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The article presents observations on microclimate and vegetation interrelationships on the Accra Plains in Ghana. The paper aims to shed light towards a better understanding of microclimate and its interrelationships with the vegetation of the southern savanna zone in Ghana which was known as the Accra Plains. It carried out a measurement of microclimate and transpiration during a complete 24 hour period during the dry season. It set up seven microclimatological stations in a characteristic tree and shrub clump and the surrounding grassland.

The primary purpose of this paper is to analyze the "determinants" of migration between Standard Metropolitan Statistical Areas (SMSA's) in the United States. The magnitudes in which various factors have influenced inter-SMSA migration are estimated both for the country as a whole and for individual SMSA's. The "migration elasticities" estimated for individual SMSA's are in turn used to test several additional hypo- theses concerning migrant behavior. Other similar migration studies have found "wrong" signs or insignificant coefficients on certain variables a priori thought to play a crucial role in the migration process. Finally, we present clues to the causes of such "surprising" results. [ABSTRACT FROM AUTHOR]

Focuses on written structures for presenting the geography of regions. Forms, such as land forms, observable climatic phenomena, drainage conditions, soil character and character of vegetation; Pattern, such as land form arrangement, vegetation pattern; Association, such as drainage form and pattern in their physical relation to the land form and pattern; Principal method description.

This treatise is a summary of the temperature aspect of climate only. Concise statements of the ways in which certain aspects of climate differ from place to place are given in some texts and treatises dealing with meteorology and climatology. The aim of this paper is to point out and explain those relations which correspond, in so far as the nature of the subject permits, to the laws of other sciences. Some of the "laws" that have been included are, laws concerning the heating and cooling of the earth, distribution of heat in point of time, distribution of heat over the earth, delay of heating and cooling, diurnal range and seasonal range.

This paper presents procedures whereby the symbolization of Thornthwaite's climatic classification may be quickly and accurately determined by use of graphs and nomograms. Potential evapotranspiration adjusted for months and latitude of the station is accomplished graphically. Soil water storage, soil water deficiency, and soil water surplus are determined by the Thornthwaite accounting procedure and, once determined, the symbolization for the complete climatic designation of the station is obtained by further graphical means. [ABSTRACT FROM AUTHOR]

In this paper harmonic analysis is employed to investigate regional variations of the annual march of precipitation over Canada. In order to examine the regional variations of the annual march of precipitation, the researcher is confronted with the problem of presenting variations of space as well as time. A method of objectively describing and mapping these space-time characteristics of precipitation is that of harmonic analysis. Before proceeding to examine the area distribution of the two major variance components, the annual and semiannual, it is useful to establish the distribution of the total variance and also the relationship of the two major components to the total variance and to one another.

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.

It is well known that textile fabrics lose strength when subjected to unprotected outdoor exposure, and the amount of strength lost for a given period of time, or for a given number of sun-hours as measured by the Campbell-Stokes apparatus, may vary considerably according to the nature of the fibre and to the climatic conditions prevailing at the exposure site. From data recorded at eight exposure sites in the United Kingdom during 1961 and 1962, it is possible to draw certain conclusions. Thus, in rural areas, such as Pontypool (Mon.), Invergowrie (Perth), and Carlton (Durham), where 'clean' or unpolluted atmospheres might be expected to exist, an 11-oz/yd² cotton duck was found to be more resistant than either a 10½-oz/yd² nylon or a 14-oz/yd² Terylene fabric. In semi-rural areas, such as Lanark and Farnborough (Hants.), 11-oz/yd-²cotton duck appeared to be as resistant as Terylene. It was only in urban areas, such as Didsbury and Droylsden (Lanes.) and Bradford (Yorkshire), that cotton was found to be inferior to Terylene and to a less extent to nylon. The 16-oz/yd² cotton fabric was found to be more resistant than the 11-oz/yd² one. [ABSTRACT FROM AUTHOR]

The article presents a study on the light reaching the ground vegetation in the high forest phase and its relation on the differences in forest structure of two selected sites, where one is on the slopes of Mount Andes and the other is at the extreme western edge of the Amazon basin. The authors state that their observations and analysis have enabled them to associated some of the differences between the two forests with differences in light climate. They mention that the interactions between light and other factors, specially root competition, may be very important. They believe that future studies on light as an ecological factor in tropical forests will most productively be aimed to the reaction of individual species to light at various stages of growth.

The article presents an environmental analysis of the savanna vegetation in Northern Nigeria. The study indicates that soil parent material is not a major factor in the arboreal vegetation of an area. It reveals that the main factors are the water availability in the soil and the degree of human interference. The factors control the general ordination of both noda and groups, soil water and human interference. Moreover, the general case differences in soil parent material do not necessarily imply differences in the arboreal vegetation.

The article discusses a study of the winter annual Teesdalia nudicaulis which is based on field observations in the East Anglian Breckland in England and on pot experiments. The monthly means of some climatic factors which are recorded in or near the Breckland are shown. It considers in more detail the soil moisture likely to be experienced by Teesdalia in the Breckland during late winter, spring and early summer. Careful excavation of root systems showed that the roots of almost all Teesdalia plants growing on undisturbed soil are confined to the top 4 centimeters of soil.

The article examines the relation of evaporativity to plants and animals. It investigates the conditions determining rates of evaporation from organisms in freezing weather. It discusses some new arrangements whereby porous-porcelain atmometers may be guarded from frost injury in short period of freezing weather. The experimentation was carried out at the Laboratory of Plant Physiology of the Johns Hopkins University in Baltimore, Maryland during the winter of 1927 to 1928. It emphasizes that direct measurement of evaporation in freezing weather may be based on the vaporization of either liquid or solid water.

The paper gives a short account of some hydroclimatical factors and their importance for the habitants of arctic and alpine lakes. The differences in distribution of solar energy are briefly discussed. Few examples of plankton communities in arctic and alpine lakes are given together with some remarks about the geographical distribution of plankters. [ABSTRACT FROM AUTHOR]

Fourier and spectral analysis of rainfall records at 163 South African stations over the period 1910-1969, and at thirty-nine stations from 1880–1969, shows that cyclical fluctuations with periods of about 18–20, 13–15, 10, 4.5, 3.5, 2.8, and 2.3 years account for much of the observed rainfall variance over the country. These fluctuations exhibit distinctive regional distributions that appear to have changed little over the last century. [ABSTRACT FROM AUTHOR]

Colluvial mantles on the mountains of southwestern United States are believed to have formed during colder climates associated with the last glaciation. They imply mean temperatures 10-11°C. lower than those of today and a depression of the timber line by 1,300-1,400 meters. Evaporation rates were about half the present values and by estimating runoff it is possible to reconstruct the full-glacial hydrologic budget of Pleistocene closed lakes. Precipitation was eighty to ninety percent of present values and there was no glacial pluvial. Pollen data can be reconciled with the proposed cold dry climate which has modem homoclimes at higher altitudes and latitudes. [ABSTRACT FROM AUTHOR]

Examines the complexity and dynamics of climatology. Investigation of the three climatic methodologies; Distinction between dynamic and synoptic climatology; Description of climates.

Focuses on the nature and origin of the Canadian Dry Belt, dry regions in the Great Plains of North America. Measurement of annual precipitation; Variability of precipitation; Classification of climate.

Discusses the climatic maps of proper China and Manchuria according to the Thornthwaite 1948 classification. Formula for computing the potential evapotranspiration; Presentation of climatic conditions; Classes of maps presented by Thornthwaite.

Discusses some of the methods whereby the climatological record is being put into a shape more valuable to the meteorologist and the regional geographer. Synoptic climatology; Problems of a quantitative treatment; Statistical specification of the pressure pattern.

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.

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.

Continentality can be incorporated into traditional climatic classifications on a basis that is comprehensive, sensitive, consistent in its criteria, and orthogonal with respect to other classificatory criteria. Two oceanic (ultraoceanic and oceanic) and three continental (subcontinental, continental, and ultracontinental) subdivisions provide effective, yet efficient, resolution of the continentality spectrum. The major groups or extratropical climates, the global distributions of sea ice and permafrost, and the distribution of major vegetation types in Alaska are related to climate in traditional terms and in terms of continentality. [ABSTRACT FROM AUTHOR]

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]

A brief survey of the woods and forests of Staffordshire, their past history, their extent and composition, and their present day problems and potential. [ABSTRACT FROM AUTHOR]

The article explores the distribution of Empetrum nigrum in the British Isles. The authors discuss the geographical and altitudinal distribution, climatic and topographical limitations as well as the substratum of Empetrum nigrum in the island group. They also tackle the presence of Empetrum nigrum in forest communities, dry heath communities, wet heaths and peatland communities and grasslands. Moreover, they discuss the response of Empetrum nigrum to several biotic factors as well as its performance in various habitats and the impact of frost and drought in its distribution.

The article offers information on the herb vegetation of an oakwood area on Loch Lomond in the Highlands of Scotland. The oakwood area is comprised of four islands, Inchcailloch, Clairinsh, Creinch and Torrinch. While Torrinch and Clairinsh are underlain by Lower Old Red Sandstone conglomerates, Creinch and Inchcailloch are formed by a band of dolomite fault rock. The soils in the site have ten profile types including podsols, brown earths, and peaty soils. The entry also provides information on Loch Lomond's climate, biotic factors, and history.

The article focuses on the study conducted which highlights the investigation on the features of central Snowy Mountains in New South Wales. The study cites investigation on the description of geology, climate, flora and vegetation physiognomy of the central Snowy Mountains. The study also mentions that floristics and ecological connectedness of 17 alpine plant associations and provisional institutions are given consideration in the investigation. Further, the study also features the comparison on the alpine vegetation in New Guinea and northern Europe.

The article presents the study regarding the vegetation of the different types of soil parent materials recognized in the Middle Gongola region. The seven parent materials are analysed separately and a total of 26 distinct noda emerge. In 14 cases, noda remains separate and each forms the basis of a group,while in three cases, two noda join through mutually associated plots to bi-nodal groups, and in two cases three noda combine to form three nodal groups. It states that in general, the groups are topographical or physiognomic units or, both which are usually recognizable on aerial photographs can be used as mapping units.

The article describes the microclimates of forest and savanna sites in the Olokemeji Forest Reserve in Nigeria. This description is based on rainfall and temperature data from Olokemeji and for other climatic elements, on data from Ibadan. The mean length of dry periods is less than 4 days during the wet season and rises to over 50 days during the dry season. The results show that Olokemeji has a climate typical of it area of the country and of the forest/derived savanna boundary area in west Africa.

The article describes the plant ecology of Dungeness in England. The climate of Dungeness is a severe one for plant growth, with high temperatures in summer and low in winter. They have presented several features that contribute to make the Dungeness succession of unique interest. The features include very large and homogeneous area, and there is no soil in the original shingle and the stones are remarkably evenly graded so that the succession has to start from the very beginning. They have also found out that the Dungeness heath is completely independent of the maritime fringe and thus is comparable more to the shingle of inland areas than to other maritime habitats.

The article focuses on the analysis of growth of Molinia caerulea and Dactylis glomerata or peat. There were two climate environments were employed in an attempt to separate the relative effects of mineral nutrition and climate on these grasses. The object of these studies are to define the ways in which plant growth is limited on high-level blanket peat at Moor House National Nature Reserve where the temperatures are similar to those at sea level in Iceland. The result of Molinia at Moor House in the second year reveal both higher mean yield values for plants which received nitrogen in the first year and substantial result for Dactylis in the first year.

The article presents a study which examines the distribution of certain plant species in similar desert and steppe soils in Central and Northern Iraq. According to the result of the study, the climate, salinity and degree of aeration of the soil are very important in controlling the distribution of these plant species. It was found that the degree of aeration of the soil proved to be most important, while mechanical penetration and water absorption by roots was found to be comparatively unimportant except at very high dry densities.

The article presents a study on the climatic and edaphic gradients of chalk grassland in three areas including Cambridge, North Dorset and East Riding in Great Britain. The study of distribution patterns in one area concluded that topography is one of the most significant factors regulating the dispersion of chalk grassland species. It showed that the primary axis of plant distribution is from south-west to north-east and co-occurs well with the local climate studies. Moreover, the distribution in each area was equally explicated in terms of humidity.

The article focuses on the survey which assessed the environment of Carneddau, a group of mountains in Snowdonia, Wales. The survey described the environment of a mountain massif in Snowdonia, the Carneddau, under topography, climate, rocks and soil, and land management. It revealed that the sub-mountain vegetation is divided broadly into grassland, heath and bog, which occupy most of the zone below the potential altitudinal tree-limit, but above the limits of enclosed land. The survey also found out that the land management practices appear to be causing economic degeneration of the hill-lands and moor-burning is perceived as a particularly harmful custom.

The article presents a study which assesses the factors that affect the formation of cactus scrub and dry evergreen bushland and thickets in well-drained lands in Jamaica. It is observed that the water-supply capacity of the soil influences the formations of the plants especially the soil overlying porous limestone. The growth is also attributed to the edaphic and topographic factors which determine the distribution of the bushland and scrubs. It concludes that the vegetation is influenced by soil-moisture relations resulting from climate, soil and topography.

The article presents a discussion about the observations gathered about the existence of Theobroma Cacao in the island of Fernando Po. The article explores the effectivity of the fungicide control of cacao black-pod disease or the Phytophthora palmivora and analyzes other aspects of cacao yields, cultivation, and ecological climate. It compares cacao epiphytes observations in Nigeria to the general ecology of cacao cultivation in the said island. The article is also supplemented with information about geography, climate, parasitic and epiphytic plants, and the effect of rainfall to the cacao.