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Examines the regional differences in the world atmospheric circulation. Description of the geographic pattern of climate; Separation of boundary zones; Generation of climatic gradient in the moving air by factors which tend to produce a steep weather.

Presents a response to the comment on the article written by John E. Oliver entitled "A Genetic Approach to Climatic Classification," previously published in "Annals of the Association of American Geographers." Demonstration of a compact clustering of average monthly values by the stations designated as dominated year round by mP air masses; Question on the feasibility of using a single data point on the thermohyet diagram as representative of the ultimate equable maritime climate; Assertion on the usefulness of climate classification

Presents a reply to the comment of the article written by John E. Oliver entitled "A Genetic Approach to Climatic Classification," previously published in "Annals of the Association of American Geographers." Selection of poor examples in the quest for stations that do not fit the scheme suggested in the paper; Questionability on the usage of short-term and old data in any climatological analysis; Role played by air masses in maritime origin in the determination of the summer climate of some continental stations.

The mean temperature for the Northern Hemisphere had a warming trend from 1890 to 1950 and a cooling trend since 1950. The eastern and central United States had colder temperatures in 1961–1970 than in 1931–1960. The temperature changes were associated with an adjustment of hemispheric circulation from more frequent zonal flow between 1900 to 1950 to more frequent meridional flow since 1950. Regional variations in magnitude and direction of the change were largely related to position in relation to the upper air westerly wave pattern. Time series of individual circulation indices tend to resemble the step function model of climatic change. [ABSTRACT FROM AUTHOR]

The article presents a study which describes a search for patterns of species density in an area of strong climatic gradients at Connemara, in the Western Ireland. It reports that the stone-walls on south-facing slopes in Connemara have smaller values for species density than do those on north-facing slopes. It mentions that the pattern of species density appears to reflect the aspect of the regional slope, and the degree of exposure to maritime air masses. It notes that the within any aspect class, the species density of old stone walls increases with the distance inland from the south-west coasts of Connemara.

The article focuses on the prevailing winds of the U.S. The continental area of the U.S. lies almost entirely within what is generally known as a belt of prevailing westerly wind. These are members of the general atmospheric circulation. They would, however, blow from a general westerly direction much more distinctly if there were no North American continent with its seasonal changes of temperature and of pressure. The local influences of the changing seasonal pressures over the continent and over the adjacent oceans are, to a large extent, paramount to the general control over air movement exercised by the differences of pressure between the equator and the higher latitudes.

An air mass frequency model is constructed to facilitate the formulation of a genetic classification of climate. The model uses Venn diagrams to distinguish three basic climatic regimes, each determined by the relative dominance of air masses: the dominant regimes, where a single air mass dominates all year; the seasonal regimes, determined by seasonally dominant air masses; and the compound regimes, with no dominant air mass. Different climates within each regime are distinguished by actual air mass types. Monthly air mass dominance is determined from actual station surface data for application of the model to world climates. This is completed by analysis of monthly data plotted on modified climographs and by the construction of a monthly air mass identification chart. The proposed system is illustrated by Australian data. [ABSTRACT FROM AUTHOR]

The urban energy balance climatology of the city and man in the Los Angeles basin was examined during a cloudy day ("Catalina eddy") in September. 1968 from about sunrise to sunset, by measuring or estimating solar radiation, net radiation ground heat flux, actual surface temperature, terrain radiant temperature, radiant sky temperature, and dry and wet-bulb temperature for the physical urban interface. An analogous theoretical model attempted to define the input of energy to the human interface via the solar heat load, and the disposal of human net radiation was shown via the channels of latent, sensible, and body heat flux. In spite of an apparent uniform cloud cover, the energy parameters had considerable area! variation in intensity and trend During the daylight hours seventy percent of the solar radiation was absorbed .An additional thirty-two percent was removed by longwave radiation. Of the net radiation received on the dry surface (forty-seven Percent of solar radiation), about eighty percent was disposed via sensible heat flux, and the remainder entered the pavement as storage Air temperatures taken at shelter height were out of phase with the ongoing energy regime and were deemed of dubious value in urban climatic studies. Urban man received only thirty-seven percent and seventy percent of the values available at the horizontal pavement for solar radiation and net radiation, respectively. A series of empirical and theoretical models show high correlations with the observations. It appeared that solar radiation and net radiation (physical and human) could have been estimated via the solar constant and appropriate transmissivities. [ABSTRACT FROM AUTHOR]

Investigations near some of the icecaps of central Iceland show that pressure and winds are markedly affected by the presence of the icecaps under various synoptic conditions. The main effect is of wave formation and descent of dry air, coming predominantly from Polar or Arctic air masses, and the descent of this air is associated with a belt of severe soil erosion in south and central Iceland. A similar effect can also be detected in northern Iceland.

Examines the differences in circulation patterns of climatology between the two eastern littorals in the northern hemisphere. Interception of the ground by the subtropical ridge in East Asia; Role of the trade-wind inversion as a lid to oppose strong convection; Description of the rhythm of the winter monsoon in East Asia.

Focuses on topics related to zonal indices as related to the winter climate in East Asia. Three basic zonal currents in the general circulation of the atmosphere; Computation for local zonal indices; Frequency of indices; Relationship between zonal indices and centers of action.

Explores data on the global patterns of monthly soil temperature distribution. Influence of the ground on the microclimate and topoclimate of a place; Involvement of air masses in general circulation; Effect of frost and extreme temperatures on engineering designs.

Presents a comparative study of dry western littorals. Speculation about the causes for the extreme aridity; Theoretical knowledge of the atmospheric processes at work; Correlation between spatial variations of sea temperature and precipitation averages.

The article reports on the physical climatology of Amchitka Island, Alaska. It states that the extreme variability of surface-wind directions at Amchitka is a result of a high incidence of migratory pressure systems. It also mentions that fog is dominant during the summer months because the water warms more slowly than the air that flows over it. It also forwards that frequent migratory storms and the marine influence of the Pacific Ocean to the south and the Bering Sea to the north are the main factors influencing the weather and climate of this island.

Comments on the article written by John E. Oliver entitled "A Genetic Approach to Climatic Classification," previously published in "Annals of the Association of American Geographers." Utilization of air mass in meteorology; Importance of air mass as a device for summarizing several kinds of information about atmospheric environment; Alleged inability of Oliver's paper to establish the value of air masses.

Comments on the article written by John E. Oliver entitled "A Genetic Approach to Climatic Classification," previously published in "Annals of the Association of American Geographers." Remarkable features on the genetic approach of Oliver to climatic classification; Determinants of air mass provenance; Illustration on the weakness of the classification; Expectation on a scheme that classifies air masses by temperature without regard to the season of the year.