NRS-22019 | Tidal Records and Comparisons - Sydney, Newcastle and Wollongong Harbours and Parramatta River

A self-recording tide gauge was established at Fort Denison in 1867, and since that year a continuous record of tides has been kept.These charts show daily tidal movements recorded by tidal gauges, with many of the charts also including tidal gauge comparisons between the reading at Fort Denison and a number of other ports. Hourly tidal readings recorded on a daily basis over weekly and monthly periods showing tide hourly heights; daily tidal readings indicating am and pm high water and low water marks recorded on a monthly basis; tidal comparisons between different areas and at different times for one area; tidal predictions; calculations and analysis with working papers and reports on soundings and tidal comparisons; tide recordings after earthquakes; barograph readings and wind direction data. These records are used for measuring the mean high water mark (MHWM).Areas covered by these records include:Fort Denison, Camp Cove, Uhrs Point, The Spit, Clifton Gardens, Cockatoo Island, Cabarita, Bantry Bay, Duck River, Newington, Bradleys Head, Point Piper, Blackwattle Bay, Peats Ferry, Gladesville Bridge, Homebush Bay, Parramatta, Newcastle and Wollongong.

1867年，丹尼森堡（Fort Denison）设立了自记潮位计，自此便持续开展潮汐观测记录工作。
本批海图展示了由潮位计记录的每日潮汐变化，其中多数海图还包含了丹尼森堡与其他多个港口的潮位读数对比数据。
该数据集涵盖以下多类观测与分析内容：按周、月周期每日采集的逐时潮汐读数，用于呈现逐时潮高；按月度记录的每日潮汐读数，标注上午、下午的高潮位与低潮位；不同区域间以及同一区域不同时段的潮汐对比数据；潮汐预报结果；包含水深测量与潮汐对比分析的工作底稿及正式报告中的计算与分析内容；地震后的潮汐记录；气压计读数与风向数据。
上述记录均可用于测算平均高潮位（mean high water mark, MHWM）。
该数据集覆盖的区域包括：丹尼森堡、坎普湾（Camp Cove）、厄斯角（Uhrs Point）、斯皮特岬（The Spit）、克利夫顿花园（Clifton Gardens）、鹦鹉岛（Cockatoo Island）、卡巴里塔（Cabarita）、班特里湾（Bantry Bay）、达克河（Duck River）、纽因顿（Newington）、布拉德利角（Bradleys Head）、派珀角（Point Piper）、黑荆湾（Blackwattle Bay）、皮茨渡口（Peats Ferry）、格拉德斯维尔桥（Gladesville Bridge）、霍姆布什湾（Homebush Bay）、帕拉马塔（Parramatta）、纽卡斯尔（Newcastle）以及伍伦贡（Wollongong）。