----------------------------------------------------------------------------- ROSETTA-ICE DEEP ICE RADAR (DICE) LINE-BY-LINE PICKS PRODUCT (.MAT/.TXT/.JPG) ----------------------------------------------------------------------------- The ROSETTA-Ice Deep ICE Radar(DICE) data set contains ice thickness measurements of the Ross Ice Shelf in Antarctica using the IcePod. The ROSETTA-Ice project flew three campaigns for three consecutive years during November and December with the IcePod. A total of 43 flights were flown. The data set contains PNT measurements acquired from a Global Navigation Satellite System (GNSS) Inertial Navigation Systems (INS) system aboard the IcePod. Ice thickness measurements derived from layer (bright visible horizon) picking. Table 1. IcePod Deep ICE Radar (DICE) System & INS Receiver Type ---------------------------------------------------------------- The DICE is a pulsed-chirp depth-sounding radar system that is on board the IcePod. It was built and modified at the Lamont-Doherty Earth Observatory. The DICE has a 60MHz bandwidth with a power output of 1200W and a 188MHz center frequency. The PNT system that is on board the IcePod and used for SIR data processing is a NovAtel OEM/SPAN with SPAN LN200 IMU (POD-INS/SPAN). Table 2. Campaign, Project Year, and Description ------------------------------------------------ Campaign (Year): Description RS01 (2015): The first ROSETTA-Ice campaign was flown during November and December of 2015. RS02 (2016): The second ROSETTA-Ice campaign was flown during November and December of 2016. RS03 (2017): The third ROSETTA-Ice campaign was flown during November and December of 2017. --------------------------- File Format and Information --------------------------- The deep ice thicknesses are delivered in two formats: (1) Concatenated in Comma Separated Values file format (.csv). (2) Line-By-Line Picks Data Directories that contain directories with additional Pick Data: 'StitchedPicks' in space-delimited ASCII text file format (.txt), 'StitchedPicks' in MATLab file format (.mat), Picked & Unpicked Radar Frame Images in JPEG file format (.jpg), and an additional Read Me file, which is automatically generated with each Stitched Product. This data remains undecimated at 50hz. Surface Elevation is only delivered where a horizon has been picked. As such, the SurfElev variable is not representative of the actual flown DICE surface coverage. ---------------------- File Naming Convention ---------------------- The file naming convention for the thickness picks vary by data product. Examples for Line-By-Line Thickness Picks Directories are below: L650 --> ic_shallow_20180311_0123abcd --> jpg --> RS01_L650_20151123_102343_3usCh1_level2a_SIR_123_NoPicks.jpg --> RS01_L650_20151123_102343_3usCh1_level2a_SIR_123_Picks.jpg --> log --> generateStitchedProds20180311_162055.txt --> mat --> RS01_L650_20151123_102343_3usCh1_level2a_DICE_123-456_StitchedPicks.mat --> txt --> RS01_L650_20151123_102343_3usCh1_level2a_SIR_123-456_StitchedPicks.txt --> ___ --> --> ________ . jpg --> _________ . jpg --> --> __ . txt --> <.MATFileDirectory> --> ________ . mat --> --> ________ . txt Table 3.0: File Naming Convention for Line-By-Line .TXT & .MAT Thickness Picks ------------------------------------------------------------------------------ Variable: Description: Campaign ROSETTA-Ice Campaign Number Line Number ROSETTA-Ice Line Grid Identification Number YYYYMMDD Date of Survey / Data Collection (Year, Month, Date) hhmmss Time of Survey / Data Collection (hours, minutes, seconds) Pulse & Channel Frequency Radar Pulse Speed (3us) & Channel Frequency (Ch1) Processing Level Radar Processing Level Identifier Sensor Type IcePod Sensor Type Radar Frame Numbers Frame Numbers of Radar Data Contained in Concatenated File Concatenated Product Tag Identifier for Concatenated Full Resolution Radar Product Table 3.1: File naming Convention for Line-By-Line Radar Frame Image JPGs ------------------------------------------------------------------------- Variable: Description: Campaign ROSETTA-Ice Campaign Number Line Number ROSETTA-Ice Line Grid Identification Number YYYYMMDD Date of Survey / Data Collection (Year, Month, Date) hhmmss Time of Survey / Data Collection (hours, minutes, seconds) Pulse & Channel Frequency Radar Pulse Speed (3us) & Channel Frequency (Ch1) ProcessingLevel Radar Processing Level Identifier Sensor Type IcePod Sensor Type FileNum File Frame Identification Number. Data is processed in 30km(5minute) frames, each with an identification number. PickedProductTag Identifier for Picked Horizon Visible or Un-Picked in Image File DiffImageTag Identifier for Image with Differenced Filter ---------------------------- Data File Header Information ---------------------------- Table 4: Header Information for Line-By-Line .TXT & .MAT Thickness Picks ------------------------------------------------------------------------ Variable: Description: Lat_line Latitude of echo in degrees Lon_line Longitude of echo in degrees unixTime_line Unix seconds (slow-'along track' time) of each echo Number of seconds that have elapsed since 01 Jan 1970 00:00:00 UTC -leap seconds FlightElev_line Ellipsoid flight elevation in meters. If motion compensation is true, FlightElev is irrelevant SurfElev_line This is ellipsoid elevation of the surface Depth_line Depth of the horizon picked under the surface (thickness) calculated using cIce = 1.68e8 and along track TWTT Bright_line Signal power (dB) of the pixel. This is a relative number with 0 dB being some arbitrary value that is consistent as long as there a no significant changes with processing MotionComp Elevation correction is performed to this altitude (feet). If motion compensation is true, this is the flight elevation. FileNum File Frame Identification Number. Data is processed in 30km(5minute) frames, each with an identification number. ASCII (txt) Directory contains additional Read Me file that is automatically generated with each Stitched Product. --------- File Size --------- Line-By-Line Thickness Picks Directories range from approximately 16 MB to 112 MB. ---------------- Spatial Coverage ---------------- The approximate spatial coverage of the ROSETTA-Ice survey is below. Southernmost Latitude: 78° S Northernmost Latitude: 86° S Westernmost Longitude: 150° W Easternmost Longitude: 161° E ----------------- Temporal Coverage ----------------- 09 November 2015 to 04 December 2017 ROSETTA-Ice campaigns were conducted on an annual basis for three consecutive years during November and December with the IcePod. Table 5. IcePod Inertial Explorer Export Profiles and Sampling Rate ------------------------------------------------------------------- IcePod Inertial Explorer Export Profile: Sampling rate IcePod Deep ICE Radar : 50Hz IcePod Trajectory Standard: 200Hz -------- Contacts -------- Robin Bell Lamont-Doherty Earth Observatory of Columbia University 108E Oceanography 61 Route 9W - PO Box 1000 Palisades, NY 10964-8000 USA Email: robinb@ldeo.columbia.edu -------------------- Document Information -------------------- Document Creation Date: 24 May 2019 Document Revision Date: 16 December 2019