INTERNATIONAL GEOPHYSICAL YEAR-PROPOSED UNITED STATBS Pbmbabf
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APPENDIX VII THE INTERNATIONAL GEOPHYSICAL YEAR-PROPOSED UNITED STATBS PBmBAbf The United States program for the ASTROOEOPHYSIW BCEASUIULY~I’JT~ International Geophysical year is de- Many of the most practical and enty- scribed by fields below. It envisages ac- lay activities of man and society sure &dies in several geographical regions of affected and determined by astronomical concern to the Nation: ( 1) The Arctic phenomena. Surveying, whether of con* and sub-Arctic regions ; (2 ) the middle tinental coast lines or real estate lo% latitudes of the Northern and Southern mapping and charting of land and seas Hemispheres, including the United States, tidal currents, magnetic compass and Central America, South America, and radio navigation, travel and conune~~ adjacent stretches of the Atlantic and over land, sea, or air, radio communiCa* Pacific Oceans; and (3) the Antarctic tions, typhoons, duststorms and rainless and sub-Antarctic regions. The effort in regions are typical of the activities and these regions varies with present, sustained phenomena that are closely linked to the geophysical activities in each region and sun, moon, and stars. with technical needs. Existing activities The sun, in particular, dominates of the former kind, whose results will be events and activities on the earth. The made available in the program, aflord a 8un’s radiation-electromagnetic and substantial base for the total endeavor, particle-is the major source of energy and the proposed program represents for the earth’s atmosphere and indirectly those added efforts which are required for all types of life on this planet. Some for advances in geophysics expected from solar effects are obvious to the layman- a major United States activity, in com- the gross diurnal variations in weather bination with similar special. and ex- phenomena, the weather changes by sea- panded investigations by other nations. sons, the temperature differences between Emphasis of much of the program is the equator and the poles. Solar varia- upon the Arctic and sub-Arctic, Antarctic tions are not particularly important in and sub-Antarctic, a few zones in South these connections. Less obvious but of America, and the Atlantic and Pacific equally great significance to modem Oceans. It is not necessary, in many of civilization are the effects of solar activity the programs, to add much activity within on the upper atmosphere. Unusual solar the United States, for normal operations radiation, either in intensity or in kind; provide this data. For example, the strongly influences the upper atmosphere meteorology program includes only a few and, indirectly, not only weather phe- South American stations and work in the nomena but radio communications, radio Antarctic. The data from these regions, navigational systems, and many other added to those from existing Weather civilian and military activities, Bureau stations in the United States and Solar activity has several time scales: in the North Pole regions, will provide Overall activity, measured in a number adequate coverage for the crucial experi- of ways, grows and subsides alternately in ments planned in the Western Hemis- about 11 years-the “sunspot cycle.” phere. Similarly, the ionospheric, auro- Individual active regions on the sun, ral, and geomagnetic programs stress the sometimes marked by sunspots, have life- northern and southern latitudes. times of a few days to a few months, 820814--5B---10 128 124 NATIONAL SCIENCE FOUNDATION changing rather gradually during thai The IGY also &ords an opportunity to time. Spurts of activity, occasionally achieve a marked advance in longitude during “sunspot minimum” but common and latitude measurements. There are during the high activity stages of the 1 l- two kinds of longitude and latitude: Geo- year cycle, occur in some individual solar graphic and astronomical. Geographic regions and last a few hours or a few coordinates must be used in mapping and days, with individual outbursts or flares can only be obtained for the earth as a lasting only 10 to 30 minutes or so. whole by observing the moon or by meas- Variation in solar activity on each of urements of gravity all over the earth, these time scale8 have been shown to be which have never been adequately ob- associated with terrestrial phenomena. tained. Astronomical coordinates can be Many details of these correlations, how- determined accurately only by observing ever, remain hazy because of the many the stars. While these are not useful for interruptions in the record of solar activity making maps, their high precision makes observations. Further ‘correlations of them useful for detecting a possible shift broad implications to science and civilixa- in the distance between two land masses. tion require detailed and comprehensive The longitudes and latitudes of numer- records of solar activity. The chief aim ous points in all civilized countries have of the solar activity work during the IGY been accurately measured so that accurate is to achieve this record by systematic ob- maps of large regions have been possible. servations of the sun, through improved But it has not been possible to extend the coordination of the observing programs of surveys across the oceans because they the solar observatories of the world, and are too wide: There are not islands through more detailed, speedy and mean- enough to use as stepping stones, nor has ingful compilation of observations by co- it been possible to connect the separate ordinated reduction with workers in the networks of longitudes and latitudes with relevant fields of geophysics. each other more accurately than 200 or Solar activity-solar flares, coronal and 300 feet, and the location of some islands chromospheric activity, and sun spots- is uncertain by a mile. The moon, how- will be observed as part of the overall ever, can be used as a stepping stone geophysical program. In particular, solar across oceans, using a new photographic flares will be studied in order to correlate technique that makes it possible to ob- them with changes in cosmic rays, iono- serve the moon with the necessary pre- spheric and auroral disturbances, and cision whenever it can be seen at night. meteorological phenomena. One of the This makes it possible to accomplish as immediate uses to which flare data will be much in a single year as could be done in put during the IGY has to do with the a century by the older methods, provided “Warning Service” program (see below ) . a sufficient number of observatories, well While regularly planned measurements distributed geographically, are included will go on during the IGY, it is especially in the program. The observational tech- important that experiments be conducted nique consists of direct photography of simultaneously throughout the world the moon, the camera being specially de- during periods of unusual activity of the vised to hold the image of the moon sta- sun. The Warning Service will collect tionary among the stars while the expo- data from all fields, as well as solar ac- sure is being made. The probable error tivity, and will broadcast the imminence, of a single observation is about 0.15 sec- onset or presence of unusual geophysical ond of arc, corresponding in general to effeets, such as solar flares, magnetic about 900 feet on the earth. Thus, 200 storms, ionospheric fadeouts and black- observations at each of 2 stations should outs, signaling the observers to proceed give the distance between them with a with their special preestablished study probable error of about 90 feet. The new Programrr. technique adds greatly to the precision FOURTE AFCNUAL RE’kOBT ‘1% ,&h which changes in the qxed of mta- changes precede and control tho8e id the 6011 of the earth can be measured, and Northern Hemisphere,’ or whether both the observational material obtained for these are controlled by upper atmospheric &is geodetic program may be expected to conditions (perhaps brought about by &ed new light on the inner constitution change5 in solar radiation). The world of the earth. line which the United States is most interested in is the 80th meridian, west METEOROLOt3Y of Greenwich passing through the eastern portions of do rth America and the west The atmosphere is the working fluid of coast of South America, making use of an enormous engine which pick5 up heat existing stations in the Northern Hemi- in the tropics and discharges it in the polar sphere. The northern terminus of this In the course of this complex regions. line is Eureka, N. W. T. at 80” N., thermodynamic process, the atmosphere completely equipped with weather instru- Measure- creates winds and weather. ments and sounding balloons. The line ments of temperatures, pressures, humidi- then passes through the joint Canadian- ties, and winds from the few hundred such United States operated Arctic weather stations in the Northern Hemisphere are stations in the Canadian Archipelago and assembled into a picture of the current the Canadian stations in the Hudson Bay state of the atmosphere, and are used to area, entering the United States at Buf- explain the existing weather pattern5 and falo. It hops along a series of United to predict their changes. In spite of the States stations, crosses over to station5 in large increase in number of these sound- the Caribbean, and reaches the Pacific ing-balloon observations in recent decader, Ocean at Balboa. There the presently there exist vast volumes of the atmosphere existing line comes ta an end, well north still unexplored. The relatively known of the equator. portion of the atmosphere is largely lim- It is proposed to extend this line to the ited to the lower reaches of the atmosphere South Pole by establishing eight addi- in the Northern Hemisphere: The air tional weather stations-the minimum maSse5of the Southern Hemisphere and of needed for scientific analysis.