Southern Ocean pinnipeds provide bathymetric insights on the East Antarctic continental shelf

These are seal dive data used in the paper "Southern Ocean pinnipeds provide bathymetric insights on the East Antarctic continental shelf"The seal dive depths provide new ocean depth information from over 500,000 individual dives from 265 seals on the East Antarctica continental shelf. The seal tags have a post-processed position uncertainty of 2-3 km, and provide transmitted depth data with a resolution of 10-25 m. About 25% of these seal dives were, on average, 220 m (sometimes over 1000 m) deeper than the interpolated seafloor in the International Bathymetric Chart of the Southern Ocean Version 2Each row is an individual dive collected by a SMRU CTD-SLDR and transmitted via system Argos. Max_depth is the maximum depth reached by the seal on that dive. The lons and lats are estimates of the seals location at the end of that dive and were calculated using the AniMotum package in R, which uses a state Space Model to estimate a location for each dive. The uncertainty of these locations has been quantified to be a median error of 3.2 km (95th percentile = 12.1 km), relative to near-simultaneous GPS locations for the same seals (Jonsen, I. D. et al. A continuous-time state-space model for rapid quality control of Argos locations from animal-borne tags. Move. Ecol. 8, 31 (2020). https://doi.org:10.1186/s40462-020-00217-7). The columns are: Id = seal identifierdate = date/time in YYYY-mm-dd HH:MM:SS formatlon = longitudelat = latitudemax_depth = maximum depth of the dive. Depths are negative to match the IBCSO dataibcso2 = IBCSO V2 bathymetry at that pointdfb = distance from bathymetry calculated as ibcso2-depth, so that a positive value indicates the dive was deeper than IBCSOspecies= species of seal that collected the data (Mirounga leonina or Leptonchtyes weddellii)

本数据集为发表于论文"南大洋鳍足类动物为东南极大陆架提供水深测绘视角"（Southern Ocean pinnipeds provide bathymetric insights on the East Antarctic continental shelf）所用的海豹潜水数据。
该数据集依托东南极大陆架上265头海豹的50余万次独立潜水数据，获取了全新的海洋水深信息。
海豹搭载的标记设备经后处理后的位置不确定性为2-3千米，其传输的深度数据分辨率为10-25米。
其中约25%的潜水深度平均比南大洋国际水深图第二版（International Bathymetric Chart of the Southern Ocean Version 2，简称IBCSO V2）的插值海底高程高出220米，部分案例甚至超过1000米。
数据集中每一行代表一次由SMRU CTD-SLDR设备采集、经Argos系统传输的独立潜水数据。
Max_depth为该次潜水中海豹抵达的最大水深。
lons（经度）与lats（纬度）为该次潜水结束时海豹位置的估算值，通过R语言的AniMotum包计算得到，该工具依托状态空间模型（state space model）为每一次潜水估算对应位置。
经与同批海豹近乎同步的GPS定位数据比对，该类位置估算的不确定性经量化后显示：中位误差为3.2千米，95%分位数误差为12.1千米（数据来源：Jonsen I.D.等. 用于动物搭载标记设备Argos定位快速质控的连续时间状态空间模型. 运动生态学(Move. Ecol.), 8, 31(2020). https://doi.org:10.1186/s40462-020-00217-7）。
各字段含义如下：
- Id：海豹识别码
- date：日期/时间，格式为YYYY-mm-dd HH:MM:SS
- lon：经度（longitude）
- lat：纬度（latitude）
- max_depth：潜水最大水深，为与IBCSO数据格式保持一致，水深值以负数表示
- ibcso2：对应点位的IBCSO V2水深数据
- dfb：水深偏差值，计算公式为ibcso2 - max_depth，当该值为正时，表示本次潜水深度超过IBCSO V2的海底水深数据
- species：采集该数据的海豹物种，包括南象海豹（Mirounga leonina）或威德尔海豹（Leptonychotes weddellii，原文拼写为Leptonchtyes weddellii）