Alister Doyle / Reuters
Hans Lindberg, a 56-year-old Swede, points toward an area of reeds that has risen from the Baltic Sea, forming a land bridge to what used to be an island where he spent his summers as a child in the early 1960s.
LULEA, Sweden -- A Stone Age camp that used to be by the shore is now 125 miles from the Baltic Sea. Sheep graze on what was the seabed in the 15th century. And Sweden's port of Lulea risks getting too shallow for ships.
In contrast to worries from the Maldives to Manhattan of storm surges and higher ocean levels caused by climate change, the entire northern part of the Nordic region is rising and, as a result, the Baltic Sea is receding.
"In a way we're lucky," said Lena Bengten, environmental strategist at the Lulea Municipality in Sweden, pointing to damage from superstorm Sandy that killed more than 200 people from Haiti to the United States.
The uplift of almost 0.4 inches a year, one of the highest rates in the world, is part of a continuing geological rebound since the end of the Ice Age removed a vast ice sheet from regions around the Arctic Circle.
"It's a bit like a foam-rubber mattress. It takes a while to return to normal after you get up," said Martin Vermeer, a professor of geodesy at Aalto University in Finland. Finland gains 2.7 sq miles a year as the land rises.
In the Lulea region just south of the Arctic Circle, mostly flat with pine forests and where the sea freezes in winter, tracts of land have emerged, leaving some Stone Age, Viking and medieval sites inland.
That puts human settlements gradually out of harm's way from sea flooding, unlike low-lying islands from Tuvalu to Kiribati or cities from New York to Shanghai. Facebook is investing in a new data center in Lulea on land that was once on the seabed.
A recent study published in the journal 'Nature' suggests the U.S. may experience a 5 ft. rise in sea level given all of the fossil fuel that has already been burned. NBC's Anne Thompson reports.
But rising land also means costs. Lulea is planning to deepen its port by 2020 to let in bigger ships and offset land rise at a cost of 1.6 billion Swedish crowns ($237.86 million).
"Even if we didn't have the ambition to have larger ships we would still have to do it on a smaller scale just to compensate for the land rise," said Roger Danell, head of the port.
Alister Doyle / Reuters
A view of the Swedish Baltic Sea port of Lulea Nov. 14, 2012.
Dredging just for existing ships would cost $60.46 million as the water gets shallower at the port that was last deepened in the 1970s, construction manager Jeanette Lestander said. Main exports are iron ore and the main import is coal.
But a projected rise in sea levels due to global warming means dredging to offset land rise for the next 40 years will be slightly less than in the 1970s.
"The rate of sea-level fall will be slowing," Lestander said during a visit to the port. The future sea fall is estimated at 0.28 inches a year from 0.35 inches.
In the north of Sweden, 125 miles inland and 558 feet above current sea level, archaeologists recently found a 10,700 year-old Stone Age hunters' camp near Pajala that was originally by the Ancylus Lake, the forerunner of the Baltic Sea.
"We carbon-dated burnt bones from a fireplace," archaeologist Olof Ostlund at the Norrbottens museum said. The hunters would have been near the retreating ice sheet that was once 1.9 miles thick.
In the past century, as the climate has warmed, sea level rise has accelerated. Scientists predict it will only increase, and they're studying changes in the ocean and land to better understand how and why the water is rising. NBC's Anne Thompson reports for "Changing Planet," produced by NBC Learn in partnership with the National Science Foundation.
Experts examined sediments that showed the camp was on the shore of the former giant lake, briefly isolated from the North Sea by land uplift in the south before breaking through again.
Lulea's old town, with a 15th century church and bright red-painted wooden houses, was originally built on an island for safety when it was as an outpost of the then Swedish-Finnish Kingdom to counter Russian influence near the Arctic Circle.
Now the village is high and dry, out of sight of the sea. Sheep graze on a field in what used to be the port. In one spot, Sweden's coastline has risen about 984 feet since the Ice Age ended about 10,000 years ago.
Water receding after Biblical flood?
The falling water level puzzled people for generations. Some Christians believed it was caused by still-receding waters after the Biblical story of Noah who built an Ark to rescue the world's animals from a God-sent flood.
Elsewhere in the world, many nations are worried by potential costs if sea levels rise in line with scenarios by the U.N. panel of climate scientists for a gain of 7-24 inches this century after 6.7 inches in the last century.
The panel says that rising temperatures, caused by emissions of carbon dioxide from burning fossil fuels, are the cause.
The U.N. projection excludes the possibility of an acceleration of the melt of Greenland and Antarctica, because that is uncertain.
Even so, many experts expect a quickening thaw and say that sea levels could rise in total by 3.3 feet this century.
Experts say human-produced carbon dioxide is playing a big role in the warming of the atmosphere, which is having a major effect on the world's oceans. Warmer oceans results in rising sea levels and more powerful hurricanes – but reversing the effects of global warming could take decades. NBC's Robert Bazell reports.
Near Lulea, local resident Hans Lindberg, 56, looks out of the wooden seaside cabin that his parents built in 1960 toward what was then the island of Kalkholmen a few hundred yards away.
"We could look out from here and only see the sea," he said, pointing to a muddy bank where reeds are growing and linking the island to the mainland. Residents of the former island say they fear the link may bring unwanted visitors -- perhaps burglars.
Alister Doyle / Reuters
Lindberg shows a family photo from the early 1960s of two girls playing in a sandpit that used to be at his parents' summer cottage near Lulea.
"You can walk to the island now. When I was young my father had a heavy boat that we could pull through the shallow part of the channel. That's now impossible," he said.
As evidence of the change, he shows a faded album with a black and white photo of two young girls -- his sister and cousin -- playing in a sandpit in the 1960s by the cabin. It shows an open sea with no sign of the muddy causeway.
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