Happy Halloween! Official trick-or-treating in my municipality was Friday. It rained quite steadily. We only had 10-15 trick-or-treaters, and are left with about 370 pieces of candy.
The last article in the October, 1957, IGY Bulletin is on the Arctic Program. "The US-IGY Arctic Program includes projects in virtually all scientific disciplines to be studied during the IGY." The article has subsections discussing plans for study in the most of the 14 areas listed in an earlier post:
- meteorology (#2)
- geomagnetism (#3)
- aurora (#4)
- ionospheric physics (#5)
- solar activity (#6)
- cosmic rays (#7)
- glaciology (#9)
- oceanography (#10)
- seismology and gravity (#12,13)
About 50 U.S. fixed stations were set up in the Arctic for the IGY, to be complemented by measurements made from aircraft and rockets. Most studies were synoptic in nature, to be compared to other global measurements, especially from the antipodal Antarctic polar region.
An aside ... On a trip I made to Philadelphia earlier this week, I went to the Wagner Free Institute of Science, established in the mid-1800s (a century before the IGY era) for the education of the general public about natural history. It has an amazing display room still set up in the old-school style with thousands of specimens to illustrate the diversity of the natural world. (Hardly anyone in Philadelphia knows about this museum; it's free and worth a visit.) Some of the display cases were marked as synoptic. The idea was to give a synopsis of different classifications within the animal kingdom, just as synoptic measurements for the IGY were to give a synopsis/summary/ snapshot of a particular geophysical phenomenon at an "instant" of time.
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| Display cabinets at the Wagner Free Institute of Science, Philadelphia |
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A synoptic(al) collection of natural history specimens |
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| A synoptic display case at the Wagner Free Institute of the phylum Coelenterata |
Anyway, here are some highlights of what was planned for the IGY Arctic Program:
Aurora. The two principal objectives were to accurately delineate the northern aurora zones, and to study auroral physics. The most important instruments were twelve all-sky cameras at different stations to photograph aurorae, along with auroral radar stations.
Cosmic rays. The IGY program involved studying the variations in mass and energy of cosmic ray particles, and the intensity of them at Earth's surface and at different altitudes. Lower energy cosmic rays can reach the Earth's surface at the poles, because the geomagnetic flux lines are "open" at high latitudes, as you can see in the diagram in an earlier post. Comparison of cosmic ray fluxes from the two polar regions would shed light on the uniformity of the cosmic ray flux in space and its interaction with the geomagnetic field.
Ionospheric physics. Layers in the Arctic ionosphere are constantly disturbed by atmospheric turbulence, auroral currents, and ion fluxes, but these patterns were not well understood at the onset of the IGY. Ionospheric soundings were planned to compare conditions above the Arctic and the Antarctic and reveal details of the morphology of the magnetosphere.
Geomagnetism. As was posted before, the IGY geomagnetic studies focused on the external component of the Earth's magnetic field, much smaller than the internal component. The more rapid (on the order of seconds) changes in the geomagnetic field were due to this external component, on account of ionospheric electrical currents.
Solar activity. Plans were made to establish a station at College, Alaska, to continuously monitor solar activity during the six-month long polar day.
Meteorology. The article states that "It has long been recognized that Arctic air masses are an important factor in Northern Hemisphere weather." Standard meteorological observations were to made at a number of high latitude stations, along with measurements from balloons and aircraft. In recent years, we have heard of cold weather pushed from the Arctic region into lower latitudes due to behavior of the polar vortex and jet stream, such as occurred in February of his year.
Oceanography. Standard measurements were planned at seven fixed stations and at the two drifting stations. aerial reconnaissance flights were to be used for examining Arctic sea-ice movement and seasonal changes in ice volume.
Glaciology. Morphology, history, and movement of Arctic mountain glaciers, ice sheets, and adrift ice were to be studied, and their connections with meteorology, climatology, and oceanography of the Northern Hemisphere. Climate change studies didn't quite have the urgency they do today, but an IGY goal was to gain a better understanding of past and future climatic shifts.
Aside ... with all the IGY Arctic stations in Alaska, it's easy to forget that Alaska was not even a state yet! The Alaska Statehood Act was signed by President Eisenhower on July 7, 1958 (during the IGY), and became the 49th state on January 3, 1959.
Seismology and gravity. My own geophysical interests and career had more to do with the solid Earth, including the topics of seismology, gravity, (internal) geomagnetism, and heat flow. The article states that "the US-IGY Arctic programs in seismology and gravity are part of the worldwide IGY effort to gather information on the precise shape, or figure, of the earth; on earth tides; on the structure and seismicity of both the crust and interior of the earth; and on related phenomena." Measurements in the polar regions in those disciplines had been sparse prior to the IGY. Seismology and gravity measurements would also be important in better understanding the geology of the Arctic Basin. High precision pendulums could be used for absolute measurements of the Earth's gravity. Seismic stations in Greenland and Alaska could also better detect regional earthquakes.
A final aside ... Did you hear that a large X1-class solar flare on Oct. 28 caused high geomagnetic activity and an unusually low-latitude and intense auroral display (video is from Lapland) yesterday?
On to the November, 1957, IGY Bulletin.
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