IMOS - SRS Satellite Altimetry Calibration and Validation Sub-Facility

IMOS - SRS 卫星测高校准和验证子设施

• 批准号: global : 78d588ed-79dd-47e2-b806-d39025194e7e
• 负责人: Watson, Christopher
• 金额: --
• 依托单位国家: 澳大利亚
• 财政年份: 2008
• 资助国家: 澳大利亚
• 起止时间: 2008-01-01 至 无数据
• 项目状态: 已结题
• 来源: https://researchdata.edu.au/imos-srs-satellite-sub-facility/955024
• 关键词: IMOS; SRS; Satellite; Altimetry; Calibration

High precision satellite altimeter missions including TOPEX/Poseidon (T/P), Jason-1 and now OSTM/Jason-2, have contributed fundamental advances in our understanding of regional and global ocean circulation and its role in the Earth's climate and regional applications. These altimeter satellites essentially observe the height of the global oceans – as such, they have become the tool of choice for scientists to measure sea level rise – both at regional and global scales as well as giving information about ocean currents and large- and small-scale variability. The determination of changes in global mean sea level is of fundamental importance in understanding the response of the ocean to a continuing warming climate – both through thermal expansion of the ocean, melting of the major ice sheets of Greenland and Antarctica, and mountain glaciers, and redistribution of water over the continents and atmosphere. As with all scientific observations, it is vital that the measurement tool is operating within its specifications – calibration and validation is therefore an important component in this regard. <br /> <br /> This IMOS sub-facility provides the sole southern hemisphere in situ calibration site to provide an ongoing calibration and validation data stream directly to the international (NASA and CNES sponsored) Ocean Surface Topography Science Team (OSTST). This contribution, importantly, spans multiple altimeter missions, thus enabling the assimilation of multi-mission satellite data to determine ongoing changes in sea level with flow-on effects to other uses of this data. The OSTST collectively oversees the operation and calibration of the precision altimetry missions, and ensures each of these missions is performing as accurately as possible in order to meet mission objectives. The IMOS supported calibration site in Australia is one of four primary in situ calibration/validation sites that contribute to the OSTST. The remaining sites include Harvest (USA), Corsica (France), and Gavdos (Greece). The Australian calibration site includes two comparison points where in situ data is compared against the altimeter – Bass Strait and Storm Bay. These two locations both lie on descending (N -&gt; S) pass 088 of the satellite altimeter, and thus share similar satellite orbit characteristics. The use of these two sites allows detailed investigation into the accuracy of the altimeter over two different wave climates. The average significant wave height at Storm Bay is approximately double that observed at the comparatively sheltered Bass Strait location. One of the ongoing issues with satellite altimeter missions is the “Sea-state bias” correction which is related to wave shape and height. We plan to use the different wave climates at the two locations, coupled with the fact that some other things (such as orbit errors) are the same at both locations to improve the quality of this correction.

高精度的卫星高度计，包括Topex/Poseidon（T/P），Jason-1和现在的OSTM/Jason-2，在我们对区域和全球海洋循环及其在地球气候和地区应用中的作用方面取得了基本进步。这些高度计的卫星基本上观察到全球海洋的高度 - 因此，它们已成为科学家在区域和全球范围内衡量海平面上升的首选工具，并提供了有关洋流和大型和小规模变化的信息。确定全球平均海平面的变化对于理解海洋对持续变暖气候的反应至关重要 - 无论是通过海洋的热膨胀，格陵兰和南极的主要冰层融化，以及山地冰川，以及在大陆和大气中的水重新分布。与所有科学观察一样，测量工具在其规范范围内运行至关重要 - 因此，校准和验证是这方面的重要组成部分。 <br /> <br /> 这种IMOS替代性提供了唯一的南半球原位校准位点，可直接向国际（NASA和CNES赞助的）海洋表面地形科学团队（OSTST）提供持续的校准和验证数据流。重要的是，这项贡献涵盖了多个高度计的任务，从而实现了多矿物卫星数据的同化，以确定海平面的持续变化，并通过流动效应对该数据的其他用途进行效果。 OSTST集体监督精度高度按任务的操作和校准，并确保这些任务中的每一个都尽可能准确地执行以实现任务目标。澳大利亚IMO支持的校准位置是有助于OSTST的四个主要原位校准/验证位点之一。其余的地点包括Harvest（美国），Corsica（法国）和Gavdos（希腊）。澳大利亚校准站点包括两个比较点，其中将原位数据与高度计 - 低音海峡和风暴湾进行了比较。这两个位置都位于卫星高度计的088上的下降（n-> s）上，因此具有相似的卫星轨道特征。使用这两个站点可以详细研究在两个不同的波气候上高度计的准确性。风暴湾的平均显着波高大约是在相对庇护的低音海峡位置观察到的两倍。卫星高度计任务的持续问题之一是与波形和高度有关的“海态偏见”校正。我们计划在两个位置使用不同的波气候，再加上两个位置的其他一些东西（例如轨道误差）是相同的，以提高此校正的质量。