remote Sensing – Ground-Truth Demo and Test Facilities (ACROSS) Sea Ice Physics @ AWI (AWI_SeaIce)

Heating induced temperature difference measurements from SIMBA-type sea ice mass balance buoy 2016T42: 30 s after the heating cycle

Temperature and heating-induced temperature differences were measured along a chain of thermistors. SIMBA 2016T42 (a.k.a. Awi_88) is an autonomous instrument that was installed on drifting sea ice in the Antarctic Ocean during the expedition Polarstern PS96 (ANT31/2,FROSN) in 2015/16. The thermistor chain was 5 m long and included 240 sensors with a regular spacing of 2 cm. The resulting time series describes the evolution of temperature and temperature differences after two heating cycles of 30 and 120 s as a function of location, depth and time between 2016-01-18 11:05:00 and 2017-01-08 15:29:00. Sample intervals are commonly between 1 and 24 hours, but most frequently hit intervals of 6 hours for temperature and 24 hours for temperature differences. The data set has been processed and contains quality flags for different kinds for erroneous data. Flag values are the sum of individual error codes. The value of 0 refers to no error. Quality flag, position: The geographic position is flagged +1 if the drift velocity, as derived from the GPS longitude and latitude, exceeds a threshold of 10 deg latitude or 50 deg longitude per time step; +2 if the position exceeds extreme values, such as longitude > 360 deg; +4 if the position is exactly 0.0. This instrument was deployed as part of the project Advanced Remote Sensing – Ground-Truth Demo and Test Facilities (ACROSS) Sea Ice Physics @ AWI (AWI_SeaIce)