American Magnetic Character‐Figure, CA, Three‐Hour‐Range Indices, K, and Mean K‐Indices, KA, for January to March, 1943

Abstract

Summaries of American URSI broadcasts have appeared regularly in this JOURNAL since the issue for December, 1930.As set forth in this JOURNAL for June, 1937, “The Department of Terrestrial Magnetism and the United States Coast and Geodetic Survey with the cooperation of the United States Army and the United States Navy communication‐services and several amateur radio stations have undertaken to supply the American character‐figure based upon the reports of the seven American‐operated observatories—those of the Department of Terrestrial Magnetism at Huancayo in Peru and at Watheroo in Western Australia, and those of the United States Coast and Geodetic Survey at Cheltenham (Maryland), Honolulu (Hawaii), San Juan (Puerto Rico), Sitka (Alaska), and Tucson (Arizona).” This character‐figure is being designated CA, and its values for the first twelve, the second twelve, and all twenty‐four hours of each Greenwich day for January to March, 1943, are given in Table 1.