Further by downloading this data the user acknowledges that they agree with the NERC data policy (), and the following conditions:

1. To cite the data in any publication as follows:

Corr, H., & Vaughan, D. (2020). Processed ice shelf base picks from airborne radar depth sounding across the Pine Island Glacier Ice Shelf (2010-2011) (Version 1.0) [Data set]. UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation. https://doi.org/10.5285/E88F651C-3389-4D99-8333-07872DCEAB57

2. The user recognizes the limitations of data. Use of the data is at the users' own risk, and there is no warranty as to the quality or accuracy of any data, or the fitness of the data for your intended use. The data are not necessarily fully quality assured and cannot be expected to be free from measurement uncertainty, systematic biases, or errors of interpretation or analysis, and may include inaccuracies in error margins quoted with the data.

Methodology:

Radar data and details of survey design and location are presented in Vaughan et al. (2012) and Dutrieux et al. (2013). Radar data were collected using the PASIN radar echo sounding system (table 1 (Corr et al., 2007)). Data provided here includes picks of surface and ice sheet bed elevation. Note a single flight may contain data from two or more SEGY files, identified in the SEGYname channel. Surface elevation is derived from radar altimeter for ground clearance < 750 m, and the PASIN system for higher altitudes.

Channel description:

Basic Channels Name Description

Date UTC date (YYYY/MM/DD)

Time UTC time (HH:MM:SS.SS)

FlightID Sequential flight number and survey ID e.g. W12

Line_no Line Number e.g. LW200.1

Lon Longitude WGS 1984

Lat Latitude WGS 1984

x x projected meters, coordinate system defined on location page

y y projected meters, coordinate system, defined on location page

Height_WGS1984 Aircraft altitude (meters) in WGS 1984

Radar

segy_name Radar_segy file name (BAS system).

TraceNum Radar segy trace number (BAS system).

PriNum Raw radar time (BAS system).

surfPickLoc Location down trace of surface pick (BAS system).

bedPickLoc Location down trace of bed elevation pick (BAS system).

surfElev Surface elevation

bedElev Ice bed elevation, derived by subtracting tice from surfElev

tIce Ice thickness, derived from bedPickLoc and surfPickLoc.

*Projected coordinates (x and y) are in Polar Stereographic:

Latitude of natural origin: -71

Longitude of natural origin: 0

Scale factor at natural origin: 0.994

False easting 0

False northing 2072760.109

Positioning for the PIG mouth survey used a dual-frequency carrier-phase GPS (Vaughan et al., 2012). Positions are calculated for the phase centre of the aircraft antenna. All positions (Lat, lon and height) are referred to the WGS1984 ellipsoid.