摘要:

AbstractThe three constants of a radiation‐balance equation ‐ albedo, heating coefficient and long‐wave radiation balance at zero insolation ‐ have been derived from linear regression equations relating measurements of incident and reflected short‐wave radiation to measurements of radiation balance (all wave‐lengths) made over nine different associations of natural vegetation and two agricultural surfaces. Albedo was found to be the most important discriminant in the relationship, varying from 0.12 for a pine forest to 0.37 for vegetation in a desert wadi. The diurnal and seasonal variations were small and of limited significance. The heating coefficient varied considerably, both with date of measurement and with vegetation, but no consistent differences could be seen. The values found were very low, even negative on a number of occasions. These were associated with a mid‐day decrease in the long‐wave balance attributed to a marked increase in the long‐wave flux from the sky. The long‐wave balance at zero insolation also varied considerably with date of measurement and type of surface but showed only small differences in long‐term mean values.Daily totals of net radiation balance expressed as percentages of total incoming short‐wave radiation varied from a maximum of 58 per cent for the open water surface of a fish pond to a minimum of 25 per cent for a desert association. The ratio for most vegetation w

ISSN:0035-9009    

DOI:10.1002/qj.49709239112

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThis paper considers the theoretical basis of the Monin‐Obukhov similarity theory for the turbulent, thermally stratified, surface layer of the atmosphere. It is shown that the classical form of the similarity theory cannot be applied legitimately to the variances of the horizontal components of the wind velocity fluctuation. This limitation of the theory has recently been suspected on the basis of observational data, although its theoretical demonstration emphasizes the need for caution when attempting to apply similarity theory to other characteristics of the surface layer turbulence that are currently of interes

ISSN:0035-9009    

DOI:10.1002/qj.49709239113

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe lapse rate of temperature following an individual air parcel is derived assuming continuity of temperature, density, motion, and non‐vertical ascent in a changing pressure field. The result differs substantially in form and sometimes in magnitude from that obtained by the usual theory in which the ascent is strictly vertical and the parcel is discontinuous. When non‐vertical ascent and continuous fields are taken into account, important terms arise when the pressure field varies rapidly with time or along the horizontal coordinates. The importance of the departure of the unsaturated parcel lapse rate fromgc p−1in the computation of vertical motion by the adiabatic method i

ISSN:0035-9009    

DOI:10.1002/qj.49709239114

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe clustering, by wake capture, of thin cylinders and discs as they fall through a viscous liquid has been studied, and the relevance of the observations to the aggregation of snow crystals is discussed. The influence of captured cloud droplets on the orientation and falling motion of columnar and plate‐like snow crystals is inferred from the behaviour, in a viscous liquid, of solid cylinders and discs loaded with small spheres and from the motion in air of loaded discs of thin tissue paper. The orientation in the atmosphere of composite ice crystals in the form of columns with end plates may be inferred from the behaviour of cylinders capped by thin discs in a viscous liquid. These observations on the falling speed, orientation and aerodynamic stability of snow crystals are pertinent to their aggregation into snowflakes, their accretion of cloud droplets and dust particles, and to the optical effects they produce in the atmospher

ISSN:0035-9009    

DOI:10.1002/qj.49709239115

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe discrepancy between some recent computations of the mean meridional mass circulation across the Equator is discussed. It is shown that the most probable toroidal mass circulation across the Equator amounts to about 120.1012g sec−1in winter (December‐February) and to about 180.1012g sec−1in summer (June‐August). In winter the circulation at low altitudes is southward and in summer, no

ISSN:0035-9009    

DOI:10.1002/qj.49709239116

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe variation of the infra‐red solar spectrum with altitude was observed during a balloon flight made on 24 March 1964, from Alamogordo, New Mexico. A water vapour mixing ratio profile determined on the basis of the variation with altitude of the infra‐red solar spectrum in the vicinity of 3,854 cm−1during this flight is presented. This profile is in agreement with the view that the mixing ratio in the vicinity of the tropopause is about 2.10−6g g−1; however, it also indicates that the mixing ratio increases again above

ISSN:0035-9009    

DOI:10.1002/qj.49709239117

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractDuring the period 1954 to 1964 the amount of water was estimated and the depth of the water‐table was measured in a soil profile beneath meadow grass at a site on London clay at Uxbridge, Middlesex.Each winter the soil profile was saturated and draining freely and the water‐table was within six inches of the surface. During the spring and summer the soil profile dried out from the surface downwards with a corresponding lowering of the water‐table. By late autumn the water‐table reached a depth of six feet, and the moisture deficit in the soil profile reached a value of from five to six inches. Re‐charge of the soil profile to the winter conditions occurred in late autumn or early winter.Measurements of humidity, sunshine, wind, temperature and other data were used to calculate the monthly potential evaporation, and this information, combined with rainfall data, permitted the calculation of the total deficit of soil moisture at any time from that held at field capacity.For the particular site investigated, the observed depth of the water‐table at any season varied linearly with the calculated moisture deficit in the soil profile beneath the grass, thus providing a simple method for continuously logging the moisture deficit in the soil. The result also provides a basis for correlating weather data with moisture conditions in the soil beneath roads; the moisture conditions are largely controlled by the depth of the

ISSN:0035-9009    

DOI:10.1002/qj.49709239118

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49709239119

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49709239120

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49709239121

出版商:John Wiley&Sons, Ltd    

年代:1966

数据来源: WILEY