This dataset contains estimations of Arctic sea level anomalies produced by the ESA Sea Level Climate Change Initiative project (Sea_level_cci), based on satellite altimetry from the ENVISAT and SARAL/Altika satellites. It has been produced by Collecte Localisation Satellites (CLS) and the Plymouth Marine Laboratory (PML). The retrieval of sea level in the Arctic sea ice covered region requires specific processing steps of the satellite altimetry measurements. For this dataset, a specific radar waveform classification method has been applied based on a neural network approach, and the waveform retracking is based on a new adaptive retracking that is able to process both open ocean and peaky echoes measured in leads without introducing any bias between the two types of surfaces. Editing and mapping processing steps have been optimized for this dataset

Data relates to the NERC Urgency Grant NE/R00210X/1 which focusses on Sediment signatures of the 25 December 2016 Chile earthquake to constrain detection limits of tidal marsh records. The documentation provides an overview of findings from two field seasons to the southern coast of Isla de Chiloé, Chile, including field observations, sediment samples and surface vegetation surveys. The research locations for diatom analyses are Ayentema, Asasao, Inio and Quilanlar, southern Chiloé, Chile. Field season 1 (excluding travel dates): 2-9 August 2017 Field season 2 (excluding travel dates): 6-16 October 2017 Diatom data collection: through to 30 June 2018

A large number of charts (originals and copies) together with tabulations of data are also available, some of which date back to the 1850s. A more detailed description of these will be available once they have been systematically catalogued and archived.

A set of historical tide gauge sea level records from Santander (Northern Spain) have been recovered from logbooks stored at the Spanish National Geographical Institute (IGN). Sea level measurements have been digitised, quality-controlled and merged into a consistent sea level time series. Vertical references among instruments benchmarks have been derived from high precision vertical levelling surveys. The observations were recorded as daily averages and are from three different instruments in two locations in Santander (Spain). The historical sea level record in Santander consists of a daily time series spanning the period 1876-1924 and it is further connected to the modern tide gauge station nearby, ensuring datum continuity up to the present. The data from Santander comes from a floating gauge and then syphon gauges. This scarcity of long-term sea-level observations, as well as their uneven geographical distribution is a major challenge for climate studies that address, for example, the quantification of mean sea-level rise at centennial time scales, the accurate assessment of sea-level acceleration or the long-term changes in sea-level extremes that are vital for coastal risk assessments. This dataset represents an additional effort of sea-level data archaeology and aims at preserving the historical scientific heritage that has been up to now stored in old archives in non-electronic format. The research was partially funded by the Spanish Ministry of Science, Innovation and Universities. A further two series were rescued from Alicante under the same initiative.

The dataset consists of 2580 tiff images of tide gauge charts from Bowling, River Clyde. The images were taken from annual bound volumes of tide gauge charts (~1 page per week, 52 pages per volume). A typical volume measures 37 x 34 x 3.5 cm and pages are single sided. The ledgers for Bowling begin in 1888 and end in 1952, but under this project, only the charts up until 04/01/1939 were photographed. The trace on the original charts was generated by a float tide gauge. The float inside a stilling-well was connected by a wire run over pulleys to a pen that moved up and down as the tide rose and fell. The images were generated by a commercial scanning organisation (TownsWeb Archiving Ltd) using a planetary overhead book scanner. In July 2016 The Peel Group Ltd. (Glasgow) approached BODC to donate their tidal archive, due to office redevelopment. The archive consists of ledgers of tide gauge charts (345 annual bound volumes) and handwritten ledgers (91 bound books) from several locations along the Clyde, with the earliest record beginning in 1841 from Glasgow Harbour. Later that year BODC received a grant from the Marine Environmental Data and Information Network (MEDIN) to photograph a selection of the ledgers. MEDIN released these funds to support small Data Archiving Projects that increase access to industry marine data. Ledgers also exist for Broomielaw, Dalmuir, Gourock, Govan Wharf, Greenock, Partick Wharf Glasgow, Queen's Dock Entrance Glasgow and Rothesay Dock. Most begin in the late 19th Century and run to the mid-20th century. It is hoped that these will be digitised in the future, subject to funding.

This dataset contains high and low water values manually digitised from historic hand-written tabulated ledgers, from the Port of London Authority (PLA). The dataset contains 463 years of data, from across 15 tide gauge sites along the Thames Estuary (bounding box = -0.3159W, 51.3914N, 1.3797E, 51.8428N), for the period 1911 to 1995. When these historic records are combined with digital records available from the PLA since 1995, the new sea level time-series spans the 109-year period from 1911 to 2019. London is one of the world’s most important coastal cities and is located around the Thames Estuary. Quantifying changes in sea levels in the Thames Estuary over the 20th century and early part of the 21st century is vital to inform future management of flood risk in London. This dataset is of importance for ongoing monitoring of mean sea-level rise, and changes in tidal range and extreme sea levels in the Thames Estuary. The project was led by the Ocean and Earth Science, University of Southampton and the Environment Agency, with contributions from the Leibniz Institute for Baltic Sea Research Warnemunde and the National Oceanography Centre. The study contributes to the objectives of UK National Environment Research Council (NERC) project E-Rise: Earliest detection of sea-level rise accelerations to inform lead time to upgrade/replace coastal flood defence infrastructure (NE/P009069/1; I.D.H.).

This dataset contains tabulations of the heights and times of tidal high and low water at St. Helena from 1 October 1826 to 31 October 1827. The tide was recorded by an instrument designed by Manuel Johnson, a future President of the Royal Astronomical Society, while waiting for an observatory to be built. The tabulations in this dataset were obtained by inspection of photographs of Johnson's tabulation sheets that are held in the archive RGO 6/500 in the Royal Greenwich Observatory collection at Cambridge University Library. It is an important record in the history of tidal science, as the only previous measurements at St. Helena had been those made by Nevil Maskelyne in 1761, and there were to be no other systematic measurements until the late 20th century. Johnson’s tide gauge, of a curious but unique design, recorded efficiently the height of every tidal high and low water for at least 13 months, in spite of requiring frequent re-setting. These heights compare very reasonably with a modern tidal synthesis based on present-day tide gauge measurements from the same site. Johnson’s method of timing is unknown, but his calculations of lunar phases suggest that his tidal measurements were recorded in Local Apparent Time. Unfortunately, the recorded times are found to be seriously and variably lagged by many minutes. Johnson’s data have never been fully published, but his manuscripts have been safely archived and are available for inspection at Cambridge University. His data have been converted to computer files as part of this study for the benefit of future researchers. This dataset supports the paper “Cartwright, D.E.; Woodworth, P.L.; Ray, R.D.. 2017 Manuel Johnson's tide record at St. Helena. History of Geo- and Space Sciences”. Richard Ray (National Aeronautics and Space Administration) and Philip Woodworth (National Oceanography Centre) modified and added figures to David E. Cartwright’s original draft paper and sections of text have been updated, but otherwise the paper is as he intended it. This work was undertaken when Philip Woodworth was an Honorary Research Fellow at the National Oceanography Centre in Liverpool in receipt of an Emeritus Fellowship from the Leverhulme Trust. Part of this work was funded by UK Natural Environment Research Council National Capability funding.

The data set comprises time series measurements from offshore pressure gauges mounted on the sea floor. The data holdings are approximately 100 observation months from 30 sites. The data are mainly from trans-ocean sections in the North Atlantic. Data records contain date/time, total pressure (or relative pressure) and, occasionally, temperature. The sampling interval is typically 15 minutes or hourly, over deployment periods ranging from 1 to 6 months. Data were collected mainly by the Proudman Oceanographic Laboratory (POL), now the National Oceanography Centre (NOC) at Liverpool, and are managed by the British Oceanographic Data Centre (BODC).

The Mediterranean-Alpine Experiment (MEDALPEX) data set comprises over 200,000 hourly sea level measurements. Data are included from 28 sites around the northern coast of the Mediterranean and one in the Atlantic at Cadiz. Measurements were collected from December 1981 and September 1982, with a special observing period (SOP) between 15 February and 30 April 1982. Twenty eight coastal sites were instrumented with conventional stilling wells, while one offshore site off Corsica used a bottom pressure recorder. The data are stored, together with benchmark information, as time series at each site with hourly values of sea surface elevation recorded to the nearest millimetre. The aim of the MEDALPEX Experiment was to study the role of atmospheric forcing on the dynamics of the Western Mediterranean. Data were supplied by laboratories in Belgium, France, Monaco, Italy, Spain, UK and former Yugoslavia. Responsibility for assembling, quality controlling and analyzing the sea level data collected during MEDALPEX was vested in the British Oceanographic Data Centre (BODC).

The dataset contains 39148 years of sea level data from 1355 station records, with some stations having alternative versions of the records provided from different sources. GESLA-2 data may be obtained from www.gesla.org. The site also contains the file format description and other information. The text files contain headers with lines of metadata followed by the data itself in a simple column format. All the tide gauge data in GESLA-2 have hourly or more frequent sampling. The basic data from the US National Atmospheric and Oceanic Administration (NOAA) are 6-minute values but for GESLA-2 purposes we instead settled on their readily-available 'verified hourly values'. Most UK records are also hourly values up to the 1990s, and 15-minute values thereafter. Records from some other sources may have different sampling, and records should be inspected individually if sampling considerations are considered critical to an analysis. The GESLA-2 dataset has global coverage and better geographical coverage that the GESLA-1 with stations in new regions (defined by stations in the new dataset located more than 50 km from any station in GESLA-1). For example, major improvements can be seen to have been made for the Mediterranean and Baltic Seas, Japan, New Zealand and the African coastline south of the Equator. The earliest measurements are from Brest, France (04/01/1846) and the latest from Cuxhaven, Germany and Esbjerg, Denmark (01/05/2015). There are 29 years in an average record, although the actual number of years varies from only 1 at short-lived sites, to 167 in the case of Brest, France. Most of the measurements in GESLA-2 were made during the second half of the twentieth century. The most globally-representative analyses of sea level variability with GESLA-2 will be those that focus on the period since about 1970. Historically, delayed-mode data comprised spot values of sea level every hour, obtained from inspection of the ink trace on a tide gauge chart. Nowadays tide gauge data loggers provide data electronically. Data can be either spot values, integrated (averaged) values over specified periods (e.g. 6 minutes), or integrated over a specified period within a longer sampling period (e.g. averaged over 3 minutes every 6 minutes). The construction of this dataset is fundamental to research in sea level variability and also to practical aspects of coastal engineering. One component is concerned with encouraging countries to install tide gauges at locations where none exist, to operate them to internationally agreed standards, and to make the data available to interested users. A second component is concerned with the collection of data from the global set of tide gauges, whether gauges have originated through the GLOSS programme or not, and to make the data available. The records in GESLA-2 will have had some form of quality control undertaken by the data providers. However, the extent to which that control will have been undertaken will inevitably vary between providers and with time. In most cases, no further quality control has been made beyond that already undertaken by the data providers. Although there are many individual contributions, over a quarter of the station-years are provided by the research quality dataset of UHSLC. Contributors include: British Oceanographic Data Centre; University of Hawaii Sea Level Center; Japan Meteorological Agency; US National Oceanic and Atmospheric Administration; Puertos del Estado, Spain; Marine Environmental Data Service, Canada; Instituto Espanol de Oceanografica, Spain; idromare, Italy; Swedish Meteorological and Hydrological Institute; Federal Maritime and Hydrographic Agency, Germany; Finnish Meteorological Institute; Service hydrographique et oc?anographique de la Marine, France; Rijkswaterstaat, Netherlands; Danish Meteorological Institute; Norwegian Hydrographic Service; Icelandic Coastguard Service; Istituto Talassographico di Trieste; Venice Commune, Italy;