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The Changing Face of Ocean Scientific Business
There have been many changes in the workplace over the past 2 decades, not least in the methods off communication and data handling. The ability to handle increasing volumes of data using readily available and affordable technology has revolutionised the way we do business. Some of these technological advances have significantly influenced the instrumentation which we use in marine science but we remain firmly linked to the past in principles of measurement and data quality standards. In this article, I look at the development of marine science and technology business over the past 20 years with particular reference to our experiences in Ocean Scientific International Ltd. (OSIL)
OSIL was founded in April 1989 to take over operation of the IAPSO Standard Seawater Service from the Institute of Oceanographic Sciences (IOS) in Wormley, Surrey. This was a timely decision in terms of business as 1990 heralded the start of the World Ocean Circulation Experiment (WOCE), the largest internationally co-ordinated oceanographic programme ever conducted. WOCE and subsequent programmes (e.g. Argo, CLIVAR) are essential contributors of scientific data to current efforts to relate changes in ocean parameters to climate. During the WOCE programme, ship-based measurements were taken using profiling instruments such as the CTD (Conductivity, Temperature, Depth). Although still widely used, the CTD ‘dip’ provides a vertical transect only at one point spatially and temporally. In more recent years advances in both the reliability of sensors and the data storage/transmission capacity have allowed the remote installation of a range of devices without attachment to a research vessel.
The RAPID programme which started in 2001 installed an array of instrumented moorings across the entire Atlantic Ocean at latitude 26.5°N. The programme aims to improve quantification of the probability and magnitude of future rapid change in climate, with a main (but not exclusive) focus on the role of the Atlantic Ocean's Thermohaline Circulation. Instrumentation included the extensive use of CTD and current meters connected to a data telemetry system via satellite to the shore, giving near real-time datasets.
The broad-scale global array of temperature/salinity profiling floats, known as Argo, has already grown to be a major component of the ocean observing system and CLIVAR is investigating processes and mechanisms that link salinity, the water cycle, ocean circulation, and climate variability. The quality of data from remote sites depends highly on the long-term reliability of the sensor systems utilised. Modern multi-parameter probes offer robust, stable sensors which are easy to maintain and calibrate, thereby providing high quality data for long periods.
The hydrographic measurements made during all of these programmes depend on the use of the IAPSO Standard Seawater (SSW) as a calibration standard to ensure the accuracy and comparability of salinity data. The SSW Service, which originated in Denmark (1901) and now operated by OSIL, still provides the only internationally accepted standard for the calibration of salinity measurements devices. The widespread use of this 
single source standard has ensured the comparability of the millions of salinity measurements made worldwide over the past century: an important factor in the study of long term trends. The currently approved methods for Practical Salinity are based on the measurement of conductivity but, more recently, this has led to some difficulties in density calculations which are used extensively in studies of ocean mixing and circulation. The density of seawater relates to its Absolute Salinity which is, essentially, the total amount of dissolved material in a seawater sample. Some compounds (e.g. silicate) when dissolved have little effect on the conductivity and are therefore missed in the measurement of Practical Salinity. As a first step towards incorporating the difference between Practical Salinity and Absolute Salinity the measurements of Practical Salinity are converted to a defined ‘Reference Salinity’ and then with spatial and silicate data processed to give a best estimate of Absolute Salinity.
As the demand for salinity data increased during the 1990s OSIL expanded its operation to include the sale and support of laboratory salinometers and in situ instruments such as the CTD (conductivity, temperature, depth). One instrument which has proved the test of time has been the Guildline salinometer. The Autosal™, introduced in the late 1970s, offered a significant improvement in accuracy and sample measurement time over the existing inductive salinometers and still leads the field today as the ‘industry standard’ instrument for the high precision measurement of Practical Salinity. Of course, it has developed over the past 20 years with improved electronics and the introduction of a more portable digital version, the Portasal™, but the principle of measurement remains with the 4 electrode conductive cell. OSIL continue to operate, a complete package of instrument supply, technical support and operator training which has proved to be of great benefit to many of the marine scientists and technicians worldwide involved in salinity measurement.
Advances have been made not only in sensor technology but also in data storage/transmission and in power budget management. The use of 
existing communications networks (e.g. GSM) have allowed a cost effective means of monitoring conditions in coastal and near-shore environments. Applications include port and harbour navigation, oil rig safety, pollution control and climate monitoring. One area of significant growth in the past decade or so has been port and harbour development where dredging operations are necessary. Data buoys are used effectively to monitor suspended sediment in the water by the use of turbidity sensors on remote platforms such as buoys. These systems provide effective real-time monitoring for the dredging operation in order to minimise environmental damage and dredger down-time.
Sea-bed studies continue to grow in importance due to the increased demand for minerals and hydrocarbons along with the need for subsea structures such as cables, pipelines and most recently sources of renewable energy. Developments in sonar instrumentation have resulted in highly detailed ‘maps’ of the seabed but the basic methods for actually taking samples have changed very little over the past 20 years. Improved design of corers (e.g. box, gravity, vibro and multiple) have all been developed at OSIL and these continue to be widely used in the collection of sediment samples for chemical, geological and biological studies.
The increasing requirement for renewable energy impacts highly on marine 
resources with developments underway to generate power from waves, tidal streams, tidal range and offshore wind. Marine science and technology plays an important role in scoping suitable sites, assessing environmental impact and monitoring operational conditions. Traditional instrumentation such as current meters, wave sensors and meteorological sensors are widely used on fixed platforms, moorings and data-buoys but more recently the
use of HF radar for coastal monitoring has increased. HF radar can provide measurements of surface currents and waves through analysis of the power spectrum of the radar signal scattered from the sea surface. HF radars are usually located on the coast and can survey beyond 200km from the shore. Their compact design offers a system that can be easily deployed and maintained which will perform even during extreme weather conditions. For example, the SeaSonde HF radar station has one transmitting antenna and one receiving antenna unit which are connected to the radar transmit chassis and receive chassis, controlled by a small desktop computer. The system has a long working life due to its land based location and data can be automatically sent to an office at predetermined intervals or sent directly to the Web for public viewing. Apart from renewable energy, HF radar can also provide valuable data in areas such as pollution management, fisheries, emergency prevention and response.
As reliance on remote installations increases so will the demands on manufacturers of instruments in terms of long term stability, reliability and accuracy. Mathematical models are widely used in predictions of changes locally, in the case of coastal development (e.g. ports and harbours, cables, pipelines) and globally, in the open-ocean (e.g. climate change). The accuracy and ultimate value of these predictions depends on the quality of the data used to develop and test the models. Aquarius, a new satellite monitoring system due to be launched later this year, is designed to provide monthly global maps of salinity variation on the sea surface. However, the satellite data must be verified comprehensively with ‘ground truthing’ from in-situ devices such as moorings, data buoys, autonomous floats and ship-based measurements, to ensure quality.
Marine Science and Technology has grown in importance, on a global scale, in the past two decades. As the world population grows there is an increased demand on resources from the sea such as fisheries, hydrocarbons, minerals and renewable energy. Increased shipping and industry imposes environmental impacts on the sea which require monitoring and control. Probably the largest driver currently for marine science is the study of climate change and its effects. The oceans significantly influence the climate and will also be directly affected by global warming with sea-level rise threatening devastation for many coastal and low-lying regions. The technological changes over the past 2 decades will help to provide more comprehensive datasets for the mathematical models essential for climate prediction. In addition local systems such as tsunami warning devices, sea defence measures and pollution control will all improve as marine technology develops further.
By Paul Ridout, chairman, Ocean Scientific International Ltd, Hampshire, UK
As published in International Ocean Systems July/August 2010.
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