Figure 1 On the edge of the Sahara, the world’s largest non-polar desert, lies a large freshwater lake. Lake Chad borders four countries in West Africa: Nigeria, Niger, Chad, and Cameroon. Lake Chad was once the sixth largest lake in the world, but persistent drought since the 1960s shrank it to about one twentieth of its former size. The lakebed is flat and shallow, so small changes in depth mean large changes in area. Even in normal times, Lake Chad was no more than 16 to 26 feet (5 to 8 meters) deep. As the lake becomes shallow, large wetland areas replace open water. These images were taken by Landsat 1, 4, and 7 on December 8, 1972, December 14, 1987 and December 18, 2002, respectively.

Monitoring International Environmental Treaties

Using Earth Observation Data

KevinP. Corbley
Corbley Communications
Winchester, Va.

The interest in Earth observation (EO), or remote sensing, as a tool for monitoring international environmental treaties, also known as multilateral environmental agreements (MEAs), stems from parallel developments in the areas of Earth observation and international environmental diplomacy. Remote sensing technology and the rapid growth in the number of environmental treaties since the 1972 Stockholm Conference on the Environment have evolved on separate paths, converging only in the last ten years.

On the one hand, instruments are being launched with ever more impressive capabilities, and vendors are looking for new markets. On the other, the number of treaties in force is constantly increasing, and contracting parties are looking for easier ways to monitor not only their own and third party compliance, but also treaty effectiveness. The proliferation of MEAs has produced a new demand for environmental data and for better understanding of the socioeconomic processes and government policies that affect the environment. EO data are critical to understanding Earth systems and human impacts on those systems, and can ultimately contribute to the design of improved policy instruments.

Satellite EO data can measure a multitude of phenomena, from ocean temperatures to forest health and from ice thickness in arctic regions to rainfall rate in tropical regions. Nations that now have remote sensing capabilities include the U.S., Canada, France, Europe (through the European Space Agency, ESA), India, Japan, China, Russia, Israel, Brazil, Argentina and Nigeria. Their satellite capabilities have sensors focused on the Earth's land, oceans, and atmosphere. Data products can be generated for monitoring habitat of migrating animals, for detecting change in forests, crops, deserts and urban areas, or for monitoring pollution in rivers and deltas. Atmospheric measurements are made of carbon dioxide, ozone, methane and aerosols, including smoke and ash from fires and volcanic activity. See Figure 1.

Treaty Structures

Multilateral environmental agreements are typically brief and formal documents that describe the problem being addressed, the commitments of the governments involved, and the institutional infrastructure to be created. They are commonly cast in the form of binding international treaties. Most MEAs create a series of international organizations to administer the agreement, such as secretariats and technical and scientific committees, and invest the power to alter and amend the treaty in a Conference of the Parties, which acts by consensus in almost all cases.

International conventions on environmental protection are receiving increasing interest from both policy makers and scientific disciplines concerned with trans-boundary problems. Today more than 350 unique MEAs govern the cooperation of the participating nation states in protecting our common environment. These MEAs range from the 1933 Convention Relative to the Preservation of Fauna and Flora in their Natural State, which has nine Contracting Parties, to the 1994 UN Framework Convention on Climate Change (UNFCCC), which has 189 Contracting Parties.

Only a few MEAs have external monitoring functions explicitly written into the agreements, and fewer still incorporate or depend on Earth observation (EO) data to verify effectiveness or monitor compliance. MEAs mostly use as monitoring mechanisms either nation-level self-monitoring techniques such as registering inventories in a central repository or database, or an internal state census of various biological species, rather than external bodies or observations.

Parallels are often drawn between the international environmental treaties' regimes and the regimes of weapons and arms control treaties, especially when the concepts of compliance verification and monitoring are addressed. In general, the phases of treaty fulfillment are similar, but the objectives and governing structures are vastly different such that specific methods cannot be applied directly from one regime to another. The most important difference is that the objectives of the regimes are to effect change in the behavior of substantially different actors. For arms control treaties, the agreements are intended to affect the behavior of governments, and using sanctions can be effective to motivate compliance, while the environmental agreements attempt to affect the behavior of many private sector actors such as industries, consumers, and local farmers and villagers living off natural resources. These disparate actors are not necessarily motivated to change their behavior based on the enforcement of an international agreement, but providing incentives and information about the state of their environment may effect such change.

Forms of Monitoring

Compliance refers to a nation state's adherence to specific obligations under an agreement. A nation may take action to implement an agreement but still not be in compliance with those actions, e.g. not enforce the obligations under legislation due to lack of funding. A helpful distinction can be drawn between procedural compliance and substantive compliance. Procedural compliance concerns the fulfillment of obligations such as filing national reports, attending meetings, and other procedural requirements of an agreement, while substantive compliance involves fulfilling obligations specific to the intent of the agreement, such as emissions-reduction or conservation of species habitat.

Each MEA has its own regime for monitoring compliance. Almost all require some form of self-reporting. Traditionally, the incentives for states to report their own noncompliance are low, since such admission could lead to actions such as the imposition of sanctions. The situation changes when noncompliance is not necessarily considered the intentional act of a sovereign state but may be due to incapacity. Reporting a problem can lead other partners in the regime to look for remedies to overcome the difficulty, for example through a transfer of finances or technology. Using such a managerial approach, reporting noncompliance can be in the state's interest. The result of this new approach is a higher compliance record than with the enforcement approach.

Sanction mechanisms used within the arms control regime, based on the notion that states intentionally do not comply with treaty obligations, have proven largely ineffective for MEAs, and economic sanctions have become more difficult to apply since the international trade regime has become quite complex. One must take into account the abilities of states to comply when considering noncompliance. For example, under the 1987 Montreal Protocol to the 1985 Vienna Convention on the Protection of the Ozone Layer, given repeated evidence of non-compliance by the Russian Federation, not only were warnings given of potential suspension of trading rights, but financial assistance was offered through the Global Environment Facility (GEF) to improve data submission and implementation capacities. GEF funding was provided in similar circumstances to other former Soviet states. Emphasis was placed on improving the environmental management in those countries and highlighted the view that for MEAs, non-compliance is a problem to be solved, and not an action to be punished.

Successful monitoring of international commitments depends on the availability of data. Overall, national reports, which are the main source of these data, are becoming more complete, but the accuracy and comparability of data remain low in most cases. Environmental data, including EO data in these reports, would improve their quality significantly and provide the ability to quantitatively measure progress from one report to the next. The reliability problems of self-reporting are compounded by the fact that in most treaties the international body to which the information is submitted very rarely can take any independent action to confirm the national reports. There is no provision that authorizes objective verification of the data contained in national reports. Nor are there any automatic sanctions if reports are inadequate in content, are presented late, or are not presented at all.

Figure 2 Data from NASA’s Earth-observing Aura satellite in 2007 show that the ozone hole peaked in size on Sept. 13, reaching a maximum area extent of 9.7 million square miles – just larger than the size of North America – which was about average when compared to measurements from the last few decades.

Effectiveness is a measure of whether the objectives of a treaty are met. Effectiveness differs from compliance, although the two concepts are related. Compliance addresses whether an individual party to an agreement is meeting its obligations, while effectiveness addresses whether the agreement itself is achieving its negotiated goals. A state may comply with an agreement but the agreement may nonetheless be ineffective at achieving its objectives. For the Kyoto Protocol or its successor, for example, even if states fully comply with the requirements of the Protocol, it may still not be enough to stop climate change from occurring. The treaty would be ineffective. Yet, given the complexity of understanding the factors of effectiveness, compliance is often used as a proxy for effectiveness, since greater compliance generally leads to improvements in the environment. See Figure 2.

What is needed to measure effectiveness of an MEA is a set of quantifiable environmental indicators that show trends in environmental quality (atmospheric ozone, forest acreage and health, species counts for biodiversity, etc.). However, given that many MEAs are trying to address the complex interactions among different ecosystems on air, water, and land areas, a single indicator is difficult to develop. More significantly, MEAs rarely address all aspects of a given environmental problem, and instead tend to address one aspect of a larger environmental problem, possibly the largest contributing factor, but certainly not all of them.

Other sources of environmental problems and variations in domestic resources and implementation plans have a significant impact as well. Isolating the effectiveness of one MEA in mitigating a particular type of environmental risk is problematic. Also, aggregate data are gathered at the national level and reported in national reports for land-use, biodiversity, deforestation, protected areas, fresh water, pollution, and other concerns. Environmental quality in most of these areas, however is influenced by both domestic and external factors. MEAs, by definition, address global or trans-frontier effects, yet data are collected and assembled at the national level—a distinction that poses another problem for those trying to assess treaty effectiveness.

Objective Support for MEAs from OEData

Public support is required to develop agreements that address global or regional-scale environmental problems and is influenced by the existence and public sharing of scientific data, including Earth observation data. EO data are unparalleled sources of information that convey environmental changes in a visually compelling way, such that they are extremely useful for raising awareness and developing the political support necessary to negotiate environmental treaties at the international level.

For monitoring MEAs, once negotiated, factors that contribute to the usefulness of using EO satellite data include existing MEA structures (reporting and assessment requirements, sovereign vs. common territory sensitivities, and technical capacity of the contracting parties), physical measurements of EO data (ozone, land surface reflectance, ocean color, etc.), data accessibility, and data continuity with future sensors and missions.

Environmental problems addressed in many MEAs are global in scale, and EO data are well suited to large-scale problems such as deforestation, preservation of polar regions, ocean and atmospheric conditions, and climate change. For treaties requiring monitoring of land resources or coastal areas, contention with sovereignty issues continues to be prevalent. States are particularly sensitive about the availability of data on their economic resources and on activities related to their national security.

Figure 3 Carbon monoxide measurements from the Canadian MOPITT instrument on board NASA’s Terra satellite show air pollution traveling through the atmosphere. The false colors in these images represent levels of carbon monoxide in the lower atmosphere, ranging from about 390 parts per billion (dark brown pixels), to 220 parts per billion (red pixels), to 50 parts per billion (blue pixels). Notice the immense plumes of the gas emitted from forest and grassland fires burning in South America and Southern Africa in the October image on the bottom.

However, for MEAs dealing with atmospheric conditions and common spaces such as the oceans, EO receives little resistance and is often the only way of getting the measurements on the required scale to monitor the commons regularly. As atmospheric sensors improve in spatial and temporal resolutions, there may be more resistance to using the data for monitoring, since concentrations of atmospheric GHGs (greenhouse gases) can then be tied to specific regions or states. See Figure 3.

Environmental assessments are critical to measuring treaty effectiveness as they provide data on changes in the environment. The Millennium Ecosystem Assessment (MA) is the latest in a series of global integrated assessments conducted to assess the state of the environment using EO data. The MA consists of a global scientific assessment as well as a number of smaller, more focused local, regional and national assessments. The primary users of MA results include the international ecosystem-related conventions—the 1992 Convention on Biological Diversity, the 1994 Convention to Combat Desertification, and the 1971 Ramsar Convention on Wetlands—and their contracting parties. A much wider audience of United Nations (UN), governmental and non-governmental agencies also have the potential to refine their policies and programs based on the assessment results. Global in nature and consistent across nation boundaries, EO data are integral to the effort.

To date, the Intergovernmental Panel on Climate Change (IPCC) has produced four comprehensive assessments of global climate change (1990, 1995, 2001, and 2007), covering scientific and technical information for researchers and policy makers. The data are gathered, modeled and reported by scientists from around the globe, drawing on EO data and historical and current records of ground-based measurements. Climate models are used to project impacts of current trends in climate change. The First IPCC Assessment Report, completed in 1990, played an important role in establishing the Intergovernmental Negotiating Committee for a UN Framework Convention on Climate Change by the UN General Assembly. The second assessment report, Climate Change 1995, provided key input to the negotiations which led to the adoption of the Kyoto Protocol to the UNFCCC in 1997, and the 2007 report is driving the negotiations for the next Protocol to the UNFCCC.

Multilateral environmental agreements are evolving, open processes that are continually reviewing implementation and developing new measures to improve effectiveness. The number of MEAs, particularly at the regional and global level, will continue to grow, and Earth observation data can greatly contribute to the ongoing development and refinement of MEAs by assisting in problem definition and catalyzing action, by providing quantitative information in national reports to significantly improve their value both to the reporting nation and to the other parties of an agreement interested in compliance monitoring, and by providing global-scale environmental assessment to monitor treaty effectiveness.


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