CORRESPONDENCE Comments on Interactions of Circulation and Weather Between Hemispheres ADALBERTO SERRA

• Main Authors: Serviqo De Meteorologia, Rio De Janeiro
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Pacific; Chaco; aleutian low; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.395.1564; http://docs.lib.noaa.gov/rescue/mwr/092/mwr-092-09-0427.pdf

Namias [l] published an interesting article on interactions of circulation and weather between hemispheres. I think, however, that his findings could be readily explained through our principle of symmetry, as presented in [a]. There, we tried to prove that, in spite of geographical factors, circulation always proceeds symmetrically for both hemispheres: for pressure is a continuous element, high (or low) values occurring simultaneously on the two margins of the equator, where no intense gradients can form. Geographical factors, however, do modify the final results: an intense Chaco Low, in South America, the result of local heating, faces an Azores High, resulting from oceanic conditions. If the former intensifies, the latter does not disappear, but weakens, as crossed by a trough, etc. The figures contained in Kamias ’ article confirm our hypothesis: In figure 2a, the Icelandic Low is located at 40°W., in symmetry with another Low over northeastern Brazil, at 45’W. In figure 2b, the Low situated at 55OW. in the North Atlantic has its symmetrical image in the Low at 55OW. in southern Brazil. In figure 2a, pressure was very elevated in the Bermuda High, at 7OoW., and also, symmetrically, in the Chile High, which faces a Canadian one. No Bermuda High existed in figure 2b, resulting in a weaker Chile High, and in an extended low pressure area over the equatorial Pacific. In figure 2b, both Azores and South Atlantic Highs are centered at the same meridian, 15OW. Also the Aleutian Low, much displaced to the east, is situated in the same longitude as a South Pacific trough (16OOW.). Finally, one must note that in January 1950 (fig. 4a), rains were zonally arranged, in response to the zonal disposition of 700-mb. contours (fig. la) in the Northern Hemisphere. For January 1958, meridional rain bands in South America (fig. 4b) are symmetrical with the meridional contours on the 700-mb. chart (fig. lb), which encircle the upper trough. The true explanation of the tropical rain bands must be left to another Note, as it ...