Can Earthquakes Trigger Volcanic Eruptions?

Scientists from the United States Geological Survey's (USGS) Hawaiian Volcano Observatory have written an excellent article about the relationship between earthquakes and volcanic eruptions. Due to the fact that both volcanoes and active faulting occur on plate boundaries, these are closely related processes. Simply put, earthquakes change the stress field in the area in which they occur. These changes in the stress field can change the stress balance around magma chambers - bringing them closer to an eruption. Both the fields of seismology and volcanology are complex processes however, and therefore the interactions between these two systems are also complicated.

One reflection from reading this article, is the importance of understanding and incorporating the interaction of hazards within natural hazard risk assessments. If people have been affected by a large earthquake they will be more vulnerable to a volcanic eruption than if there had been no earthquake. Their properties may have been damaged, giving them less protection from ash, blocks of rock etc - and roads used as emergency escape routes may also have been damaged. This again highlights the importance of a holistic, multi-hazard approach to natural hazard analysis. 

Read the full article for more information.

Panama: Multi-Hazard Case Study

A very interesting multi-hazard case study in Panama is reported on the website of the Smithsonian Tropical Research Institute. Heavy tropical storms in December 2010 resulted in increased groundwater levels, higher pore fluid pressures, and thus slope instability... meaning there was significant landslide activity. This landslide activity resulted in large amounts of sediment entering the water system, and causing the water treatment plant of Panama City to be closed down for almost a month. The impacts of this lack of clean drinking water can vary from increases in disease, illness and maybe even death. This interaction of several factors resulted in a number of negative impacts to Panama City.

A number of measures could be taken to prevent this sequence of events. Avoiding deforestation, in order to prevent erosion would be one measure to reduce the probability of landslides. Ensuring adequate drainage in slopes would also reduce the risk. This sequence of events should also inform and educate emergency planners - helping them understand the vulnerability of their water supply system. Back-up systems should be in place, bottled water stockpiled, and potentially boreholes drilled in key locations such as hospitals and schools.

The Himalayas: Multi-Hazard Case Study

Source: Luca Galuzzi

Following on from last month's post about disaster risk reduction in Nepal, the BBC reports today of the threat of flooding in the Himalayas if earthquakes cause glacial lakes to rupture. As glaciers have melted, and continue to melt, they form lakes. In the event of an earthquake, the large ground accelerations result in these lakes bursting and causing considerable damage to property and infrastructure, as well as loss of life. Further problems can be caused when landslides (including seismically induced landslides) result in large amounts of material falling into lakes and causing them to burst.

This situation is an excellent example of a trigger mechanism (earthquakes, causing landslides, causing flooding) typically occurring in many areas affected by multiple hazards. In areas such as these a separate risk assessment for flooding, a separate risk assessment for landslides and a separate risk assessment for earthquakes will not adequately describe the risk in the area. It would be very easy to underestimate the vulnerability of people, and thus to conclude that the magnitude of risk is much lower than in the real case. Multi-hazard risk assessments would be a much more appropriate tool to understand the complex interaction of hazards in the Himalayan region. These take into account hazards triggering others, vulnerability being increased as a result of one hazard and the cumulative impact of multiple hazards. They try to give a much more 'real-life' view of the natural environment. Multi-hazard research is in a very young stage, yet it is very important and could greatly assist in disaster risk reduction programmes. 

Applying Technologies from Developed to Developing Countries

While there is a significant need for geologists to engage with international development, there's also a tremendous importance in developing tools, skills and technology in developed countries. In many situations, businesses, universities and governments of developed countries are willing to invest significant amounts of money in developing technologies and tools. This investment can often not be matched by many developing countries, but the technologies developed could eventually have a global use and be of benefit to millions in poverty. 

For example, the intrusion of saltwater into freshwater aquifers is a global problem, and a problem likely to increase if and when sea-levels rise, and coastal cities grow. Developing the technology to monitor and control this influx will require investment, research and development - and yet the outcome could be a relatively cheap technology that can be used globally. Coastal aquifers in the UK and Tanzania could equally benefit from similar technology.

Typical Coastal Aquifer (From: USGS)

A further example was published in the New York Times today, analysing the most and least safe cities affected by a number of natural hazards (including weather events such as tornadoes, hurricanes, hail and storms, floods and droughts, and earthquakes). The study gives an 'overall risk' map combining these events, and separate maps for hurricanes, tornadoes and earthquakes. Little information is given on how the 'overall risk' map was generated... the individual maps were generated using historical data and assessments from the USGS. The lack of description and methodology means it is hard to critically analyse the data within this multi-hazard risk assessment, and how it has been compiled. The development of software tools and methodologies for developed countries with a high risk of damage by multi-hazards (e.g. Japan, USA, China etc) could be extremely useful for developing countries which also suffer from a range of natural disasters such as landslides, floods, droughts, earthquakes (e.g. Nepal, Uganda etc).

Source: New York Times

Case Study: Disaster Risk Reduction - Nepal

The Guardian 'Poverty Matters' blog, focusing on global development, published an article by Alan Duncan today (Minister of State for International Development, UK) in which he highlights the importance of Disaster Risk Reduction in the Asian country of Nepal.

A) GEOLOGICAL & HAZARD CONTEXT

Nepal, situated north of India - in the Himalayas, is located in the collision zone of the Indian Plate with the  Eurasian Plate (right centre in diagram below). This results in a very high risk of earthquakes, with an estimated 10,000 people killed as a result of seismic activity between 1900 and 2008 (NSET-Nepal, 2010). The last major earthquake was in 1934, and palaeoseismology suggests that they occur every 70 years - meaning a major earthquake is due in the region.

In addition to earthquake hazards, Nepal also suffers serious problems from flooding and landslides - both of them resulting in more deaths than earthquakes in the period 1971-2008 (Landslides = 3987, Floods = 2936, Earthquakes = 873, as stated by NSET-Nepal, 2010). 

B) VULNERABILITY

Nepal is very vulnerable to natural hazards, rapid urbanisation - especially in the large city of Kathmandu, with poor spatial planning and disaster management means that communities are very vulnerable to a large earthquake, with a conservative estimate of 40,000 being killed, and many more injured (Asian Disaster Preparedness Centre). The range of hazards that could strike Nepal also complicate the situation. Communities are vulnerable to seismic-induced landslides, water-induced landslides, flooding and other hazards (wildfires etc), with the varied topography being a key factor in this. Poverty in this country increases the vulnerability to disasters. Building to resist earthquakes is expensive, and preparing communities requires investment. 

C) DISASTER RISK REDUCTION

As Alan Duncan states, there is a real need for action to reduce the risk in Nepal, by supporting the Nepalese government to develop their disaster management plans, investing in community education, urban planning resources and other risk reduction methods. As the Nepal Risk Reduction Consortium established by the UN work to support the Nepalese in preparing for disaster, and reducing the impacts of that - it is important to:

1) Ensure excellent communication between all stakeholders, including scientists, engineers, social scientists, town planners, politicians and community representative. 

2) Ensure a sustainable programme is put in place - drawing on community participatory methods to ensure that risk reduction is in place at all levels.

3) Develop multi-hazard risk assessments in order to better understand the complex nature of the hazards 

1. Communication

In order to develop detailed and thorough disaster management plans, and a disaster risk reduction plan, there must be good and detailed communication between stakeholders. Geologists and engineers must communicate with social scientists and urban planners in order to ensure the science is accurate and detailed, and incorporated into their plans and procedures. Communities must be consulted and their experiences and knowledge drawn upon to ensure a sustainable programme and policies (see below). 

2. Sustainability
In order to make disaster risk reduction sustainable there must also be substantial community involvement at every level - from identifying hazards, to educating communities, to determining how communities can build resilience and in writing disaster management plans. My experiences in water & sanitation work show that simply pouring finance and building institutional knowledge will not guarantee success or sustainability - without working with the community, drawing on community knowledge and involving them in the decision making. Community participation builds ownership, a sense of responsibility and community knowledge. In a similar way, if DRR is going to be successful in Nepal it must engage people from all aspects of the community and not be a 'top-down' exercise.


3. Multi Hazard Risk Assessments

There is a real need to develop multi-hazard risk analyses for this area. Single hazard risk assessments (i.e. one for flooding, one for landslides, and one for earthquakes) have the potential to result in increased vulnerability to other hazards - they fail to incorporate the complex interaction of hazards, triggering mechanisms, or the increased vulnerability to one hazard if it follows another hazard. Disaster Management Plans also need to examine wide-ranging factors such as water & sanitation, in order to determine how that will work in a disaster, hopefully preventing epidemics of diseases such as cholera.

Further information on multi-hazard risk assessments (in the context of Japan) can be found in this post.

D) CONCLUSION

As stated in this blog's analysis of the Humanitarian Emergency Response Review by Lord Ashdown, there is a definite need for investment in disaster risk reduction, and it is welcomed that DFID is taking this seriously. However, as outlined above it must be ensured that there is communication at all levels, and that it is sustainable, with community involvement and knowledge being fed into the process. A move to multi-hazard risk assessments is also suggested in order to better understand the complex interactions between hazards, and so improve the response in Nepal to future disasters.

The Role of Geologists in Humanitarian Emergency Response

As reported on Monday, a review into the UK’s response to humanitarian emergencies has been conducted by Lord (Paddy) Ashdown and released yesterday. The review outlines ways in which the UK can improve its response to such emergencies, and anticipate such emergencies. Incorporating these into the core of DFID’s work is crucial – making sure their development work and humanitarian assistance are integrated. 

The report highlights seven threads to the approach needed to be adopted including:

1.   A more anticipatory approach – using science to aid in the prediction of and preparation for such emergencies. It is important to be preparing for disasters as well as reacting to them (including equipping at-risk governments/civil society with the means to act).

2.   Resilience – working with local people to strengthen the community’s capacity to be resilient to an event. This was highlighted as an area that needs to become much more central to DFIDs development activities. Resilience will mean the damage is less lasting and communities can recover more quickly.

The report cites an interesting example where Mozambique asked in 2006 for £2million pounds to invest in preparing for the impacts of floods – which it could not receive. Soon after, the international community had to spend £60million pounds responding to a flood season

3.   Improve the strategic, operational and political leadership of the international humanitarian system, including pushing for reform within the UN’s response procedures.

4.    Innovate to become more efficient and effective – using the best of new technologies and science, new processes and practices, and new ideas from those affected. More investment needs to happen in research and evidence.

5.   Increase transparency and accountability towards both donor and host country populations. More conversation needs to occur between donors and communities to ascertain exactly what they need, how they can be helped and who can help them. Vulnerable people can often be overlooked. On the flip side, measuring the impacts of resources is a key way to ensure accountability to donors.

6.   Create new humanitarian partnerships to allow DFID to better influence and work within an increasingly complex humanitarian system. The need for multilateral work in this area is crucial, and while DFID is commended for adopting this approach it suggests they should work to enable new partnerships with emerging nations, NGOs, faith groups etc

7.   Defend and strengthen the humanitarian space – humanitarian workers should be granted access and protection as they give assistance in areas affected by conflict. DFID should work with agencies that can access and help those in need and humanitarian aid should not be politicised.

The full report can be found here.

Over the past couple of years we have witnessed some awful natural disasters that have required significant humanitarian assistance. Earthquakes have rocked developing countries such as Haiti, as well as more developed countries such as Chile, New Zealand and Japan. Floods have been catastrophic in Pakistan, and Australia, and large landslides and flooding have hit Brazil. The way in which the UK responds to such disasters – especially in developing countries where the effects disproportionately affect the population is very important. The UK is the second largest bilateral global humanitarian donor, although in terms of its percentage of GNI trails behind a number of countries.

The results of the Humanitarian Emergency Response Review are broadly welcomed. As developing countries are urbanising, vulnerability to disaster is in many ways increasing and steps need to be taken to ensure the international community’s response to disasters matures, as well as the anticipation of disasters and building of resilience develops.

Geologists have a very important role to play in the factors of anticipation, resilience and innovation.

ANTICIPATION: In disasters such as earthquakes, volcanic eruptions, floods, landslides etc – geologists study the science of how they occur and can use their skills to understand and recognise vulnerable areas. While prediction is not always possible, understanding of vulnerable areas, frequency and magnitude can be understood to a certain degree

For example: The study of palaeoseismology can provide information on the frequency of historical earthquakes and their magnitude. This information can help inform governments and civil societies to prepare. The UK for example knows to expect earthquakes up to approximately magnitude 6 following the M5.3-5.9 earthquake in the late 1500’s (although this size is extremely rare (See here for more info on UK Seismic Hazard). In Chile, they must prepare for earthquakes significantly bigger than this, at Magnitude 9 or greater.

Data for some hazardous areas can be significant, but often in developing countries the data is gathered at a much slower rate, and so is less sizeable, as governments can invest less in their own monitoring and evaluation programmes. Geologists can play a major role in building up knowledge of the mechanisms of hazards, their appearance in history and the likely impacts of the hazard.  

From: http://www.afronline.org/?p=3835

RESILIENCE: Building resilience to minimise the damage of the hazard is another area of humanitarian work that geologists can play a crucial role in. The education of communities to understand how hazards are triggered can help people recognise the warning signs for a number of hazards. Understanding the relationship between landslides and water can help communities construct simple drainage mechanisms, avoid the undercutting of slopes and ensure deforestation doesn’t occur on vulnerable slopes. Understanding the relationship between earthquakes and tsunami’s was not understood by many communities in the tragic 2004 Boxing Day tsunami in Indonesia, understanding the risk of a tsunami following an earthquake can give communities that vital extra time to move inland. Education can involve a community led, participatory approach in order to build a sustainable programme.

As well as education, improving physical structures can develop resilience. Geologists can play a major role in identifying which areas of the city are must vulnerable and how resilience methods can change from place to place. The types of buildings required to withstand earthquakes will differ from one rock-type to another for example.   

INNOVATION:  With regards to innovation, geologists are doing various pieces of research, and must do more, to improve the understanding and preparation for humanitarian emergencies. Geologists and other scientists must work closely with social scientists in order to develop and improve better risk assessments for developing countries – including the development of multi-hazard risk assessments. Research into the effects of global climate change at a local scale, and mitigating any risks, is fundamental research to be collated, as is how increased urbanisation will impact the consequences of disasters.

The response DFID gives to this review, and the speed at which they respond, will be very interesting. DFID must take seriously the importance of Disaster Risk Reduction, and the economic benefits of it, and ensure it is integrate into the core of its work. The crucial role that scientists can play in this sector must also be recognised further – not only in terms of health and agriculture – but also with regards to geology and engineering.

Japan: A Multi-Hazard Disaster

Our screens and newspapers have been filled with shocking images of the disaster in Japan over the past few days. In the age of 24 hour news, the world watched the disaster unfold as north-east Japan was struck by a major earthquake - 8000 times bigger than the one that struck Christchurch, New Zealand - followed by a tsunami causing widespread damage and destruction. The earthquake also triggered fires, landslides and now a possible nuclear disaster. In the coming weeks and months the full extent of the damage and loss of life will become clear.

The disaster in Japan demonstrates the complex nature of natural hazards, and the importance of forming a multi-hazard approach to preparing for and mitigating against natural hazards. The earthquake in Japan caused significant damage as buildings shook, roads cracked and structures collapsed. However it also triggered a number of other hazards. It had its epicenter under the sea, triggering the devastating tsunami that caused further damage and destruction. It caused slopes to become unstable, and landslides to occur. It caused gas leaks and subsequent explosions and fires. It has also potentially caused radioactive leaks, bringing a state of nuclear emergency.

Any of these hazards occurring on their own could cause significant damage - all of them occurring at one time is significantly worse than the sum of the damage that could have occurred if they'd been stand-alone disasters. For example, the damage to infrastructure from the earthquake would have increased people's vulnerability to the tsunami... making it more difficult to escape as roads were blocked etc. 

Landslide Blocked Roads:
http://nationaljournal.com/pictures-earthquake-in-japan-20110311

The hazards will also have increased human vulnerability to other possible disasters, such as disease and aftershocks. Since Friday aftershocks have struck the region, and they are likely to continue for many more weeks to come. The biggest aftershock is normally around a magnitude less than the main earthquake, meaning a large earthquake of approximately M7.5 could hit the area in the near future. It is possible and likely that this will cause further damage. Some of the damage this will do as an aftershock (after a major earthquake) will be greater than the damage it would have done if had just occurred as the main event itself. Slopes that were brought to a level dangerously close to instability by the M8.9 earthquake could fail. Damage done to infrastructure such as dams that has not yet been repaired could be exacerbated and failure occur. A risk assessment done for a M7.5 earthquake following the damage and destruction of a M8.9 earthquake and tsunami will be different to a risk assessment from a M7.5 earthquake. 

Japan M8.9 Earthquake & Aftershocks: www2.demis.nl/quakes/

The complexity of the situation in Japan, and the interconnectedness of the natural hazards must be reflected in how we approach disaster risk reduction and risk assessments for urban areas. Treating hazards as discrete events is far from the reality, and can lead to increased vulnerability. This said, most of the existing work into multi-hazard risk assessments (with rare exceptions) still view hazards as discrete events and fail to take into account (i) a hazard triggering another hazard, (ii) synergistic hazards bringing a greater risk than the sum of the individual hazards, (iii) one hazard increasing the probability of other hazards occurring. There is a growing need for further work and research to be done in this important area in order to develop and improve disaster risk reduction programmes.