News

Barrow under siege

 

screen-shot-2016-09-14-at-4-03-34-pmThe apocalypse is at the door of Alaska’s and America’s northernmost community. You can read about it on the internets.

“A stroll along one of Barrow’s handful of roads shows just how tenuous civilization’s perch is,” writes Adam Popescu of The Washington Post. “Bulldozed mounds of sand and soil more than 20 feet high are all around town. But these sea walls are frequently penetrated as swells and storms overtop the walls, sometimes sending houses, built on stilts because of the impenetrability of permafrost, floating inland for miles.”

Houses “floating inland for miles?” How exactly does that work? Are the houses in Barrow somehow different from the houses in the rest of the country that end up inundated by floods.

Do Barrow houses get up on their stilts and move crab-like across the tundra at high water, or are they like jack-up oil rigs? The houses are built to float and the owners only put the stilts down when they want to stop floating.

Jack-up houses would seem a natural for Alaska given all the fears about global warming and the rise of the oceans. If high water threatens your community, just prepare the house to set sail, ride away on the rising sea, and jack the house up wherever it stops.

Unfortunately, no one contacted in Barrow seems to know anything about houses that floated away or houses “built on stilts,” although several Barrow residents did note there are a lot of buildings built on “pilings.”

A couple of people suggested a review of websites that feature Arctic construction.

There you will find that houses are not “built on stilts because of the impenetrability of permafrost” but built on pilings driven deep into the permafrost. The pilings for the new Public Heath Service Hospital in Nome, for instance, were “drilled 30 feet through permafrost and set in the bedrock,” according to an article in the 2007 “Alaska Contractor” magazine.

Arctic construction

Pilings are driven or drilled into the permafrost to varying depths all across the Arctic these days. The practice appears to have started slightly before Alaska Statehood.

“There was no known widespread use of pile foundations in Arctic and subArctic Alaska prior to 1950,” according to a 1957 report written for the U.S. Army Corps of Engineers. The military in Alaska began experimenting with wood, precast concrete, iron and other pilings in the early 1950s.

Steam-thawed holes allowed for the placement of piles up to 16 feet deep, according to the report, which said that “driven piles consisted of 8-inch diameter, open-end, standard-weight steel pipe driven to embedments (sic) ranging from 4 to 16 feet in permafrost.”

Water drilling, churn drilling, and power augering were all tried to create holes in permafrost (frozen ground) to allow piling placement.

“The pile driving experience at the Research Area demonstrated that driving of steel pipe piles into permafrost is a practical and economical method,” the report concluded. On average, it took about 5 minutes to drive a piling 8 feet deep into the Washington Post’s “impenetrable permafrost.”

It took about 4 minutes more to reach 16-feet.

Structures built atop pilings started to become an Arctic norm not long after these experiments. The Department of the Army in 1983 published a 269-page guide for building atop pilings. The manual called for buildings to be attached to the piles so that they would stay on the piles.

But things are apparently different in these the days of climate change when “warming air, melting permafrost and rising sea levels are threatening” to place Barrow residents “among the world’s first climate-change refuges.”

“…Researchers predict that by mid-century, the homes, schools and land around Barrow and its eight surrounding villages will be underwater,” the Post story says.

Sea levels could to rise 2 to 2.5 feet at most by 2050, according to the U.S. Global Change Research Program of the U.S. government. That could cause flooding in the Barrow area and put some land underwater, but not even the shortest homes or schools would be submerged.

Not to meniton that Barrow is about 15 feet above sea level at this time.

Barrow does, however, face legitimate climate-change threats as one of the few communities in the 49th state where temperatures have actually risen significantly in the last 50 years, according to the Alaska Climate Research Center at the Geophysical Institute at the University of Alaska Fairbanks.

Climate skeptics?

Some will likely be offended to learn the  Center reports that  though “the period 1949 to 1975 was substantially colder than the period from 1977 to 2014…since 1977 little additional warming has occurred in Alaska with the exception of Barrow and a few other locations. The step-wise shift appearing in the temperature data in 1976 corresponds to a phase shift of the Pacific Decadal Oscillation from a negative phase to a positive phase.”

The PDO is an old phenomenon that describes the pooling of warm water in the Gulf of Alaska. That warm water influences the climate of the entire state. To date the PDO appears to have had a greater effect than climate change on most of Alaska with the exception of  Barrow.

And in Barrow the problem isn’t so much warming as it is a seasonal shift. Winter now comes later to the North Slope than in the past. The late arrival means Barrow isn’t safely locked in ice by the time fall storms start raking across the 49th state.

“Since 2002,” according to the National Oceanic and Atmospheric Administration,” the (Arctic) ice pack has retreated, and now, not only are Octobers regularly near the warmest of record, but every October is exceptionally warm.”

And that, not the rising sea level, is what causes the real and immediate problem for Barrow.

“The dramatic decline in sea ice coverage in the autumn means that there is much more open water to the west and northwest of Barrow,” NOAA reports. “On October 13-14, 2012, a strong storm, 500 miles northwest of Barrow, produced coastal flooding in low-lying parts of Barrow.

“….Moderate but steady west-to-northwest winds over completely ice-free waters raised the sea level several feet (There are no tide gauges or other real-time direct measurements of sea level at Barrow. Most of the Barrow area is less than 15 feet above sea level.) Thirty years ago, the exact same meteorological conditions would have had much less open water to work on, and similar flooding would not likely have occurred.”

No houses went “floating inland for miles” in 2012, but some old timers in Barrow said there might have been some structures moved inland a distance, if not miles, in a big storm that brought high water in ’63.

“The October 1963 storm was the worst storm ever recorded by the U.S. Weather Bureau at Barrow,” according to a research paper published in 2004. “Winds reached 25 m/s, (56 mph) the storm surge reached 3.6 m, (12 feet) and wave heights reached 10 feet. Homes, buildings, airplanes, and fuel were lost, mostly within reach of waves or located on eroded bluffs.”

The report makes no claim to houses floating miles away, but as with much of what is reported in the media today, it could have happened. Maybe.

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6 replies »

  1. The Post article was written for an innumerate non-technical audience about a place they will never see. It’s on script so the audience nods and adds Barrow to the list of things they are deep passionate about saving. From what I can tell climate concern seems to be an urban affliction based on a notion the planet should remain in its present state forever. True students of nature who observe things know that nature and the planet are dynamic. Great blog, one of the best on the interwebs!

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    • there is indeed a 3 degree increase over the last 60 years, but what it means is hard to say. as The Alaska Climate Research Center notes: “Considering just a linear trend can mask some important variability characteristics in the time series. The figure at right shows clearly that this trend is non-linear: a linear trend might have been expected from the fairly steady observed increase of CO2 during this time period. The figure shows the temperature departure from the long-term mean (1949-2014) for all stations. It can be seen that there are large variations from year to year and the 5-year moving average demonstrates large increase in 1976. The period 1949 to 1975 was substantially colder than the period from 1977 to 2014, however since 1977 little additional warming has occurred in Alaska with the exception of Barrow and a few other locations. The stepwise shift appearing in the temperature data in 1976 corresponds to a phase shift of the Pacific Decadal Oscillation from a negative phase to a positive phase. Synoptic conditions with the positive phase tend to consist of increased southerly flow and warm air advection into Alaska during the winter, resulting in positive temperature anomalies.” one could, if one wanted to be cute with numbers, claim a 9 degree increase over the past 58 years from about 4 below the norm in 1955 to 5 above the norm in 2013. but that isn’t really how one tracks climate, a long-term phenomenon that operates on the scale of hundreds of years. we do appear to be experiencing a warming trend since the late 1970s. before that, we were experiencing a pretty awful cooling trend. if you were here then (i arrived in ’73 when half the winter in Fairbanks seemed to be 50 below), you’d take this over that. and it is interesting to note the regional variations across the state now. the state has been on something of climate plateau since 1977 with annual means for ’77-2015 increasing slightly in some places but falling in others. the average for that period is 0.3, not 3. how many people were worrying about global warming before ’77? i wasn’t. i probably started reporting on it in the late ’80s or early ’90s, and our temperatures have been pretty stable since then which is all out of wack with common perception and what one would expect with the global CO2 increase. but maybe we’re headed for a big spike. the last two years have been awfully warm.

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  2. 1) End of first graph, “internets” plural. Surely you meant internet singular;

    2) Eighth graph, some words missing, something like, “there you will discover”… Or “There you will learn”…

    Sent from my iPhone

    >

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