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Waveradar rex at Swanage -
Waverider buoy storage -
Water quality sampling -
Current meter deployment -
Project meteorological station
Oceanographic and Meteorological Survey
EMU Limited's MetOcean team specialises in the provision of high quality meteorological and oceanographic survey and consultancy services encompassing; data collection, processing, interpretation and presentation.
EMU has wealth of experience in using the latest equipment to collect a full range of oceanographic and meteorological data as part of an independent study or in combination with other oceanographic parameters.
Typical Metocean parameters and the equipment used for the collection of the data during a marine survey are described in the following:
Please click on the following titles to navigate to the appropriate section
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WAVES
Wave information is often essential for those needing to know the real time sea state, such as coastal engineers, offshore logistic operations managers, surveyors, fishing vessels, oil rig workers and also leisure craft.
For more information on EMU's recent ground breaking software development in determining real time isolated of wave energy using spectral splitting click here
- Measuring Waves with a Wave Buoy
For long term measuring of wave height and wave direction with telemetred data for real time viewing on a website, EMU use directional waverider buoys. Wave information is often essential for those needing to know the real time sea state, such as survey and fishing vessels, offshore engineers, offshore wind farm logistic managers, oil rig workers and also leisure craft.
Bespoke software written by EMU allows the MetOcean team to monitor the data being received and the position of the buoy at all times. Any indication of the buoy or the data exceeding the anticipated limits of acceptability results in an alert to the MetOcean team 24 hours a day
Data from a deployed buoy is transmitted to a receiving station using HF radio or satellite telemetry. EMU's bespoke software converts the data into user friendly format for publication on a website in near real time. Please see Telemetry for further details
- Channel Coastal Observatory UK Wave buoy network
EMU has set up and maintains a network of over 22 wave buoys around the south coast of the UK for the Channel Coastal Observatory. The network is continually expanding, particularly on the south coast of the UK. The data is freely available to the general public at http://www.channelcoast.org/
Deployment of a wave buoy requires permission to be obtained from the relevant coastal authorities, for which EMU can apply if requested.
- Measuring Waves with a Wave Radar Rex
Measurement of waves and sea level (tides) can be achieved using a Wave Radar Rex or a Etrometa Step Gauge. The downward looking non-contact sensor uses a microwave radar technique to measure distance to the sea surface. Data stored on a remote PC or may be telemetered for display on a website. A Wave Radar Rex is usually installed on a pier, harbour wall or similar structure.
- Measuring Waves - Other Instruments
Waves can also be measured in conjunction the acquisition of current measurements, using an instrument such as an ADCP, AWAC or Aquadopp Profiler. For such measurements these instruments could be fixed to the seabed for short or long term measurements.
- Measuring Tides with a Wave Radar Rex
Measurement of waves and sea level (tides) can be achieved using a Wave Radar Rex. The downward looking non-contact sensor uses a microwave radar technique to measure distance to the sea surface. Data stored on a remote PC or may be telemetered for display on a website. A Wave Radar Rex is usually installed on a pier, harbour wall or similar structure.
Read more about EMU Metocean Real time data Telemetry capability
- Measurements of Tide
A tide gauge can be located on piers and other fixed structures, below the lowest expected water level, to measure the water level of the tide. The data collected is stored within the instrument and can be telemetered to a receiving station for provision of near real time information. A tide gauge is designed to be deployed long term. Tide gauges can also be fixed to a seabed frame.
Measurements of currents can be acquired from instruments fixed on the seabed or vessel mounted. Instruments used for this would be an ADCP, an AWAC or an Aquadopp Profiler. The data collected is stored internally or can be transmitted in real time using telemetry.
Read more about EMU Metocean Real time data Telemetry capability
Seabed deployments require permission to be obtained from the relevant coastal authorities, for which EMU can apply if requested.
- Drogue tracking
Drogue tracking is a method used to help characterise the tidal flow regime of a region. The extent of drogue travel or excursion from the release point is typically measured over both the flood and ebb tide, on both spring and neap tidal ranges. EMU use a unique GPS tracked drogue system, giving a high resolution track.
- Dye Tracing
Dye tracing is a means of establishing the flow of a discharge and the rate of its dilution. This is achieved by releasing a dye into a specified location and tracking its movement over a set area and or set time.
Before dye tracing can be implemented, permission must be sought from the relevant coastal and other water authorities. EMU can apply for this permission if requested
Measurement of Suspended Sediment (Plume Tracking) with Acoustic or Optical Instruments.
Suspended sediment solids can be measured using instruments with acoustic or optical backscatter. An AWAC and ADCP are examples of acoustic back scatter instruments.
There are various types of optical back scatter instruments which EMU use. These can be for example, a YSI Water Quality Sonde, an Idronaut or an Aqualogger. These instruments also measure other parameters.
The YSI Sonde can be fixed to a seabed frame, or it can be attached to a taut line mooring suspended in the water column. It can also be used for transecting and water column profiles.
- Tracer Surveys
Tracers are marker materials, introduced into a system within which movement is occurring, to characterise the displacement taking place. For a tracer to be effective its behaviour must replicate that of the medium it represents, and yet it must be easily distinguishable from its surroundings.
EMU’s UKAS accredited laboratory offers further specialist sediment, water and bacteria tracer capabilities-Read more
EMU has developed a range of tracers, designed for use in investigations relating to:
- Dredging
- Coastal and environmental engineering
- Ports and harbours
- Wastewater treatment
- Trade effluent
- Government regulation
- Environmental consultation
- Environmental tracing
Tracer Applications:
- Validation/calibration of sediment transport models
- Measurement of sediment transport rates
- Identification of sediment transport pathways
- Monitoring of sediment plume behaviour
- Monitoring/evaluation of the impact of engineering works on the environment
- Assessment of the influence of man-made structure on sediment movement
- Linking sediment transport to hydrodynamic mechanisms
- Outfall dispersion and dilution studies
- Point and diffuse source pollution studies
- Pipe leakage investigations
- Wastewater treatment process studies
EMU can provide measurement of a variety of meteorological parameters using a meteorological station as part of an independent study or in combination with other oceanographic parameters.
EMU provides meteorological stations that can have a variety of sensors to measure:
- Wind speed, gust and direction
- Air temperature
- Barometric pressure
- Solar radiation
- Rainfall
The meteorological station can be installed for a short period (one month) or long term. It can be installed to support other data being acquired simultaneously. The Meteorological station is usually attached to the side of a building or its own structure. The data collected from the sensors are logged within the instrument and are retrieved at regular service intervals. Alternatively the data can be telemetered for real time display on a website.
Read more about EMU Metocean Real time data Telemetry capability
Channel Coastal Observatory Met data
As part of the Channel Coastal Observatory network of wave, tide and meteorological data collection and dissemination, EMU have installed meteorological stations at Deal Pier, Sandown Pier, Swanage Pier and West Bay Pier. Data from these is freely available to the public at www.channelcoast.org/
EMU can undertake sampling for microbiological, nutrient and physicochemical analyses at our UKAS accredited laboratories
- Recordings of in-situ PAR, salinity, temperature and dissolved oxygen
- Interpretation and presentation of results
- Microbial tracers – Bacillus globigii, Serratia marcescens
- Particle tracers - fluorescent microspheres
- Fluorescent Tracers – Rhodamine WT
- Data mapping
- Coastal, surface and depth sampling
Read more about EMU’s water quality capability and other specialist laboratory services