English utf8 dataset McMurdo Dry Valleys LTER http://mcmlter.org/ 2014-10-30 ISO 19115-2 Geographic Information - North American Profile Metadata - Data with Biological Extensions ISO 19115-2:2009(E) 2009-10 Sub-ice Current Velocities Recorded with an Acoustic Doppler Current Profiler 2014-10-30 publication Devin Castendyk Golder Associates Inc. https://www.golder.com castendn@gmail.com pointOfContact documentDigital On 7 January 2010, a SonTek Argonaut-XR 1.5 MHz Acoustic Doppler Current Profiler (ADCP) was fixed at the bottom of the lake ice in the Lake Hoare Limno Hole inside the Polar Haven, looking downward through the water column. Every 10 seconds, the ADCP measured horizontal and vertical current velocities in ten, 30-cm-thick cells between 0.5 and 3.5 m below the lake ice. Over 32.5 hours, horizontal currents in the shallowest cell (0.5 to 0.8 m below lake ice) had a mean speed of 23.8 cm/sec. This speed was independently validated by lowering a SonTek handheld Acoustic Doppler Velocity (ADV) meter into the ice hole. Horizontal speeds oscillated between 10.1 and 37.5 cm/sec over the course of the ADCP dataset. Fast Fourier Transforms of x-direction velocity data from the shallowest cell identified oscillation periods of 11, 3.7, and 2.5 minutes consistent with the theoretical first-mode longitudinal surface seiche in Lake Hoare. Current direction oscillated between N 78 degrees E and N 289 degrees E along the east-west longitudinal axis of the lake, consistent with the behavior of a seiche. Name: Hugh Gallagher Role: associated researcher completed McMurdo Dry Valleys LTER http://mcmlter.org/ English Lake Hoare occupies a narrower portion of the Taylor Valley, dammed by the Canada Glacier. It would drain almost completely without this dam. There are a number of islands which may be related to an old terminal of Canada Glacier. The lake is fed primarily from direct runoff from the glacier, as well as meltwater streams. (Lake level rose ~1.5 m between 1972 and 1996). There are no surface outflows; the only known water loss is through ice ablation (evaporation, sublimation and physical scouring). Valley: Taylor Distance to Sea : 15 Maximum Length (km): 4.2 Maximum Width (km): 1 Maximum Depth (m): 34 Surface Area (km^2): 1.94 Ice Thickness Average Surface (m): 3.1 - 5.5 Volume (m^3 * 10^6): 17.5 162.935836791992 162.784423828125 -77.639259338379 -77.623085021973 ground condition 2009-01-01 2010-12-31 Data contained in these files has been subjected to quality control standards imposed by the investigator. The user of this data should be aware that, while efforts have been taken to ensure that these data are of the highest quality, there is no guarantee of perfection for the data contained herein and the possibility of errors exists. If you encounter questionable data, please contact the MCM LTER data manager corrected or qualified. Thus, these data may be modified and future data will be appended. https://mcm.lternet.edu/sites/default/files/LIMNO_ANCILLARY_ADCP.csv LIMNO_ANCILLARY_ADCP eng; US McMurdo Dry Valleys LTER LIMNO_ANCILLARY_ADCP Record Delimiter : \n Number of Header Lines : 28 Number of Footer Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false DATASET_CODE A code used to identify the entity table name and create lists of data holdings LOCATION NAME Name of lake where measurement was made LOCATION CODE Location in the lake where measurement was made DATE_TIME Date on which sample was gathered Date Time Format: mm/dd/yy H:M:S MIN_DEPTH (m) Minimum Depth value for the measurement range MAX_DEPTH (m) Maximum Depth value for the measurement range SAMPLE_ID An internal identifier for the record Vx (cm/s) the velocity component for the X-axis - East-West, where positive values mean fluid moving towards the west Vy (cm/s) the velocity component for the Y-axis - North-South, where positive values mean fluid moving towards the north Vz (cm/s) the velocity component for the Z-axis - Bottom-Up, where positive values mean fluid moving towards the bottom (down) Spd_xy the magnitude of the velocity (the speed) on the horizontal plane for the x-axis Dir THe orientation of the velocity vector on the horizontal plane DBF https://mcm.lternet.edu/sites/default/files/LIMNO_ANCILLARY_ADCP.csv dataset Location: Limno Sample Hole, Lake Hoare, Taylor Dry Valley GPS: S77°37.660’, E162°54.572’ 7 January 2010, 10:50 p.m. to 9 January 2010, 7:24 a.m. (New Zealand Time). Duration: 32.5 hours Time correction: Add 18 hours to the raw data times to convert to the New Zealand Time Zone used in the McMurdo Dry Valleys and to synchronize sample times with other datasets provided on MCM-LTER web site. 7 - 9 January 2010 Methods and Settings ADCP fixed to a metal pole to minimize motion ADCP inverted and arrow aligned with North such that: +x is West, -x is East +y is North, -y is South +z is Down, -z is up True current direction (degrees from N) = 360 – observed direction ADCP lowered to the bottom of the limno ice hole top of ADCP near the ice-water interface. ADCP diagnostics test performed Tarp placed over sample hole during deployment Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used : Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used : Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m; Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m : Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m Number of cells: 10; Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m Number of cells: 10; Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m Number of cells: 10; Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m Number of cells: 10; Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m Number of cells: 10 Approximate depth range of ADCP cells: Averaging Interval: 10 seconds Sampling Interval: 10 seconds Quality of data: Good. ADCP resolution = plus/minus 0.1 cm/sec. ADCP accuracy = plus/minus 0.5 cm/sec. Files for standard deviations and signal-to-noise ratios provided. Total ice thickness: 3.3 m Distance from piezometric surface to base of ice: 2.8 m Date ice thickness measured: 7 January 2010 "Automatic Boundary Adjustment" used Coordinant system "XYZ" "Profile Mode" used Cell thickness: 0.3 m Number of cells: 10 Approximate depth range of ADCP cells: Rel. to bottom of the lake : Rel. to piezometric surface Cell 1: 0.5 to 0.8 3.6 to 3.9 Cell 2: 0.8 to 1.1 3.9 to 4.2 Cell 3: 1.1 to 1.4 4.2 to 4.5 Cell 4: 1.4 to 1.7 4.5 to 4.8 Cell 5: 1.7 to 2.0 4.8 to 5.1 Cell 6: 2.0 to 2.3 5.1 to 5.4 Cell 7: 2.3 to 2.6 5.4 to 5.7 Cell 8: 2.6 to 2.9 5.7 to 6.0 Cell 9: 2.9 to 3.2 6.0 to 6.3 Cell 10: 3.2 to 3.5 6.3 to 6.6 Supporting file links (Standard Deviations, etc) "ADCP set up 7- 9 January 2010 This text file lists more details about how data were recorded. Link here "ADCP signal to noise ratio 26-30 Dec 2012" This file provides diagnostic data on the instrument which someone might find useful. Link here "ADCP standard deviation 26-30 Dec 2012" This text file provides information on sampling error.Link Here Metadata Access Constraints: none Metadata Use Constraints: none annually McMurdo Dry Valleys LTER http://mcmlter.org/ pointOfContact