Showing papers on "Climate change published in 1978"

Internally and externally caused climate change

Abstract: A numerical climate model is used to simulate climate change forced only by random fluctuations of the atmospheric heat transport. This short-term natural variability of the atmosphere is shown to be a possible 'cause' not only of the variability of the annual world average temperature about its mean, but also long-term excursions from the mean. Various external causes of climate change are also tested with the model and the results compared with observations for the past 100 years. Volcanic dust is shown to have been an important cause of climate change, while the effects of sunspot-related solar constant variation and anthropogenic forcing are not evident.

Biosphere-Albedo Feedback and Climate Modeling

Abstract: It is suggested that vegetational modification of the earth’s surface albedo, a process which occurs during a change in global climate, could produce a significant albedo-climate coupling or feedback mechanism. Employing the ice age of 18 000 years ago as a comparative climate, it is estimated that such a long-term biosphere-albedo feedback might roughly double the sensitivity of the global climate to factors which produce climatic change.

Changes in the global carbon cycle and the biosphere

Abstract: Increases in atmospheric CO/sub 2/, risks of climatic change, and impacts from such change are reviewed. Needs for closer scrutiny of changes in organic carbon and in the patterns of the biosphere are explained. The organic carbon pool is considered here as a moderate source of CO/sub 2/, perhaps 1 to 3 Gtons/yr in recent years. The biosphere could become a net sink for CO/sub 2/ if it were managed optimally to minimize the future peak of atmospheric CO/sub 2/ and to maximize storage as well as production rates of organic carbon. A preliminary global computer model explores the implications of tropical and subtropical forest clearing as a nonfossil source of CO/sub 2/ as well as some limits on the biosphere's role as a potential sink. Because of these limits and the oceanic factors of carbonate buffering, slow physical circulation, and limited net sedimentation of carbon, models confirm that 4- to 7-fold increases of CO/sub 2/ could occur if projections of high fossil energy consumption were to materialize. Review of climatic changes does not support beliefs that cooling would become great enough to counteract the mean surface temperature rise of 2 to 9/sup 0/C in 100 years. Changes in climatemore » pattern, temperature, drought, and waterlevel, and in their varied biological effects, would interact to change success of crops, other ecosystems, and many social institutions.« less

An explosive volcanic eruption in the Southern Hemisphere in 1928

Abstract: SEVERAL climatologists1–3 have compiled lists of volcanic eruptions which are thought to be of meteorological and climatological importance. Although these lists have been criticised for being incomplete4, subsequent authors5,6 have used them in studies designed to reproduce and explain the climatic history of the Northern Hemisphere. I report here additional information on two volcanic eruptions which may be climatologically significant but have generally not been considered in climate studies. By clarifying the volcanic chronology, a better test of the hypothesis that volcanoes cause part of the observed climate change can be made.

What might man-induced climate change mean

Abstract: The impacts of global climatic change are examined and the conclusion reached that an international multi-disciplinary effort is needed to reach understanding and a global consensus More research is needed to assess the short- and long-range effects of climatic shifts on agriculture and animals and the effects of both on social and political institutions Current information on carbon dioxide (CO/sub 2/) effects can be compared with past observations and used in climatic-simulation models to project future effects and illustrate their wide distribution Besides CO/sub 2/, heat emission and particulate matter released by fossil fuel and nuclear power plants are felt to have measurable impact Technological solutions will be helpful, but the need for serious social and economic adjustments is foreseen

Meteorological aspects of the 1975–76 drought

Abstract: The broad scale meteorological features are examined and it is shown that the drought is related to a variety of factors, including unusual coldness in the North Pacific ocean and over Canada in the winter half-year, upper winds stronger than usual in the Central Pacific, and the quasi-biennial oscillation. Feedback mechanisms involving Atlantic sea temperatures and the drought itself helped to maintain the atmospheric mode. The additional evaporation from a reservoir in Southern England due to extra sunshine, high summer temperature, etc., is estimated. An attempt is made to put the drought into historical perspective, with the conclusion that it appears to be a rare event rather than a symptom of climatic change. Lastly, by using a Meteorological Office general circu­lation numerical model, it is shown that a large area of dry ground may inhibit rainfall: the dryness of the ground over Western Europe in the 1976 summer may have had this effect.

Volcanic dust influence on glacier mass balance at high latitudes

Abstract: EXPLOSIVE eruptions, which inject large quantities of volcanic dust into the earth's upper atmosphere, are believed to be important factors in climatic change. Theoretical considerations suggest that the greatest climatic effect of a stratospheric dust veil would be at high latitudes during summer months, when solar radiation passes through the greatest depth of atmosphere and the surface is illuminated continously1. Furthermore, the residence time of volcanic dust is greatest at high latitudes, where it may remain in the upper atmosphere for a decade or more, depending on particle size and initial injection height2. Here we present evidence that the eruption of Mount Agung (8 °S, 115 °E) in March 1963, was responsible for a marked change in the climate of the North American High Arctic and that this change has had a significant impact on glacier mass balance in the region.

Is mankind warming the Earth

Abstract: Technical feature:Ways in which human activity affect climate changes are examined. The release of radioactive krypton-85 from nuclear reactors and fuel reprocessing plants, release of aerosols, and release of heat through thermal pollution are all major influences on climate. The buildup of carbon dioxide from fossil fuel combustion is the largest single factor that contributes to warming trends in climate. By the end of the century, the earth's average surface temperature will be warmer than at any time in the past 1000 years or more and will still be rising. The implications of a warmer earth and the effect warmer climate will have on ice masses are discussed. (1 diagram, 1 graph, 1 map, 1 photo, 21 references, 1 table)

Ocean Deserts and Ocean Oases

Abstract: Desertification can be a particularly visible consequence of climatic change. While considerable research has been devoted to terrestrial desertification in recent years, it is in the sea that biological deserts comprise 90% of the total area. Productive ocean ‘oases’ or coastal upwelling areas comprise less than .1% of the total ocean area but yield up to half the world's fish catch. Since these high productivity zones occur near coastal margins they are closest to man's pollution and his tools for species decimation. In this paper we examine the notion of biological deserts in the sea and assess the limitation of the ocean as a biological resource. Since climatic conditions favorable for above average ocean productivity are often conducive to the creation of coastal deserts, the connections between ocean and atmosphere in these regions are examined. Finally, the impacts of natural climatic and biological variability, marine pollution, and over-fishing on the process of biological desertification in the sea are explored.

Mechanisms and models of climatic change

Abstract: Many theories about climate change are essentially untestable, but we can still develop a consistent model based on understandable physics—in fact the data cannot be interpreted without one. Shutts and Green believe that there is some fundamental defect in all present models: it could be something physically improbable, like an unreasonable effect of tiny solar variations. More likely there is a fundamental lack in our appreciation of how very interactive systems behave.

Global Air Pollution and Climate Change

Abstract: Mankind has now demonstrated that it can change the composition of the atmosphere on a global scale. Those consequences of global air pollution which may have the greatest impact on society in the decades ahead are the associated changes in the radiation balance of the earth and atmosphere and the resulting change of climate. Carbon dioxide increase from the burning of fossil fuels at a continuingly increasing rate can cause a 1°C rise in mean surface temperatures by 2000 A.D., and 2-3°C rise by the middle of the next century. There are uncertainties in this projection of mean temperature rise of perhaps a factor of two; and the polar regions are expected to experience an increase several times larger. Other anthropogenic influences, such as the addition to the atmosphere of chlorofluoromethanes, nitrous oxide, and possibly aerosols, may contribute still further to this global warming. The mean surface temperature of the earth by 2000 A. D., if our projection is correct, will be warmer than at any time in the past 1000 years or more. Accompanying such a climate change there will be shifts in the large scale atmospheric circulation patterns and significant alterations of regional temperature and precipitation distributions-favorable for some regions, unfavorable for others, although we cannot predict the details of these changes.

Numerical simulation of climate and climatic change

Abstract: Detailed three-dimensional numerical models of the atmosphere, coupled as necessary to models of other parts of the climatic system, provide the most promising approach to understanding the physical basis of climate. Models of this kind can be used to investigate the impact of anthropogenic pollution on climate. At the present time, the main concern is with increasing concentrations of CO2 which might lead to overall warming of the troposphere, but chemical and thermal pollution may also pose a threat. The possible climatic changes would take place slowly and would involve the response of the slowly reacting parts of the climatic system, particularly the oceans. The problem of how to simulate such changes of climate presents many difficulties, which are currently being studied.

Climatic Change: Volcanoes, Man-Made Pollution, and Carbon Dioxide

Abstract: The causes of climatic change are summarized with emphasis on what appear to be the three most important factors external to atmospheric processes controlling climate on the scale of decades. These are 1) high level stratospheric particles injected by volcanic eruptions, 2) the increase in carbon dioxide due to an increase in industrial activity, and 3) generation of lower atmospheric particles directly caused by man. A historical perspective on each of these begins with the earliest discoveries and ends with current state of the art knowledge. The impact of these factors on climate is examined using the model of Bryson and Dittberner [30]. Results show that these three factors can indeed simulate, remarkably well, the past behavior of hemispheric climate as best we know it. The most important implication to emerge from this study is that climate is affected not only by nature, but also by man through the burning of fossil fuels and the subsequent production of carbon dioxide and particulates.

Water resources and climatic change

Abstract: Technical feature:Climate changes are induced by the natural influences or fluctuations in the output of the sun, interaction between the atmosphere and the ocean, and, possibly, sunspot activity or volcanic eruptions. However, human activity, such as pollution and alteration of the earth's surface, has changed the complex balance that governs climate. Significantly, human activities also affect water supply, which is inextricably linked to climate. The possible influences that human activity on water resources has on climate changes are studied. Other human activities that influence climate include: high energy consumption, which alters global temperature; and the destruction of vegetation, which affects the amount of solar energy absorbed. (1 drawing, 1 map, 2 photos)

Man and Climate: An Overview

Abstract: The possibility that human activities are affecting climate on a regional or global scale has been studied with increasing diligence during the past 20 years. Monitoring programs have been started and expanded, and mathematical models of climatic change, ofever increasing complexity, have been developed as computer capability has increased. Examination of all published information shows that the atmospheric carbon-dioxide content has increased by about 3 percent between 1958 and 1975 as a result of fossil-fuel combustion, that the solid-particle loading of the atmosphere has risen noticeably downwind of large urbanindustrial complexes in developed countries, although volcanoes and wind still provide nearly all the dust loading on a global scale, and that waste heat from man's activities now amounts to about 0.016 percent, or 1 part in 6000, of the average input of solar energy to the planet. Human influences are felt most strongly in and downwind of cities; in such areas the mean temperatures are higher, the mean diurnal temperature range is smaller, and the annual precipitation is higher than they would be were the cities absent. The urban influence is felt for only tens or a few hundred kilometers from these source regions.