Crew Log 33 - Nome, Alaska

Crew Log 33 - Nome, Alaska

From the Scientist by Dr. R. Michael Reynolds

Tuesday, July 07, 2009

Our track from Dutch Harbor north to Nome crossed the famous fishing grounds of Bristol Bay and the Bering Sea. Twenty thousand years ago this enormous shallow area was once above sea level and is called the "Land Bridge." Also called "Beringia," it was 1000 miles wide and was used by migrating peoples from Asia to enter North America and on to parts south.

THOUGHTS ON NOME
(July 6): We are winding up a pleasant week in Nome, Alaska. Herb and David have provided blogs and photos on our trip across the Bering Sea and some of our activities here. About 25 years ago I was an ice scientist with NOAA and we came to Nome to deploy ice tracking buoys in the Bering Sea. I must say, Nome is not much changed. The saloons are only slightly seedier and the bust of Roald Amundsen still occupies its princely perch at the end of the famous Iditarod dogsled race which goes from Anchorage to Nome. When the "three lucky Swedes" discovered gold here in 1898, Nome became the site of a flood of gold diggers. Gold was on the beach and in the top soil so dredging was carried out on a massive scale.

The flood was not good news for indigenous people and today Nome, like so many cities in the Northwest, has a perceptible problem with alcohol. The main street in town, Front Street, runs parallel to the sea wall. The two sides of the street are telling. On the land side, the good side, one finds in two blocks the Covenant Church, Arctic Trading Post (espresso available), Nome City Hall, Amundsen's bust, and the Sitnasuak Native Corporation. On the other side, the beach side, one finds the Bering Sea Saloon, Nome Liquor Store, Anchor Tavern, Breakers Bar, Board of Trade Bar, Polar Bar, and a 24/7 continuum of patrons. Children are often warned to avoid that side of the street.

But there is much good and we have met many interesting and involved people, native and non-native. The museum, library, churches, and schools have great facilities and the kids we met have bright eyes and curiosity. There are so many pleasant surprises here. One learns never to judge people by their dress or accent. I met Tim, a gold dredger who was, in another life, a marine biologist and high school chemistry teacher. We talked about acidification and the environmental effects of gold dredging (small). Robert Cahoon is a geologist turned gold dredger who came up after our public lecture with questions about the fate of CO2 and deep ocean mixing. These people and just about everyone else in Nome are right out of central casting. One expects John Wayne to saunter in at any moment.

BERING SEA, THE THIN OCEAN
I searched the Internet and found a simple map of western Alaska and the Bering Sea. The map shows the depths of the ocean around the Aleutian island archipelago and the Bering Sea. This map deserves a little study. Our route across the Gulf of Alaska to Dutch Harbor took us from deep ocean where the depths are greater than about 3000 m (12,000 feet) into one of the most shallow expanses of sea in the World, the Bering Sea. During our entire passage from Dutch Harbor, we seldom saw depths greater than about 30 m (100 feet).

Think about that: an area larger than Texas but less than 100 feet deep. (This is said with apologies to Texans everywhere. But the locals say if we cut Alaska in half, Texas would be the third largest state.) Anyway, you might hold a sheet of tissue paper while you think about thinness. The ratio of the thickness to the width of tissue paper is greater than the same ratio for the Bering Shelf. A SCUBA diver could go right to the bottom without special air mixtures. Because it is so thin, the Bering Sea shelf is well-mixed from top to bottom. Bottom friction and a little wind or tidal current are sufficient to completely stir the water and bring up nutrients. In deeper oceans, nutrients (from decomposing plants and animals and feces) sink to the deep water and are lost to the plants at the surface. But here there are plenty of nutrients so productivity and sea life are so abundant.

BERINGIA, THE LAND BRIDGE
About 20000 years ago, just a drop in the five billion year time Earth has existed, was the last ice age. Massive glaciers, up to two miles thick, covered Canada and America as far south as Oregon and Pennsylvania. The water for these glaciers lowered the sea level by 100 m (300 feet) so that the Bering Sea and Chukchi shelves were exposed land that connected Asia with North America. The "bridge" was up to one thousand miles wide. This swath of exposed land is called "Beringia," and it was a major pathway for people from Asia to cross to North America.

Since that time, sea level has risen by an average of 30 centimeters (1 foot) each century and with global warming that rate has increased significantly. Satellite studies show that almost all of the Earth's 160,000 glaciers are shrinking at an accelerating rate. It is predicted that by 2050 (that's forty years folks) the Rockies, Cascades, and Glacier National park will have lost almost all of their glaciers. My friend Ron Lindsay, a satellite ice scientist at the University of Washington, is troubled by predictions that there will be no more Arctic ice by 2013 and how that will affect his job security. I hope to talk about sea level changes in another report.

ICE AND THE NORTHWEST PASSAGE
We are now quite focused on the breakup of the ice from Barrow and along the coast to the East. The Bering Straits seems to be clear. One can look at a web camera looking at Russia across the straits (http://209.165.175.132/sample/LvAppl/lvappl.htm). We feel secure Barrow will be open. A Barrow cam (http://www.gi.alaska.edu/snowice/sea-lake-ice/barrow_webcam.html) shows a tongue of ice that has us a little worried. Oh yes, check out the view of bustling downtown Barrow in the camera view.