About 450 icebergs up from 37 a week earlier have floated into water where Titanic sank, forcing tanks to divert and creating global warming fears

More than 400 icebergs have floated into the North Atlantic shipping lanes over the past week in an remarkably large-scale swarm for this early in the season, forcing tanks to slow to a creep or take detours of hundreds of kilometres.

Experts are attributing it to uncommonly strong counter-clockwise winds that are drawing the icebergs south, and perhaps also global warming, which is accelerating the process by which chunks of the Greenland ice sheet break off and swim away.

As of Monday, there were about 450 icebergs near the Grand Banks of Newfoundland, up from 37 a week earlier, according to the US Coast Guards international ice patrol in New London, Connecticut. Those kinds of numbers are typically not understood until late May or early June. The average for this time of year is about 80.

In the water close to where the Titanic went down in 1912, the icebergs are forcing ships to take precautions.

Instead of cutting straight across the ocean, trans-Atlantic tanks are taking detours that can add around 650 km( 400 miles) to the trip-up. Thats a period and a half of added travel day for many large-scale cargo ships.

Close to the Newfoundland coast, cargo ships owned by Oceanex are throttling lane back to three or four knots as they make their lane to their home port in St Johns, which can add up to a period to the trip-up, told executive chairperson Captain Sid Hynes.

One ship was drawn out of service for mends after hitting a chunk of ice, he told.

It builds everything more expensive, Hynes told. Youre burning more ga, its taking a longer time, and its hard on the equipment. He called it a very unusual year.

US Coast Guard Commander Gabrielle McGrath, who results the ice patrol, said she had never seen such a drastic increased number of such a short time. Adding to the peril, three icebergs were discovered outside the boundaries of the region the Coast Guard had advised mariners to avoid, she said.

McGrath is predicting a fourth consecutive extreme ice season with more than 600 icebergs in the shipping lanes.

Most icebergs entering the North Atlantic have calved off the Greenland ice sheet. Michael Mann, administrator of the earth system science center at Pennsylvania State University, said it was possible climate change was to move to more icebergs in the shipping lanes, but wind patterns were also important.

In 2014, there were 1,546 icebergs in the shipping lanes the sixth most severe season on record since 1900, according to the patrol. There were 1,165 icebergs in 2015 and 687 in 2016.

The international ice patrol was formed after the sink of the Titanic to monitor iceberg peril in the North Atlantic and warn ships. It conducts reconnaissance flights that are used to produce charts.

In 104 years , no ship that has heeded the advises has struck an iceberg, according to the ice patrol.

Read more: https :// www.theguardian.com/ environment/ 2017/ apr/ 06/ huge-fleet-icebergs-north-atlantic-shipping-lanes