Showing papers on "Climate change published in 1985"
Book•
01 Jan 1985
TL;DR: The paper as discussed by the authors presents the papers given at a conference on the atmospheric chemistry of carbon dioxide, including the carbon cycle, tropospheric methane cycle, the last deglaciation, reef growth, climatic change, carbon deposition rates in the Atlantic Ocean, low-latitude biomass, carbon isotopes, geochemistry, charcoal fluxes, volcanism, geologic ages, tectonics, carbonate rocks, marine surveys, and biogeochemistry.
Abstract: This book presents the papers given at a conference on the atmospheric chemistry of carbon dioxide. Topics considered at the conference included the carbon cycle, the tropospheric methane cycle, the last deglaciation, reef growth, climatic change, carbon deposition rates in the Atlantic Ocean, low-latitude biomass, carbon isotopes, geochemistry, charcoal fluxes, volcanism, geologic ages, tectonics, carbonate rocks, marine surveys, and biogeochemistry.
1,201 citations
TL;DR: In this article, the climate record obtained from two long Greenland ice cores reveals several brief climate oscillations during glacial time and suggests that these oscillations are caused by fluctuations in the formation rate of deep water in the northern Atlantic.
Abstract: The climate record obtained from two long Greenland ice cores reveals several brief climate oscillations during glacial time The most recent of these oscillations, also found in continental pollen records, has greatest impact in the area under the meteorological influence of the northern Atlantic, but none in the United States This suggests that these oscillations are caused by fluctuations in the formation rate of deep water in the northern Atlantic As the present production of deep water in this area is driven by an excess of evaporation over precipitation and continental runoff, atmospheric water transport may be an important element in climate change Changes in the production rate of deep water in this sector of the ocean may push the climate system from one quasi-stable mode of operation to another
1,049 citations
TL;DR: In this article, a world map of the Holdridge Life Zone Classification, developed from approximately 8,000 meteorological records, is compared with a Holdridge Map with average temperature increments simulated by a model of climate under elevated atmospheric CO2 concentration.
Abstract: The broad-scale distribution of terrestrial ecosystem complexes is determined in large part by climate and can be altered by climatic change due to natural causes or due to human activities such as those leading to increasing atmospheric CO2 concentration. Classifications that recognize the dependence of natural vegetation on climate provide one means of constructing maps to display the impact of climatic change on the geography of major vegetation zones. A world map of the Holdridge Life-Zone Classification, developed from approximately 8,000 meteorological records, is compared with a Holdridge Map with average temperature increments simulated by a. model of climate under elevated atmospheric CO2 concentration. The largest changes are indicated at high latitudes, where the simulated temperature increase is largest and the temperature intervals defining life zones are smallest. Boreal Forest Zones are replaced by either Cool Temperate Forest or Cool Temperate Steppe, depending on average precipitation. Changes in the tropics are smaller; however, in some regions, Subtropical Moist Forest is replaced by Tropical Dry Forest.
593 citations
01 Dec 1985
TL;DR: In this article, what is known about detecting the CO2-induced changes in climate, and describes the uncertainties and unknowns associated with this monitoring and analysis effort are discussed, followed by a review of applications of these strategies to the various climatic variables that are expected to be changing.
Abstract: This report documents what is known about detecting the CO2-induced changes in climate, and describes the uncertainties and unknowns associated with this monitoring and analysis effort. The various approaches for detecting CO2-induced climate changes are discussed first, followed by a review of applications of these strategies to the various climatic variables that are expected to be changing. Recommendations are presented for research and analysis activities. Separate abstracts have been prepared for the individual papers. (ACR)
193 citations
TL;DR: In this paper, a hierarchy of explanatory models is employed, including a statistical model that uses gain and phase terms to parameterize the climatic response to orbital forcing in several narrow frequency bands.
Abstract: This paper reviews 150 years of progress towards understanding the succession of Pleistocene ice ages. Emphasis is placed on the process of explaining forced variations in climate which occur in the Milankovitch band (periods from 10000 to 400 000 years), where astronomical forcing functions are clearly identified and where the amplitudes of climatic change are large. An hierarchy of explanatory models is employed, including a statistical model that uses gain and phase terms to parameterize the climatic response to orbital forcing in several narrow frequency bands. This type of model accounts for a substantial fraction of the observed temporal variations of δ 18 O over the past 800 000 years. Experiments using the model suggest that a change in the system response occurred about 400 000 years ago. The problem of explaining climatic variations in other frequency bands is briefly reviewed. In the decadal band (l0–400 years), there is good evidence of volcanic forcing, solar forcing, and tidal forcing, but much of the observed pattern is presumed to reflect free variations. In the millenium band (400 to 10 000 years), significant climatic changes occur at periods ranging from 1000 to 3000 years. Their cause remains a challenging problem. Over the tectonic band (more than 400 000 years), volcanic fluxes, continental elevation, and continental position are the most likely forcing functions of the observed climatic changes.
174 citations
TL;DR: In this article, an analysis of a ∼600-year response of a lichen-spruce woodland to the long-term trend in the Northern Hemisphere is presented, which is the first extensive illustration of these impacts in the Subarctic.
Abstract: The climate of the Northern Hemisphere changed during recent centuries, as shown by the Little Ice Age episode1 and the warming trend of the past 100 years2,3. The ecological impacts of these changes have yet to be evaluated in several terrestrial ecosystems, incorporating direct evidence such as detailed botanical field observations4. We report here results of the analysis of a ∼600-year response of a lichen–spruce woodland to this long-term trend, which are thought to be the first extensive illustration of these impacts in the Subarctic. It suggests that tree-line vegetation is in a dynamic equilibrium with climate in the absence of other external disturbances; this is emphasized by spruce reaction through phenotypic adaptation—a shift from stunted individuals (krummholz) to normal trees (forest)—and differential regeneration. This study produces evidence that marginal northern forests can persist through time and that successional processes, in the absence of fire, perpetuate the original lichen–spruce facies. The longest tree-ring chronology (AD 1398–1982) yet available in eastern North America was constructed from living and dead spruces found in the lichen woodland of our study.
153 citations
TL;DR: In this paper, the late Quaternary climate of the North Pacific was investigated, where according to modelling the solar radiation in the early Holocene at the time of the summer solstice is high and in the late Holocene is relatively low.
Abstract: The late Quaternary climate of the North Pacific, where according to modelling the solar radiation in the early Holocene at the time of the summer solstice is high and in the late Holocene is relatively low, is investigated. Quantitative temperature and precipitation estimates from southern Alaska are compared with estimates from western Washington and British Columbia. Data extending over more than 10,000 years show a broadly consistent pattern of climatic change in general agreement with predicted variations in solar radiation and their effect on atmospheric circulation and seasonal duration of pressure systems over the North Pacific Ocean. In the early Holocene, the subtropical North Pacific anticyclone annually regulated climate for a longer period at higher latitudes than at present, so that warmth and dryness increased in southern Alaska. The Aleutian low-pressure center intensified during the late Holocene, resulting in colder and more humid coastal climate and increased frequency of glacier growth in the cordillera.
144 citations
TL;DR: In this paper, the response of deep ocean circulation to major climatic events of the past 135,000 years is inferred using carbon-13 analyses of benthic foraminifera from the major ocean basins.
Abstract: The response of deep ocean circulation to major climatic events of the past 135,000 years is inferred using carbon-13 analyses of benthic foraminifera from the major ocean basins. The results demonstrate that the circulation of the world ocean deep water is very sensitive to climate and that it changes drastically during climatic transitions.
140 citations
TL;DR: The use of general circulation models in the estimation of the impact of climatic change on the global ecosystem is seen to depend primarily on their ability to reliably depict the seasonal and geographical distribution of the changes in surface climate variables as discussed by the authors.
Abstract: The use of general circulation models in the estimation of the impact of climatic change on the global ecosystem is seen to depend primarily on their ability to reliably depict the seasonal and geographical distribution of the changes in surface climate variables. While present GCMs generally simulate the observed distribution of surface air temperature reasonably well, they show significantly different changes in the equilibrium temperature as a result of doubled CO2, for example. These disagreements are attributed to differences in the model's resolution and parameterization of subgrid-scale processes. Such model-dependent errors notwithstanding, much more information of possible use in impact analysis can be extracted from general circulation model simulations than has generally been done so far. The completeness, consistency and experimental possibilities offered by simulated data sets permit the systematic extraction of a wide variety of statistics important to the surface ecosystem, such as the length of the growing season, the duration of rainless periods, and the surface moisture stress. Assuming further model improvements, the elements of a model-assisted methodology for climate impact analysis are seen to be: (1) the determination of the seasonal and geographical distribution of that portion of simulated climatic changes which are both statistically and physically significant; (2) the transformation of the (significant) large-scale climatic changes onto the local scale of impact (the climate ‘inversion’ problem); and (3) the design of specific statistical parameters or functions relevant to local ecosystem impacts.
109 citations
TL;DR: A series of General Circulation Model experiments are performed to examine the role of paleogeography as an explanation of the Tertiary global cooling trend as mentioned in this paper, but not a long-term Cenozoic trend.
102 citations
TL;DR: The authors used modern pollen and radiolarian distributions in sediments from the northwest Pacific and seas adjacent to Japan to interpret floral and faunal changes in core RC14-103 (44°02′N, 152°56′E).
TL;DR: In this article, an investigation is made of the possible impacts of a climatic change (induced by a doubling of atmospheric carbon dioxide concentration) on the European agricultural sector, and two general circulation models have been used to develop climate change scenarios for the European study area.
Abstract: An investigation is made of the possible impacts of a climatic change (induced by a doubling of atmospheric carbon dioxide concentration) on the European agricultural sector. Two general circulation models have been used to develop climatic change scenarios for the European study area. From the scenarios, information was obtained concerning the possible behavior of temperature, precipitation, solar radiation, and relative humidity in the altered climatic state. This meteorological information was then employed in two separate crop-weather models - an empirical/statistical model (for winter wheat) and a simple simulation model (for biomass potential). This type of approach represents a considerable departure from that employed by previous large-scale climate impact studies. Both the seasonal and regional components of a possible climatic change are incorporated directly in the two crop-weather models. The results of this investigation demonstrate that a simple crop-weather simulation model may be more suitable for the purposes of agricultural impact analysis than the linear regression models frequently used in such studies. In order for such an impact analysis to be accepted as a valid scientific experiment, a full presentation of the underlying assumptions and uncertainties is essential.
TL;DR: In this paper, a coupled global atmosphere-ocean general circulation model (GCM) has been used to investigate the role of the ocean in CO 2 -induced climate change, and two 16-year simulations have been made, a 1 X CO 2 simulation with a CO 2 concentration of 326 ppmv, and a 2 XCO 2 simulation of 652 ppmv.
TL;DR: The authors found that changes in winter climate patterns over North America and in the Walker Circulation over the tropical Pacific Ocean are linked to changes in the upper equatorial Pacific Ocean thermal energy pool.
Abstract: Short-term climate changes which take place in both the tropics and at mid-latitudes are strongly influenced by large-scale fluctuations in near-equatorial ocean sea surface temperatures and by attendant fluctuations in air-sea fluxes of heat and moisture. In particular, there is evidence that changes in winter climate patterns over North America and in the Walker Circulation over the tropical Pacific Ocean are linked to changes in the upper equatorial Pacific Ocean thermal energy pool. This pool evolves in response to both local and distant sources of heat. Locally, solar radiation heats the ocean, while evaporation, equatorial upwelling, and vertical mixing cool it.
TL;DR: In this paper, a remarkable climatological record exists in the heart of the North American interior that deserves recognition and exploitation and the objective of this paper is to bring this unique record that commenced in October, 1819, at Ft. Snelling, Minn., to the attention of the climate change community.
Abstract: A remarkable climatological record exists in the heart of the North American interior that deserves recognition and exploitation. The objective of this paper is to bring this unique record that commenced in October, 1819, at Ft. Snelling, Minn., to the attention of the climate change community.
TL;DR: For specific elements such as temperature or precipitation, a substantial portion of these changes can be shown to be statistically significant; that is, they either reflect an unusual combination of events in a stationary process or they reflect a nonstationary process as mentioned in this paper.
Abstract: The climate record from many parts of North America provides ample evidence of climate change. For specific elements such as temperature or precipitation, a substantial portion of these changes can be shown to be statistically significant; that is, they either reflect an unusual combination of events in a stationary process or they reflect a nonstationary process. The practical significance of a climate change, however, even when it can be shown to be statistically significant, cannot be assumed. Conversely, it is entirely possible to have a practically significant climate change without statistical significance, although this is less likely to occur. The preponderance of evidence over recent years suggests that any notion regarding static climate regimes must be dismissed in favor of a dynamic system. The differential heating of our planet which results in a restless atmosphere can also yield a restless climate. Whether this dynamic climate system is merely a manifestation of natural variations or at lea...
TL;DR: In this paper, a review of the current state of knowledge of these aspects of the CO2 issue prior to a discussion of the changes in climate that might be expected from increased levels of CO2, whenever these might occur is given.
Abstract: Two factors will determine the rate at which CO2 levels in the atmosphere increase in the future: the rate of input to the atmosphere, primarily from fossil fuel burning, and the way in which this CO2 is partitioned between atmosphere, ocean and biosphere. A brief review is given of the current state of knowledge of these aspects of the CO2 issue prior to a discussion of the changes in climate that might be expected from increased levels of CO2, whenever these might occur. The basis of climate modelling upon which our expectations rest is explained, indicating the nature of the uncertainty that currently exists in the model results. While some of the gross features of the likely climatic change seem reasonably well established qualitatively, considerable model development will be needed before reliable information on the likely regional effects is forthcoming. Observations have yet to confirm the occurrence of temperature change attributable to CO2 increases. Nevertheless, the possibility exists of a change in climate during the coming century that may be substantial relative to past experience. Although direct measures to control CO2 emissions would certainly be premature, long-term planning of infrastructures, closely tuned to present climatic conditions, should ensure their robustness in the face of the uncertain climatic changes that may lie ahead.
TL;DR: In this paper, two snow and ice cores from the Rennick Glacier area, Antarctica were analyzed for the chemical species: chloride, sodium, reactive silicate, sulfate and nitrate.
Abstract: Two snow and ice cores from the Rennick Glacier area, Antarctica (study area center point lat 71 ·15'S, long 162 ·30' E) were analyzed for the chemical species: chloride, sodium, reactive silicate, sulfate and nitrate . Core EIO (6.35 m) was taken from Evans Neve, a large accumulation basin at the head of Rennick Glacier. Core MI (4.35 m) was extracted from the accumulation zone on the central plateau of the Morozumi Range, a smal l mountain massif bordering Rennick Glacier. Cores EIO and MI span the time periods from 1929 to 1981 and from 1971 to 1981, respectively, as dated using seasonal variations in chloride (EI0) and sulfate (MI) concentrations . An estimated net balance of 50 kg m2 a-I was derived for site EI0 and of 182 kg m2 a-I for site Ml. The difference in net mass balance may be explained by elevational differences (MI 1400 m a.s.l., EIO 2305 m a.s.l .). Recent (1973 to 1980) increases in sodium, silicate and sulfate at site EIO may be linked to decreases in Antarctic pack-ice extent (Kukla and Gavin 1981) for
TL;DR: The global atmosphere is being enriched with carbon dioxide through the combustion of fossil fuels and reduction of forest biomass and soil organic matter as discussed by the authors, which will have direct impacts on the forest sector, probably favoring fast growing species, in particular certain hardwoods and weed species.
Abstract: The global atmosphere is being enriched with carbon dioxide through the combustion of fossil fuels and reduction of forest biomass and soil organic matter. The estimated preindustrial concentration of 260 parts per million by volume is expected to be doubled by the year 2065, with consequential disturbance in global and regional climates. Enrichment will certainly have direct impacts on the forest sector, probably favouring fast growing species, in particular certain hardwoods and weed species. An antitranspirant effect of CO2 may also improve growth rates and water economies, especially in arid regions. Impacts of climatic disturbance are much more difficult to predict, largely because of uncertainty in current climate response theory. Best available information indicates the development of a serious mismatch between Canadian forests and the climatic regions they will occupy. When viewed as empirical models of climate change, past climate variation suggest that forest pest problems will intensify. Operat...
TL;DR: In this paper, the authors examine a number of fundamental obstacles which will prevent fossil fuel use reductions or changes in deforestation activities, and argue that these moral and ethical issues are crucial for approaching the specific question of global climate change, but also the general class of environmental problems that will require international co-operation to resolve.
01 Jan 1985
TL;DR: In this article, an analysis of Miocene-aged Deep Sea Drilling Project cores reveals eight widespread hiatuses correspond to intervals of cooling as indicated by fauna and flora, 180 anomalies and low sea-levels.
Abstract: The Quaternary characterized by two climatic signatures: that of the last 800,000 years, the Upper Pleistocene Climatic Signature (UPCS), and that of the period from 900,000 to 1,800,000 years ago, the Middle Pleistocene Climatic Signature (MPCS). Glacial cycles within the UPCS are 100,000 years long containing interglacials of 10,000-12,000 years duration and a "full" glacial period of 20,000-30,000 years. Cycles of the MPCS range from 20,000-40,000 years duration. Analysis of Miocene-aged Deep Sea Drilling Project cores reveal eight widespread hiatuses. These hiatuses correspond to intervals of cooling as indicated by fauna and flora, 180 anomalies and low sea-levels. The Miocene hiatuses may result from decreased polar temperatures and concomitant increased bottom water circulation and corrosiveness. Durations represented by both hiatuses and preserved sediments are approximately one to two million years long. The inferred Miocene glacial epochs are of the same duration as the glacial epochs of the Plio-Pleistocene. Oligocene-aged hiatuses are found in all the world's oceans, indicative of cold bottom-following waters. Evidence (hiatuses, ice rafted material) has demonstrated Eocene continental glaciers in Antarctica. Interaction between the three planetary orbital parameters of eccentricity, tilt, and precession apparently control much of long-term climate change with the dominance of eccentricity dictating glacial cycles. Continuity of climate pattern for the Tertiary is indicated, given the constancy of planetary motion. Gulf Coast hydrocarbon reservoirs of Miocene, Frio, and Wilcox age should be reviewed in terms of a more subtle climatic model to refine interpretation of known depositional sequences.
01 May 1985
TL;DR: The state-of-the-art of mathematical models of transient climate change from historical and projected increases in atmospheric carbon dioxide and related factors is reviewed in this article, including studies done at NYU and elsewhere.
Abstract: The state-of-the-art of mathematical models of transient climate change from historical and projected increases in atmospheric carbon dioxide and related factors is reviewed, including studies done at NYU and elsewhere Major conclusions are: (1) the transient climate changes over 10 to 100 year timescales are probably driven by several ''external'' factors acting simultaneously, as well as ''internal'' factors such as variations in ocean dynamics; (2) the response of global temperature to this forcing is not instantaneous, but is delayed by times of the order 10 to 100 years by thermal damping by the upper ocean; (3) the development of reliable models is hampered by lack of a clear validation strategy for testing models against observations; (4) when run with standard scenarios, current models predict a global warming of the order of 1/sup 0/C by the year 2000 relative to 1850, with an additional 2 to 5/sup 0/C over the next century; However, the sensitivity of these predictions to uncertainties has not been sufficiently explored Specific research programs are recommended to improve our ability to predict transient climatic changes from continued fossil fuel burning
01 Dec 1985
TL;DR: In this article, the results of three-dimensional general circulation models (GCM) were used for the estimation of a potential climatic change induced by a doubling of atmospheric CO2.
Abstract: For the estimation of a potential climatic change induced by a doubling of atmospheric CO2 we use the results of three-dimensional general circulation models (GCM) Although the results from present climate modeling cannot be considered as predictions of future climatic conditions due to the inherent models' deficiencies, they can still serve a useful purpose in climate change scenarios The reason for this is that climate models are the only tools available to study the response of the climate system to a perturbation in a physically consistent manner and that such types of models can provide a consistent data set of high temporal and spatial resolution For the Mediterranean area, the results obtained from three different GCMs, namely, the British Meteorological Office model (BMO), the Goddard Institute for Space Studies model (GISS), and the National Center for Atmospheric Research model (NCAR) are shown The regional and seasonal distributions of temperature, precipitation, and soil moisture are used to study the potential changes The results indicate that the CO2-induced changes for temperature generated by the three models are of similar magnitude The values of the area mean change range between 25 and 40 K The precipitation response results in a diverse pattern The physical mechanism likely to be responsible for the simulated climatic changes are identified and their statistical significance is tested This type of work will help us develop the methodology and assist us in gaining insight into the use of climate model scenarios for impact analysis
01 Jan 1985
TL;DR: In this article, the ESA Symposium on Application of Satellite Data to Climate Modelling, Alpbach et al. discussed climate variations leading to changes in relative sea level with some emphasis on the possible effects of carbon dioxide warming.
Abstract: Review paper, ESA Symposium on Application of Satellite Data to Climate Modelling. Alpbach (Austria)
Sea level is an essential component of the climate
system, on which many human activities in the
coastal zone depend. Climate variations leading
to changes in relative sea level are discussed,
with some emphasis on the possible effects of a
carbon dioxide warming. Variations in land ice
volume are probably most important. Suggestions
are given of how future satellite data may help
in monitoring and understanding of global
variations in sea level.