Marine National Facility (MNF) bathymetry voyage tracks - last 5 calendar years

There is an ongoing need for a national index of bathymetry survey coverage in Australian waters. The Marine National Facility (MNF) is Australia's dedicated blue-water research facility, and collects the largest body of publicly-accessible multibeam bathymetry (MBES) data in Australian waters. MNF survey data is routinely published in a raw (unprocessed) form shortly following MNF survey completion by CSIRO's Geophysical Survey and Mapping (GSM) group (https://www.cmar.csiro.au/data/gsm/). Geoscience Australia's AusSeabed initiative (https://ausseabed.gov.au/) works with CSIRO to make MNF MBES data available as maps and for download in gridded format at resolutions specified by the Australian Multibeam Guidelines (https://www.ausseabed.gov.au/__data/assets/pdf_file/0010/95887/Multibeam-Guidelines_v2.pdf). Once gridded MBES data is published, its survey coverage (spatial footprint) is collated into nationally aggregated bathymetry acquisitions maps (e.g. see https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/bfaac2bc-0c11-4991-b0fa-2a1dc7fd6e61). This spatial resource is important for research, marine managers, industry, and environmental impact assessment sectors as it provides an overview of the state of research knowledge of the physical seafloor environment in key areas of interest within Australia's vast marine estate.There is a considerable lag between MBES data being made available in L2 specialist format (typically ASCII XYZ), and being processed into a gridded format (e.g. GeoTIFF) following the Australian Multibeam Guidelines resolution specifications. This leaves some uncertainty about the location and coverage of more recently collected MBES data that has yet to be processed and publicly released in a gridded format.This dataset is a compilation of MNF voyage tracks (available through the CSIRO data trawler: https://www.cmar.csiro.au/data/trawler/) from the last 5 calendar years. The dataset will be periodically updated to reflect new voyage tracks; and to remove voyage tracks >5 years old. See 'Last Update' timestamp for an indication of currency. This record will be unpublished at such time that an automated process is developed to update national bathymetry survey coverage databases.

当前，澳大利亚海域亟需建立一套水深测量覆盖范围全国索引。澳大利亚国家海洋设施（Marine National Facility, MNF）是澳大利亚专属远洋研究设施，其所收集的公开可用多波束水深测量（multibeam bathymetry, MBES）数据体量为澳大利亚海域之最。澳大利亚联邦科学与工业研究组织（CSIRO）地球物理勘测与制图组（Geophysical Survey and Mapping, GSM）会在MNF勘测完成后，及时将原始（未处理）的MNF勘测数据公开发布（https://www.cmar.csiro.au/data/gsm/）。澳大利亚地球科学局（Geoscience Australia）主导的AusSeabed项目与CSIRO合作，将MNF采集的MBES数据按照《澳大利亚多波束测量指南》（https://www.ausseabed.gov.au/__data/assets/pdf_file/0010/95887/Multibeam-Guidelines_v2.pdf）规定的分辨率，制作为地图并以网格化格式提供下载（https://ausseabed.gov.au/）。网格化MBES数据发布后，其勘测覆盖范围（空间足迹）会被整合至全国汇总的水深勘测获取地图中（例如可参考：https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/bfaac2bc-0c11-4991-b0fa-2a1dc7fd6e61）。这类空间资源可为科研、海洋管理、产业及环境影响评估领域提供澳大利亚广阔海域内重点关注区域的海底物理环境研究现状概览，因此具有重要应用价值。

目前，MBES数据以L2专业格式（通常为ASCII XYZ格式）公开后，到按照《澳大利亚多波束测量指南》的分辨率要求处理为网格化格式（例如GeoTIFF格式），往往存在较长的时间滞后。这导致尚未完成处理并以网格化格式公开发布的最新采集MBES数据的位置与覆盖范围存在一定不确定性。

本数据集整合了近5个日历年度的MNF航行轨迹数据（可通过CSIRO数据拖网检索平台获取：https://www.cmar.csiro.au/data/trawler/）。本数据集将定期更新，以纳入新的航行轨迹数据，并移除超过5年的旧轨迹数据；更新时效性可参考“最后更新”时间戳。当开发出可自动更新全国水深测量覆盖范围数据库的流程后，本数据集将不再公开发布。