The divesites in Maldives are broadly divided in: Thilas, a mountain underwater; Kandus, a corridor or passage in the atoll; and the reefs inside the lagoons. The Kandus and the Thilas are commonly affected by strong currents, while the reefs inside the lagoons are protected areas.
The currents in the Maldives are famous and infamous for its strength. An obvious solution to avoiding the currents would be to dive during change of tides. But it is even possible that during change of tides the currents are stronger than during the previous low or high tide currents. Because of a complex interplay of the prevailing monsoon winds, ocean currents and the tidal currents, currents can vary strongly in time and place.
The ocean currents come from the same direction as the currently prevailing monsoon winds, from the southwest in the period from mid-May through mid-November and from the northeast during mid-November to mid-May. In addition, there is the influence of the tides: during full and new moon, a large tidal difference takes place, which means stronger currents. In between full and new moon the currents are less fierce. The result of these ocean currents and tidal currents determine the prevailing currents. They can work against each other to prevent any flow while almost 6 hours later (when the tide turns) they can work together which results in very strong currents (flow rates of 4 knots are measured).
During the southwest monsoon most plankton will gather on the east side of the atolls (where all the organic material flushes out of the atolls ) and you will see beautiful clear ocean water on the west side of the atolls. During the northeast monsoon this will be the other way around. The location of the large filter feeders (mantas and whale sharks) is mainly determined by the location of plankton.
Because the currents can be strong a surface marker buoy is required by all dive centers in Maldives. This is a surface buoy a diver can send to the surface during his or her safety stop so the crew of the dhoni (the local diving boats) can see where the divers are located so they can pick them up. Gloves are (in contrast to many other locations) strongly recommended. These are used to hold on to rocks (not coral!) when experiencing strong currents. A dive computer is manditory, it's widely agreed to dive up to 30m, and maximum divetime is 1 hour for safety (strong currents) and dive planning.
Commonly known as the "Pearls of the Indian Ocean" the Maldives lie on the equator southwest of Sri Lanka. The archipelago stretches over 800km from north to south and over 100km from east to west. Only 200 of these islands are inhabited and nearly a half of these have been developed as exclusive resorts.
The islands of the Maldives are part of 26 natural coral atolls. The word 'atoll' is originally a Maldivian word which found its way into other languages. The atolls are underwater platforms lying on a ridge in the Indian Ocean. The edges of these platforms are higher and form a large protective ringrif with occasional openings. In the atolls islands are often surrounded by lagoons and have their own protective reefs and lagunes.
The Maldives is listed in the Guinness Book of Records as being the flattest country in the world. The highest point is less than 3 meters above sea level and the average of the islands is less than 2 meters above sea level.
Because the Maldives is at the equator, the climate is determined by the trade winds. From mid-November to mid May, the wind blows from the northeast and relative dry air from India is transported. From mid-May to mid-November, the wind blows from the southwest and then relative moist air is transported from the Indian Ocean. Especially the transition from dry to wet season (May), is accompanied by strong winds and tropical storms. The transition from dry to wet season is generally much more gradual and calm. Late November untill late March is high season in the Maldives with calm weather and lots of sunshine. In recent years, however, global climate change also changed the weather in the Maldives so seasons are not as clear as they used to be.
Diving in the Maldives can only be described as simply spectacular, there are hundreds of dive sites scattered throughout the islands and plenty of good house reefs, many of which are considered world class. A lot of the diving is concentrated around diving North Male Atoll and diving North Ari Atoll, however there are many places further afield for the more adventurous divers.