woda: Tide

Evidence: 100 • authority: 72

Tides are the periodic rise and fall of sea level resulting from the differential gravitational forces exerted primarily by the Moon and the Sun, combined with inertial effects associated with the Earth–Moon system’s orbital motion and the Earth's rotation. While these astronomical forcings generate the fundamental tidal potential, actual observed tides are strongly modified by terrestrial factors, including the geometry of ocean basins, continental boundaries, bathymetry, the coriolis effect, frictional dissipation within shallow seas and the tidal resonance of coastlines. Tides vary on timescales ranging from hours to years due to a number of factors, which determine the lunitidal interva…

Evidence: 55 • authority: 88

Reconstructing sparse sea-level records: nearby tide gauges and satellite altimetry outperform station-only deep learning over 31 years in the East China Sea. Offshore sea-level records are essential for monitoring coastal and shelf-scale ocean variability, yet they are frequently disrupted by instrumental and operational gaps. Here we reconstruct monthly sea level for the Ieodo Ocean Research Station, an offshore platform in the East China Sea, over 1993–2023, and use it to ask how far a sparse single-station record can be extended by data-driven methods. Observations were corrected for the inverse barometer effect and screened for outliers and completeness. Two families of gap-filling app…

Evidence: 55 • authority: 80

Filling gaps and extending inland tide gauge records for accurate long-term and extreme water level analysis

Evidence: 55 • authority: 88

Reprocessed height time series of GPS stations at tide gauges. Abstract. Precise weekly positions of 403 Global Positioning System (GPS) stations located worldwide are obtained by reprocessing GPS data of these stations at the time span from 4 January 1998 until 29 December 2007. The used processing algorithm and models as well as the solution and results obtained are presented. Vertical velocities of GPS stations having tracking history longer than 2.5 yr are computed and compared with the estimates from the colocated tide gauges and other GPS solutions. Examples of typical behavior of station height changes are given and interpreted. The derived time series and vertical motions of continu…

Evidence: 48 • authority: 92

Estimating tidal constituents in shallow waters from satellite altimetry using a 2D hydrodynamic model with nonlinear tide-surge interactions.. Tidal models that incorporate satellite altimeter data have historically shown discrepancies in accuracy between shallow and deep marine environments. A recent study suggests that these differences may partly stem from neglecting the nonlinear tide-surge interactions in tidal analyses. In this study, we introduce a novel method for estimating tidal constituents from satellite altimeter data in shallow waters, leveraging a 2D hydrodynamic model that accounts for these nonlinear interactions. This approach substantially reduces the variance of unaccou…

Evidence: 48 • authority: 72

A harmful algal bloom (HAB), or excessive algae growth, sometimes called a red tide in marine environments, is an algal bloom that causes negative impacts to other organisms by production of natural algae-produced toxins, water deoxygenation, mechanical damage to other organisms, or by other means. HABs are sometimes defined as only those algal blooms that produce toxins, and sometimes as any algal bloom that can result in severely lower oxygen levels in natural waters, killing organisms in marine or fresh waters. Blooms can last from a few days to many months. After the bloom dies, the microbes that decompose the dead algae use up more of the oxygen, generating a "dead zone" which can caus…

Evidence: 41 • authority: 92

ArcTiCA: Arctic tidal constituents atlas.. Tides in the Arctic Ocean affect ocean circulation and mixing, and sea ice dynamics and thermodynamics. However, there is a limited network of available in situ tidal coefficient data for understanding tidal variability in the Arctic Ocean; e.g., the global TICON-3 database contains only 111 sites above 60°N and 21 above 70°N. At the same time, the presence of sea ice and latitude limits of satellite altimetry complicate altimetry-based retrievals of Arctic tidal coefficients. This leads to a reliance on ocean tide models whose accuracy depend on having sufficient in situ data for validation and assimilation. Here, we present a comprehensive new da…

Evidence: 41 • authority: 92

Sea level trends along the South African coast from 1993 to 2022 using XTRACK altimetry, tide gauges, and GNSS measurements.. This study presents a comprehensive investigation of the complex dynamics of sea-level rise (SLR) and its multiple impacts on coastal regions in southern Africa. We meticulously analyse trends and patterns in SLR and subsidence rates using a wealth of data from 1993 to 2022, including observations from a network of 10 reliable tide gauges and XTRACK data processed using the Coastal Altimetry Approach to minimise the shortcomings of conventional coastal altimetry data. Our results show that sea level rise in coastal areas of South Africa, such as Cape Town (6.3 mm/yr)…

Evidence: 41 • authority: 80

Previous Studies of Relative Sea Level from Tide Gauges

Evidence: 41 • authority: 92

RTEDAP framework for real-time event-driven data aggregation and processing in tsunami early warning systems.. Tsunami early warning systems are critical for minimizing the impact of seismic events on coastal communities. However, existing systems face challenges in terms of latency, scalability, and real-time data processing. This research introduces RT-EDAP (Real-Time Event-Driven Data Aggregation and Processing), a novel framework designed to address these issues by enhancing the efficiency of tsunami prediction and alert dissemination. The primary objective of this study is to develop a robust, low-latency, and scalable TEWS that can effectively handle multi-source data streams and deli…

Evidence: — • authority: 80

Artificial Neural Network-Based Data Recovery System for the Time Series of Tide Stations

Evidence: — • authority: 80

Factors Governing the Cooling of Water in Boiler Water Level Gauges