How to Measure the Coastal Currents of Grimsby

1. Where is Skegness?

Skegness is a successful seashore resort in the East Lindsey district of Lincolnshire, England. Skegness stands on the north-eastern frontier of England along the east coastline, literally on the doorstep of the North Sea. This being a prime spot has helped shape its success for it has remained deeply connected to the sea.

The history of the town traces back far enough. Earlier, it was only a small and unheared village. Gradually, it has developed into a popular sea resort. The Skegness architecture is varied. There are some old - style buildings in the town center. They possess simple and classic beauty, with small shops and twisting narrow lanes. There are new developments surrounding the beach area such as large holiday complexes, amusement arcades, and restaurants. They are designed to accommodate thousands of tourists who visit annually. Old - world charm combined with the presence of new facilities makes Skegness highly appealing and unique.

The people of Skegness have a close relationship with the sea. The economy of the town relies on tourism. Its extensive sandy coastline is very popular, attracting families, couples, and lone visitors. Fishing is also important in the town's history. Although the scale of the fishing industry has decreased, there are still some hardworking fishermen who venture out from the small harbour. They bring back such fish as cod, mackerel, and herring. The port is not just a hub for fishing but for excursion boat rides on which holiday-makers and the residents living around Skegness alike get to taste the invigorating sea breeze and experience the coastal scenery surrounding Skegness.

The beaches and coastline around Skegness are crucial to the surrounding ecosystem. The waters off Skegness in the North Sea harbor a vast variety of marine life. Seabirds like cormorants, terns, and seagulls can be seen frequently flying overhead. Seals also sun themselves comfortably on the sandbanks at the beach sometimes. There are numerous species of fish on the ocean floor, and crustaceans like lobsters and crabs. Sandy areas, solitary rock outcrops, and shallow underwater channels exist among the seabed morphology. Not only do these create the region's varied richness but also contribute largely to seawater circulation.

2. What is the state of the coastal currents around Skegness?

The coastal currents around Skegness are influenced by several factors. One of them is tides. The North Sea has two high tides and two low tides every day. The tidal range is variable and accompanying tidal currents have velocities of approximately 1 - 2 knots in some localities, especially at the mouth of minor estuaries or when a particular coastline form exists. At high tide, seawater flows onshore, bringing with it nutrients and sediments from the open sea. This locally enriches the marine environment and brings food and refuge to many marine animals. When the tide is low, the seawater returns and reveals the intertidal zone. The intertidal zone is a rich region, and small crabs, sea anemones, and an assortment of seaweeds are commonly found there.

Wind is also significant. The prevalent south - westerly winds can push the surface seawater toward the shore and make the coastal currents more active. These winds also generate waves that interact with the currents to create a more intricate flow pattern of swirls and eddies. Northerly winds, on the contrary, can push the seawater away from the coast. The gentle curvature of the coastline and small bays compel the currents to converge and diverge in different places. The underwater sandbars and rocky outcrops complicate the current patterns further. They are barriers or pathways, deflecting the course of the water flow and creating still or more disturbed waters. Additionally, the inflow of fresh water from neighboring small streams will impact the pattern of local currents. Fresh water is less dense than sea water, therefore forms a surface layer and flows to the sea, combining with tidal and wind-driven currents.

3. How to track the coastal water flow of Skegness?

Surface Drifting Buoy Technique

Surface drifting buoys are a simple and effective way to track surface-level currents in the area of Skegness. Surface drifting buoys are equipped with GPS or satellite tracking devices. Once they are dropped into the water, they will be pushed by the surface currents. Scientists can track their trajectory over a period of time. From the buoy movement, they can estimate the direction and velocity of seawater on the surface. The method is only applicable to the surface few meters of the water column and not a current depiction of deep-layer seawater because the deep-layer currents are determined by factors such as temperature gradients and salinity contrasts.

Moored Ship Method

In the ship-moored technique, a ship is moored at a particular point offshore of Skegness. Current-measuring equipment such as electromagnetic current meters are employed afterwards. The readings can be recorded over varying depths and provide a accurate vertical profile of direction and velocity of the current. But this method is for one location, and the presence of ships can disrupt natural water flows. The ship's hull and its anchorage can create turbulence in the water that can disrupt the precision of the measurements.

Acoustic Doppler Current Profiler (ADCP) Method

ADCPs have facilitated the measurement of coastal currents off Skegness. It can make measurements of the velocity profile of the entire water column from the water surface to the seabed. ADCPs use sound waves non-intrusively to measure water flow. It emits acoustic pulses and measures the Doppler shift of backscattered signals from suspended sediment in the water, such as sediments, plankton, or small bubbles. By this, the current velocity at different depths can be ascertained and the entire information of the existing structure can be obtained, which is quite relevant for the study of complex coastal current regimes around Skegness.

4. How Do the Doppler-Principle ADCPs Work?

ADCPs work on the Doppler effect principle. The ADCPs send high-frequency pulses of sound into the water. When the sound pulses hit little things in the water, i.e., sediments, plankton, bubbles, etc., they bounce these sound signals to the ADCP. If these small bits are floating down with the current of water, the sound wave that bounces back will differ in frequency from the original sounded wave. That difference in frequency is directly related to how rapidly the small pieces are floating away compared to the ADCP. By measuring this frequency change at different depths of water, the ADCP will calculate how rapidly the water is moving at such depths. The ADCP holds multiple units to calculate the velocity in different directions. This helps in identifying in what direction and with what velocity the water is moving in three-dimensional space.

5. What is Required for Accurate Measurement of Grimsby Coastal Currents?

Material Reliability of Equipment

To accurately gauge the coastal currents off Grimsby, the material of the equipment is critical. The outside of the ADCP must be made of a material that can withstand the harsh North Sea conditions. Titanium alloy is a good choice. It's quite tough, so it can withstand strong sea currents from snapping it, and be able to withstand possible collisions with floating debris and the corrosive salty seawater. It's also slightly stretchy, which decreases the chance of it getting damaged by powerful forces. And the ADCP does not rust quickly either, so the ADCP can be used at sea over an extended time without weakening.

Small Size, Light Weigh, Low Power Consumption, and Low Expense

It is easier to install and work with a light and small ADCP. You can mount it on a small research ship, suspend it over a buoy, or put it on the seafloor. It also disturbs natural water flow as less, hence providing more accurate readings. Using less power is important, especially if it runs on batteries and needs to work on its own for a long time. An ADCP that doesn't cost a lot allows us to use many of them. This is really important for fully understanding the complex coastal current patterns around Grimsby.

6. How to Choose the Right Equipment for Current Measurement?

Based on Usage

• Shipborne ADCP: Best for acquiring current data instantly as a ship sails by near Grimsby. You can use it to study the ocean, see how the water is moving generally in the area, and optimize shipping routes.
• Bottom-mounted ADCP: Ideal for tracking the currents around the seabed over a long period in the same spot. This is highly valuable for measuring how the coastal currents change over the long term, like how climate change affects the surrounding sea environment.
• Buoy-mounted ADCP: Good for monitoring the surface-level currents over a wide area because the buoy rides with the water. It tells us about the way the surface currents change in different places and how the coastal waters exchange with the open North Sea.

Based on Water Depth

• 600kHz ADCP: Suits water that's about 70m deep. It can take very accurate readings in the shallow waters near Grimsby.
• 300kHz ADCP: Suits water that's about 110m deep. It can come in useful in the North Sea near the town where the water is a bit deeper in certain spots.
• 75kHz ADCP: Suitable for use in deep-water areas. While the waters off Grimsby are not usually very deep, it can be employed for study in relation to the deeper - layer currents or for areas where there are deeper channels. It can measure currents as deep as 1000m.

There are some well-known ADCP brands globally, but some are popular, including Teledyne RDI, Nortek, and Sontek. In the event that you want a good product but not very expensive, the ADCP manufacturer China Sonar PandaADCP, with titanium alloy construction, is a great choice. You can find more information at (https://china-sonar.com/).

Here is a table with some well known ADCP instrument brands and models.