Pierre-Philippe Mathieu, Stephen Coulson
European Space Agency, ESA/ESRIN, Via Galileo Galilei, 00044 Frascati, Italy
Measure from Space what we Treasure on Earth
For more than half a century now, since the launch of Sputnik in 1957, ÛÏEarth ObservationÛ (EO) satellites have been monitoring our global environment, revealing its fascinating beauty while demonstrating at the same time its inherent fragility and exposure to rapidly growing human-induced stresses (e.g. ozone hole, and climate change).
The unique perspective from space, epitomized by the iconic ÛÏEarth RiseÛ picture (taken in 1968 during the Apollo 8 mission), also contributed to the emergence of the concept of ÛÏSustainable Development,Û by convincing many of the need to better manage the limited (and rapidly depleting) natural resources of our home planet in a more sustainable manner for the benefit of future generations.
Over the last decades, the principles of Sustainable Development – broadly defined within the Bruntland report ÛÏOur Common FutureÛ (1987) – have been progressively adopted by world leaders following a series of Earth Summits (Stockholm, 1972; Rio, 1992; Johannesburg, 2002). Development targets, such as the Millennium Development Goals, have been defined during these summits and agreed upon by policy makers and business sectors in order to improve quality of life, protect the environment, and fight global poverty and hunger.
In this context, large ÛÏMultilateral Development BanksÛ (MDBs), such as the ÛÏWorld BankÛ (WB), and the ÛÏEuropean Investment BankÛ (EIB), adopted a series of sustainability principles to better account for social and environmental risks in project financing. Large MDBs started to routinely implement sustainability principles (including environmental aspects in addition to social and economical ones) at the heart of their financing practices. In parallel, new economic concepts like ÛÏEcosystem ServicesÛ and incentive schemes like ÛÏPayment for Ecosystem ServicesÛ (PES) were being developed and designed in order to put an economic value on environmental resources and secure preservation and restoration of ecosystems (e.g. carbon sequestration, biodiversity, watershed payment schemes).
Figure 1: Collaboration between World Bank and ESA on Climate Change adaptation. Working Session during the 5th Urban Research Symposium on ‘Cities and Climate Change: Responding to an urgent agenda’ (28-29 June, Marseille, 2009). From left to right: Anthony G. Bigio (World Bank), MaanChibli (Mayor of Aleppo City), Pierre-Philippe Mathieu (ESA), Yves Ennesser (Egis Bceom International).
The need to account for the ÛÏenvironmental dimensionÛ in financing projects has driven a growing demand for geospatial information within MDBs in order to better assess the environmental footprint of projects, from their appraisal phase up to their implementation. Recent publications by MDBs, such as the WB ÛÏWorld Development ReportÛ (WDR 2009: Reshaping Economic Geography, WDR 2010: Development and Climate Change), and their growing contributions to meetings of parties to international conventions (e.g. UNFCCC, UNCBD) highlighted the increasing concern for global environmental issues (in particular Climate Change), and the need for spatializing the development information (e.g. getting environmental and economic data on the same map). This also raised new challenges, as MDBs are not necessarily equipped with the proper tools and technology to objectively gather such information.
EO satellites can help MDBs to meet this challenge. They are uniquely placed to measure the cumulative environmental impact in a synoptic and consistent manner around the globe, even in the most remote places, where in-situ surveys cannot be performed effectively. This is particularly useful as the problems addressed by MDBs have often a global nature, and therefore require global data.
A set of about 10 initial, small-scale pilot projects aiming to demonstrate the value of EO information services to support the development sector have been performed in partnership between the ÛÏEuropean Space AgencyÛ (ESA) and various MDBs (e.g. EIB, WB), within the framework of the ESA Value Adding Element (VAE) program. The main aim of the VAE is to support European and Canadian geo-spatial information industry efforts to develop and grow the prospects of EO services being used in businesses and organizations for their operations.
Figure 2: Assessing Progress in Re-Plantation Projects. The land cover map of 2008, based on SPOT and Landsat data, showed that the re-plantation project has resulted in a 220ha increase in new plantation (mainly Eucalyptus) area (in pink) inside the EIB project area (AOI1 in red contour). The area in white could not be classified due to the presence of clouds. Courtesy GRAS, Spot Image, and help of Luxspace Sarl.
A subset of these projects are briefly presented in the following section. They address a variety of development issues; ranging from the sustainable exploitation of natural resources (e.g. mining) and ecosystems (e.g. coral reef), to the adaptation to climate change for coastal cities (eg. North African region). The projects were set-up in partnership with the WB and EIB project officers, their end-users, and the ESA VAE team. Close dialogue took place to understand exactly what information was required, which specific EO products could make the most valuable contributions, when the information was needed, and how it might be used. The EO products (tailored to the specific needs of MDBs) were then procured under the technical guidance of the ESA team from the European and Canadian geo-information service industry. This was done in an open, competitive manner, with the best proposals selected. The EO products were produced and delivered to the users together with a product description and measure of quality. The usefulness and benefits (as well as the limitations and constraints) of this information was then assessed by the MDBs, and results presented at various meetings, including a workshop in EIB and meetings organized by the WB in Marseilles (Fig. 1), Alexandria and Tunis.
Fostering the use of Earth Observation into development and financing practices
(1) Monitoring re-plantation activities in the Solomon Islands
This demonstration aims to monitor the extent of re-forestation activities in Kolombangara, a small island located in the Western Province of the Solomon Islands. The EIB needed information on the progress of forest replanting that started in 2007.
EO-based information on Land Cover, together with area statistics and fragmentation metrics (edge density), were delivered to EIB by GRAS (Geographic Resource Analysis and Science), based in Denmark.
The EO-based land cover classification products (Fig. 2) were used to assess progress in the re-plantation project by identifying patterns of change, and in particular the extent of new plantations. The land cover change information enabled the project promoters to identify the ÛÏhot spotÛ regions, which require careful in-situ monitoring, and thereby help them to better manage resources by optimizing (expensive) field surveys. It also provided them with synoptic information complementing local data (available mainly in paper format), as satellites are able to monitor the most remote regions of the island, where in-situ surveys are difficult to perform or sometimes simply not possible.
Ultimately, EO images appeared to be an excellent communication tool, providing a synoptic picture of the project to support dialogue with local stakeholders and show the value of the investment.
Figure 3: Land cover data in 2008 over the Ambatovy mining site. Courtesy KEYOBS, Spot Image.
“The service provides useful information about the land cover of the area, both in the EIB project area and on the rest of the island, and it verifies the progress of the replanting,” said Mr Harald Jahn, Head of Division Services & SMEs, Argo-Industry in the Projects Directorate of EIB.
(2) Quantifying environmental impact of Mining activities in Madagascar
This demonstration aims to set the baseline for monitoring the environmental impact of a nickel-cobalt mining and processing project partly supported by the EIB in Eastern Madagascar (Ambatovy). This includes the development of a mining site, a refinery close to the harbor on the coast, and a connecting pipeline. In order to limit the environmental impact of the construction, the project proposed the establishment of forest buffer zones at the mining site and of an off-set area of primary forest located at Ankera, 60 km southÛwest of Toamasina.
EO-based information on Land Cover (Fig 3), based on optical data (e.g. SPOT-5, Landsat ETM), was provided to EIB by Keyobs, based in Belgium. This information provided the EIB with a synoptic picture of the environmental footprint of the project, facilitating the preparation of a dedicated field visit, and setting the baseline for future monitoring of the effectiveness of the planned biodiversity protection measures (e.g. forest buffer, preserving primary forest). The potential of the EO to quantify the environmental impact of international mining activities at the global level, in a consistent, verifiable and cost-effective manner, was also acknowledged as a key advantage of the technology to further support global reporting.
“The service has been a success. It provides valuable information about the land cover of the area, demonstrates to the users exactly what can be monitored and allows them to make an informed decision about whether and how to proceed with EO-based monitoring of this important project,” said Mr. Eberhard Gschwindt, Technical Advisor in the EIB Projects.
Figure 4: Quantifying Vulnerability of Coral Reef Habitat in Belize. Thermal stresses quantified by the Monthly average temperatures for the warmest month of the year (SST) in Belize, based on ESA AATSR (Along-Track Scanning Radiometer and the Advanced Along-Track Scanning Radiometer) from 1991-2008. This temperature data allows categorization of coral reefs in Belize by thermal stress regime. Empty (white) polygons are unclassified, falling between thermal regimes. Reefs were classified according to their past temperature patterns into the categories: (A) High chronic (thus acclimated) and low acute stress, expected to cope best with rising temperatures, (B) High chronic and high acute stress, where the selection for more thermally-tolerant genotypes would be greatest, (C) Low chronic and low acute stress, not acclimated to any thermal stress and expected to be fair badly if subjected to unusual warming and (D) Low chronic and high acute stress, likely to be the worst-affected by climate change. More information in Mumby et al., 2011, Reserve design for uncertain responses of coral reefs to climate change. Ecology Letters 14: 132-140. Credits: MSEL, University of Exeter
(3) Assessing environmental stresses on Coral reefs habitat and related Ecosystem Services in the Caribbean Sea
This demonstration aims to support a strategy implemented by the WB for preservation of coral reef sites. The focus is the ÛÏMesoamerican Barrier Reef SystemÛ (MBRS), which is the second longest barrier reef in the world after the Great Barrier Reef in Australia, extending over 1,000 km from Mexico to Honduras. The MBRS provides a wealth of Ecosystem Services (e.g. coastal protection, fishery, tourism, habitat for species), fundamental for the livelihood of the inhabitants of Belize. It is significantly exposed to overfishing and tourism activities, as well as enhanced warming and acidification of the ocean induced by climate change. In order to preserve these sites, the WB would like to better understand their specific risk exposure and vulnerability.
Maps of Coral Reef habitat were produced by the University of Exeter, based in the UK, using optical and microwave data, and including ESA missions (e.g. Envisat, ERS). These maps contained quantitative information on a number of important factors influencing the coral’s health, such thermal stress regimes and wave exposure areas. Fig. 4 illustrates the components of the thermal stress, distinguishing between the ÛÏchronicÛ stress (measured as the climatological summer temperature average), and the ÛÏacuteÛ stress (measured as the frequency of degree heating weeks) induced by prolonged elevated temperatures leading to bleaching events .
These habitat maps provided WB managers with a unique insight into the level and regional distribution of vulnerability of reef sites, helping them to better quantify the risk of bleaching associated with climate change (e.g. region of acute thermal stress), and overfishing activities. The EO information also provided users with insight into potential sites for reef re-breeding, in a more objective manner, thereby optimizing financial resources and maximizing the potential of related Ecosystem Services.
“Space-based observations are an essential element of climate monitoring in Latin America and a complement to ground-based stations,” said Walter Vergara, Lead Engineer-Latin America Environment Department at the World Bank. “ESA instruments and observation protocols are particularly applicable to the type of information that needs to be collected over time in the Americas.”
(4) Understanding subsidence risk of coastal cities in North Africa
This demonstration aims to better quantify land subsidence risks in Alexandria and Tunis, by use of a particular type of ÛÏInterferometric SARÛ (InSAR) technique, known as the ÛÏPersistent Scatterer InterferometryÛ (PSI). The ground motion maps were derived by the PSI technique from Radar data (e.g. ESA’s Envisat, ERS and the Japanese ALOS) by two specialist companies; Altamira Information of Spain and TeleRilevamento Europea (TRE) of Italy. The maps were used to spot the regions at risks, and integrate the geological analysis of soils and earthquake risks, considered significant for Tunis.
The results of this study, obtained using InSAR technology, highlighted the regions of subsidence in Alexandria (e.g. border of the Mariut Lake and near the village of Idku) as well as regions of uplift of the ground in rural and urban areas. In the case of Tunis (Fig 5), the results highlighted subsidence in the central part of the city, built on reclaimed land. This EO-based information was used by the WB as an input to a wider study funded by the WB on the vulnerability and adaptation of coastal North African cities to climate change risks and natural hazards (Fig. 1 illustrates a workshop where the study methodology was presented).
“There is currently very little scientific evidence of the land subsidence taking place in the main cities of North Africa, and EO from space can help in assessing the risk by showing the local details in a regional context, highlighting hot spots of identified land motion and prompting experts and decision-makers to remedial actions for risk mitigation,Û said Anthony G. Bigio, Senior urban specialist at the World Bank, in charge of the study for the Middle East and North African Region
Figure 5: Assessing land motion in Tunis City. SqueeSAR analysis of ERS ascending data identified more than 70000 measurement points, with a density of about 70 PS/km2. For each point, the average rate of deformation and time history of movements were estimated. The colored markers, superimposed on the satellite image from Microsoft Virtual Earth, in each velocity field maps correspond to the measurement points identified in the AOI: positive values (blue) of the measured displacements indicate movement toward the satellite along its line of sight, suggesting an uplifting movement affecting the area, while negative values (red) indicate movement away from the sensor, that may attributed to a subsidence phenomena affecting the area. Courtesy TRE.
Conclusions
Development issues and Global Environmental Change issues are intrinsically linked, as the livelihoods of many people (particularly those in developing countries) are critically dependent on rapid changes in the environment and climate. The success of development projects increasingly depends on the ability of MDBs to effectively monitor changes in the environment, at the local and global scale in order to better mitigate or adapt to them.
A few small-scale projects, performed in partnership between the WB, EIB and ESA, were discussed here to illustrate the value of wide-area information from satellites to support MDB’s development activities across their life cycle: from appraisal and due diligence, to monitoring and post-evaluation of projects. Within this context, EO-based information has helped users to:
Û¢ Check rapidly the ÛÏProgressÛ and ÛÏEnvironmental ImpactÛ of their projects, at the regional and global scale;
Û¢ Establish a ÛÏBaselineÛ from the satellite archive, against which ÛÏchangesÛ can be detected and ÛÏOffsetÛ measures can be determined;
Û¢ Identify ÛÏHot SpotÛ regions, which would require further attention and field surveys;
Û¢ Support ÛÏDialogueÛ with local stakeholders (often with divergent views) by putting environmental issues in a spatial context, in a consistent and objective manner.
The potential of Earth Observation satellites to assist MDBs is substantial and is likely to grow significantly with the new generation of satellite missions providing enhanced spectral, temporal and spatial capabilities. In particular, the availability of operational services will be improved through the ESA Sentinels missions to be launched from 2012 under the EC-ESA joint initiative for ÛÏGlobal Monitoring of Environment & SecurityÛ (GMES). In addition, a family of leading-edge scientific missions (Earth Explorers) are now being launched by ESA to measure key new parameters of the Earth system to better understand and quantify climate change.
Based on the initial successes, and in order to make full use of this growing potential, ESA is now initiating a more substantial and a wider range of EO service demonstrations tailored to the needs of MDBs.
The aim is to further raise awareness within the MDBs of the full capabilities of both European and Canadian EO missions (ESA and national), and providers of specialized EO services.
Acknowledgements
Many thanks to Willibald Croi (Luxspace Sarl) for his help during the projects and to the EO service providers for their products and comments.
Pierre-Philippe Mathieu (pierre.philippe.mathieu@esa.int) is an Earth Observation Applications Engineer in the Earth Observation Science & Applications Department of the European Space Agency in ESRIN (Frascati, Italy). He spent 10 years working in the field of environmental modelling, weather risk management and remote sensing. He has a degree in mechanical engineering and M.Sc from University of Liege (Belgium), a Ph.D. in oceanography from the University of Louvain (Belgium), and a Management degree from the University of Reading Business School (Uk).
Stephen Coulson (stephen.coulson@esa.int) has over 25 years experience in the field of Earth Observation and its applications, the last 20 of which have been with the European Space Agency. Since 2000, he has been managing an ESA program to support the development of the European EO services industry and is head of the Industry section in the Directorate of Earth Observation Programs in ESRIN (Frascati, Italy). He has a degree in physics from University of Durham (UK) and a Ph.D in theoretical physics from the University of Southampton (UK).