IMOS - OceanCurrent - Gridded sea level anomaly - Delayed mode - DM01 (superseded)

Gridded (adjusted) sea level anomaly (GSLA), gridded sea level (GSL) and surface geostrophic velocity (UCUR,VCUR) for the Australasian region. GSLA is mapped using optimal interpolation of detided, de-meaned, inverse-barometer-adjusted altimeter and tidegauge estimates of sea level. GSL is GSLA plus an estimate of the departure of mean sea level from the geoid - mean sea level (over 18 years of model time) of Ocean Forecasting Australia Model version 3 (OFAM3). The geostrophic velocities are derived from GSLA and the mean surface velocity from OFAM3. The altimeter data window for input to the Delayed Mode (DM) maps is symmetrical about the map date. The width of the window is dependent on the number of altimeters flying at the time and ranges from 30 days to 14 days. The altimeter data window for Near Real Time (NRT) maps is asymmetrical about the analysis date (-21 to 4 days). For both NRT and DM, altimeter data is weighted by the difference between the analysis date of the map and the time of each altimeter observation.DM01 - Delayed Mode GSLA version 01DM01 GSLA is a complete update of the previous version, DM00. With the growing time series of altimeter data, there have been considerable improvements to the corrections used to derive sea level anomaly (SLA). DM01 uses the latest altimeter data corrections (as of March 2018) to revise all daily maps from 1993-2019. Since June 2020, this DM01 product has been available via the AODN Portal, and supersedes the DM00 product formerly provided. The DM00 data is no longer updated, and is still available via https://catalogue-imos.aodn.org.au:443/geonetwork/srv/api/records/3162c844-d45c-491c-b326-6ae37e4079f9.Since April 2023, this DM01 product has no longer been updated, and is now unavailable via the AODN Portal. This product was superseded by the DM02 product, available via https://catalogue-imos.aodn.org.au/geonetwork/srv/api/records/da30c0b8-4978-4a26-915e-b80c88bb4510. References: http://oceancurrent.imos.org.au/

本数据集涵盖澳大拉西亚（Australasian）区域的网格化校正海平面异常（Gridded Adjusted Sea Level Anomaly, GSLA）、网格化海平面（Gridded Sea Level, GSL）以及地表地转流速度（UCUR、VCUR）。
GSLA通过对经潮汐校正、去均值处理、反气压校正的高度计与验潮仪海平面估算值开展最优插值成图。
GSL由GSLA叠加平均海平面相对于大地水准面的偏差估算值得到，该偏差取自澳大利亚海洋预报模型第3版（Ocean Forecasting Australia Model version 3, OFAM3）18年模拟时段的平均海平面数据。
地表地转流速度由GSLA与OFAM3的平均地表流速推导而来。
用于延迟模式（Delayed Mode, DM）成图的高度计数据窗口以成图日期为中心呈对称分布，窗口宽度取决于当前在轨运行的高度计数量，范围为14至30天。
近实时模式（Near Real Time, NRT）成图所用的高度计数据窗口以分析日期为中心呈非对称分布，时间跨度为-21至4天。
无论延迟模式还是近实时模式，高度计数据均根据成图分析日期与各高度计观测时刻的差值进行加权处理。
DM01——延迟模式GSLA版本01，是前代版本DM00的全面更新版本。随着高度计数据时间序列的不断丰富，用于推导海平面异常（Sea Level Anomaly, SLA）的校正方法得到了显著改进。DM01采用截至2018年3月的最新高度计数据校正方案，对1993年至2019年的所有逐日成图结果进行了修订。自2020年6月起，该DM01产品可通过澳大利亚海洋数据网络门户（Australian Ocean Data Network Portal, AODN Portal）获取，并取代了此前提供的DM00产品。DM00数据集不再更新，但仍可通过https://catalogue-imos.aodn.org.au:443/geonetwork/srv/api/records/3162c844-d45c-491c-b326-6ae37e4079f9获取。
自2023年4月起，该DM01产品不再更新，且已无法通过AODN Portal获取。其已由DM02产品取代，DM02产品可通过https://catalogue-imos.aodn.org.au/geonetwork/srv/api/records/da30c0b8-4978-4a26-915e-b80c88bb4510获取。
参考文献：http://oceancurrent.imos.org.au/