Australian bathymetry and topography grid depth contours, June 2009 (eAtlas, source: GA)

This dataset contains contours generated from the Australian bathymetry and topography grid, June 2009 version 4 by Geoscience Australia. It contains depth contours for -20m, -40m, -100m, -200m and -400m.Contours were generated in ArcMap using the Spatial Analyst Tools / Surface / Contour List tool. This output was then simplified using the Cartography Tools / Generalization / Smooth Line with a tolerance of 300m.The rest of this documentation is based on the metadata of the Australian bathymetry and topography grid itself. This grid is available from GA at http://dx.doi.org/10.4225/25/53D99B6581B9A .In 2005 Geoscience Australia and the National Oceans Office undertook a joint project to produce a consistent, high-quality 9 arc second (0.0025 deg or ~250m at the equator) bathymetric grid for Australian waters. In 2009 a number of new datasets were included in an updated version of the grid.The 2009 bathymetric grid of Australia has been produced to include recently acquired datasets, and solutions to issues identified in the previous version. The revised grid has the same extents as its 2005 counterpart, including the Australian water column jurisdiction lying between 92 deg E and 172 deg E, and 8 deg S and 60 deg S. The waters adjacent to the continent of Australia and Tasmania are included, as are areas surrounding Macquarie Island, and the Australian Territories of Norfolk Island, Christmas Island, and Cocos (Keeling) Islands. The area selected does not include Australia's marine jurisdiction offshore from the Territory of Heard and McDonald Islands and the Australian Antarctic Territory.This report details the datasets and procedures used to produce the 2009 bathymetric grid of Australia. As per the 2005 grid, the 0.0025 decimal degree (dd) resolution is only supported where direct bathymetric observations are sufficiently dense (e.g. where swath bathymetry data or digitised chart data exist) (Webster and Petkovic, 2005). In areas where no sounding data are available (in waters off the Australian shelf), the grid is based on the 2 arc minute ETOPO (Smith and Sandwell, 1997) and 1 arc minute ETOPO (Amante and Eakins, 2008) satellite derived bathymetry. The topographic data (on shore data) is based on the revised Australian 0.0025dd topography grid (Geoscience Australia, 2008), the 0.0025dd NZ topography grid (Geographx, 2008) and the 90m SRTM DEM (Jarvis et al, 2008).The final dataset has been provided in ESRI grid and ER Mapper (ers) formats. An associated shapefile has been produced so that the user can identify the input datasets that were used in the final grid.Data Location:This dataset is filed in the eAtlas enduring data repository at: data\other\AU_GA_Bathymetry-2009\derived\AU_e-Atlas-GA_Bathymetry-2009_Contours

本数据集包含由澳大利亚地球科学局（Geoscience Australia）发布的2009年第4版澳大利亚水深与地形网格生成的等高线。数据集包含-20m、-40m、-100m、-200m及-400m水深等值线。

等高线通过ArcMap中的空间分析工具/表面分析/等值线列表工具生成，随后使用制图工具/综合/平滑线工具以300米容差进行简化处理。

本数据集其余文档内容基于澳大利亚水深与地形网格本身的元数据。该网格可从澳大利亚地球科学局获取，链接为http://dx.doi.org/10.4225/25/53D99B6581B9A。

2005年，澳大利亚地球科学局与国家海洋办公室联合开展项目，旨在构建一套一致且高质量的9角秒（0.0025°，赤道处约250米）分辨率的澳大利亚海域水深网格。2009年，该网格的更新版本纳入了一批新数据集。

2009版澳大利亚水深网格纳入了最新获取的数据集，并修复了前一版本中发现的问题。修订后的网格与2005版具有相同的覆盖范围：涵盖东经92°至172°、南纬8°至60°之间的澳大利亚水域管辖区域，包括澳大利亚大陆与塔斯马尼亚岛周边海域、麦夸里岛周边区域，以及诺福克岛、圣诞岛和科科斯（基林）群岛等澳大利亚海外领地。本数据集未包含赫德岛和麦克唐纳群岛以及澳大利亚南极领地的近海海洋管辖区域。

本报告详述了用于生成2009版澳大利亚水深网格的数据集与处理流程。与2005版网格一致，0.0025十进制度（dd）分辨率仅在直接水深观测数据足够密集的区域（例如存在条带测深数据或数字化海图数据的区域）可用（Webster与Petkovic，2005）。在无测深数据的澳大利亚陆架外海域，该网格基于2弧分ETOPO（Smith与Sandwell，1997）和1弧分ETOPO（Amante与Eakins，2008）的卫星反演水深数据。陆上地形数据则基于修订后的澳大利亚0.0025dd地形网格（澳大利亚地球科学局，2008）、0.0025dd新西兰地形网格（Geographx，2008）以及90米分辨率SRTM DEM（Jarvis等人，2008）。

最终数据集以ESRI网格和ER Mapper（ers）格式提供。同时生成了关联的shapefile，以便用户识别用于构建最终网格的输入数据集。

数据存储位置：
本数据集存于eAtlas永久数据存储库的以下路径：dataotherAU_GA_Bathymetry-2009derivedAU_e-Atlas-GA_Bathymetry-2009_Contours