A tanker full of chilled natural gas is about to complete a trip through the Arctic Ocean to Asia, as a combination of climate change, the shale-gas revolution and the earthquake in Japan opens a potentially disruptive trade route.

The tanker Ob River is scheduled to deliver a cargo of Norwegian gas to energy-starved Japan on Tuesday after traveling from Norway through the Arctic above Russia. The trip takes three weeks less than it would if the gas took its normal route though the Mediterranean Sea, the Suez Canal and around Asia.

Three disparate events made the trip feasible and profitable. Climate change has meant ships can pass through the Arctic during the summer. A flood of U.S. shale gas helped push down prices in Europe, and higher demand in Asia, in part due to the Japanese earthquake, has made chilling and liquefying European gas for shipment to Asia economic.

Higher insurance expenses and the cost of an icebreaker to accompany the tanker are offset by the fact that a shorter voyage means a shorter lease period for the tanker.

Gazprom Marketing and Trading Ltd., a unit of Russian gas firm OAO Gazprom , is behind the project to send an initial cargo of deep-chilled liquefied natural gas from Norway's Hammerfest Snohvit LNG project to Japanese utility Kyushu Electric Power Co. Inc. Gas must be chilled under pressure to convert it into a liquid so that it can be shipped by tanker.