How to measure the coastal currents of Kuwait?

1. Where is Kuwait?

Kuwait is a small, yet prosperous country, lying at the northern end of the Persian Gulf. Its northern boundary consists of Iraq, while the southern border is Saudi Arabia. Kuwait is renowned for its gigantic oil resources and strategic position within the world energy market.

Kuwait is primarily characterized by flat and arid landscape, with an extended coastline running on the Persian Gulf. The coastal areas include beautiful sandy beaches that are a source of enchantment for the locals as well as the visitors. Its capital, Kuwait City, is a modern town with ultra-modern architecture and a busy port facility.

Most waters around Kuwait in the Persian Gulf are shallow and warm for the most part of the year. The gulf is a well-endowed marine environment inhabited by many types of fish, crustaceans, and other sea creatures. The gulf also has a primary shipping lane on which oil tankers and vessels of many types move up and down carrying the oil and other products to and from the various terminals along its coastline.

2. What is the condition of the coastal currents around Kuwait?

A variety of factors drives coastal currents off Kuwait. Of these, tidal currents exert the greatest influence. Throughout the Persian Gulf, a combination of gravitational tugs from the moon and sun creates regular fluctuations in sea level along the Kuwait coastline. However, these kinds of tidal currents can vary between being very weak or even strong depending on the phases of the moon and where specifically it is in the path of bathymetry.

Equally important is the contribution by the wind-driven currents, The prevailing winds around the region can also displace the surface waters, thereby creating surface currents. In fact, regional seasonal winds - like Shamal winds from northwest contribute to a strong drive coastal circulation. These, in turn may create stronger surface currents and even result in the modification of the mixing of water masses.

The underwater topography around Kuwait also influences currents: underwater ridges, channels, and shoals can deflect and alter the course of water. Shallow areas may slow down the currents, while deeper channels can accelerate them, contributing to a complex and dynamic current regime.

3. How to observe the coastal water flow of Kuwait?

Surface Drift Buoy Method: This method makes use of buoys deployed on the water surface, which are allowed to drift with the currents. Large buoys are normally fitted with GPS or other tracking devices. By monitoring the movement of the buoys over time, the direction and speed of the surface currents can be determined. However, this method mainly provides information about the surface layer and may not give a detailed understanding of the vertical structure of the currents.

The Anchor Ahip Method: It is based on anchoring a ship in a fixed position within a reasonable distance from the coast of Kuwait. On the ship, instruments are installed to measure the flow of water around the ship, such as current meters. This approach will give quite accurate results near the ship but cannot accommodate a large area and variations in depth at the same time.

ADCP Method: This is the more modern and efficient means of measurement for coastal currents. In ADCP current meter, the principle of the Doppler effect is utilized in measuring the water's velocity at different levels within the column of water. ADCP current profiler emits acoustic pulses into the water and measures the frequency shift of the reflected signals from moving water particles. This will help understand the vertical profile of the currents right from the surface to the seabed.

4. How Do ADCPs Based on the Doppler Principle Work?

ADCPs work according to the Doppler principle. In general, they use transducers to transmit acoustic pulses into the water. As the produced sound waves meet moving particles of water, their reflective waves change frequency because of the Doppler effect. It should be mentioned that the shifting frequency is proportional to the velocity of water particles in relation to the ADCP meter.

Usually, ADCPs have more than one transducer in order to measure water velocities in different directions. The ADCP flow meter can thus calculate the three-dimensional velocity in water-that is, east-west, north-south, and vertical directions-emitted by pulses in different directions and the frequency shifts of the reflected signals. It also measures the time it takes to travel by the sound waves from the transducer toward the water particles and back again. By knowing the frequency shift, with this information, there will be an accurate delineation of the speed and direction of water flow at depth.

5. What is needed for high-quality measurements of Kuwait coastal currents?

The equipment to be used in the measurement of coastal currents around Kuwait should have certain characteristics to ensure high-quality measurement. The materials used for the equipment should be of a reliable nature and capable of withstanding the harsh marine environment. The device should be small in size and lightweight, which will enable its deployment and handling easily. Low power consumption is also vital for such devices to ensure their operational continuity, especially for long-term monitoring.

The ADCP meter casing is preferably to be made of Titanium Alloy. For such an environment as the Persian Gulf-saline, it needs to have excellent corrosion-resistant properties. Besides, it has a high strength-to-weight ratio, thus giving durability while keeping the equipment relatively light. Material that can withstand the pressure changes for different water depths.

6. Selection of Equipment for Current Measurement

Selection of Equipment for Current Measurement in Kuwait

Depending on the purpose of usage, various types of ADCPs can be selected. For example, a ship-borne ADCP installed on a vessel is capable of measuring currents while the ship is in motion. This is useful in covering a wide area of the coastal waters. A bottom-mounted ADCP, which is fixed to the seabed, measures the currents passing above it with steadiness. It is very good for monitoring over a long period at a given location. The buoy-mounted ADCP combines advantages of mobility with ease of deployment, and one can take measurements over different areas.

The Frequency of ADCP

The frequency of ADCP depends on the water depth. For water depths up to 70m, one can use a 600kHz ADCP as it returns highly resolved data in shallow waters. For depths of up to 110m, the best would be a 300kHz ADCP. If the waters are deeper, like near 1000m, a 75kHz ADCP should be employed to ensure the measurement is accurate over a large vertical range.

There are well-known ADCP brands such as Teledyne RDI, Nortek, and Sontek. However, for a cost-effective option with good quality, the China Sonar PandaADCP is worth considering. It is made of all-titanium alloy material and offers an excellent cost-performance ratio. You can find more information on its website: https://china-sonar.com/.

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