ISSN:0035-9009    

DOI:10.1002/qj.49707130701

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49707130702

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49707130703

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49707130704

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49707130705

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

摘要:

AbstractTwo separate equations for the barometric tendency at a fixed point, or the height tendency of a rpessure surface are derivedafrom the hydrostatic equation, and (b) from the equations of motion.The hydrostatic tendency equation, which represents a modification of the Margules—Bjerknes equations, relates the barometric tendency (or the height tendency) to the winds integrated through isobaric layers, and also to the patterns of contours and “thicknesses” of the layers. The separate contributions to the pressure variations rendered by the thermal wind, the cyclostrophic components and the horizontal divergence are identified and discussed. Methods of identifying the layer, or layers, that constitute the site of the processes and of assessing the magnitude of their contributions to the pressure variations are outlined. The reaction of the pressure distribution at sea level to the circulation aloft is discussed in some detail, particularly wit regard to the travel and development of cyclones, anticyclones, etc.The dynamical tendency equation relates the barometric tendency to the accelerations integrate through isobaric layers. A brief discussion of this equation in relation to typical circulations is

ISSN:0035-9009    

DOI:10.1002/qj.49707130706

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

摘要:

AbstractIt is shown that so far as pure advection is concerned, entities like density, density discontinuity (front) and humidity mixing ratio move with the wind at the level considered. Any disparity between actual movement and streamline movement must be put down to development.A pressure‐field at a given level is advected in a direction and with a speed given by the average wind at will levels above that level. Similarly the difference in pressure between two fixed levels is advected by the average wind between those levels. Any disparity between actual movement and that determined by the average wind must be attributed to development.The advection of contours and thickness lines can be inferred from advection of isobars and pressure‐differences in the absence of development.Winds are normally available up to pressure levels of 60 mb. in the British radiosonde ascents, so that over 90% of the atmosphere can be utilised in computing average winds. There is reason to believe that averages based on this data will be sufficiently accurate to give a satisfactory measure of advection of tropospheric phenomena.The average wind may also be taken as a measure of frontal advection, in the sence that the frontal through of pressure must be advected in the same way as other pressure fields when development is not of importance.A measure of upward motion might be obtained on some occasions from a consideration of the conflicting advections at different levels.The theory of the pressure‐field being advected by the average wind at all levels accounts satisfactory for the fact that systems with “solid” wind currents do not move. An explanation of “thermal steerin

ISSN:0035-9009    

DOI:10.1002/qj.49707130707

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49707130708

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49707130709

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY

摘要:

AbstractThe meteorograph records of the almost daily ascents over England during the months of April, 1939, and September, 1930, have been evaluated according to a method described in an earlier paper. (Q.J.70, 1944, p. 293).The humidities so obtained indicate (1) that supersaturation with respect to ice is very frequently found in the upper troposphere; (2) that, within the stratosphere, dry air of a humidity mixing ratio of about 10−5sometimes does occur, which can only be explained as tropical stratosphere air; (3) that, on one occasion, very dry air from the stratosphere appears to have been drawn into the uppermost regions of the tropospher

ISSN:0035-9009    

DOI:10.1002/qj.49707130710

出版商:John Wiley&Sons, Ltd    

年代:1945

数据来源: WILEY