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Introduction to Earth processes and global changes
Palaeogeography, Palaeoclimatology, Palaeoecology (Global and Planetary Change Section), 82 (1990): 1-3
1
Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands
Introduction to Earth Processes and Global Changes K E N N E T H J. HS£1 and W.U. H E N K E N - M E L L I E S Geological Institute, E.T.H. Zurich (Switzerland) (Received November 22, 1989)
The interactive physical, chemical and biological processes on Earth can be described as fluxes of matter and energy within and across the boundaries of the atmosphere, hydrosphere, lithosphere, and biosphere. The fluxes have been accelerated to significant extent that our society is becoming increasingly aware of global changes which are threatening our well being. For this reason, the International Council of Scientific Unions (ICSU) has initiated an International Geosphere and Biosphere Program (IGBP). The priority in this program has fallen on those areas that deal with key interactions and significant change on time scales of decades to centuries. It has been said that earth scientists are dealing with ancient rocks, and that they have little to contribute to studies of short-term global changes. Recognizing the relevance of geology to IGBP, the Executive Committee of the International Union of Geological Sciences (IUGS), in their February, 1988 meeting at Canton, China, constituted a Task Group on Global Changes, to explore the ways and means to contribute to the IGBP/Global Change of ICSU. The Task Group, chaired by the senior author, met at Samedan, Switzerland, in April, 1988 and decided that the efforts by the earth science community should be focused on the four following themes: (1) To document the marine and atmospheric records, particularly those of the last 105 years. (2) To document the terrestrial records, particularly those of the last 105 years. (3) To document the anthropogenically induced global changes, including depletion of nonrenewable resources. Elsevier Science Publishers B.V.
(4) To explore the consequences of reduction of bio-diversity, with reference to records of past catastrophes. A Workshop on Global Changes, Past and Present, sponsored by IUGS, UNESCO, Swiss Academy of Natural Sciences, and Swiss Federal Institute of Technology, was held at Interlaken, Switzerland, in April 1989, to discuss the implementation of the IUGS program. The workshop was organized in a pattern worked out by Silke Bernhard for Dahlem Conferences: Four working groups had been established to discuss the four themes. Each, except the WG .1, prepared position papers which were distributed to all participants prior to the meeting, so that the time at Interlaken could be be used for interdisciplinary discussion and for preparing final reports. This volume presents the working group reports and background papers of the Interlaken workshop. For the Ocean Record of Past Global Changes, the report of WG 1 (N. Shackleton, chairman; T.H. Van Andel, rapporteur) indicates that studies of the ocean-atmosphere system at different modes of operation in the past will help to identify where the man-made changes of the system are heading, including a knowledge of feed-back mechanisms, and of non-linear responses beyond certain threshold values. The group decided to integrate what might have been individual background papers into the text of the WG report, which consists of two parts: 1. Objectives related to a long time scale (105 years) and those related to intermediate and short time scales (10-104 years). On the long time scale, major problems include the extent and dynamics
2
of the ice cover, the formation of deep and intermediate water masses, the past record of atmospheric circulation, and the special regional conditions monitored in marginal basins. The problems of shorter time scales include studies of the cause of sudden climatic changes at the beginning and the end of the Younger Dryas, of "little ice ages", and predictions of the implications of anthropogenically induced changes during the next decades and centuries. The report of WG 2 is mainly a contribution by INQUA (the International Union of Quaternary Research) to the IUGS program; the chairman and rapporteur of the group are the President and General Secretary of INQUA, respectively. The different time scales are also recognized. As a means of synthesizing data into a global framework, the construction of global paleoenvironmental maps was endorsed. The identification of past and present sea-level changes was another major topic. WG 2 submitted seven short position papers. H. Faure discussed the changes in the global continental reservoir of carbon. B. Huntley summarized the contribution of Quaternary palynology to studying global change. D. Yaalon interpreted climatic changes on the basis of investigating soils and paleosols. Schnack and Pirazzoli reviewed Quaternary sea-level changes. C. Schluchter pointed out the implications of continental records, espedally that of the last glacial cycle. L. Starkel elucidated problems of paleohydrology on land. W . R . Peltier p r e s e n t e d a synopsis of paleoenvironmental modelling. The group report concluded by identifying a number of key projects of highest priority. The WG 3 (I. Thornton, chairman; H. ApSimon, rapporteur) filed a report of anthropogenically induced global change. The time scale under consideration seldom went beyond the past 2000 years. The discussions were centered on anthropogenic interaction with the environment and on the depletion of available resources (soil, groundwater) and degradation of coastal environment. The report is supplemented by four position papers. J.O. Nriagu called attention to the human influence on the global cycling of trace metals. I. Thornton re-
K.J. HSU AND W.U. HENKEN-MELLIES
viewed the present knowledge of soil contamination in urban areas. A.L. Page and E. Steinnes noted a source of trace elements in soils from atmospheric deposition. J.M. Pacyna and J.W. Winchester made observations on the contamination of the global environment in the arctic. The WG 4 report (D. McLaren, chairman: R.E. Ricklefs, rapporteur) assessed the extent of the present man-induced extinction event, and sought insight from the lessons of past extinctions. The most serious consequence is the irreversibility of the destruction of natural habitats and of species extinction. The background papers serve as a basis of the group's discussions at Interlaken. E. Buffetaut and N. Myers both wrote on the relevance of past mass extinctions to an understanding of the present and future processes of extinction. P.S. Martin told a horror story of 40,000 years of extinctions on the "planet of Doom." A. Traverse discussed plant evolution in relation to world crises, and saw a ray of hope in the apparent resilience of Kingdom Plantae. The Interlaken Workshop is not the conclusion, but the beginning of a concentrated effort by the community of earth scientists to problems of global change. A decision was made at Interlaken to recommend the initiation of a cooperative program between the IUGS and UNESCO to study Earth Processes and Global Changes. A resolution-proposal was introduced by the Swiss Delegation to the UNESCO's General Conference at Paris, October, 1989:
"The General Conference, 1. Being convinced that identifying and ameliorating global changes leading to environmental devastations and irreversible depletion of natural resources is one of the most urgent scientific problems of today, and that this problem can be solved only through multinational and interdisciplinary cooperation, 2. Considering that the development and progress of civilization on Earth will to a large extent be determined by the quality of the environment and by the capacity of nature to
INTRODUCTION
3.
4.
5.
6.
achieve stable biological reproduction in all its natural diversity, Noting that cooperation between the UNESCO and the scientific community represented by the International Union of Geological Sciences in form of the U N E S C O / IUGS International Geological Correlation Program (IGCP) has proved an effective model for multinational and interdisciplinary cooperation to tackle geological problems relevant to the well being of the civilization, Understanding that environmental protection, preservation of the ecological balance, and non-hazardous exploitation of non-renewable natural resources make up one of the most important of mankind's tasks for insuring quality of life for future generations, Realizing that evaluating global changes and their deleterous effects on mankind can be made more effective by establishing a longterm programme involving the cooperation between UNESCO and the international community of scientists, with reference to the existing IGCP model, Decides 1. To invite the Director-General to study
3
the feasibility of cooperating with the International Union of Geological Sciences and the International Council of Scientific Unions to initiate a program on Earth Processes and Global Changes, as a contribution by U N E S C O / I U G S to ICSU's International Geosphere Biosphere Program. 2. To allocate US$20,000 within the proposed budget for 1990/91 for initiating pilot projects on Earth Processes and Global Changes of immediate urgency, such as short-term climatic variations of the past, anthropogenically induced environmental changes, or mass extinction of species induced by global changes." After its approval by the General Conference, it is foreseen that an I U G S / U N E S C O program on Earth Processes and Global Changes will be set up, with an administrative structure similar to the I U G S / U N E S C O International Geological Correlation Program. The program could then support interdisciplinary field conferences on specific regional projects, to facilitate international exchanges of scientific data, methodology, samples, and of academic personnel.
1
Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands
Introduction to Earth Processes and Global Changes K E N N E T H J. HS£1 and W.U. H E N K E N - M E L L I E S Geological Institute, E.T.H. Zurich (Switzerland) (Received November 22, 1989)
The interactive physical, chemical and biological processes on Earth can be described as fluxes of matter and energy within and across the boundaries of the atmosphere, hydrosphere, lithosphere, and biosphere. The fluxes have been accelerated to significant extent that our society is becoming increasingly aware of global changes which are threatening our well being. For this reason, the International Council of Scientific Unions (ICSU) has initiated an International Geosphere and Biosphere Program (IGBP). The priority in this program has fallen on those areas that deal with key interactions and significant change on time scales of decades to centuries. It has been said that earth scientists are dealing with ancient rocks, and that they have little to contribute to studies of short-term global changes. Recognizing the relevance of geology to IGBP, the Executive Committee of the International Union of Geological Sciences (IUGS), in their February, 1988 meeting at Canton, China, constituted a Task Group on Global Changes, to explore the ways and means to contribute to the IGBP/Global Change of ICSU. The Task Group, chaired by the senior author, met at Samedan, Switzerland, in April, 1988 and decided that the efforts by the earth science community should be focused on the four following themes: (1) To document the marine and atmospheric records, particularly those of the last 105 years. (2) To document the terrestrial records, particularly those of the last 105 years. (3) To document the anthropogenically induced global changes, including depletion of nonrenewable resources. Elsevier Science Publishers B.V.
(4) To explore the consequences of reduction of bio-diversity, with reference to records of past catastrophes. A Workshop on Global Changes, Past and Present, sponsored by IUGS, UNESCO, Swiss Academy of Natural Sciences, and Swiss Federal Institute of Technology, was held at Interlaken, Switzerland, in April 1989, to discuss the implementation of the IUGS program. The workshop was organized in a pattern worked out by Silke Bernhard for Dahlem Conferences: Four working groups had been established to discuss the four themes. Each, except the WG .1, prepared position papers which were distributed to all participants prior to the meeting, so that the time at Interlaken could be be used for interdisciplinary discussion and for preparing final reports. This volume presents the working group reports and background papers of the Interlaken workshop. For the Ocean Record of Past Global Changes, the report of WG 1 (N. Shackleton, chairman; T.H. Van Andel, rapporteur) indicates that studies of the ocean-atmosphere system at different modes of operation in the past will help to identify where the man-made changes of the system are heading, including a knowledge of feed-back mechanisms, and of non-linear responses beyond certain threshold values. The group decided to integrate what might have been individual background papers into the text of the WG report, which consists of two parts: 1. Objectives related to a long time scale (105 years) and those related to intermediate and short time scales (10-104 years). On the long time scale, major problems include the extent and dynamics
2
of the ice cover, the formation of deep and intermediate water masses, the past record of atmospheric circulation, and the special regional conditions monitored in marginal basins. The problems of shorter time scales include studies of the cause of sudden climatic changes at the beginning and the end of the Younger Dryas, of "little ice ages", and predictions of the implications of anthropogenically induced changes during the next decades and centuries. The report of WG 2 is mainly a contribution by INQUA (the International Union of Quaternary Research) to the IUGS program; the chairman and rapporteur of the group are the President and General Secretary of INQUA, respectively. The different time scales are also recognized. As a means of synthesizing data into a global framework, the construction of global paleoenvironmental maps was endorsed. The identification of past and present sea-level changes was another major topic. WG 2 submitted seven short position papers. H. Faure discussed the changes in the global continental reservoir of carbon. B. Huntley summarized the contribution of Quaternary palynology to studying global change. D. Yaalon interpreted climatic changes on the basis of investigating soils and paleosols. Schnack and Pirazzoli reviewed Quaternary sea-level changes. C. Schluchter pointed out the implications of continental records, espedally that of the last glacial cycle. L. Starkel elucidated problems of paleohydrology on land. W . R . Peltier p r e s e n t e d a synopsis of paleoenvironmental modelling. The group report concluded by identifying a number of key projects of highest priority. The WG 3 (I. Thornton, chairman; H. ApSimon, rapporteur) filed a report of anthropogenically induced global change. The time scale under consideration seldom went beyond the past 2000 years. The discussions were centered on anthropogenic interaction with the environment and on the depletion of available resources (soil, groundwater) and degradation of coastal environment. The report is supplemented by four position papers. J.O. Nriagu called attention to the human influence on the global cycling of trace metals. I. Thornton re-
K.J. HSU AND W.U. HENKEN-MELLIES
viewed the present knowledge of soil contamination in urban areas. A.L. Page and E. Steinnes noted a source of trace elements in soils from atmospheric deposition. J.M. Pacyna and J.W. Winchester made observations on the contamination of the global environment in the arctic. The WG 4 report (D. McLaren, chairman: R.E. Ricklefs, rapporteur) assessed the extent of the present man-induced extinction event, and sought insight from the lessons of past extinctions. The most serious consequence is the irreversibility of the destruction of natural habitats and of species extinction. The background papers serve as a basis of the group's discussions at Interlaken. E. Buffetaut and N. Myers both wrote on the relevance of past mass extinctions to an understanding of the present and future processes of extinction. P.S. Martin told a horror story of 40,000 years of extinctions on the "planet of Doom." A. Traverse discussed plant evolution in relation to world crises, and saw a ray of hope in the apparent resilience of Kingdom Plantae. The Interlaken Workshop is not the conclusion, but the beginning of a concentrated effort by the community of earth scientists to problems of global change. A decision was made at Interlaken to recommend the initiation of a cooperative program between the IUGS and UNESCO to study Earth Processes and Global Changes. A resolution-proposal was introduced by the Swiss Delegation to the UNESCO's General Conference at Paris, October, 1989:
"The General Conference, 1. Being convinced that identifying and ameliorating global changes leading to environmental devastations and irreversible depletion of natural resources is one of the most urgent scientific problems of today, and that this problem can be solved only through multinational and interdisciplinary cooperation, 2. Considering that the development and progress of civilization on Earth will to a large extent be determined by the quality of the environment and by the capacity of nature to
INTRODUCTION
3.
4.
5.
6.
achieve stable biological reproduction in all its natural diversity, Noting that cooperation between the UNESCO and the scientific community represented by the International Union of Geological Sciences in form of the U N E S C O / IUGS International Geological Correlation Program (IGCP) has proved an effective model for multinational and interdisciplinary cooperation to tackle geological problems relevant to the well being of the civilization, Understanding that environmental protection, preservation of the ecological balance, and non-hazardous exploitation of non-renewable natural resources make up one of the most important of mankind's tasks for insuring quality of life for future generations, Realizing that evaluating global changes and their deleterous effects on mankind can be made more effective by establishing a longterm programme involving the cooperation between UNESCO and the international community of scientists, with reference to the existing IGCP model, Decides 1. To invite the Director-General to study
3
the feasibility of cooperating with the International Union of Geological Sciences and the International Council of Scientific Unions to initiate a program on Earth Processes and Global Changes, as a contribution by U N E S C O / I U G S to ICSU's International Geosphere Biosphere Program. 2. To allocate US$20,000 within the proposed budget for 1990/91 for initiating pilot projects on Earth Processes and Global Changes of immediate urgency, such as short-term climatic variations of the past, anthropogenically induced environmental changes, or mass extinction of species induced by global changes." After its approval by the General Conference, it is foreseen that an I U G S / U N E S C O program on Earth Processes and Global Changes will be set up, with an administrative structure similar to the I U G S / U N E S C O International Geological Correlation Program. The program could then support interdisciplinary field conferences on specific regional projects, to facilitate international exchanges of scientific data, methodology, samples, and of academic personnel.