dune2_1_2026Gridded

generated 2026-08-17 17:18 UTC

Reports:SummaryStackGrid
Aquadopp:9920
Microcat:2941
Cruise
OdB
Ship
Odon de Buen
Latitude
65 43.913
Longitude
-27 48.000
Water depth
745 m
Deployment
2026-07-11 20:30 UTC
Recovery
2026-07-25 11:44 UTC
Duration
13d 15h
Samp. Δt
3600 s
Records
328
Grid ΔP
50 dbar
Pressure levels
15
Pressure range
100–800 dbar
Instruments
2
Source file
dune2_1_2026_grid.nc
oceanarray

(1) Processing history

(2) Hydrography

Temperature, salinity, dissolved oxygen, and O₂ saturation (when present). Vertically interpolated to regular pressure grid • 20 discrete colour levels.

show / hide hydro

(3) T-S diagram

Left: log₁₀(count+1) per T-S bin. Right (when O₂ present): median O₂ saturation per T-S bin — bins with <5 samples masked. Colour scale: BrBG (brown=low, teal=high).

show / hide ts_diagram

(4) Velocity

East, north, and up velocity. QC-flagged samples excluded before interpolation. Shared symmetric Spectral_r colormap for east/north; separate bounds for up. No temporal gap fill — NaN where no data.

show / hide vel_stacked

Velocity IQR profiles. Median (solid line) and interquartile range (shaded, 25–75 %) across the full deployment at each pressure level. 2.5–97.5 % outer envelope for speed. Right panel: count of non-NaN values per depth.

show / hide vel_iqr

Velocity time series at depth of maximum mean speed. Depth chosen as the pressure level with the highest time-mean current speed. Speed, east, and north velocity at that level.

show / hide vel_timeseries

(5) Velocity structure

Current roses. One rose per pressure level (up to 12, evenly subsampled). Suspect/bad QC excluded. Each petal shows the fraction of time current flowed in that direction; petal length encodes speed (m s⁻¹).

show / hide roses

Hodograph. Current hodographs at two pressure levels (25th and 75th percentile of the valid range). Top row = shallower level; bottom row = deeper level. Left = Tukey-smoothed raw; right = eddy component (LP mean removed). Colour indicates fractional time through the deployment (lime circle = start, red square = end). QC-bad data excluded.

show / hide hodograph

Particle trajectory. Pseudo-Lagrangian trajectories at each gridded pressure level, integrated from east and north velocity (Euler forward). All start at the origin. Coloured by pressure (dbar).

show / hide trajectory

(6) Stratification

Potential density. 20 discrete colour levels.

show / hide sigma0

Buoyancy frequency squared (N²). log₁₀(N²) in s⁻². Purple = strongly stratified; yellow = weakly stratified. Computed from T and S via GSW.

show / hide n2

(7) Overflow

Isopycnal coverage diagnostic. Percentage of time steps during which each σ₀ surface (0.1 kg m⁻³ spacing) lies within the measured column range. Green ≥ 80 %; amber 50–80 %; red < 50 %. Orange diamond = current --sig-level target. Dashed line = 80 % threshold. NaN gaps in the tracking figure above correspond to times when the isopycnal is outside the measured range (pycnocline above the shallowest grid level, or below the deepest).

show / hide isopycnal_coverage

Isopycnal height above seabed — sigma0. Height above seabed (m) of each target σ₀ surface through time. Tracked by linear interpolation in density space from the gridded sigma0 field; 1-hour running median applied. NaN where the surface outcrops or is outside the observed range. Light blue = lighter water (shallower); dark blue = denser water (deeper). Targets set by --sig-level (default σ₀ = 27.70).

show / hide isopycnal_ts_sigma0

Temperature ~100 m above seabed. 1-hour running median temperature at the grid pressure level nearest to 100 m above the seabed. Level and height-above-seabed shown in figure title.

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(8) Frequency analysis

Temperature power spectrum. Left: low-frequency overview — 14-day Hann windows, 50 % overlap. Right: high-frequency zoom — 1-day windows (~14× more windows, smoother tidal/inertial estimate); x-axis in hours. LF markers: M2, 1.8 d, 4 d, f. HF markers: M2 (12.4 h), f (inertial). Dashed black line: −2 spectral slope. Colour encodes pressure (light blue = shallow, dark blue = deep). Window length controllable via hf_segment_days in _make_spectrum_fig_b64.

show / hide temp_spectrum

Temperature wavelet scalogram. Continuous wavelet transform (Morlet, ω₀ = 6; Torrence & Compo 1998). Three depth levels: 2nd from top, middle, 2nd from bottom of the 100-dbar-multiple valid levels. Colour shows log₁₀(power) (°C² d); hatched grey region = cone of influence (edge-affected); hatched cross region = gap-filled data; black contour = 95 % significance against red noise.

show / hide wavelet

Rotary velocity spectrum. CW (clockwise, anticyclonic, solid red lines) and CCW (counter-clockwise, cyclonic, dashed blue lines) power spectra and rotary coefficient r = (CCW−CW)/(CCW+CW). Welch PSD, Hann window, 14-day segments, 50 % overlap. Up to 4 pressure levels (at most 1/5th of valid levels); colour encodes pressure depth. Vertical lines: M2, K1, 1.8 d, 4 d, and inertial period (f). r > 0 = CCW dominant; r < 0 = CW dominant. Physical interpretation (NH): inertial oscillations are inherently CW; for internal waves (f < ω), CW dominance indicates upward energy propagation / downward phase propagation (Leaman & Sanford 1975).

show / hide rotary_spectrum

(A) NetCDF variables

Variables — dune2_1_2026_grid.nc

VariableTypeDimsNValidMin / MaxUnitsLong nameStandard nameQC flag
conductivity float32 time, pressure 4,920 3,879 29.22 / 36.3 mS/cm Conductivity sea_water_electrical_conductivity
current_direction float32 time, pressure 4,920 3,511 1.051 / 359.3 degrees Current direction (0=N, clockwise) direction_of_sea_water_velocity
current_speed float32 time, pressure 4,920 3,511 0.0162 / 0.9045 m s-1 Horizontal current speed sea_water_speed
east_velocity float32 time, pressure 4,920 3,511 -0.8029 / 0.7687 m s-1 Eastward sea water velocity eastward_sea_water_velocity
north_velocity float32 time, pressure 4,920 3,511 -0.7064 / 0.7343 m s-1 Northward sea water velocity northward_sea_water_velocity
salinity float32 time, pressure 4,920 3,879 34.57 / 35.54 1 Practical Salinity sea_water_practical_salinity
sigma0 float32 time, pressure 4,920 3,879 27.43 / 28.05 kg m-3 Potential density anomaly referenced to surface (sigma-0) sea_water_sigma_t
temperature float32 time, pressure 4,920 4,201 -0.06961 / 8.025 degC Temperature sea_water_temperature
up_velocity float32 time, pressure 4,920 3,511 -0.2906 / 0.4569 m s-1 Upward sea water velocity upward_sea_water_velocity

Global attributes

AttributeValue
mooring_name dune2_1_2026
waterdepth 745
latitude 65 43.913
longitude -27 48.000
deployment_time 2026-07-11T20:30:00
recovery_time 2026-07-25T11:44:00
dt_seconds 3600
Conventions CF-1.13
p_start_dbar 100.0
p_end_dbar 800.0
dp_dbar 50.0