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  • The dataset records ice coast and ice shelf front positions and hence change for the period 1843 to 2008. Archival maps, aerial photographs and satellite images of the Antarctic Peninsula were used to reveal the past shape of the ice coastline. The coastlines were mapped in a GIS (ESRI Arc/Info) using a mosaic of Landsat TM imagery as a common reference. Over 2000 aerial photographs and over 100 satellite images were used to compile the dataset that includes the fronts of 244 glaciers and 20 ice shelves on the Antarctic Peninsula. As the coastlines were digitised on-screen, metadata for each coast segment were added to the attribute table. The dataset is part of a wider project by the U.S. Geological Survey to record coastal-change for the whole continent.

  • Ground-penetrating radar (GPR) was used to test glacier ice thickness/glacier bed detectability on debris-covered Himalayan glaciers at a range of frequencies in glacier long- and cross- profiles and at static points. The survey sites were of the Lirung and Langtang Glaciers in the Langtang National Park, Nepal, where debris cover thickness varied from centimetres to several metres. The radar used was the BAS DELORES dipole pulse radar system, operating at 5MHz, 10MHz, 20MHZ and 40MHz. Data were acquired as a stop-go survey at 2-4m intervals on partially snow-covered and entirely debris-covered glacier surfaces in temperatures close to freezing, with a diurnal freeze-thaw cycle. Funding was provided by the NERC grant NE/L013258/1.

  • Between December 2012 and March 2013, snow measurements were conducted in 3 snow pits at both Gourlay Snowfield and Tuva Glacier, Signy Island, to determine the bacterial diversity within the snowpacks. Sites are denoted ''TX'' and ''GY'', where ''X'' and ''Y'' are numbers representing one of nine snowpits in a grid at Tuva and Gourlay respectively. Snow samples of the ''top'' layer were taken from the surface snow layer at a depth of 0 to 20 cm from the surface; snow samples of the middle ''mid'' layer were taken from 20 cm to the bottom of the snow pit; and samples from the ''ice'' layer were taken from the superimposed ice at the bottom of the snow pit. Snow and ice samples were collected from these pits and transported frozen to the UK for further analysis. Funding was provided by the NERC grants NE/H014446/1 and NE/H014802/1.

  • Between December 2012 and March 2013, snow measurements were conducted in 3 snow pits at both Gourlay Snowfield and Tuva Glacier, Signy Island, to determine the primary and bacterial production within the snowpacks. Sites are denoted ''TX'' and ''GY'', where ''X'' and ''Y'' are numbers representing one of nine snowpits in a grid at Tuva and Gourlay respectively. Snow samples of the ''top'' layer were taken from the surface snow layer at a depth of 0 to 20 cm from the surface; snow samples of the middle ''mid'' layer were taken from 20 cm to the bottom of the snow pit; and samples from the ''ice'' layer were taken from the superimposed ice at the bottom of the snow pit. Snow samples of the top and middle layer only were used for primary production, whilst bacterial production also included the lower ice layer. Samples collected from the pits were processed at Signy Station laboratory before being transported to the UK for further analysis. Funding was provided by the NERC grants NE/H014446/1 and NE/H014802/1.

  • Between December 2012 and March 2013, snow measurements were conducted at both Gourlay Snowfield and Tuva Glacier, Signy Island. Sites are denoted ''TX'' and ''GY'', where ''X'' and ''Y'' are numbers representing one of nine snowpits in a grid at Tuva and Gourlay respectively. Measurements include snow water equivalent and chemical properties. Snow thickness was measured during the surveys (and opportunistically following fresh snowfall events) at all 18 snow pits using an avalanche probe (average of 3 readings per sampling site). Snow density was also assessed at each site using a 1L pvc. snow tube. The thickness of the superimposed ice was measured at the beginning and at the end of the season after excavation using an ice axe. In order to calculate the proportion of the total winter accumulation that was transformed into superimposed ice by refreezing, its density was assumed to be 0.9 kg L-1. Three surveys at each of the 18 sites were conducted for biogeochemical conditions: ''top'' refers to the upper 20cm; ''mid'' refers to the rest of the snow; and ''ice'' is the basal ice (refrozen snowmelt on top of last summer''s surface). Key chemical properties determined include pH, dissolved organic carbon, total dissolved inorganic carbon, ammonium, chlorophyll and major ions. Funding was provided by the NERC grants NE/H014446/1 and NE/H014802/1.