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IAVWOPSG/4-WP/43
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International Civil Aviation Organization
WORKING PAPER / IAVWOPSG/4-WP/43
23/7/08

INTERNATIONAL AIRWAYS VOLCANO WATCH OPERATIONS GROUP (IAVWOPSG)

FOURTH MEETING

Paris, France, 15 to 19 September 2008

Agenda Item / 6: / Development of the IAVW
6.1: / Improvement of models used for forecasting the movement of volcanic ash
6.2: / Development of future satellite sensors and other systems to improve detection of volcanic eruptions and VA clouds

Issues arising from the 4th International Workshop on Volcanic Ash, Rotorua, NZ, March 2007

(Presented by Australia, New Zealand and WMO)

SUMMARY
The 4th International Workshop on Volcanic Ash was held in Rotorua, New Zealand, from 26 to 30 March 2007, immediately following IAVWOPSG/3. This paper summarizes the issues arising, notes various points of convergence with the IAVWOPSG works program, and discusses the outstanding issues of training and the ‘safe concentration of ash’..

1.INTRODUCTION

1.1The WMO 4th International Workshop on Volcanic Ash was held in Rotorua, NewZealand, from 26 to 30 March 2007, immediately following IAVWOPSG/3. The meeting was hosted by New Zealand, with assistance from Australia; representatives from these two countries chaired the organizing and scientific committees respectively. The meeting successfully built on the past WMO workshops hosted by France, and other significant events such as the 2004 conference hosted by the US.

2.Discussion

2.1The agreed summary of the workshop is given in Appendix 1. The group may wish to agree that the summary is a useful perspective to have available to members of the IAVWOSPG for reference, and might be included as an appendix to the report of this meeting.

2.2The group may also note that many of the issues discussed in the summary relate to matters now, or formerly, under consideration by the IAVWOPSG. This indicates a reassuring degree of convergence of thought on the issues that are important in the respective ICAO and WMO fora on volcanic ash. For example, the group may wish to note that previous IAVWOPSG conclusions on observatory sustainability (in terms of cost recovery and also the application of relevant parts of the Hyogo Framework) are consistent with the concerns expressed at the WMO meeting. Similarly, themes of use of infrasonic data, SO2 data for remote sensing, and dispersion model comparison are likely to continue to be discussed in the WMO context.

2.3Of the themes discussed at the workshop and not already discussed in separate working papers at IAVWOPSG/4, two might usefully be considered here.

2.4Firstly, a training sub-group was established at the Workshop, but no formal correspondence has taken place. The meeting may wish to agree that training is a critical element of the development and sustenance of IAVW, and that WMO should be invited to reconstitute the training subgroup prior to the IAVWOPSG/5 and the next workshop.

2.5Secondly, the past paragraph of the workshop summary suggested that ‘clear limits of ash content are required from both the manufacturers and aviation licensing authorities’. This refers to an indisputably difficult and longstanding problem; that there is no defined lower limit on ash concentration. As remote sensing techniques improve, it is likely that the aggregate areas where ash is sensed or inferred will increase, possibly leading to over-warning for ash and cost-blowouts for airlines. It should be recognized that progress on this issue would considerably aid the future operation of the IAVW, including in relation to the development of future satellite sensors, dispersion modeling, eruption notification procedures, and so on.

2.6The group may agree that this “safe concentration of ash” problem should properly be advanced in both IAVWOPSG and WMO fora, with scientific studies informing a decision-making process about the standards required from the warning system. As it has proven difficult to get formal aviation representation at science-focused workshops such as Rotorua, the input of the aviation industry to this problem might formally be sought through IAVWOPSG processes. A draft conclusion in this regard is given below.

3.Recommendation

3.1In regard to the above discussion, the following conclusions are proposed for the group’s consideration:

Conclusion 4/... — Summaries of the WMOworkshops
That the summary of the WMO 4th International Workshop on Volcanic Ash be included as an Appendix to this meeting report, and that, in principle, concise summaries of future Workshops should also be recorded for the information of the IAVWOPSG in the next appropriate IAVWOPSG meeting.
Conclusion 4/.. — Invitation to WMO to reconstitute training sub-group for volcanic ash
That, WMO be invited to reconstitute the training sub-group created at the 4th Workshop, and prepare a report for IAVWOPSG/5.
Conclusion 4/.. — Safe concentration of ash problem
That,
a)WMO be invited to further explore the problem of a “safe” or “acceptable” concentration of volcanic ash from the scientific viewpoint; and
b)IATA and IFALPA, and explore the issues from an industry viewpoint, and report in time for consideration by the IAVWOPSG/5 Meeting.

4.ACTION BY THE IAVWOPSG

4.1The IAVWOPSG is invited to:

a)note the information on this paper; and

b)decide on the draft conclusions proposed for the group’s consideration.

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A-1 / IAVWOPSG/4-WP/43
Appendix
IAVWOPSG/4-WP/43
Appendix

APPENDIX

WORKSHOP SUMMARY

Appendix1 – workshop summary

World Meteorological Organization
4th International Workshop on Volcanic Ash
Rotorua, New Zealand
26-30 March 2007

SUMMARY
The 4th International Workshop on Volcanic Ash was held in Rotorua, New Zealand, from 26 to 30 March 2007. The meeting heard of progress in many areas of the International Airways Volcano Watch (IAVW), including new remote sensing techniques. So far, no fatal aircraft encounters with volcanic ash have occurred, arguably as a result of the efforts of the IAVW. However, the meeting noted with concern that there have been several aviation incidents attributed to volcanic ash over recent years, including the double engine flame-out of a twin-engined aircraft at cruising levels over Papua New Guinea in July 2006.
The presentations given by the participants helped to identify areas of progress, but also those remaining questions that need to be addressed by both the scientific community and the operational users of the information.
To improve the science that supports the International Airways Volcano Watch, the following specific actions are suggested:

In order to achieve rapid and reliable alerts to new ash-producing eruptions, close monitoring of known, existing active volcanoes needs to be assured by both local and remote means. While space-based remote sensing has been instrumental in detecting many eruptions, the nature of polar orbiting satellites with infrequent overpasses, the limitations of some methods requiring daylight, and the ubiquitous presence of dense cloud in many areas underline the need for local monitoring. Infrasound measurements from the CTBTO or regional networks can improve detection, but for some instances a time delay in the order of hours may currently have to be accepted;

Any realistic hope of forecasting eruptions is entirely dependent on local monitoring by observatories. The meeting noted with concern that the resources available to many volcano observatories are insufficient. The meeting strongly encouraged States and international organizations to undertake a co-ordinated international effort to help in particular developing countries to establish and maintain effective volcano observatories throughout the world. The meeting recognized that it would be unrealistic to expect small island states and developing countries to shoulder the cost of such observatory operations which are partly or mostly in support of international aviation;

The meeting supported the efforts underway to investigate eruption source parameters as a means to improve ash dispersion forecasts;

It was found that weather Radar is very useful for the detection of eruptions, especially when volcanoes are near airports. There is a need to better quantify the uncertainty in determining the eruption characteristics from the radar data;

Uncertainty on the correlation between actual threat to aviation from ash and the presence of elevated concentrations of SO2, well-monitored by remote sensing, requires further investigation, in particular for eruptions including a pyroclastic flow, where SO2-rich and ash-rich clouds may be found at different heights, and may thus take totally different trajectories;

Comparisons between different transport and dispersion models used by the VAACs revealed a satisfactory consistency between different models regarding the trajectories of plumes. However, further validation studies are required, including comparison to observations as well as between models;

The meeting established a training sub-group to identify scientific material needed for inclusion in training in support of the IAVW;

There is no definition of a safe concentration of ash for different aircraft, engine types or power settings. In order to give a reliable and justifiable all clear once a plume has dispersed enough to be undetectable, clear limits of ash content are required from both the manufacturers and aviation licensing authorities.

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