Tuesday, September 1, 2009

A New Seamount

On the midnight watch we passed again by the seamount discovered last week:

Polar stereographic image (75deg N), 6X vertical exaggeration, measured in meters. For other images visit LDEO

To chart our course we combine information from a variety of maps and data sources. Very little of the historical information we rely on was produced with GPS or the kind of multibeam echosounder equipment we are mapping with on HEALY, which provides very detailed images of the areas being mapped. Thus, last week we had only a previous contour line to indicate that a small rise might protrude from the seafloor in that spot. The earlier maps gave no indication that the feature would rise more than 1,000 meters or .6 miles from the seafloor, which is required for a seamount. Christine Hedge, the NOAA Teacher at Sea (from Carmel Middle School, Indiana), was standing watch when she noticed a feature emerging somewhat starboard of the planned ship track, and contacted the scientists in charge who redirected the ship so we could map the feature more completely.

While the seamount rises almost 1,100 meters from the seafloor, its peak is still over one and a half miles below the surface of the ocean (rising from 3710 meters to 2622 meters; the 3791 mark shown in the image above refers to the surrounding seafloor, not to the base of the seamount itself). It is located at 81 degrees 31.57N 134 degrees 28.80W, is approximately 14 nautical miles long, 4 nautical miles wide, and oriented N-S. Other images of the seamount may be found at the Lamont Doherty Earth Observatory of Columbia University.

Larry A. Mayer and Andy Armstrong, of the UNH Center for Coastal and Ocean Mapping/NOAA Joint Hydrographic Center, co-chief scientists for HLY0905, were also leading a mapping cruise on board USCG HEALY in 2003 when the feature now named Healy Seamount (after the vessel and its namesake, Captain Michael Healy) was discovered at 78º40’N, 158º 00’W.

Of the new seamount, Mayer says, in Andrew Revkin's DotEarth report:

"The new seamount is small but unusual in its isolation (at least we think it’s isolated — remember we didn’t know it was there - and I suspect there are many others that we don’t know about) — but this one is sitting in the middle of nowhere in the abyssal plain and will only add to the mysteries of the origin of this part of the Arctic."

Source: NYT DotEarth, September 10, 2009

Icebreaking into the Arctic

The USCGC HEALY embarked Barrow, Alaska, in August 2008 to map the US extended continental shelf, or ECS, in the Arctic Ocean (HLY 0805). Healy sailed again from 7 August to 16 September, 2009 (HLY 0905) to continue ECS mapping, joining with the Canadian icebreaker, the Louis S. St.-Laurent. The two vessels mapped together again in 2010 (see HLY1002) and 2011 (HLY1102).

As the only law professor on the science crew, I was along on HLY 0805 and 0905 to better understand
the science behind the legal process that the UN Convention on the Law of the Sea establishes for states making ECS submissions. As to why the US is mapping now, even though it has not yet acceded to the Convention, read on both here, and in the Law of the Sea notes below.

Thanks to
Vermont Law School and especially to Larry Mayer, Director of the University of New Hampshire's Center for Coastal and Ocean Mapping, for making my part in the trip possible.
Thanks, as well, to Adriane Colburn, for opening new windows on and for the deep.