Geodetic data records (GDRs) from the GEOSAT Exact Repeat Mission (ERM) from 22 October 1988 to 24 November 1988 (NODC Accession 8900003)

This accession contains one month of geodetic data records (GDRs) from the GEOSAT Exact Repeat Mission (ERM) for the time period of October 22, 1988 to November 24, 1988. Parameters include: time, orbit, latitude/longitude, and sea surface height. Corrections to the data include: sea level, wind and wave data, tides, dry and wet troposphere, ionosphere, height bias, altimeter crossover differences, altimeter sea surface measurement, and spacecraft orientation. These data were submitted by the U.S. Navy via National Oceanic Service.

The US Navy Geosat (Geodetic Satellite) radar altimeter mission lasted for nearly 5 years (March 1985 to January 1990) and collected approximately 750 million measurements of sea level, wave height, and wind speed over the global oceans. During the Geodetic Mission (March 1985 to September 1986), the satellite did not repeat its ground track for the duration of the mission. The orbit of the satellite was changed in early October 1986 to begin the Exact Repeat Mission (ERM) which lasted from November 1986 until the satellite quit functioning in January 1990. During the ERM, the satellite repeated its ground track every 17 days. Data were initially processed by the Johns Hopkins University Applied Physics Laboratory in Laurel, MD in coordination with the NOAA/NOS Satellite Altimeter Group. Data products were transferred to the NOAA National ceanographic Data Center (NODC) for distribution. Data products are archived at the NODC.

本存档包包含1988年10月22日至1988年11月24日期间，GEOSAT精确重复任务（Exact Repeat Mission, ERM）产生的一个月大地测量数据记录（geodetic data records, GDRs）。数据集参数涵盖时间、轨道、经纬度以及海面高度。数据校正项包括：海平面、风浪数据、潮汐、干/湿对流层、电离层、高度偏差、高度计交叉点差值、高度计海面测量值以及航天器姿态相关校正。本数据集由美国海军通过国家海洋局提交。

美国海军大地卫星（Geodetic Satellite, GEOSAT）雷达高度计任务持续近5年（1985年3月至1990年1月），在全球海洋范围内采集了约7.5亿条海平面、浪高及风速观测数据。在大地测量任务阶段（1985年3月至1986年9月），卫星轨道在任务周期内未重复覆盖地面轨迹。1986年10月初，卫星轨道进行调整，正式启动精确重复任务（ERM），该任务从1986年11月持续至1990年1月卫星停止运行。在ERM任务阶段，卫星每17天重复一次地面轨迹。数据最初由马里兰州劳雷尔市的约翰·霍普金斯大学应用物理实验室联合美国国家海洋和大气管理局/国家海洋服务卫星高度计小组进行处理。数据产品随后移交至美国国家海洋和大气管理局国家海洋数据中心（NODC）进行分发，且所有数据产品均存档于该中心。