THE CLIMATES OF NORTH AMERICA ACCORDING TO A NEW CLASSIFICATION

THE CLIMATIC ELEMENTS OF THE LANDSCAPE ARE ANALYZED. THE CLASSIFICATION OF WORLD CLIMATES DEVELOPED ON A QUANTITATIVE BASIS BY KOPPEN IS REVIEWED. KOPPEN'S SCHEME BRINGS OUT THE GENERAL RELATIONS OF VEGETATION AND SOIL TO CLIMATE OVER THE EARTH, BUT FAILS IN DETAILED LOCAL ANALYSES. A CLASSIFICATION SCHEME IS PRESENTED BASED ON THE PRECIPITATION-EVAPORATION RATIO. GRAPHS WERE MADE OF EVAPORATION MEASUREMENTS AT TWENTY-ONE STATIONS IN THE UNITED STATES, CORRESPONDING MONTHLY PRECIPITATION AND MEAN MONTHLY TEMPERATURE. FROM THESE SEVERAL GRAPHS A SINGLE EQUATION WAS FORMULATED THAT EXPRESSED THE RELATION OF THE PRECIPITATION-EVAPORATION RATIO TO THE TEMPERATURE AND THE PRECIPITATION. THIS FORMULA IS DERIVED. PRECIPITATION EFFECTIVENESS AND TEMPERATURE EFFICIENCY ARE THE TWO MOST SIGNIFICANT CLIMATIC ELEMENTS, AND THE RELATIVE IMPORTANCE OF EACH DEPENDS UPON ITS LIMITING EFFECT. WHERE TEMPERATURE EFFICIENCY IS ADEQUATE, VARIATIONS IN PRECIPITATION EFFECTIVENESS ESTABLISHED THE PRIMARY CLIMATIC BOUNDARY, OTHERWISE TEMPERATURE EFFICIENCY IS THE LIMITING FACTOR AND DETERMINES THE BOUNDARIES. A SCHEMATIC DIAGRAM IS PRESENTED OF THE GENERALIZED DISTRIBUTION OF CLIMATES IN NORTH AMERICA. IT IS CONCLUDED THAT THE ULTIMATE VALUE OF THE GENERAL CLASSIFICATION SCHEME PRESENTED WILL NOT BE KNOWN UNTIL THE CLIMATIC REGIONS OF THE WHOLE EARTH ARE MAPPED AND ARE COMPARED WITH THE DISTRIBUTIONS OF THE VARIOUS ELEMENTS OF THE NATURAL LANDSCAPE.

  • Supplemental Notes:
    • Vol 21, No 4, PP 633-655, 13 FIG, 26 REF
  • Corporate Authors:

    American Geographical Society

    ,    
  • Authors:
    • Thornthwaite, C W
  • Publication Date: 0

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  • Accession Number: 00229156
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 15 2004 2:38AM