ABOARD XUELONG, March 28 -- Chinese icebreaker Xuelong, or Snow Dragon, continued Friday its search for the missing Malaysia Airlines jet MH370, heading north to a new search area in the southern Indian Ocean designated by the Australian authorities.

The new area, at 319,000 square km, is about four times bigger than the previous search area in the same ocean and lies 1,100 km to the northeast, according to the Australian Maritime Safety Bureau.

MH370, a Boeing 777-200 with 239 people on board, vanished from radar screens in the early hours of March 8 while on a scheduled route from Kuala Lumpur to Beijing.

The search has entered the third week but the plane's whereabouts remain unknown. Australian search and rescue authorities announced Friday they had relocated the search area after receiving its most credible lead to date.

The Chinese icebreaker is scheduled to arrive in the center of the new search area in the early hours of Sunday and meet Chinese Maritime Safety Administration patrol ship Haixun 01 there, said Liu Shunlin, commander in chief of Xuelong's search efforts.

During its voyage to the waters, crew and researchers aboard Xuelong will also enhance observation, Liu said.

A Xinhua reporter aboard Xuelong observed Friday the weather in the southern Indian Ocean has become better, overcast and sometimes sunny.

Although the visibility reached 10 to 15 km and the wind weakened to a fresh to strong breeze, there was a heavy swell of 3.5 to 4.5 meters, which made the ship swing at an amplitude of up to 15 degrees.

On the icebreaker, an echo sounder indicating the depth of water showed the maximum depth reached was 5,701 meters. An acoustic Doppler current profiler was measuring the flow velocity and direction of the ocean currents.

Researchers modified their equipment, such as hooks, fishing nets and buoys, to salvage floating objects. They also drew a picture of the flow field of surface waters in the southern Indian Ocean to give references for the search.

"The marine environment is very harsh. The pressure of the water will grow by 0.1 megapascal, if the depth of the water increases by 10 meters," said Jiao Yutian, head of the Chinese research team.

"A floating wood block will sink when the water depth reaches 1,000 meters and an iron box will be flattened when it submerges to thousands of meters deep," he added.

However, Jiao said Chinese researchers have successfully salvaged floating or submersible buoys during several scientific expeditions to the Antarctic before. "Once we find suspicious floating pieces, we will manage to salvage them."

The icebreaker was on its way back home from its 30th Antarctic expedition, but changed course to help search for the missing aircraft.