Radiation Conditions in the Territory of the USSR in Various Geological Periods

The components of the radiation balance and the heat balance are computed for Lat. 45°, 60° and 75°N for various geological periods. Cloud cover is estimated for each geological period on the basis of continentality, the character of the underlying surface, type of climate and landscape as well as the known mean magnitude during the present geological period. Albedo is based on the character of the underlying surface indicated by paleogeographic data. Effective outgoing radiation is also based on the character of the underlying surface as well as cloud cover and atmospheric moisture. The disposition of net radiation at the earth's surface is broken down into sensible and latent heat fluxes, the soil heat flux being ignored. The resulting mean data on radiation and heat-balance components are then used to reconstruct the probable range of climatic situations that may have existed in what are now the polar, middle, and subtropical latitudes of the territory of the USSR.     

General Circulation of the Atmosphere as an Essential Link in the System: Sun—Climatic Change

The author reviews the work done by himself and by Bezrukova-and Rubashev at the Pulkovo Observatory in relating fluctuations in the characteristics of the general circulation of the earth's atmosphere over the Northern Hemisphere to fluctuations in solar activity, on the one hand, and to climatic fluctuations, on the other. The general circulation of the atmosphere is thus found to meet the requirements of an intermediate link in the research system: sun—climatic change. This paper was read at the New York conference on solar variations, climatic change and related geophysical problems in January 1961.     

Atmospheric transparency variations associated with geomagnetic disturbances

Geomagnetic storm-time variations of the atmospheric transparency in various latitudinal regions are considered. It is shown that the solar radiation measured at the Earth's surface at local noon increases by approximately 0.1 cal/cm² min at latitudes ϑ = 60–70° during geomagnetic disturbances. At middle latitudes (ϑ≈ 50°) this effect is not observed. The variation of the atmospheric transparency is shown to be associated with a simultaneous decrease of the galactic cosmic ray intensity.     

Geographic Zonality and Polar Asymmetry

The author disagrees with Markov's suggestion that polar asymmetry, as a structural element of the earth's geographic envelope, takes precedence over geographic zonality. Sochava proposes instead that asymmetry be regarded merely as an additional characteristic of zonality).     

The Landscape Levels of Continents and Geographical Zonality

The traditional two-dimensional concept of latitudinal natural geographical zones is challenged on the ground that it ignores the altitude factor and differences in the character of the surface environment. An alternative three-dimensional model of zonal systems is proposed, in which so-called landscape levels corresponding to particular geomorphic levels are distinguished in terms of radiation balance and elevation. The zonal systems are combined into four worldwide groupings: (1) an inner terrestrial group corresponding to a rocky surface environment; (2) an outer terrestrial group corresponding to a cryogenic rocky environment; (3) an outer ice group, corresponding to ice-covered segments of the earth's surface, and (4) an oceanic group. The paper is devoted to the first three continental groups of zonal systems. The traditional zonality is found to be well expressed in the inner terrestrial group, but the outer groups reflect mainly Markov's law of polar asymmetry (see Soviet Geography, February 1964).     

A System of Natural Areal Complexes of the Earth

The tiered vertical structure of all the earth's landscapes is used as the basis for a typological classification of all natural areal complexes. Four basic landscape divisions are proposed: (1) terrestrial landscapes, consisting of an upper aerial layer and lower mineral layer, (2) aquatic landscapes, consisting of three tiers: air, water, mineral base, (3) glacial landscapes, consisting of three tiers (air, ice, mineral) on land, and of four tiers (air, ice, water, mineral) in oceans, (4) variable landscapes distinguished by a periodic succession of structures (terrestrial-aquatic, terrestrial-glacial, aquatic-glacial).     

LIMITATIONS OF USING A COARSE RESOLUTION MODEL TO ASSESS THE IMPACT OF CLIMATE CHANGE ON SEA ICE IN HUDSON BAY

The simulation of Sea-ice in a coarse resolution ocean general circulation model is examined in Hudson Bay and surrounding waters. Sea-ice distribution and duration compared well to climatological values, although ice thickness is undersimulated as it is in other modelling work. In Hudson Bay ice thickness variation was dominated by the atmospheric forcing as shown by the symmetric response of ice thickness to warming and cooling scenarios. Below ice heat fluxes play a more significant role in Foxe Basin and Baffin Bay where they mitigate air-ice heat loss by as much as 40 percent, thus limiting ice thickness and duration. Below ice heat flux reduces by 23 percent for the region of study (Hudson Bay, Foxe Basin, Baffin Bay, and Labrador Sea) for a global 3°C cooling and increases by 9 percent for a 3°C global warming. This asymmetric response is attributed to the ocean's asymmetric response to warming and cooling scenarios. In so much as Hudson Bay is dominated by atmospheric forcing rather than under ice heat as these results indicate, coarse resolution models may be useful in assessing the impact of change. However the necessary reconfiguration of the model grid render results from Foxe Basin and Hudson Strait less credible. On étudie la simulation de glace marine dans un modèle de circulation océanique générale à faible résolution dans la baie d'Hudson et dans les eaux avoisinantes. La distribution et la durée de la glace marine correspondent bien aux valeurs climatologiques, bien que l'épaisseur de la glace soit sous-simulée comme c'est le cas dans d'autres travaux de modélisation. Dans la baie d'Hudson, la variation de l'epaisseur de la glace est dominée par le forçage atmosphérique, comme on peut le voir d'après la réponse symétrique de l'épaisseur de la glace suivant les scénarios de réchauffement et de refroidissement. Les flux de chaleur sous la glace jouent un rôle plus important dans le bassin de Foxe et la baie Baffin, où ils permettent une réduction des pertes de chaleur air-glace allant jusqu'à 40 pour cent, limitant ainsi l'épaisseur de la glace et la durée. Le flux de chaleur sous la glace diminue de 23 pour cent dans la région étudiée (baie d'Hudson, bassin de Foxe, baie Baffin et mer du Labrador) pour un refroidissement global de 3C et augmente de 9 pour cent pour un réchauffement global de 3C. On attribue cette réponse asymétrique à la réponse asymétrique de l'océan aux scénarios de refroidissement et de réchauffement. Dans la mesure où, comme l'indiquent ces résultats, la baie d'Hudson est dominée par le forçage atmosphérique plutôt que par la chaleur sous la glace, des modèles à faible résolution peuvent être utiles pour évaluer l'impact des changements. Cependant, la reconfiguration nécessaire de la grille du modèle atténue la crédibilité des résultats obtenus dans le Bassin de Foxe et le détroit d'Hudson.     

The Development of General Earth Science in the USSR During the Soviet Period

General earth science, or general physical geography, is viewed as one of three synthetic physical-geographic disciplines, the two others being landscape science, or regional physical geography, and paleo-geography. General earth science is concerned with the earth's geographic or landscape envelope as a whole and with its general patterns: the laws of zonality and integrity of the landscape envelope, the circulation of matter, rhythmicity, polar asymmetry and other regularities.     

Tree-ring based temperature reconstruction for the west Qinling Mountains (China): linkages to the High Asia,solar activity and Pacific-Atlantic Ocean

We developed a Faxon fir (Abies faxoniana) tree-ring width chronology at the timberline in the western Qinling Mountains, China. Herein February–July mean temperature was reconstructed for Zhouqu in the western Qinling Mountains back to AD 1650 based on the standard chronology. The climate/tree-growth model accounts for 43.5% of the instrumental temperature variance during the period 1972–2006. Spatial correlation analyses with the gridded temperature data shows that the temperature reconstruction captures regional climatic variations over central and southeast China, and strong teleconnections with the nearby High Asia. There is a good agreement with cold and warm periods previously estimated from tree-rings in Nepal, India and southwest China. The temperature re-construction indicates that there was pronounced cooling in Zhouqu during the Maunder Minimum (late 1600s to early 1700s). The cold period (1813–1827) of the temperature reconstruction coincide with the volcanic eruptions. Significant spectral peaks are found at 56.9, 22.3, 11.4, 2.9, 2.8, 2.6, 2.2 and 2.0 years. The spatial correlation patterns between our temperature reconstruction and SSTs of the Atlantic and Pacific Oceans suggest a connection between regional temperature variations and the atmospheric circulations. It is thus revealed that the chronology has enough potential to reconstruct the climatic variability further into the past.     

LIVING MATTER AND TERRESTRIAL GLACIATION

Paleogeographic reconstructions and forecasts of climatic change have been based largely on the impact of cosmic and astronomic factors and have tended to ignore the impact of the geochemical activity of living organisms. Yet the CO₂ cycle in the biosphere (volcanic emissions on the income side and photosynthesis and burial of dead organic matter on the outgo side) can have a significant impact on climatic change because of the greenhouse effect. The CO₂ theory is used to explain the sequence of glacial and interglacial stages of the Pleistocene. Active volcanism during the Alpine mountain-building period resulted in a high CO₂ content in the atmosphere fostering the building up of a large phytomass. The continued absorption of CO₂ produced a cooling trend that led to the Ice Age. The spread of the ice sheet reduced the terrestrial biomass and thus the rate of CO₂ absorption, resulting in an increase of CO₂ in the atmosphere and a warming trend. In the interglacial stage that followed, the build-up of biomass again reduced atmospheric CO₂, producing a new cooling trend. This natural glacial-interglacial rhythm has been modified in the last 5,000 years by human activity. Maninduced reduction of phytomass (through deforestation) and, more recently, the intensive combustion of fossil fuels tend to increase the CO₂ content of the atmosphere (in contrast to the natural interglacial process) and make the advent of a new glacial stage unlikely. (The article was contributed by Victor L. Mote, University of Houston.)     

On a “Structural” and “Climatic” Geomorphology and a Critique of Certain Concepts

The separation of geomorphology into structural and climatic disciplines is challenged. Climate, rock properties, physical processes, and geological structure are considered to be so intimately intertwined in their effect on the formation of landforms that little basis is seen for a division of the discipline into climatogenetic and structural approaches. Contrary to Lester King's view, this does not mean that climate is not a significant factor. It must unquestionably be taken into consideration and be reflected in any genetic classification of landforms. There is no doubt, for example, that pediments, though likely to occur under a variety of climatic conditions, do find their most widespread development in Africa because of a combination of favorable climatic and structural conditions (arid or semiarid climate, the compliability of rocks to weathering, and the long duration of the cycle under shield conditions undisturbed by any significant tectonic uplifting).     

Screening Climatic and Non‐Climatic Risks to Australian Catchments

Emerging and future climatic change across the Australian continent has been identified as a significant threat to the successful sustainable management of the nation's water resources. However, the impacts of climate change must be viewed within the context of past, present and future climatic variability and human agency. A qualitative screening‐level risk assessment was undertaken for Australia's 325 surface water management areas by aggregating a suite of six relevant risk indicators. Four indicators addressed the antecedent conditions upon which future climate change will act. These included 50‐year trends in rainfall, the status of surface and groundwater development, and catchment condition. Two indicators addressed future drivers of supply and demand; specifically, projected changes in runoff and population. The results indicate that the management challenges currently experienced in Australia's population centres and key agricultural areas such as the Murray‐Darling Basin are likely to increase in future decades. Furthermore, the geographic distribution of net risk, inclusive of multiple biophysical and socioeconomic drivers, is more extensive than is suggested by consideration of surface water development and availability alone. Comparison of at‐risk catchments with the spatial distribution of various social and environmental assets identified a high degree of overlap among catchment risk and human populations, water storages, irrigated agricultural land, and wetlands of international significance. This suggests that the catchments of the greatest value are also those judged to be at greatest risk. Though considerable work remains in evaluating the security of Australia's water resources to climatic and other stressors, this study provides a first‐order scheme for prioritising the risks to which catchments are exposed and an assessment of how some key drivers are likely to interact to drive risk.     

On the global atmospheric electrical circuit

A model of global atmospheric electric circuit has been developed, which incorporates the pollution due to aerosol particles of anthropogenic and volcanic origins and the ionization caused by the coronal discharges due to intense electric field beneath thunderclouds in the atmospheric layers close to the earth's surface. Also the effects of solar activity and of Stratospheric Aerosol Particles (SAP) on the parameters of the circuit have been studied. The global distribution of Aerosol Particles (AP) of man-made origin has been assumed on the basis of world population density and that of volcanic origin on the basis of global distribution of volcanic activities. The thunderstorms are assumed to be the current generators of the global circuit. The latitudinal, longitudinal and height variations of atmospheric conductivity have been calculated from the known variations of ionization caused by cosmic rays, the radio-active emanations and intense electric fields beneath thunderclouds (over continents), along with the assumed variation of AP concentration.On increasing the AP concentration over the northern hemisphere by about 5 times that of the southern hemisphere, the ionospheric potential increases to about 6% and electric field increases in non-mountainous regions more than that in the high mountain regions. A large increase in SAP serves to increase the global resistance while both global current and ionospheric potential decrease. However, for low SAP concentration, the ionospheric potential increases. The SAP affect the electrical structure of the stratosphere without much influencing the troposphere except in the volcanically active regions, where conductivity is low due to high AP concentration. The major influence on the global atmospheric electric circuit occurs in response to solar activity. In the absence of local effects, the calculated variation of ionospheric potential is 14%. However, in real atmosphere (where both local and global processes act simultaneously), the ionospheric potential is found to vary by only about 3%. This has little effect on the ground electrical properties where more than 30% of the variations have been found to be caused by the local effect.     

The Latest Approaches and Concepts in Geography

The article discusses the present state of knowledge of the basic components of the heat balance of the earth's surface (radiation balance, loss of heat to evaporation, turbulent heat exchange) and the distribution of these components in time and space. Soviet research is concerned with applying heat-balance data to the study of physical-geographical processes (hydrologic regime, plant and soil cover), to the study of integrated geographic problems (geographic zonality) and practical problems (weather and hydrologic forecasting, the use of solar energy for productive purposes, and the use of heat-balance data for planning reclamation projects and other nature-transforming measures.)     

The Impact of Economic Activity on Climate

The effect of human activity on climate is examined against the background of a rapid increase in the production of man-made heat, which is likely to reach a magnitude of the order of the natural radiation balance on the earth's surface. The microclimate of cities is particularly affected by the production of industrial heat and by the heating of buildings in winter. Deforestation of large areas in conjunction with the expansion of agriculture has an impact on climate. The impact of shelterbelts is analyzed in detail, together with the effect of irrigation, swamp drainage and the creation of large reservoirs.     

Some Conclusions about the Geography of Cities and the Urban Population of the USSR based on the Results of the 1959 Census

The author acknowledges that climatic factors and man's activity are the principal causes of fluctuations in the level of the Caspian Sea. But he maintains that tectonic processes, such as crustal movements, play a significant part and gives evidence of correlations between geological processes and changes in the sea level.     

The Ecology of Command: U.S. Pacific Command and the Environment of the Pacific Rim

Abstract

Environmental ethicists speak fervently about the impact of human activity on the sustainability and survivability of Earth's community. But often these discussions fail to acknowledge one human activity more powerful and with the potential for greater destruction than any other— the United States military and its "empire of bases" encircling the globe. Military operations, both peacetime missions and contingency operations, and military installations stamp a large footprint on the earth's environment. From the atmospheric nuclear tests in the Bikini Atoll to the removal of the coral reef at Diego Garcia, the environment of the Pacific Rim has been shaped by the demands of U.S. national security. This paper examines the environmental footprint of U.S. Pacific Command. Secondly, it suggests that the exigencies of U.S. military presence need to be included in discussions of environmental ethics.     

On the influence of climatic factors on the ratio between the cosmogenic isotope 14C and total carbon in the atmosphere in the past

Radiocarbon ¹⁴C is a cosmogenic isotope, which is most extensively used by scientists from a wide variety of fields. Its rate of generation in the atmosphere depends on solar modulation and thus, studying ¹⁴C concentration in natural archives, one can reconstruct solar activity level in the past. The paper shows results of box-model calculations of generation of the ¹⁴C isotope in the atmosphere and its relative abundance during the time interval 1389–1800 AD, taking into account influence of changing climate. This interval includes the deep minimum of solar activity and period of significant change in atmospheric concentration of CO₂ and global temperature. The performed analysis showed that concentration of ¹⁴C in the atmosphere reflects not only variations of the galactic cosmic rays intensity but as well changes of temperature and atmospheric CO₂ concentration. It is shown that the decrease in CO₂ concentration in the atmosphere during 1550–1600 can be connected with absorption of CO₂ by the ocean surface layer. Thus, taking into account the climatic changes is an important condition for the reconstruction of solar activity in the past using data based on cosmogenic isotopes.     

On Natural Aquatic Complexes of the World's Oceans

The author, an exponent of the Soviet landscape school, proceeds from the assumption that the earth's natural environment is organized in terms of natural complexes that need to be identified and delimited. Landscape geographers have thus far focused on terrestrial landscapes, which occupy only 29% of the earth's surface. There is equal need for analysis of natural aquatic complexes, accounting for the remaining 71%. Aquatic complexes cannot be characterized only in terms of the sea surface; they must be analyzed in terms of the underlying water masses and their physical-chemical characteristics and organisms. Geographers working in this new branch of natural geography would require appropriate training.