KUP 11: Ability to apply the meteorological information available

Learning objective:

The objective of this KUP is to develop the ability to apply the meteorological informaon on board, which includes interpreting meteorological data, applying meteorological information, maintaining safe navigational watch.

Learning content:

Under the International Convention on Standards of Training, Certification, and Watchkeeping for Seafarers (STCW), a seafarer’s competence in applying meteorological information involves:

Interpreting Meteorological Data: Seafarers must be able to correctly interpret various meteorological information, such as weather reports, forecasts, and data from instruments. More details refer to the “Guide to marine meteorological service”¹.

2. Applying Meteorological Information

They must use this information to make informed decisions that ensure safe navigation and operation of the vessel. This includes predicting weather conditions and understanding their potential impact on the vessel’s route and safety.

Weather can be challenging to predict, especially on waterways, but good forecasting can help ships and their crews navigate and make decisions that reduce risks. Bad weather can cause vessels to capsize, run aground, or collide with other ships or objects. Maritime weather forecasting is extremely important in making maritime jobs safer. Weather at sea is not the same as weather over land. The main driving forces are winds, including the trade winds, which blow to the west in the tropical oceans, and the westerlies, which blow to the east in the mid-latitude regions. Winds create surface ocean currents by dragging across the water. In the northern hemisphere, these currents move in clockwise rotations, while in the southern hemisphere, they move in counterclockwise rotations. Smaller currents also move along the edges of the major currents, called gyres. The smaller boundary currents are numerous and include the Gulf Stream, which moves from the Gulf of Mexico along the eastern coast of the U.S. and Canada and across the ocean to the British Isles. These currents generate and influence much of the maritime weather that we see across the world’s oceans. Weather generates waves and swells, which have a significant impact on vessels at sea. Winds produce waves in the oceans, and the size of the waves depends on the strength and duration of the winds and how far the winds blow without interruption. Swells are groups of large waves that outrun the wind or storm that generated them. Ships at sea may also face rogue, huge waves among smaller waves. These can cause a lot of damage. Waves and winds occurring together during storms are particularly dangerous, including hurricanes, typhoons, and cyclones. These are huge and damaging storms. They consist of high-speed winds rotating around a calm center called an eye. Predicting a hurricane’s formation, strength, duration, and path is integral to maritime forecasting ².

Weather Forecasting Methods
1) Weather Satellites
Satellites are essential for tracking weather across oceans and other bodies of water. Meteorological satellites are dedicated to monitoring weather and include those that orbit at the poles of the Earth, stationary satellites that monitor just one part of Earth’s surface, and satellites that orbit the entire planet. Satellites can gather information about clouds, the temperature of the air and water, currents, dust storms, ice coverage, and more.

2) Weather Buoys
Weather buoys and weather ships are floating weather stations that monitor maritime conditions. A moored buoy is a stationary device that can be tethered to one part of the ocean to collect weather information. There are also drifting buoys that track weather as they move across oceans. There are currently more than 1,000 drifting weather buoys worldwide, helping to forecast marine weather.

3) Computer Modeling
Information taken from these weather stations and satellites is used by meteorologists and computer software to model currents and winds, track temperatures and storms, and predict what weather will happen next, where it will happen, and how it may impact ships and other vessels on the oceans.

3. Maintaining Safe Navigational Watch

The application of meteorological information is critical in maintaining a safe navigational watch, adjusting the ship’s course, speed, and actions as necessary to avoid hazardous weather conditions.

Reference:

1. Guide to marine meteorological service. https://etrp.wmo.int/pluginfile.php/20255/mod_resource/content/3/WMO-No.471_en.pdf

2. Navigation. Ding Yong. Publisher: People’s Communications Press.