United Kingdom Hydrographic Office
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This dataset consists of high resolution tiff photographed images of tide gauge charts, from various historical tide gauges from the Grand Harbour (Port of Valletta), Malta. Due to the historical nature of these records, there is little associated metadata with the original charts. They come from various individual tide gauge locations around the Grand Harbour (Port of Valletta), Malta, and some are labelled with more specific locations, such as French Creek and Ricasoli Breakwater. General coordinates have been given for the geographic coverage: 14.49E to 14.53E, 35.87N to 35.9N. The earliest chart is from the 01/06/1871 and the latest is from 1926. There are gaps of several years in the dataset. In his 1878 paper, On the tides at Malta, G. B. Airy describes the gauge in operation in 1871: "The float was a copper vessel, nearly spherical, about 8 inches in diameter; a vertical rod attached to it passed freely through a guide, and was hinged to the end of a horizontal lever, of which the arms were so proportioned that each space marked on the tabular form between the horizontal lines [one-fourth of an inch. - G.B.A.] corresponded accurately to an inch rise or fall of the float." "The cylinder on which the paper was wrapped revolved once in 24 hours". It is not known how long this gauge was in operation for, but all of the tide gauges that produced the tide gauge charts in this dataset would have been float gauges. The original charts were collected by the Royal Navy as part of their surveying duties of the Grand Harbour. The United Kingdom Hydrographic Office (UKHO) had these charts in its archives, which were difficult to access and in need of conservation. The charts were conserved and photographed and made publically available as digital images to help preserve one of the longest and earliest temporal series of sea level data in the Mediterranean. The original data were collected by the Royal Navy and were placed in the archives of the Admiralty, now the UKHO. The conserved and photographed images were created by the United Kingdom Hydrographic Office Archives for the MALTESER, MediterrAnean Long TErm SEa level Rescue project and then deposited with the British Oceanographic Data Centre. This project was funded under the Central Government Breakthrough Fund, 2014. Reference: Airy, G. B. (1878). On the tides at Malta. Philosophical Transactions of the Royal Society of London, 169, 123-138.
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 underwater noise observations which provide information on noise levels over an 21 year period potentially setting a base line for future environmental monitoring. The data were collected for military operations by RAF Nimrod aircraft using air-deployed sonobuoys. They consist of averaged noise levels, measured in db, at a range of frequencies and depths throughout the UK Exclusive Economic Zone (EEZ).
The UK Argo programme data set comprises measurements of ocean temperature and salinity and provides information of surface and subsurface Lagrangian (measuring movement by tracing the path of a passively drifting object) displacement enabling the derivation of currents. The data set includes a mixture of near-real-time (quality controlled to operational ocean forecasting standards) and delayed mode (quality controlled to climate research standards) data collected by profiling floats. The UK floats from part of a global array throughout the world oceans. Real-time data are available within 24 hours of the float surfacing while delayed mode data become available within 12 months of the profile date. Floats drift at their parking depth (between 1000m and 2025m) for 5 or 10 days depending on float programming. Traditionally floats measured temperature and conductivity at regular intervals during their rise to the surface. In October 2007, the Argo programme achieved its goal to have (and maintain) more than 3000 active floats. As of 2012, some newly deployed floats are being programmed to collect data whilst drifting at their parking depth and during their ascent and additional oceanographic parameters, for example fluorescence, optical backscatter, and dissolved oxygen are being trialled for inclusion in the data set. The data has a variety of uses including assimilation into operational weather forecasts in near-real-time to climate research with the delayed mode data. The data set also includes Argo floats deployed by Mauritius, Saudi Arabia (one float in the Red Sea) Ireland and Portugal, as the British Oceanographic Data Centre manages the data from these floats in addition to those of the UK Argo programme.
The dataset comprises a wide range of physical and biogeochemical oceanographic and atmospheric parameters, plus additional biological measurements and observations. Hydrographic parameters include temperature, salinity, current velocities, fluorescence and attenuance, while biogeochemical and biological analyses of water samples provided measurements of dissolved gases, hydrocarbons, sulphur species, dissolved organic carbon (DOC), halocarbons, nutrients, pigments, bacteria, phytoplankton and zooplankton. Bird identification and cetacean abundance studies were also undertaken, as were tracer release experiments using both inert chemical (sulphur hexafluoride, SF6) and bacterial (Bacillus globigii) tracers. Meteorological data were also collected, including concentrations of various chemicals, supplemented by standard measurements of air temperature, pressure, irradiance, humidity and wind velocities. The data were collected in the North Atlantic Ocean and North Sea between 1996 and 1998, as follows: Eastern Atlantic off the coast of Ireland (June-July 1996 and May 1997); southern North Sea (October-November 1996); and North Eastern Atlantic between the UK and Iceland (June-July 1998). The data were collected during four cruises (RRS Challenger CH127, CH129, CH133 and RRS Discovery D234) using a variety of equipment, including instrumentation deployed at sampling stations (e.g. conductivity-temperature-depth (CTD) profilers) and underway sensors that ran throughout each cruise, yielding continuous measurements of both hydrographic and meteorological parameters. Discrete air and water samplers were also used to measure atmospheric and hydrographic parameters throughout each cruise. The data collection periods were associated with individual ACOSE air-sea exchange experiments: two Eastern Atlantic Experiments (EAE96 and EAE97); ASGAMAGE in the southern North Sea; and the North Atlantic Experiment, NAE. ACSOE was a 5-year UK NERC Thematic Research Programme investigating the chemistry of the lower atmosphere (0 - 12 km) over the oceans. The Marine Aerosol and Gas Exchange (MAGE) study group was the only component of the ACSOE Project that included measurements in the marine environment. ACSOE data management was a shared responsibility between the British Atmospheric Data Centre (BADC) and the British Oceanographic Data Centre (BODC). BODC handled the management of ship data as well as all other data collected in the water column during the ACSOE/MAGE cruises. BODC assisted in the onboard collection and subsequent working up of ship data, and assembled all marine data in BODC's relational database carrying out quality control and data processing as required. ACSOE was led by Prof. Stuart Penkett of the University of East Anglia and cruise principle scientists included representatives of the University of Newcastle Upon Tyne, and the University of East Anglia.