OPS: And The Earth Shook...
by Bob Gough, Asia-Pacific Contributing Editor
Have you ever been in an earthquake? I have, once, and its terrifying. Not a powerful earthquake, admittedly, and most California residents would probably have called it a tremor. However, it was enough to cause me to wake me up in the middle of the night, in the dark, and my first thoughts were, Why does it feel like my head is spinning? Did I really drink that much vino rosso with my bistecca di manzo dinner at Umbertos Ristorante?
Only after turning on the bedside light in the hotel did I realise that it was my head that was spinning, as was the chandelier in the center of the ceiling. Thats when the fear hit me...
I was in the town of Avezzano in the Abruzzi region of the Apennine Mountains in Italy, some 120km east of Rome. That in itself was no cause for concern, but remembering that Avezzano was totally destroyed by an earthquake on January 13th, 1915, with 32,610 deaths (96 percent of the population) had me shooting out of the bed, flying down the stairs, and out into the street.
I wasnt the only person exiting the Hotel Principe half-dressed and half-asleep, so perhaps what was experienced was more than a simply a mere tremor.
This happened in the late 1970s while I was working for the European Space Agency (ESA). At that time I was responsible for the in-orbit testing of the transponders of the OTS satellitethe satellite control and test station (SCTS) was hosted by Telespazio at their Fucino Earth station complex. Avezzano was the nearest town to the Earth station and about 16km northwestI spent most of a two year period in Italy at this location.
I cant remember whether I returned immediately back into the hotel to grab car keys, a shirt and trousers, but it wasnt long before I drove to the Fucino Earth station to see if all was well. I was concerned because the Conca del Fucino used to be a very large lakein fact, in Roman times, sea battles involving large ships, sacrificial slaves, and gladiators were played out on the lake to entertain the populace and the Emperor of that time.
Over the centuries, numerous attempts were made to drain the lake (hundreds of slaves drowned in the early attempts)eventually, the Dutch succeeded and completed the job.
The reason I mention this (fascinating in itself) history is because the pancake-flat Conca del Fucino (now the largest potato growing area in Italythe patchwork of fields is clearly visible on the map) is made up of silt; to a depth of heaven knows how many metres. Anyone whos watched Nat Geo or Discovery Channel on TV will know that earthquakes and silt soil do not go well together!
When I arrived at the Earth station everything looked normal, so at least the antennas hadnt disappeared into the depths of liquefaction! I thought Id better check the telemetry to see how the spacecraft was doing and everything looked normal, including the AOCS (Attitude & Orbit Control System). My next check was the Earth station antenna tracking status and this is where a bit of technical background is needed. Dont get put off, because this is where the story gets interesting.
OTS was one of the first 3-axis stabilised geostationary satellites (ATS-6 was the first) and was the first satellite to carry 6 Ku-band (12/14GHz) transponders. The main SCTS Earth station antenna we were using at Fucino was a custom-built 13 metre Cassegrain dish, and AEG Telefunken was the prime contractor. This had a 3dB beamwidth of 0.15 degrees at 11GHz, but we needed a real-time tracking accuracy of much better than +/-0.005 degrees.
There are basically three types of tracking systems one can use; program track, step track, or monopulse. For a testing application where accuracy is paramount, SCTS was equipped with a monopulse system. This technology is used for extremely accurate tracking of fast moving objects, be they missiles or satellites. In essence, its an extremely sensitive closed-loop control system so the pointing of the Earth station antenna in Az (azimuth) and El (elevation) immediately follows even the slightest movement of the spacecraft.
I looked at the tracking log file for OTS for the previous few hours. The graph of the Earth stations Az & El pointing angles should have been gentle sinusoids of +/-x degrees, with a 24 hour period reflecting the satellites daily figure-of-eight movement within its 50km cube station-keeping box.
What I saw stopped me dead in my tracks; the Az and El plots looked like the output of a seismograph. Both Az and El exhibited massive positive and negative spikes around their nominal values; first one burst of them, then another, then another. Only then did it dawn on me that what I was witnessing wasnt the satellite movement at all, it was the movement of the antennas foundations in the lake-bed silt during the earthquake. The rapid response monopulse tracking system was compensating for the movement of the foundations and was trying to keep the pencil-thin antenna beam locked onto the satellite in its geostationary position some 36,000km above the equator. I had just stumbled upon the ultimate seismograph!
Can you imagine what it must have been like in Avezzano on that fateful morning in 1915? Rome was many hours away by horse, as was Pescara on the Adriatic coast. What were the communications liketelegraph, perhaps? The earthquake was felt in Rome but how long did it take to send help and assistance to the few survivors of the quake?
Now travel 45km north of Avezzano and wind the clock forward to 3:23 a.m. on April 6, 2009. This is the moment when the town of LAquila was struck by a 6.3 magnitude earthquake which killed more than 300 people and destroyed thousands of buildings. This whole area is earthquake prone, but what sets the LAquila earthquake apart from most others is the recrimination which ensued over the warnings (or lack of them) issued by authorities. The deputy head of the technical division of Italys Civil Protection Agency and six other Italian earthquake experts, including the then-president of the National Institute of Geophysics & Vulcanology, as well as the director of the National Earthquake Centre, now find themselves on trial for manslaughter!
The American Geophysical Union has warned that the trial will have long-term consequences for seismology, harming international efforts to understand natural disasters and mitigate associated risk.
Another major earthquake caused massive devastation in Sichuan, China, in 2008. It killed an estimated 68,000 people and left more than five million people homeless. Approximately 375,000 people were injured and more than 18,000 people were listed as missing. The epicentre of this magnitude 7.9 earthquake was 80km west northwest of Chengdu, the capital of Sichuan province.
It is pure coincidence that I happen to know someone who was in Chengdu with her husband when the earthquake struck at 2:28 p.m. on Monday May 12, 2008. She is the well-known writer Junying Kirk, author of The Same Moon and Trials of Life. Her husband, John, was one of the few western eye-witnesseshis testimonies were to appear in various U.K. newspapers, and his voice was broadcast via radio.
Initially, the mobile phone system was down and it was not until the next day the phone calls started coming in from Fox News, CNN, and others. When the inevitable questions about the effectiveness of the first response came in, here is his verbatim response...I think the Chinese government have reacted promptly and efficiently. Their Prime Minister was on the scene already, and as I speak, I can see Army lorries passing by our hotel window, no doubt heading towards the disaster area, doing rescue work. Compared to what happened when Hurricane Katrina hit New Orleans, Id say that the Chinese are doing a good job
The Ring Of Fire
There are many earthquake-prone regions of the Earth but one of the most widely known is the Pacific Ring of Fire, associated with the subduction zone of two tectonic plates and stretching thousands of kilometres from Alaska to New Zealand.
I hardly need mention the Fukushima earthquake and resulting tsunami. Earthquakes are occurring continually all along and close to this highly unstable geological band. For example, as I was writing this column, I noted a Twitter alert that a magnitude 7.1 earthquake had occurred under the ocean 124km west of Port Vila, the capital of Vanuatu, on February 2nd. Vanuatu, like most of these Pacific islands, are volcanic and exist only as a consequence of their location on the ring of fire.
As we go to press, news is filtering out regarding a magnitude 6.7 killer earthquake which hit the central Philippines on February 6, 2012.
Sometimes, though, even the most quiescent locations receive a totally unexpected shock, with devastating consequences. Im thinking in particular of Christchurch, New Zealand. In terms of first responders and how such a crisis is addressed in those first critical hours, who better to comment than Mr. John Hamilton, Director, Civil Defence and Emergency Management, Government of New Zealand. Here are Johns own words as he communicated them to me.
The earthquake struck Christchurch at 12:51 hours on February 22, 2011. It was the lunch hour on a fine and warm afternoon, with many people in the CBD at work and children at school. Initially, the cellphone networks were overloaded, probably through a combination of high traffic and some sites being damaged. In addition, electricity was disrupted across the city, which also impacted telecommunications. As reports of the scale of damage and number of casualties became available to the Government and officials in Wellington, it was clear the impact of this earthquake was something we had not experienced in New Zealand since the 1931 Hawkes Bay earthquake. On the morning of February 23rd, the Government declared a state of national emergency which put in place a National Controller with the authority to co-ordinate and control national resources assigned to the response. In those first few hours New Zealand received generous offers of assistance from Australia, the U.S., Singapore, China, the United Kingdom, Japan and Taiwan, and many others.
Surprisingly, the cellphone networks were re-established very quickly after the shock, albeit with a reduced capacity and, while electricity distribution took much longer to come back on, the use of back-up batteries and portable generators greatly assisted the telecommunications system. The lesson seems to be to encourage telecommunications providers to invest in redundancy, alternate power supplies and facilities that will better withstand the impact of a large earthquake.
On reflection it could be argued we were lucky in Christchurch. The central business district was hit hard with many collapsed buildings, injuries, and casualties. The eastern suburban areas were hit hard by liquefaction, and the southern suburban areas suffered significant rockfalls. And yet, large parts of the city suffered comparatively minor damage. Access to the city by air, road and sea was quickly restored and critical supply lines were open. It could have been much worse. Satellite communications were held by the emergency services and the citys civil defence emergency management office. But, it seems, satellite communications were for the most part held as the alternative means of communications and the primary means of communications used was the more traditional radio networks and cellphones.
As the National Controller for the emergency, I found that in the early stages of the response it was difficult to establish situational awareness, which in turn impacted our ability to set operational priorities. I attribute this to the combined effect of the highly valuable all hands to the pump initiative in those first critical hours, difficulties for first responders to then re-assign units, communications difficulties and demand for assistance across the city exceeding supply available. A formal review process is underway to draw out lessons which should improve readiness and the response and recovery to a future event.
There are many international, national and local organisations that are focused on the planning and execution of first response efforts, too many to do them all justice in this short article. Having said that, there are two international organisations that do warrant mention here. One is the International Atomic Energy Agencys (IAEA) RANET (Response and Assistance Network). The other is the United Nations UN-SPIDER Platform for Space-based Information for Disaster Management and Emergency Response.
A PDF file describing RANET can be found here:
UN-SPIDER (http://www.un-spider.org) has developed a Space Application Matrix which allows users to explore the possibilities of using space technologies for disaster management in all phases of the disaster cycle: mitigation, preparedness, response and recovery. This is an interactive, online portal with a very easy-to-use, intuitive method of finding the right documents from a large library of information.
With this tool you can access case studies and the Space Applications Guides, authored by experts and practitioners. These describe experiences from the application of space technology, and address benefits, lessons learned, and much more. Use the live tool at http://www.un-spider.org/space-application-matrix to see how powerful it is.
What To Do In The Event Of An Earthquake?
I started this article with a description of a personal experience, so it is fitting to end in the same vein. What should one do when the swaying starts and the shock hits? The conventional wisdom would appear to be Duck, cover and hold.
However, in recent years a different approach has been proposed by a Mr. Doug Copp, a veteran of a number of first line response rescues. His approach is quite different and gave rise to the term The Triangle of Life.
This has caused enormous concern and controversy and is hotly debated by various experts, experienced people, and organisations. Personally, I have no idea what is best, but for those readers who are interested, I suggest that you undertake an Internet search for Doug Copp and follow the numerous links to form your own view. Wikipedia also offers a good insight into this approach.
References and Citations
Theres an amazing collection of 34 photos of the aftermath of the 1915 Avezzano earthquake which can be found by a search in the U.S. Geological Survey (http://www.usgs.gov) archive. These were donated by family members of the late Admiral J. Lansing Callan, U.S. Navy Reserve. The monochrome photos included in this article are his and are copyright©.
Courtesy and copyright© Telespazio for the Fucino Earth station photo.
Courtesy and copyright© European Space Agency (ESA) for the OTS pictures.
Thanks to Junying & John Kirk (http://www.facebook.com/pages/Junying-Kirk/180846635299025) for permission to share their Chengdu experiences.
Courtesy and copyright© New Zealand Government Civil Defence & Emergency Management website for the Christchurch photographs: http://www.civildefence.govt.nz/memwebsite.nsf.
About the author
Bob Gough has spent more than 35 years in the satellite communications business and has experience in most aspects of SATCOM, which also happens to include seven years with the European Space Agency (ESA) in a number of roles, from end-to-end communication system design to work on the OTS, ECS, and OLYMPUS satellites. Upon leaving ESA, Bob was one of the first six staff members of Filtronic Components, which specialized in the critical microwave subsystems for naval and airborne EW applications. Bob was instrumental in opening up the U.S. market for the company. He then founded a successful satellite communications equipment manufacturing company, Communication Systems Research (CSR), which had an international customer base and specialized in antenna tracking systems, UPPC systems, digital modems, spread spectrum and CDMA systems, VSAT systems and Earth stations operating up to Ka-Band. Bob founded Carrick Communications Ltd in 1990 and the company offers consultancy, training and software applications for satellite communications. More detail regarding Bobs specific experience can be found on the Experience pages of his personal website: http://www.satellitespy.net, or at http://www.carrickcom.com.