. Carnegie Institution of Washington publication. 246 THE CLIMATIC FACTOR AS ILLUSTRATED IN ARID AMERICA. far as the production of corn was concerned, extremely anti-pleionic or "lean" conditions prevailed over most of the United States, which means that there was an especial deficiency in the rains of June and July. In 1906, on the contrary, only one small area was lean, and even there the deficiency was less than bushels per acre. Throughout all the rest of the country "fat" conditions prevailed—that is, the crop was better than the average. Figures 79 and 80, for the
. Carnegie Institution of Washington publication. 246 THE CLIMATIC FACTOR AS ILLUSTRATED IN ARID AMERICA. far as the production of corn was concerned, extremely anti-pleionic or "lean" conditions prevailed over most of the United States, which means that there was an especial deficiency in the rains of June and July. In 1906, on the contrary, only one small area was lean, and even there the deficiency was less than bushels per acre. Throughout all the rest of the country "fat" conditions prevailed—that is, the crop was better than the average. Figures 79 and 80, for the years 1908 and 1909, illustrate an interesting feature of the pleions and anti-pleions of all sorts of meteorological phenomena, namely, their persistence from year to year in spite of certain changes in form and location. The large anti-pleion in the center of the United States in 1908 has contracted in its east-and-west dimensions and has moved south in 1909, but it is clearly recognizable. In similar fashion the minute anti-pleion over Delaware in 1908 has expanded over New Jersey, Pennsylvania, Maryland, and part of Virginia in 1909. This emphasizes a most characteristic and important feature of the pleions and anti- pleions—that is, their movabihty. By means of a series of monthly charts based on over- lapping means for 12 months and thus eliminating all variations due merely to the succession of the seasons, Ai-ctowski has discovered that a given pleion may last for many years, during which its center moves back and forth in irregular curves whose north-and-south component apparently exceeds the east-and-west. Sometimes they grow weak and tend to divide into two or more sections, and practically disappear, while again they strengthen and gather into strongly localized areas of pronounced intensity. Just where they originate or how they disappear is not yet clear, but apparently they do not often pass from the sea to the land. This much, however, is certain: they are
Size: 1797px × 1390px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1914
