This Plan (Version 2.0) has been developed by the Terrestrial Observation Panel for Climate (TOPC) to meet the terrestrial requirements for the Global Climate Observing System (GCOS) and the climate change requirements of the Global Terrestrial Observing System (GTOS), and represents a significant update of Version 1.0 (GCOS-21). The TOPC is a joint panel established by the GCOS and the GTOS to ensure that a coordinated Plan is produced and implemented. The data and information management needs identified in the Plan have been passed to the GCOS/GTOS/Global Ocean Observing System (GOOS) Data and Information Management Panel (JDIMP) for implementation in conjunction with other GCOS, GOOS and GTOS needs. Likewise, for those observations which can best be made from space, the requirements have been passed to the GCOS/GTOS/GOOS Space-based Observation Panel (SOP) for coordination with the world's space agencies. The strategy for implementing the in situ aspects of the Plan will be a joint effort between GCOS and GTOS, in cooperation with the World Climate Research Programme (WCRP), the International Geosphere-Biosphere Programme (IGBP), the International Human Dimensions Programme (IHDP), and other international and national institutions. It is intended that the Plan will be refined and updated as required.
The land-atmosphere interactions, which link the land surface with the atmosphere, are critical processes for understanding and assessing the impact of climate change. An integrated global observing system is needed to address critical questions in these links. For example: Is the carbon storage in the terrestrial biosphere growing? If so, at what rate? Is the tundra permafrost melting? If so, at what rate? (If it does, millions of tons of carbon dioxide and methane could be released into the atmosphere, greatly accelerating the rate of global warming.) Are there shifts in species and vegetation patterns in response to a changing climate?
The objective of this Plan is to provide a rationale for the structure of the initial operational system and to outline basic guidelines for its implementation. It describes the minimum set of land-based variables that are required to understand the climate system and its variability and to predict, detect and assess the impacts of climate change. The Plan outlines a strategy which will enable collection of the observations so that consistent global data sets can be produced.
To develop a rational approach to planning the global observing systems, the TOPC undertook a series of tasks, described in the subsequent chapters:
Analysis of the climate- and climate change-related mechanisms governing the function of the key terrestrial components of the climate system, including identification of the key variables that need to be measured: biosphere (Chapter 2), hydrosphere (Chapter 3), and cryosphere (Chapter 4);
Discussion of sampling requirements and problems, leading to the conceptual definition of a global sampling system for terrestrial observation building on existing systems and facilities (Chapter 5);
Discussion of data and information system requirements and issues (Chapter 6);
Development of an implementation plan, with emphasis on the initial operating system (Chapter 7);
Description of individual terrestrial variables to be measured by the GCOS/GTOS, including their specific attributes (frequency, accuracy, current status, measurement method, research and development (R&D) and action required, etc. (Annex I).
The Global Climate Observing System (GCOS) is a joint initiative of the World Meteorological Organization (WMO), the Intergovernmental Oceanographic Commission (IOC) of the United Nations Educational, Scientific and Cultural Organization (UNESCO), the United Nations Environment Programme (UNEP), and the International Council of Scientific Unions (ICSU). GCOS provides an international forum for the development of a comprehensive long-term global observing system that will improve our understanding of climate. A more complete description of GCOS can be found in the Plan for the Global Climate Observing System (GCOS-14).
In the current debate about climate change, it is evident that information available to governments is inadequate to enable them to obtain answers to critical scientific, economic and policy questions. This gap is likely to be more critical in the future as the earth's climate, its biosphere and human activities respond to increasing greenhouse gas concentrations. In particular, systematic and comprehensive global observations of the key variables are urgently needed and should be made available to nations to enable them to:
Detect and quantify seasonal, and inter-annual climate changes at the earliest possible time;
Document natural climate variability and extreme climate events;
Model, understand and predict climate variability and change;
Assess the potential impact on ecosystems and socio-economical conditions;
Develop strategies to diminish potentially-harmful effects and amplify beneficial ones;
Provide services and applications to climate-sensitive sectors; and
Support sustainable development.
Objective of the GCOS
The objective of the GCOS (GCOS-14) is to provide the observations required to meet the needs for:
Climate system monitoring, climate change detection and response monitoring especially in terrestrial ecosystems and mean sea-level;
Application to national economic development;
Research towards improved understanding, modelling and prediction of the climate system.
Background to the GCOS
International concern regarding climate change is encapsulated in the Framework Convention on Climate Change (FCCC) signed by over 160 nations in June of 1992 at the Earth Summit in Rio de Janeiro. Ratified by over 50 of those countries, the Convention came into force on 21 March 1994. The Convention clearly recognizes that climate change due to human activities may "adversely affect natural ecosystems and humankind". It further recognizes that actions concerning climate change must be taken in the overall context of sustainable development. In addition to the Climate Convention described above, the Convention on Biodiversity and the United Nations Convention to Combat Desertification both require climate observations, and in particular systematic terrestrial observations for their full implementation.
A substantial capability for the required observations from both in situ and space-based observations already exists, principally in operational programmes (e.g., World Weather Watch (WWW) for operational meteorology, National Aeronautics and Space Administration (NASA)/ National Oceanic and Atmospheric Administration (NOAA) Pathfinder programme) and in research programmes (e.g., WCRP, IGBP). Despite the scope of these programmes, even when taken collectively, they are inadequate to meet the objectives described above. To be comprehensive, an observing system must address the critical parameters by making measurements with adequate precision, sufficient spatial and temporal resolution, and with known long-term continuity. The products must be in a form that can be easily utilized by policy - and decision-makers at national, regional or global levels. For much of the land and climate system, such comprehensive observations and associated products are not available.
GCOS will improve the situation by taking a comprehensive, integrated view of the requirements for all the climate system components, including the global atmosphere, the oceans, the biosphere, the hydrosphere, the cryosphere and the linkages among them. Such an integrated view is necessary to adequately interpret climate variability, as well as to determine the naturally - and anthropogenically - produced climate changes. This Plan deals with three of these elements: the land biosphere, the cryosphere, and the hydrosphere.
The GTOS is a comprehensive land surface observation programme, with focus on five priority issues: land use and land cover change and degradation; water resources management; pollution and toxicity; loss of biodiversity; and climate change. This Plan deals directly with only one of these issues, i.e., climate change, but its recommendations have important implications for the others.
It is impossible to foresee all the critical environmental issues of the future. For example, who could have predicted the depletion of the ozone layer or the damaging effect of DDT on birds of prey? Once identified, how long did it take to get action? While the need for integrated and systematic terrestrial ecosystem monitoring has been recognized for over 100 years, there was no substantive international action to achieve it until the early 1970s. The Stockholm Environment Conference in 1972 catalyzed a number of monitoring activities which have made a positive contribution, but collectively they fall short of what is required. As a joint initiative of ICSU, WMO, the Food and Agriculture Organization of the United Nations (FAO), UNESCO, and UNEP, GTOS provides a comprehensive international forum for the development of an effective terrestrial observing system.
Objectives of the GTOS
The central mission of GTOS is to provide policy makers, resource managers and researchers with the data needed to detect, quantify, locate and give early warning of changes (especially reductions) in the capacity of terrestrial ecosystems to support sustainable development and improvements in human welfare, and to help advance our understanding of such changes. It should be accomplished through the development of an equitable partnership between the generators and users that meets both the short-term needs of national governments and longer-term needs of the global change research community.
GTOS data collection and analysis has four main objectives:
Identification and quantification of the natural and anthropogenic factors that affect terrestrial ecosystem function and structure;
Determination of the relative importance of these factors at the national, regional or global level and their interactions;
Distinguishing short-term natural variations or perturbations from long-term changes of anthropogenic origin;
Assisting modelling and multidisciplinary dynamic analysis of possible future changes in terrestrial ecosystems.
Background for the GTOS
Terrestrial ecosystems are the primary source of food. freshwater, fuel, clothing, and shelter for humankind and will continue to be so in the foreseeable future. They provide the main source of income and/or subsistance for the majority of the world's population, and for much of the developing world they are the dominant economic sector and source of substance and foreign exchange earnings. GTOS will provide the observational requirements that will allow governments to plan for and achieve sustainable development while mitigating environmental changes resulting from a number of anthropogenically produced factors, including climate change and desertification.
The initial planning for GTOS calls for pilot activities and progressive implementation over a number of years, with relatively low expenditure in the early stages. It has been designed to complement the other global observing systems, GOOS and GCOS, with the maximum use of common procedures.
The principal uses of GCOS/GTOS climate-related data are: (1) development of plans for sustainable economic and social development; (2) short-term climate prediction (seasonal to interannual); (3) long-term projections of future climate conditions (including climate model initialization, determination of boundary conditions, and validation); (4) climate change detection; and (5) assessment of climate change on ecological and societal systems. Some variables will assist all five uses and some are specific to a single group. It is important to realize that the primary users to be served by GCOS/GTOS will require both historical and current in situ and remotely-sensed (primarily from satellite-borne instruments) data.
Figure 1.1 shows the relationship between the observing system and the various objectives. The global data sets produced by GCOS/GTOS are a pre-requisite for improving our understanding of the global climate system and its components (atmosphere, biosphere, hydrosphere, cryosphere, and lithosphere). Improved computer models of the climate system, capturing our best knowledge of the mechanisms of climate processes and climate-related interactions between the various components, can be produced using the data sets. Of special importance are general circulation models (GCMs), biogeochemical global climate (BGC) models, and trace gas models. Both data sets and the understanding/models are employed in tracking the variability, changes and impacts of the climate system, as defined by GCOS/GTOS objectives. The resulting findings will be essential for a variety of purposes, mostly at the national level, related to economic and social development, national security, health, international cooperation, environmental protection, and others. Note that the observing systems need to be responsive to feedbacks from the end uses and also to new insights into the climate system and the mechanisms governing its behaviour.
Figure 1.1 - Relationship
between the Global Observing Systems and their objectives.
Climate change data are a critical factor in planning and managing sustained economic development, particularly in the field of agriculture and land use (e.g., sea level rise). GCOS/GTOS will help improve the reliability of predictions, both in the short and long term, as to which areas are likely to experience drought and which increased precipitation. This will have direct implications for enhanced international cooperation in terms of regional and national response strategies.
For climate prediction and the development of scenarios, two complementary time scales are of interest: (1) the seasonal-to-interannual time scale in which the predictability of certain phenomena can be exploited for socio-economic benefit; and (2) the decadal-to-centennial time scale in which the stability of the climate with respect to anthropogenic influences and the early detection of any climate change must be assessed and the future climate state predicted. Accurate predictions of seasonal and interannual climate variability, such as El Niño/Southern Oscillation (ENSO) events, are of immediate application and a large economic value in many regions of the world. Our ability to accurately predict climate on various time scales is a prerequisite for any rational plan to adapt to or mitigate negative consequences of climate changes. Accurate climate projections are critical to planning for long-term sustainable development. More directly, the ability to predict climate on a seasonal basis will be directly useful to many economic activities world-wide.
Improvements in our understanding of climate change and terrestrial ecosystem interactions, and in the predictive powers of GCMs and other global environmental models, is critically dependent on the greater integration and analysis of the data on socio-economic driving forces and the biophysical and bio-geochemical responses. Key socio-economic driving forces include population growth and density, per capita income levels and growth rates, and technological change. Data on these forces are commonly subject to wide errors, collected at irregular intervals, and seldom geo-referenced. It is therefore important that GCOS and GTOS: (a) assure improved collection and accessibility of terrestrial data; (b) coordinate their activities with the various national and international bodies that are focusing more directly on filling the socio-economic data gap (e.g., the Consortium for International Earth Science Information Network (CIESIN); the International Human Dimensions Programme); and © ensure that the data management system will allow terrestrial data to be readily integrated with socio-economic data once it becomes available.
It is well known that the Earth's temperature is controlled by the balance between incoming radiation from the sun and outgoing radiation from the Earth. Certain atmospheric constituents (e.g., water vapour, carbon dioxide, tropospheric ozone, and methane) absorb outgoing radiation. In general, as concentrations of these constituents increase, the temperature of the earth is predicted to increase.
Currently at issue is the stability of the climate system when perturbed by significant emissions of greenhouse gases into the atmosphere. The best current estimate is that by the year 2100 global mean temperatures will have risen by 2.0 degrees C (Watson, et al., 1996). Regional temperature changes may differ substantially from the global mean, but it is not yet possible to say by how much. While there are uncertainties, the balance of evidence suggests that human activity over recent decades has contributed to recent climate change (Watson, et al., 1996). These changes are likely to affect not only the temperature but also patterns of precipitation, floods, droughts, storm frequency or intensity, length of the growing season, water availability to plants, and other related phenomena with direct impact on the human population. Changes in the total amount of precipitation and its frequency are likely and will directly affect the magnitude and timing of runoff and the intensity of floods and droughts (Arnell, et al., 1996). As a result of such meteorological variations, many other sectors of the society would be profoundly affected. If we are to manage change for the benefit of humankind, it is critical to detect the change that is occurring on a regional as well as global basis and assess the amount of change taking place due to climate. For example, global change has potential consequences for changes in the distribution, viability, and sustainability of ecosystems on which humans depend. Global changes are caused by a number of specific anthropogenic stresses, including climate change, land use change, habitat loss, landscape fragmentation, and desertification resulting from land management practices.
The value of better information about climate change is large. To continue to address climate requirements, long-term global observations of many climatological/meteorological, oceanographic, chemical, and biospherical parameters, are vital (Watson, et al., 1995).
If the climate-related objectives of GCOS/GTOS are met, nations will be able to significantly improve their ability to predict short- and long-term climate, detect the impacts of change and assess the influence of climate on global change, thus improving their ability to plan for effective sustainable development.
