Geophysical Hazards

“Hazards – minimising risk, maximising awareness” is one of ten broad themes that make up the science programme of the International Year. This theme focuses on four key questions:

1. How have humans altered the geosphere, the biosphere and the landscape, thereby creating long-term changes detrimental to life and the environment and triggering certain hazards, while increasing societal vulnerability to geophysical (geological, geomorphological and hydrometeorological) hazards?

2. What technologies and methodologies are required to assess the vulnerability of people and places to hazards and how might these be used at a variety of spatial scales?

3. How do geophysical hazards compare relative to each other regarding current capabilities for monitoring, prediction and mitigation and what can be done in the short term to improve these statistics?

4. What barriers exist to the utilization of risk and vulnerability information by governments (and other entities) for risk and vulnerability reduction policies and planning (including mitigation) from each of the geophysical hazards?

To answer these questions the theme aims to closely integrate with parallel programmes at various levels within other international organizations such as UNESCO-IGCP, UN-ISDR, IGBP, IGOS and the Geoscience Unions’ Consortium with a primary focus being on how the four key questions of the hazards theme can be linked to the five action items of the UN-ISDR Hyogo Framework for Action.

What makes people and places vulnerable to natural hazards? What technologies and methods are required to assess this vulnerability? These questions are used to illustrate the circumstances that place people and localities at risk, and those circumstances that enhance or reduce the ability of people and places to respond to environmental threats. Vulnerability science is an emerging interdisciplinary perspective that builds on the integrated tradition of risk, hazards, and disasters research. It incorporates qualitative and quantitative approaches, local to global geography, historic to future temporal domains, and best practices. It utilizes technological sophistication and analytical capabilities, especially in the realm of the geo-spatial and computation sciences (making extensive use of GPS, GIS, remote sensing, and spatial decision support systems), and integrates these with perspectives from the natural, social, health, and engineering sciences.

Vulnerability research focuses on the intersection of natural systems, social systems, and the built environment. These three component areas intersect with the spatial social sciences to play a critical role in advancing vulnerability science through improvements in geospatial data, basic science, and application. The environment, individuals, and societies have varying levels of vulnerability that directly influence their ability to cope, rebound, and adapt to environmental threats. At present, we lack some of the basic operational understanding of the fundamental concepts of vulnerability, as well as models and methods for analyzing them. The focus on place-based applications and the differential susceptibility of populations to hazards is a key contribution of vulnerability science. Using examples derived from recent disasters, the role of the spatial social sciences in advancing vulnerability science are reviewed.

In recent years, UNDP, UN-ISDR, Munich-Re and other institutions have been pointing out the fact that the number of reported disasters as well as the economic losses associated with such disasters have been growing steadily in recent decades. But while in developed countries risk-reduction and risk-transfer mechanisms such as insurance allow citizens to cope with such disasters, the persistence of disasters in developing countries manifests existing incapacities to cope with such events and their impacts. In this context, UNU-EHS is taking a detailed look at the long-range implications of such a trend, particularly highlighting the issue of environmental migration triggered by environmental degradation and disasters.

In the scope of the Hyogo Framework of Action (HFA), research activities carried out within UNU-EHS on topics of vulnerability and risk assessment and early warning; as well as complementary activities targeting education and capacity building, may help visualize the link between the Main Theme and the HFA.

In concordance with the mission statement of the Institute: “Advancing human security through knowledge-based approaches to reduce vulnerability and environmental risks”; this paper reviews some of the research carried out by UNU-EHS which addresses key research questions like vulnerability assessment in case of tsunamis and floods in Europe and the Indian Ocean; institutional efforts at local, national, and regional levels on early warning and preparedness; the impacts of urbanization on the modification of hazards such as floods and landslides in capital cities of Latin America; and perceptions which may promote or inhibit the establishment of policies and plans to manage existing risks. Such examples should serve to visualize the links between the Main Theme: Minimizing Risk: Maximizing Awareness, and the four key research questions.

The paper concludes with a brief outlook concerning the current dilemmas and critical issues which need to be addressed in the context of human security in a changing environment, as well as the supporting role which UNU-EHS may have in researching such critical issues.

Communication is important in all aspects of the geosciences but is more prominent in the area of geological hazards, as the main audience for scientific information often lacks a geoscience background; and because the implications of not communicating results effectively can be very serious. Geoscientists working in the hazards area face particular challenges in communicating the concepts of risk, probability and uncertainty. Barriers to effective communication of geoscience include the complex language used by geoscientists, restriction of dissemination of results to traditional scientific media, identification of the target audience, inability to tailor products to a variety of audiences, and lack of institutional support for communication efforts. Geoscientists who work in the area of natural hazards need training in risk communication, media relations, and communicating to non-technical audiences. Institutions need to support the efforts of geoscientists in communicating their results through providing communications training; ensuring access to communications professionals; rewarding efforts to engage the public; and devoting sufficient staff and budget to the effort of disseminating results. Geoscientists themselves have to make efforts to change attitudes towards social science, and to become involved in decision making at a community level.

Weather-climate and geophysical hazards create many disasters around the world and the impacts have been devastating on many communities and countries. Over the decades there has been significant international scientific response, much of it organized by the International Council for Science (ICSU) and its partners in the United Nations system, especially the World Meteorological Organization and UNESCO. There is also an international policy response. For example, the UN Framework Convention on Climate Change, the 2002 World Summit on Sustainable Development and the related Millennium Development Goals and the World Conference on Disaster Reduction, held in Kobe, Hyogo, Japan in 2005, which agreed on the Hyogo Framework for Action. Through the deliberations of an ISCU-sponsored process, a new international research program Integrated Research on Disaster Risk (IRDR) – the challenge of natural and human-induced environmental hazards – has now been initiated, with the support of ICSU, the International Social Sciences Council and the UN International Strategy for Disaster Reduction. The focus of the research programme is on disaster risk and disaster risk reduction and takes an integrated approach to natural and human-induced environmental hazards through a combination of natural, socio-economic, health and engineering sciences, including socio-economic analysis, understanding the role of communications, and public and political response to reduce the risk. The legacy of IRDR will be an enhanced capacity around the world to address hazards and make informed decisions on actions to reduce their impacts. The IRDR Scientific Objectives are: 1: Characterization of hazards, vulnerability and risk; 2: Understanding decision-making in complex and changing risk contexts; 3: Reducing risk and curbing losses through knowledge-based actions. There are cross-cutting themes and approaches on: Capacity building; Case studies and demonstration projects; and Assessment, data management and monitoring.

Africa is impacted by a multitude of natural and human-induced hazards and disasters; such as drought, flooding, landslides, volcanoes, and earthquakes. These claim thousands of lives, devastate homes and destroy livelihoods. With more than 40% of the population living below the poverty line, sub-Saharan Africa is also the least-equipped and prepared continent to cope with the impacts of these events. In addition lack of detailed information on the economic impact of natural disasters makes it even more difficult to get an accurate picture of the damage caused by natural disasters. Whereas the impacts of different hazards and disasters impacting Africa are frequently interlinked, previous mitigation efforts have usually taken a fragmented approach. Moreover, available science programs at universities do not offer systematic theoretical foundations on vulnerability/sustainability science, nor do they teach practical methods in the fields of disaster prevention and management. These efforts have also been hampered by lack of databases and difficulties with effective dissemination of information. To address and find sustainable solutions to these challenges a scoping team of African scientists, organized by the International Council for Science, Regional Office for Africa (ICSU ROA) has assessed available knowledge and produced a science plan on natural and human-induced hazards and disasters in sub-Saharan Africa.

The science plan: (i) outlined the multitude of hazards which impact Africa, (ii) identified the gaps that exist in understanding the nature of this vulnerability, (iii) suggested measures that need to be taken for managing hazard risks, and (iv) proposed strategies for adapting to hazards. The science plan emphasizes the urgent need to build human and institutional capacity to fill in the knowledge gaps through a multidisciplinary involvement of academics in African universities and research institutions. ICSU ROA is now implementing the science plan while linking the planned activities with the objectives of the International Year of Planet Earth (IYPE) and other ongoing initiatives. This paper discusses current activities that are being undertaken by the hazard and disasters task teams of ICSU ROA to assess the risks posed by natural hazards in sub-Saharan Africa. The proposed initiative also stresses the importance of fostering outreach activities to strengthen the link between universities and society through carrying out joint initiatives on issues of hazards and disasters in Africa.

With the passage of time the impact of natural and human-induced environmental hazards and disasters continues to increase. ICSU is establishing a major new international initiative “Integrated Research for Disaster Reduction.” Considering that the geographical area covered by the ICSU Regional Office for the Asia and Pacific (ROAP) accounts for more than one-half of the world population and about 80% of all losses due to natural hazards globally, a Science Plan to address three categories of hazards, namely earthquakes, floods and landslides has been developed. We realize that the Asia-Pacific region has a large number of islands and island countries, which are more vulnerable to natural hazards due to their geographical locations. Therefore, the issue of islands and natural hazards is specifically addressed.

The niche of the proposed Science Plan is to utilize the latest knowledge and best practices to address problems related with earthquakes, floods and landslides so to prevent hazards becoming disasters.

Future population increase is expected to be concentrated in urban areas. The resultant urban expansion further increases both potential hazard and vulnerability to hydro-meteorological disasters. This is unique to hydro-meteorological disasters (especially flooding) and not the case for solid Earth events such as earthquakes and volcanic eruptions where the occurrence is independent of urbanization. The basic reasons for disaster occurrence in developing countries, especially in urban areas, are poverty and governance. They are socio-economic and cultural problems which can be solved only by an integrated approach in which all the stakeholders and administrative sectors have to work together while science and technology play a supporting role.

For the reduction of human losses by natural disasters, early warning, evacuation and preparedness supported by accurate forecasts play a key role. Hydro-meteorological disasters are in a better position in this respect than other disasters as their forecasting technology is much advanced. Nevertheless the capability of forecasting is not well utilized in local practice for civil protection from hydro-meteorological hazards. This is the gap between science and practice. The gap can be filled within the framework of integrated flood management where the local ownership of flood forecasts should be promoted, as tried by ICHARM (one of UNESCO Category II centers), to make warning an integral part of the total community management against disasters.

Geoscientific data combined with historical documents on past natural hazard events and on the disasters that followed are essential to improve mitigation plans. It is only with this method that the full scale of potential rapid changes that are not covered by the instrumental record can be obtained. Therefore, the collection of these past data and their integration into planning should become one of the priorities of the Hyogo Framework of Actions. This paper analyses the following five case studies: global warming impact on the indigenous populations at high latitudes of Canada, hurricane impact on the southern coast of the USA as experienced in New Orleans, rapid level rise in several lakes of the Argentinian Pampas with emphasis on Laguna Mar Chiquita, the rapid sea level rise of the Caspian Sea as seen from Iran and the tsunami risk in a large Alpine lake of Northern Italy, Lake Como. In each area, the main natural hazard is part of a potential series of hazards that, if combined, could lead to a shift from disaster to catastrophe. The most successful cases of transfer of information between geoscientists and end-users are when the hazards and subsequent disasters are visible or when the messengers bearing the information are trusted by the local communities.

The Indian subcontinent characterizes a continent-continent collision boundary in the north viz., Himalaya, subduction zone tectonics in the east, i.e., the Indo-Burmese arc extending through Andaman and Nicobar Islands to the Sunda trench in the south and rifted/non-rifted interiors of the Indian plate i.e., the Indian Peninsular shield. All these tectonic units are sources of damaging earthquakes capable of causing loss to property and human lives. A few recent examples are the Bhuj earthquake of 2001, Jabalpur in 1997 and Latur in 1993, all occurring in the Indian shield region and claiming more than 30,000 lives, collectively. Similarly, in the Himalaya, Muzaffarabad earthquake in 2005, Chamoli in 1999 and Uttarkashi in 1991 caused heavy casualties and severe damage to property. The 2004 Sumatra earthquake in the Sunda trench ruptured a 1,200 km long fault up to the north Andaman and generated an unprecedented tsunami in the Indian ocean that claimed hundreds of thousands of lives in the south-Asian region. Thus, strategies for the assessment of seismic hazard and mitigation efforts in these regions of varied tectonics require suitable practical solutions. This paper provide glimpses of the initiatives taken in the study of seismic hazard in the country and the activities during the IYPE.

This paper reviews, with a few out of many examples, recent advances in computational geodynamics related to modelling of stress localization and earthquake occurrence. These studies provide a basis for a comprehensive seismic hazard analysis. Several case studies are considered: tectonic stress modelling in the southeastern Carpathians and central Apennines; dynamics of the lithospheric blocks and earthquake modelling for the Sunda arc and the Tibetan plateau; and seismic hazard assessment for the Vrancea region. Possibilities for earthquake prediction, mitigation and preparedness based on the earthquake science and computer modelling are discussed.

Hazards related to groundwater–seawater (GW–SW) interactions in the coastal zone have been underestimated (Kontar 2008). This paper considers two case studies: one in Central Asia (Aral Sea region) and one in the Indian Ocean (December 2004 tsunami) that are important examples whose method of treatment provide insight into future feasibility studies of hazards in the coastal zone related to GW–SW interaction processes. The Aral Sea region is known as an ecological disaster zone. To provide reasonable living conditions for the coastal zone population, it is necessary to drastically improve the quality of the water used for human needs by developing a source of safe and sustainable groundwater input to the Aral Sea region. In the Indian Ocean tsunami waves, which affected thousands of kilometers of coastal zone in SE Asia, caused an ecological disaster by the large inflow of salt seawater into coastal aquifers. The tsunami has created an accelerating process of salt-water intrusion and fresh-water contamination in affected regions that now require drastic remediation measures. Analytical approaches have been developed for analysis of coastal water balance and temporal evolution of water basins and coastal aquifers after hazardous events.

This paper deals with the physical and environmental effects resulting from oceanic impacts by sizable comets, and the rates and risks associated with such cosmic impacts. Specifically, we investigate two sets of probable oceanic impact events that occurred within the last 5,000 years, one in the Indian Ocean about 2800 BC, and the other in the Gulf of Carpentaria (Australia) about AD 536. If validated, they would be the most energetic natural catastrophes occurring during the middle-to-late Holocene with large-scale environmental and historical human effects and consequences. The physical evidence for these two impacts consists of several sets of data: (1) remarkable depositional traces of coastal flooding in dunes (chevron dunes) found in southern Madagascar and along the coast of the Gulf of Carpentaria, (2) the presence of crater candidates (29-km Burckle crater about 1,500 km southeast of Madagascar which dates to within the last 6,000 years and 18-km Kanmare and 12-km Tabban craters with an estimated age of AD 572±86 in the southeast corner of the Gulf of Carpentaria), and (3) the presence of quench textured magnetite spherules and nearly pure carbon spherules, teardrop-shaped tektites with trails of ablation, and vitreous material found by cutting-edge laboratory analytical techniques in the upper-most layer of core samples close to the crater candidates.

Although some propose a wind-blown origin for V-shaped chevron dunes that are widely distributed around the coastlines of the Indian Ocean and in the Gulf of Carpentaria, we have evidence in favor of their mega tsunami formation. In southern Madagascar we have documented evidence for tsunami wave run-up reaching 205 m above sea-level and penetrating up to 45 km inland along the strike of the chevron axis. Subtly the orientation of the dunes is not aligned to the prevailing wind direction, but to the path of refracted mega-tsunami originating from Burckle impact crater.

The results of our study show that substantive oceanic comet impacts not only have occurred more recently than modeled by astrophysicists, but also that they have profoundly affected Earth’s natural systems, climate, and human societies. If validated, they could potentially lead to a major paradigm shift in environmental science by recognizing the role of oceanic impacts in major climate downturns during the middle-to-late Holocene that have been well documented already by different techniques (tree-ring anomalies, ice-, lake- and peat bog-cores).

Slow deformation and fracturing have been shown to be leading mechanisms towards failure, marking earthquake ruptures, flank eruption onsets and landslide episodes. The common link among these processes is that populations of microcracks interact, grow and coalesce into major fractures. We present (a) two examples of multidisciplinary field monitoring of characteristic “large scale” signs of impending deformation from different tectonic setting, i.e. the Ruinon landslide (Italy) and Stromboli volcano (Italy) (b) the kinematic features of slow stress perturbations induced by fluid overpressures and relative modelling; (c) experimental rock deformation laboratory experiments and theoretical modelling investigating slow deformation mechanisms, such stress corrosion crack growth. We propose an interdisciplinary unitary and integrated approach aimed to:

(1) transfer of knowledge between specific fields, which up to now aimed at solve a particular problem; (2) quantify critical damage thresholds triggering instability onset; (3) set up early warning models for forecasting the time of rupture with application to volcanology, seismology and landslide risk prevention.

The role of landslides in mountain regions is complicated. Landslides are considered as a mechanism of loss and the accumulation of dispersed mineral matter. They also play a role in the formation of new mountain relief and ecosystems, and the conservation of archeological and environmental information. The loss by landslides of fine earth, an irreversible resource, reduces the life-supporting resources of mountain regions. To investigate this a 15–100 year chronosequence of landslides was studied in the West Caucasus (Georgia), using case studies of stabilised slumps within newly settled agricultural areas with accumulated fine earth. Past landslides that buried settlements can be considered as “keepers” of scientific information recorded in cultural layers and fossil soils. The archeological site Gruzinka (North Caucasus, Russia) is such an example.