Arctic Sciences

Abstract The processes controlling advance and retreat of outlet glaciers in fjords draining the Greenland Ice Sheet remain poorly known, undermining assessments of their dynamics and associated sea-level rise in a warming climate. Mass loss of the Greenland Ice Sheet has increased six-fold over the last four decades, with discharge and melt from outlet glaciers comprising key components of this loss. Here we acquired oceanographic data and multibeam bathymetry in the previously uncharted Sherard Osborn Fjord in northwest Greenland where Ryder Glacier drains into the Arctic Ocean. Our data show that warmer subsurface water of Atlantic origin enters the fjord, but Ryder Glacier’s floating tongue at its present location is partly protected from the inflow by a bathymetric sill located in the innermost fjord. This reduces under-ice melting of the glacier, providing insight into Ryder Glacier’s dynamics and its vulnerability to inflow of Atlantic warmer water.

Ringed seals (Pusa hispida) are broadly distributed in seasonally ice covered seas, and their survival and reproductive success is intricately linked to sea ice and snow. Climatic warming is diminishing Arctic snow and sea ice and threatens to endanger ringed seals in the foreseeable future. We investigated the population structure and connectedness within and among three subspecies: Arctic (P. hispida hispida), Baltic (P. hispida botnica), and Lake Saimaa (P. hispida saimensis) ringed seals to assess their capacity to respond to rapid environmental changes. We consider (a) the geographical scale of migration, (b) use of sea ice, and (c) the amount of gene flow between subspecies. Seasonal movements and use of sea ice were determined for 27 seals tracked via satellite telemetry. Additionally, population genetic analyses were conducted using 354 seals representative of each subspecies and 11 breeding sites. Genetic analyses included sequences from two mitochondrial regions and genotypes of 9 microsatellite loci. We found that ringed seals disperse on a pan-Arctic scale and both males and females may migrate long distances during the summer months when sea ice extent is minimal. Gene flow among Arctic breeding sites and between the Arctic and the Baltic Sea subspecies was high; these two subspecies are interconnected as are breeding sites within the Arctic subspecies.

A flexible configuration for an array of sensors has been developed for measurements in energetic regions of the ocean where the flow has high spatial and temporal variability. Central to the system is a two-axis electromagnetic current meter that measures the flow through a ducted volume containing a uniform magnetic field and nonprotruding electrodes flush with the duct surfaces. This geometry minimizes the electrode boundary-layer effect on the output, thus improving calibration and reducing fouling and damage potential. An inexpensive amplifier designed for low signal-to-noise ratios is employed to produce very low zero drift during operation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Statistically significant correlations are demonstrated between annual mean column ozone data collected at mid‐latitude sites [Kerr, 1991] and mean annual and winter sea ice extents east of Greenland and in the Barents and Kara Seas. These results are discussed with reference to the locations of the correlated parameters relative to the “Basic Pattern” of stratosphere‐solar flux correlations [Labitzke and van Loon, 1992]. Possibilities for underlying linkage mechanisms are considered and related to recent decreasing hemispheric ozone level trends.

The last 20 years have seen renewed interest in research in the Arctic. This research has shown us that the Arctic Ocean is a vital part of the world ocean-climate system with a profound influence on the "conveyor belt" circulation of the ocean's deep waters. The formation of abundant and dynamic sea ice, low temperatures and high winds in the Arctic affect the entire Arctic system and makes travel, research and transportation in the region especially difficult, dangerous and expensive. These changes, a natural result of warming of the Arctic, increase not only the breadth of important basic research needed, but because of current trends, elevate the level of required research to include an emerging list of applied and engineering requirements. Observed changes in the Arctic are altering its role in the world - in areas of commerce, transportation, resource extraction and national security. Only a continued aggressive research program employing satellites, aircraft, ships and submersibles can keep our strategic position in the Arctic at the level necessary for our continued role as an Arctic nation.

Scientific evidence indicates that global climate changes, and the most rapid changes are in the Arctic. Northern temperatures have increased twice as fast as elsewhere, the areal extent and thickness of Arctic sea ice have decreased dramatically, sea level rises as oceans warm and as glaciers and icesheets melt, and the ocean becomes more acidic as it absorbs atmospheric carbon dioxide. Changes in climate, as well as advances in technology, and the demand for resources have resulted in a newly accessible Arctic Ocean that invites to commercial fishing, shipping, tourism, mineral, and energy extraction interests and catches the attention of the US Coast Guard and the US Navy, among others. Many activities associated with these interests have implications for sound in the sea, and this presentation will present some of these at an overarching level. The United States has barely begun the baseline oceanographic research necessary to support national and international goals for ecosystem-based management and marine spatial planning in the Arctic Ocean. The US Arctic Research Commission, an independent federal agency, that advises Congress and the Executive Branch calls for Arctic Ocean research that would help policy makers address these issues.

During the Second World War and afterwards, the existence of the Soviet Nuclear Weapons Program provided a small nucleus of scientists free from party interference with their activities, and these scientists, recipients of numerous awards, both national and international, up to and including several Nobel Prizes, are well known in the Western scientific and political literature. This situation is well described by Holloway, among other historians. Lev Altshuler, (9/11/1913-23/12/2003) who was as scientifically accomplished as any of the others, has not been as broadly recognized. This is for a number of reasons. He was not widely traveled, did not speak English, and was rather shy and retiring outside his Russian scientific circles. He was a man of the highest scientific integrity and this led to conflicts with party bureaucrats, and he had no compunctions about aggressively defending his beliefs. In the course of his programmatic activities, he also became the father, as it were, of an entire area of physics; the use of high dynamic pressure to study the properties of materials under extreme conditions. Lev Vladimirovich Al’tshuler was bom in Moscow on 9 November 1913, the son of Anna Esfir’ Kershner-Al’tshuler (1881-1968) and Vladimir Altshuler (1882-1965), a lawyer who was one of the active leaders of the Russian revolution. The senior Al’tshuler held a number of high posts under Stalin, but fortunately avoided being a victim of the many purges taking place during that period. Mrs. Altshuler was a homemaker, raising three children and being a center of a “spiritual gravitational anomaly” as described by her children, with intellectual pursuits for an entire extended family. Altshuler had a brother, Sergei (1909-1979), who was a science historian and a sister Olga (1912-1992), a chemist. In the early years, Vladimir Al’tshuler did a number of tasks in support of the revolution. At one point in time, he was given the assignment of delivering a certain sum of money to V. I. Lenin, at that time residing in Zurich. Upon arriving in Zurich, the elder Al’tshuler deposited the funds at a storage facility at the Zurich railway station, and set out to find Lenin. Upon finding him, Al’tshuler suggested that he might join him for a cup of tea. Lenin immediately demanded that Al’tshuler return to the station and recover the money and bring it to him. “Then, we can talk about a cup of tea”.