Postwar International Activities

The Soviet North Pole (NP) drifting station program resumed in 1950, and continued until July 1991, with stations NP-2 to NP-31 (Romanov et al., 2000). Most of these were established on multiyear ice-floes. The United States had two stations on "ice islands" that had broken away from the Ward Hunt Ice Shelf (Hattersley-Smith et al., 1952). They were T-3 (originally called Fletcher's ice island) established in 1952 and the Arctic Research Laboratory Ice Station (ARLIS) II in 1961; the others were set up on multi-year sea ice (Sater, 1968). Sporadic work on T-3 lasted until 1974. ARLIS II had a more extensive and successful program from its occupation in 1961 in the southern Beaufort Sea until its evacuation in Denmark Strait in 1965. Many of the synoptic weather observations were reported by radio to the Global Telecommunications System (GTS) and thus incorporated into operational weather maps. The presence of even two reports from the central Arctic proved invaluable in detecting large-scale weather systems within the Arctic Basin. Meteorological data from the NP and US drifting stations, and other Arctic climate data for the period 1951-1990, as well as some historical records have been assembled on CD-ROMs (NSIDC, 1996; Arctic Climatology Project, 2000).

Following World War II, it was decided to hold an International Geophysical Year (IGY), July 1957-December 1958. Considerable emphasis was placed on Antarctic observations, but in the Arctic some specific programs were carried out. For example, McGill University operated the first station in the interior of the Canadian Arctic Archipelago at Lake Hazen, Ellesmere Island (Jackson, 1959), whereas the permanent weather stations in the Canadian Arctic Archipelago were all at coastal sites. Ice Station Alpha in the Arctic Ocean was the first US drifting station with a large, multidisciplinary research program. Russian scientific expeditions were mounted to study the glacial meteorology of the ice caps of Franz Josef Land (Krenke, 1961).

In the mid-1970s, a Polar Experiment (POLEX) was proposed by Soviet scientists at the Institute of Arctic and Antarctic Research, Leningrad, as part of the Global Atmospheric Research Program (GARP) of the World Meteorological Organization (WMO). The US contribution to POLEX-North focussed on increased exploitation of satellite soundings of the atmosphere and surface data buoys in support of improved weather forecasting for northern high and middle latitudes. Although a coordinated program failed to materialize, there was added momentum to the observational activities.

In 1972-1976, a US-Canadian-Japanese program— the Arctic Ice Dynamics Joint Experiment (AID-JEX)—was carried out in the Beaufort Sea. Apart from advances in modeling sea ice dynamics, an important outcome was the improved understanding of the ener gy balance over sea ice. Data from the main experiment in summer 1975 are archived at the National Snow and Ice Data Center. Drifting buoy technology for the Arctic was developed during AIDJEX and this led to new information on surface pressure, air temperature, and ice drift in the central Arctic Ocean. Beginning in 1979, the Arctic Buoy Program was initiated with GARP support by the University of Washington. In 1991, this became the International Arctic Buoy Program (IABP), which now involves eight nations (see Meteorological Stations). Initially, around 20 buoys were deployed, mainly from airdrops, but in the 1990s the number rose to over 30 operating at any time. Data from these are relayed via the Argos satellite system to the GTS. The quality of Arctic surface pressure analyses greatly improved as a result.

The International Biological Program (IBP) included a tundra biome component in the 1970s. Each site carried out detailed climatological measurements, including energy budget studies. There were comparative field measurement programs in 1972 at Barrow, Alaska, Truelove Lowland, Devon Island, and Abisko, Sweden (Barry et al., 1981).

In 1985, a Program for International Polar Oceans Research (PIPOR) was inaugurated by the European Space Agency (ESA). The focus was on satellite remote sensing of sea ice using passive and active microwave data. In particular, attention focussed on the use of synthetic aperture radar (SAR) data from the ESA Remote Sensing Satellite (ERS)-1 in polar regions.

In the 1990s, coordinated Arctic climate studies were organized by the World Climate Research Program (WCRP) (see wcrp/prgs.htm) under the Arctic Climate System (ACSYS) project ( Its central goal was to determine the role of the Arctic in global climate. Its specific objectives were: understanding the interactions between the Arctic Ocean circulation, ice cover, and the hydrological cycle; initiating long-term climate research and monitoring programs for the Arctic; and providing a scientific basis for accurate representation of Arctic processes in global climate models. A particular contribution of ACSYS is the organization of various Arctic data sets on climatic and oceanic conditions including sea ice. ACSYS implementation and achievements are documented on the Web. An important related activity undertaken jointly by Russia and the United States, through the Arctic Climatology Project (2000) of the Environmental Working Group, was the preparation of comprehensive atlases of Arctic oceanography, sea ice, and meteorology/climate on CD-ROM during the second half of the 20th century. Other WCRP projects with Arctic components include the Global Energy and Water Experiment (GEWEX) projects for the Mackenzie GEWEX Study (MAGS) during 1992-1994 and the GEWEX Asian Monsoon Experiment (GAME) (see MAGS involved large-scale hydrological, atmospheric, and land-atmosphere studies within the Mackenzie Basin to improve the understanding of cold region, high-latitude hydrological and meteorological processes, and their role in global climate. GAME began in 1998 with hydroclimatological measurements along the Lena River in Yakutia, related to the Asian winter monsoon.

The Arctic Monitoring and Assessment Program (AMAP) was established in 1991 to implement components of the Arctic Environmental Protection Strategy. Its objective was to provide "reliable and sufficient information on the status of, and threats to, the Arctic environment relating to contaminants" (AMAP, 1997). A further follow-up to AMAP is the current Arctic Climate Impact Assessment (ACIA) project described below.

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