DOI: 10.5061/dryad.d7wm37q6z
title: Statistics of bubble plumes generated by breaking surface waves

description: This dataset is an accompaniment to the paper titled "Statistics of
 bubble plumes generated by breaking surface waves" by Derakhti et al,
 in the Journal of Geophysical Research: Oceans. It includes extensive
 observations from arrays of freely drifting SWIFT buoys and shipboard
 systems, enabling concurrent high-resolution measurements of wind, waves,
 and bubble plumes. This dataset allowed us to examine the dependence of
 the penetration depth and fractional surface area (e.g., whitecap
 coverage) of bubble plumes generated by breaking surface waves on various
 wind and wave parameters over a wide range of sea state conditions in the
 North Pacific Ocean, including storms with sustained winds up to 22 m s-1
 and significant wave heights up to 10 m.  Notably, this study
 provides the first field evidence of a direct relation between bubble
 plume penetration depth and whitecap coverage, suggesting that the volume
 of bubble plumes could be estimated by remote sensing techniques.
description: This dataset was collected during an 18-day research cruise in
 the North Pacific Ocean in December 2019. The primary objective of the
 cruise was to conduct concurrent observations of breaking surface gravity
 waves and associated bubble plume statistics. A secondary objective was
 the replacement of a long-term moored wave buoy at Ocean Station PAPA
 (50°N, 145°W), which was reported as CDIP 166 and NDBC 46246. Hereafter,
 we refer to this dataset and cruise with the abbreviation PAPA. The PAPA
 cruise, conducted aboard the R/V <em>Sikuliaq</em>, departed
 Dutch Harbor, AK, on 5 December 2019 and ended in Seattle, WA, on 23
 December 2019. Arrays of SWIFT buoys were deployed from the ship early in
 the morning and usually recovered later the same day, with most shipboard
 and autonomous measurements occurring during local daylight hours.
 Eastward transits continued overnight. Raw SWIFT data were collected in
 bursts lasting 512 seconds, with intervals of 12 minutes. Processed SWIFT
 data, including wave spectra and bubble plume statistics, are produced for
 each burst for each buoy. Subsequently, concurrent bursts are averaged
 across the buoys, typically involving four of them. This dataset includes
 a total of 599 processed data points at 12-minute intervals, spread across
 14 daylight deployments. The statistics obtained from the shipboard
 measurements, such as wind speeds and whitecap coverage, represent
 10-minute average values at times that the processed SWIFT data points are
 produced.
description: # Statistics of bubble plumes generated by breaking surface waves
 [https://doi.org/10.5061/dryad.d7wm37q6z](https://doi.org/10.5061/dryad.d7wm37q6z) This dataset includes observations of wind, waves, air and sea temperatures, and acoustic backscatter from SWIFT buoys, along with shipboard measurements of wind speeds. Collected during an 18-day research cruise in the North Pacific Ocean in December 2019, the primary focus was on understanding breaking surface waves and associated bubble plumes. The dataset features over 2,000 bursts of SWIFT data processed at 12-minute intervals. The study also employed advanced Doppler sonar technologies for detailed bubble plume analysis. This dataset contains one file: **Derakhti_etal_2023_JGR_Data.mat** The dataset is organized into two primary structures: 1. **Derakhti2023JGR_ProcessedData**: This structure contains processed data collected by the drifting SWIFT buoys. Variable names that include “_v” indicate the statistics corresponding to the bubble plumes obtained using the bubble detection methods BDM2, as described in Section 2.5 of Derakhti et al. (2024). Below is a list of the variables, along with brief descriptions: * **Time**: Timestamps for each burst [number of days since January 0, 0000] * **Abp**: Proxy for the fractional surface area of bubble plumes * **Abp_v**: Proxy for the fractional surface area of bubble plumes * **Dbp_13**: Significant bubble plume depth [m] * **Dbp_v_13**: Significant bubble plume depth [m] * **Dbp_mean**: Mean bubble plume depth [m] * **Dbp_v_mean**: Mean bubble plume depth [m] * **Tbp**: Bubble plume residence time [s] * **Tbp_v**: Bubble plume residence time [s] * **Heq**: Equilibrium range significant wave height [m] * **Hp**: Peak wave height [m] * **Hs**: Total significant wave height [m]  * **Hs_ws**: Wind sea significant wave height [m] * **SWIFT_lat**: Latitude of the SWIFT buoys [deg] * **SWIFT_lon**: Longitude of the SWIFT buoys [deg] * **Tair**: Air temperature [C] * **Twater**: Surface water temperature [C] * **U10N**: 10-m neutral wind speed [m/s] * **W**: Whitecap coverage * **cm**: Linear wave phase speed corresponding to fm [m/s] * **cp**: Linear wave phase speed corresponding to fp [m/s] * **fm**: Spectrally-weighted mean frequency [1/s] * **fm_ws**: Wind sea spectrally-weighted mean frequency [1/s] * **fp**: Peak wave frequency [1/s] * **km**: Wave number corresponding to fm [1/m] * **mss**: Equilibrium range mean square slope * **mss_ws**: **mss** obtained from wind see components of wave spectra * **mss_over_dfeq**: Equilibrium range mean square slope divided by frequency range [s] * **mss_over_dfeq_ws**: **mss_over_dfeq** obtained from wind see components of wave spectra [s] * **ustar**: Air-side friction velocity [m/s] 2. **Derakhti2023JGR_ShipData**: * **Time**: Timestamps for each data point [number of days since January 0, 0000] * **U10_pl**: 10-m wind speed estimated based on a mean wind power law approximation and shipboard wind measurements [m/s] * **lat**: Latitude of the ship's position [deg] * **lon**: Longitude of the ship's position [deg] Note that NaN values represent missing data throughout the dataset.