SciBlogs

Flooding and Landslides Pummel the top of the South Island Jesse Dykstra Dec 15

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Tourists stranded by floodwaters in Nelson.   Source: The Nelson Mail

Tourists stranded by floodwaters in Nelson. Source: The Nelson Mail

Rain-laden clouds from the north Tasman sea settled over the top of the south island several days ago, and have been drenching the Nelson and Golden Bay regions ever since. Extreme rainfall has been recorded in Takaka, Richmond and Nelson, with the Kotinga gauge at Takaka recordind an unprecedented 423mm in 24 hours. The estimated 24 hour rainfall for a 1-in-100 year event at Takaka is 380mm (Tasman district council here). The previous highest recorded 24-hour rainfall from the Kotinga gauge was 216.5mm in 1995.

Saturated hillsides have given way in many locations, with landslides and debris torrents reportedly causing widespread damage in the region (stuff.co.nz story here).

Flooding, Nelson.    Photo: Tim Bow

Flooding, Nelson. Photo: Tim Bow


Debris Torrent, Nelson.   Source: stuff.co.nz

Landslide, Nelson.     Source: The Nelson Mail

Landslide, Nelson. Source: The Nelson Mail


Flooding, Nelson.    source: stuff.co.nz

Flooding, Nelson. source: stuff.co.nz


Backyard Swimming Hole.   Source: stuff.co.nz

Backyard Swimming Hole. Source: stuff.co.nz

Fortunately, all the news is not bad, as the rain has been easing, with heavy precipitation moving towards the North Island, where Taranaki, Northland and the Bay of Plenty can expect up to 150mm of rain.

Flooded Hard-Drives and Hondas: Economic Implications of Thailands’ Latest Natural Disaster Jesse Dykstra Oct 28

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Flooding in Thailand     Source: thesun.co.uk

Flooding in Thailand Source: thesun.co.uk



Global Economic Hub
Thailand is a global manufacturing hub, and a leading exporter of automobiles, electronics, textiles, clothing and food. Exports of goods and services accounting for approximately 70% of Thailands’ GDP in 2010. Tourism has largely recovered following the Indian Ocean tsunami (which claimed more the 5000 lives in Thailand), accounting for about 6% of GDP in 2010.

Many of the world’s largest auto manufacturers have major factories in Thailand, including Toyota, Honda, Nissan and Ford. As the world’s largest manufacturer and exporter of hard-disk drives, Thailand hosts hard-disk giants Western Digital, and Seagate Technology. Sony, Toshiba, Apple and Canon also rely on their Thailand manufacturing facilities to supply the global demand for consumer electronics.

Worst Flooding in 50 years

Since flooding began in northern Thailand in July of this year, the country has been coping with another deadly natural disaster; one that will also have global economic implications. With a mean rainfall of nearly 800 mm for the three-month period from August to October, Bangkok is no stranger to flooding, but an exceptionally wet monsoon season in the north has brought the worst flooding in over 50 years. Swollen rivers and floodwaters have gradually made their way towards the south, threatening the most populated regions surrounding the bay of Bangkok. Thailand is a country of 67 million people, with an estimated 9 million living in the capital city of Bangkok, where much of the city is merely 2 metres above mean sea level. The immediate impacts of the disaster have only begun to materialize:

• nearly 400 lives lost to date

• more than 100,000 people displaced from homes

• one-third of the country inundated, including major agricultural and industrial areas

• damage estimates >$6 billion US dollars

As Bangkok braces for another day, 1.2 billion cubic metres of flood water is expected to peak around the same time as high tide. Government officials have thrown in the towel in the fight to contain the rising flood waters. As low-lying areas of the city become inundated, thousands of people continue to flee the capital for higher ground. Tourism officials issued travel warnings earlier today advising tourists that “flooding in Bangkok now appears imminent”. Indeed.

Submerged Cars at Honda Factory in Thailand

Submerged Cars at Honda Factory in Thailand


Global Economic Implications
It may be the long-term economic impacts of this disaster that are most damaging. Consumers around the world will soon face the consequences of the temporary crippling of Thailand as a global manufacturing hub. Only time will tell what the extent of physical damage will be in Bangkok, but the economic impacts are already beginning to mount. The Thai government has imposed a 5 day “weekend” to allow people to cope with the disaster, and production at many major companies has already been stalled for much longer than that. Toyota has had to keep its’ Thai production suspended for nearly 4 weeks so far, reducing its’ ability to supply the Asian, North American and South African markets. In turn, the loss of parts produced in Thailand has forced Toyota to slow down its’ operations in other countries, including Japan, the Unites States, and Indonesia.

Toyota is not alone. Many other manufacturing companies spanning a wide range of industries have been impacted by the flooding. The economic impacts of this disaster will soon be brought home to us all, in the form of decreased availability, and higher prices on many goods, including automobiles, electronics, clothing, and food.

As has been the case with many recent flood disasters (eg. Pakistan in 2010), this years flooding in Thailand may have been exacerbated by human activity (or inactivity in this case). Despite high precipitation in northern Thailand at the beginning of the monsoon season, some down-steam water storage reservoirs were not drawn down enough in the early stages of flooding, leaving less capacity for temporary storage of flood waters. But that is a topic for another post.

Front Row Seat to the Japanese Tsunami Jesse Dykstra Sep 30

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YouTube Preview ImageThe 11 March 2011 earthquake and resulting tsunami in northeastern Japan caused nearly 30,000 deaths and damaged over 125,000 buildings. The Pacific plate shifted by up to 20 m, over a fault-rupture length of 300-400 km. The tsunami waves caused by this displacement overwhelmed Japanese tsunami defences (some tsunami walls were over 10 m high), in part because coastal areas sunk by up to 2 m following the earthquake.

This video of the tsunami was taken by a dashboard camera in a car that was presumably abandoned on the road. It’s a different perspective. The currents & debris seem to swirl around and come from different directions, perhaps as new wave fronts conflict with receding waters. How terrifying, especially for those trapped in or on top of floating cars.

One Year On: Your Stories Jesse Dykstra Aug 31

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The Press/stuff.co.nz are running this site where anyone can tell their stories about how the Canterbury Earthquakes have affected their lives. Brave, battered, vulnerable people, sharing their stories in extraordinary times. Powerful stuff.

E for Effort: The EQC Report Card (Part 2) Jesse Dykstra Aug 30

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eqc.govt.nz

eqc.govt.nz

How Has the EQC Performed Following the Canterbury Earthquakes?

How would the EQC cope, when faced with the monumental task of managing nearly 400,000 claims from two major events in close succession? That was always going to be a tall order. Nearly one year on from the Greendale fault rupture, what can we say about the EQCs performance?

Unsurprisingly, the EQC has struggled to cope, and have been facing increasing criticism on several issues following the Christchurch earthquakes, including:
• withholding contractor payment for repairs (article here)
• length of time to process claims (article here)
• duplication of effort within EQC, and with private insurers
• lack of communication with homeowners and contractors

While I expect that the EQC had every intention of addressing the concerns raised in the 2009 review (see previous post here), I doubt that there was sufficient time, political will or funding to actually make any meaningful changes prior to 4 September, 2010. Not surprisingly then, many of the concerns raised in the review have come to fruition (my personal experiences relating to each point in italics):

 duplication of effort between the EQC and private insurers has caused major bottlenecks and delays. Some 80,000 claims have been delayed due to insufficient information provided by homeowners (nzherald.co.nz, 26 July). In many cases the repair estimates from private insurers and the EQC have not been in agreement, presumably because they have not worked together or shared information.
My personal experience:
- we have been assured by every assessor that has visited our home that we are over the $100k EQC cap. If that is the case, why wouldn’t the EQC just pay us out, and pass the claim onto our private insurer? Instead, both the EQC and private insurer are still individually going through their lengthy assessment processes and audits, rather than working as a team.

 Excessive assessments, inspections. Is it necessary?
My personnel experience:
- EQC: 3 “quick” assessments, 2 full assessments
- Private Insurer: 3 preliminary assessments, 2 full assessments, 1 flooring assessment
- Fletcher Building: 1 quick emergency assessment, 1 unsolicited visit for emergency repairs (repair work already done ourselves)
- Structural Engineer: 1 inspection
- CCC fire service: helped to remove badly damaged and unsafe chimney, thanks!
So, that’s about 14 inspections since the September earthquake, and we still haven’t had a stitch of work done other than what we’ve done ourselves, seen any resolution from EQC or our private insurance company, or even been told what to expect! We just want to get on with the repairs!

 Why aren’t some contractors getting paid? Stories persist of contractors going out of business as they struggle to get paid for EQC work. Insurance companies refuse to reinsure businesses, citing the risk of further damage to buildings from aftershocks. This is further crippling the rebuilding process (article here).
My personal experience:
- Our structural engineers report was submitted in October of last year, and as of last week they say they still hadn’t been paid for that work by the EQC.

 Communication: Very few people have actually been able to get any meaningful answers from the EQC. There isn’t any “shop front” where people can go and speak to a real person about their problems, instead they spend countless hours on the phone (mostly on hold), trying to get answers. In fact, the EQC brand isn’t anywhere to be seen these days, as the EQC logo seems to have been removed from most personnel and vehicles. Is this so that EQC workers don’t have to front up to an angry public? The other day I noticed an otherwise nondescript white car with two fellows aboard wearing high viz vests. In tiny black letters beside the registration plate was written “EQC 21″. How quickly the EQC has adopted a low profile in Canterbury.
My personal experience:
- Despite calling and emailing the EQC some 40 times, we do not seem to be any closer to resolving our claim. Each time we speak to a different person (of first name only), and never have we been assigned a “case manager” who understands and looks after our unique claim. We have been promised a return call or email by many of these well-meaning EQC people, but not one has ever actually followed through with that promise. Weeks, perhaps months of our lives have been dedicated to just trying to get answers.

 Claim Processing Time: what is an acceptable time frame? Is 6 months, or a year an acceptable time frame given the circumstances? Is it fair to take that long to process a simple contents claim, and still ask homeowners to hang onto high-value damaged items as proof of ownership?

In fairness to the EQC, it’s in all of our best interest for them to be thorough and fair when it comes to processing claims. We don’t want them to be wasting our premiums on fraudulent or unfounded claims. But there must be a balance between efficiency of settling claims, and scrupulous auditing, especially when resources are stretched to the limit, and the task at hand is so enormous. Shouldn’t the EQC be working with the insurance industry to streamline the claims process? Surely the cost of crippling the rebuild process will be far greater than a few missed audits. I hope that the EQC learns from this experience, and improves their efficiency for future major disasters.

What Does the Future Hold?
Business Woman Climbing a Pile of Files

As a homeowner in Christchurch, I have found the claims process to be frustrating. However, I accept that there are thousand of other people who have much greater issues than I. Homes can be repaired or rebuilt, but many others have lost family members or friends. As a Natural Hazards and Disaster scientist, I can appreciate that most of us are very fortunate indeed. It is clear that the Canterbury earthquakes are an opportunity to better understand and prepare for future large disasters in New Zealand. That opportunity extends to all of use, from the scientific community, to local and central government, and the general public. We can, we should, and we will be better prepared for the next major natural disaster in New Zealand.

Following today’s shocker announcement by the government that the Canterbury earthquakes are now expected to cost the EQC $4 billion more than expected, it is now apparent that the EQCs $6 billion reserve will be decimated. Just a few days ago it was reported that there would be around $2.5 billion of that reserve left, plus a further $2.5 billion of reinsurance for future events (article here). Todays announcement by ministers Bill English and Gerry Brownlee has increased concern about the long-term viability of the EQC’s Natural Disaster Relief Fund. Despite retaining a AAA credit rating, the EQC faces rising reinsurance costs, with all of their four primary reinsurance contracts due for renewal by the end of 2013, and this with effectively no assets to leverage, other than government gaurantees. This raises questions about how the EQC will replenish their coffers. Is an earthquake tax or levy the quickest way to build reserves back up to at least 2009 levels, so that the EQC has the capacity to cope with future major disasters?  Reserve levels should be restored relatively quickly – let’s not forget that an Alpine Fault or Wellington earthquake, a major volcanic eruption, or a tsunami could affect New Zealand at any time, and it’s always better to save up for a rainy day than to have to borrow to pay for it. So, it seems an inevitable consequence that our EQC levies will rise substantially, and I would be surprised if an earthquake levy isn’t on the cards. Perhaps the incumbent National government will wait until after the election to announce such a tax. But higher EQC premiums and tax increases are not all bad.

A Wonderful, Rich, and Active Land

The major economies of New Zealand, including tourism, dairy and mining are a direct consequence of living in this wonderful, active landscape. Our collective wealth was born of fertile valley bottoms and alluvial plains, rich volcanic soils, and abundant fresh and coastal waters. Our mountain ranges are uplifted by tectonic forces just as steadily as they are eroded and weathered by wind, rain and ice, bringing mineral wealth near the surface, where we can exploit them. Our varied and spectacular landscape facilitates one of the world’s most important tourism industries, despite our relative isolation. This active landscape is an important part of what makes New Zealand unique and special. Therefore it should come as no surprise when hazardous natural processes occasionally affect our lives, and we should prepare for those instances as best we can. I for one can accept higher EQC premiums or tax increases, knowing that we are preparing for the inevitable natural disasters of the future.

Where Would we be Without the EQC?

In other disaster-prone areas of the world, where publicly-owned EQC-equivalents do not exist, private insurance companies are reluctant to expose themselves to the additional risk associated with many natural disasters. Disaster insurance is therefore very limited, very expensive, or both. In California for example, natural disaster insurance can cost several hundreds to thousands of dollars per year, and commonly carries excesses of 10-20% of the insured value. That means paying an excess of $20-50k or more in the event of a major disaster, consequently many homeowners choose to bear the risk themselves and forgo natural disaster insurance altogether.

The inadequacies of relying on non-disaster-specific insurance in disaster-prone areas was clearly evident following the costliest natural disaster in US history, 2005’s hurricane Katrina (over 1300 dead and US $108 billion damage). The majority of homeowners in the Gulf region did not carry separate flood insurance, and the insurance industry declined many claims on the basis that damage was caused by flooding, rather than by wind or wind-driven rain. The resulting anger, fear and uncertainty amongst those hundreds of thousands of people without flood insurance was finally addressed with an unprecedented disaster-assistance payout by the US federal government.

Here in New Zealand, we thankfully have some certainty. Homeowners have been paying into the EQC pot for decades, spreading out the financial impact of a future major disaster. That “rainy day” has finally come, and the Natural Disaster Fund is being called upon. Despite all the headaches of dealing with insurance claims, and the slow pace of assessments and claim settlement in Canterbury, I am very glad that we at least have some peace of mind, knowing that the EQC is there. Let’s hope that New Zealand’s EQC remains strong and committed to responding to natural disasters in the future, and that we all learn from and build upon the lessons of this past year.

E for Effort: The EQC Report Card (Part 1) Jesse Dykstra Aug 30

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EQC_assessMARTIN DE RUYTER/The Nelson Mail

Perhaps it’s a good time to give the EQC a preliminary grade on their performance following the Canterbury earthquakes. After all, New Zealand homeowners pay EQC premiums every year to help ensure that our communities are able to recover from natural disasters. So, has the EQC met the expectations of the public that they serve? And are those expectations realistic, given the limited size (only 21 regular full-time employees) and resources of the EQC?

Who are the EQC? What do they do?

By now, many New Zealanders will be well accustomed to what may be the most-uttered acronym in New Zealand, EQC.

EQC was established in 1945 by central government to “provide earthquake and war damage cover for purchasers of fire insurance” (eqc.govt.nz). For nearly 50 years EQC premiums have been collected from residential property owners to build up the Natural Disaster Fund, which reached a pre-Canterbury Earthquake value of nearly $6 billion. During that time the EQC scheme has evolved, adding cover for other natural disasters, including landslips, volcanic eruptions, tsunami, storm, flood, and geothermal activity, and removing cover for war damage. In its current state, EQC cover protects residential property owners to a maximum of $100,000 (plus GST) for buildings and land under buildings, and $20,000 (plus GST) for contents.

The modern EQC is a small Crown entity which is governed by a board of commissioners appointed by the Minister of Finance. The EQC reports to the Minister through the national Treasury, and operates under its own act of Parliament, the Earthquake Commission Act (1993). The Act ensures that in a major natural disaster, the EQC will invoke its Catastrophic Response Programme (CRP), which is a detailed plan for accessing and mobilizing the resources that will be required during such a time, including additional staff and equipment.

The 2009 Review of EQC’s Response Capacity

The EQC’s capacity to deal with a significant disaster was recently reviewed independently by a panel of external specialists, led by retired General Peter Cosgrove of the Australian Defence Forces, and Karen Stephens, former emergency manager for Wellington City Council. That review was published in May, 2009 in a 32-page document entitled “Review of EQC’s Catastrophic Response Capability” (here). The report noted that during normal times (i.e. when the CRP is not in effect) the EQC has a total staff of only 21 persons. The report also noted that while the EQC may be called upon in a major disaster to respond to up to 150,000 claims, to date it managed events of up to 6000 claims only (i.e. the 2007 Gisborne earthquake). The 150,000 claim “worst-case scenario” was based on a future Wellington Earthquake. Prior to 2010, the EQC had performed well in its response to disaster events, but those events were one, or even two orders of magnitude smaller (at least in terms of claim load) than what was expected in a “major disaster”.

Here are just a few of the recommendations put forth by the panel in 2009:

• reduce duplication of effort in processing and claims approval between EQC staff, support services staff in Brisbane, and private insurance companies.

• government guidance on acceptable claim processing times.

• establish a “shop front” early after a major event, where people can obtain information and lodge claims.

• improve public communication.

• streamline audit process for claims.

• share resources with the insurance industry and eliminate duplication of claims processing, multiple call centres, multiple assessments and inspections, etc.

• develop relationships with engineering firms who can inform EQC loss adjusters on whether or not full engineering inspection/reports are required.

• consider providing training and other support for recently retired professionals who could quickly supplement loss adjustment staff.

The Reality Check: 2010/11 Canterbury Earthquakes

By now we all know that New Zealand experienced its first major disaster of the EQC era on 4 September, 2004. Nearly 157,000 claims were lodged with the EQC after the September earthquake, followed by a further 156,000 claims resulting from the aftershock of 22 February 2011 that devastated much of Christchurch’s CBD, and heavily damaged the eastern and southern suburbs. That’s a total of 390,000 claims (and counting), or nearly 65 times the number of claims from the previous largest disaster that the EQC has faced, the 2007 Gisborne earthquake.

CanterburyClaims
See Part 2 for continuation

The Press – Summary of Canterbury Earthquake Situation Jesse Dykstra Jun 21

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I really appreciated this article by John McCrone of the Press. It’s clearly written, summarizes much of the information to date, and considers the scientific perspective as well as that of the overall community.

Article here:

Christchurch no More Risky than Wellington. But Does That Make a Good News Story? Jesse Dykstra Jun 01

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Wellington Faults.  Source: GNS Science

Wellington Faults. Source: GNS Science

CERA Meeting Scares Media

Some media outlets have put a rather negative spin on GNS Science’s most recent earthquake forecast for the central Canterbury region, which was discussed at a recent meeting of the Canterbury Earthquake Recovery Authority (CERA). GNS’s latest forecasting model estimates the probability of a “large” (magnitude 6.0 to 6.9) event occurring within the region over the next 12 months to be 23%, dropping to 10% over the following year.

The forecast figures provoked a bit of a media feeding frenzy. “Strong chance of another big shake” trumpeted the New Zealand Herald yesterday morning. “Big earthquake risk put at 23 percent” read yesterdays’ headline on Stuff.co.nz. Clearly such headlines are not good for the progress of Christchurch’s recovery, or indeed for the nation’s $9 billion tourism industry. Enticing overseas visitors to a damaged city is hard enough without telling them that there is a 1 in 4 chance of another major quake in the next year. Christchurch Mayor Bob Parker was forced into damage control mode, claiming on TVNZ that GNS’s forecasting figures have been taken out of context.

Hazard is Not the Same as Risk!

There is clearly some validity to mayor Parker’s claim. In the scientific sense, GNS’s figure of 23% does not relate directly to “risk”, as portrayed by some media outlets. The probability of a large earthquake occurring somewhere within the model area within the next year is 23%. That simply reflects the regional hazard, which is very different than the risk to the largely urban population. The risk associated with a natural hazard is nearly always highest where the hazard intersects with population centers. So if we are actually going to talk about risk, we should be looking at the probability of another large earthquake occurring very close to Christchurch (or Wellington for that matter).

Adding Fuel to the Fire

Unfortunately, the media haven’t done a great job of informing the public of what the GNS forecast means in terms of risk, and have arguably succeeded in generating unnecessary fear and anxiety. Those sentiments are clearly evident in the comment stream on Stuff.co.nz, which include:

” I appreciate getting this info. although I feel quite down about it. I would rather know than not know. Now we can make decisions about whether to stay here or not. At this stage I,m thinking of moving away for a year or so, just to see what pans out. I have been on edge since Sept. 4th. + don,t really fancy living another year like this.”

Which sums up the emotional state of many residents of Christchurch and surrounding area, who are tired of waiting for the aftershocks to end. Tired of waiting for information on EQC and insurance claims. Wondering if homes will survive the next big aftershock. Wondering if it makes sense to stay in the Christchurch area. Many Cantabrians are on edge. But is the negative press actually justified?

What Does the Science Actually Tell Us?

Let’s take a closer look at the GNS figures, and ask:

What is the science actually saying about the future risk of another large earthquake in the greater Christchurch region?

One needs to put the GNS figures in the correct context, which means acknowledging that the GNS model calculates the probability of future earthquakes in the entire post-4-September aftershock area, which covers roughly 10,000 square kilometers of the central Canterbury plains and Banks Peninsula. The aftershock area encompasses Christchurch City (including the former Banks Peninsula District), and large portions of the Waimakariri and Selwyn Districts. In terms of population, approximately 460,000 people live in the area encompassed by GNS’s forecast, with some 370,000 (or 80%) of those people living in Christchurch City. By my very rough calculations, the urban area of Christchurch City is approximately 200 square kilometers, a small fraction of the area that the GNS forecasts cover.

Source: GNS Science (aftershock area boundary and urban area added)

Source: GNS Science (aftershock area boundary and urban area added)

Even if we consider the broader Christchurch City area to be 25% of the overall GNS forecast area, then we are more realistically looking at a 1 in 20, or 5% chance of a similar event to 22nd February occurring again in the next year. How does this compare to other urban areas in New Zealand? According to GNS scientists,

“What we’ve actually calculated is the 23% probability for the entire aftershock region. So that’s looking much beyond Christchurch.
We don’t really have any specific way to narrow that down to Christchurch, but as a kind of guide based on some basic information, that’s roughly a quarter of that probability. In rough terms, it means the quake probability for Chch has become similar to many other parts of NZ such as Wellington, Hawke’s Bay, Wanganui, and Poverty Bay where quakes are more frequent.” (M. Gerstenberger and J. Callan, GNS).

“Turn it around the other way, there’s a 95% chance that nothing will happen and I think that is the space that I would rather exist in than sitting around going ‘there’s a 5% chance it will happen in my city” (Christchurch Mayor Bob Parker)

So, based on GNS’s latest forecasts, Christchurch’s earthquake risk in the near future is similar to that for other seismically active urban regions in New Zealand. The 22 February earthquake caused so much devastation in Christchurch (even though it was within the realm of aftershocks that were expected following 4 September), because it unfortunately occurred very near the highest density of population and infrastructure. Could this happen again? Yes, it could, but the chances are much less than 1 in 4, and probably no more likely than than a similar event in Wellington.

Where Would the Fault Lie?

It is also important to note that it takes a significant fault to generate an earthquake of M 6-6.9. Such a fault would have to be at least as long as the Port Hills fault, and/or connected to other faults that could rupture at the same time. Computer models simply cannot tell us definitively whether or not that is the case. We need to know conclusively if such a scenario is possible, and if so, what the risks are. Which is why scientists are currently working very hard to generate a better picture of the faults and past seismicity of the greater Christchurch region. This work includes subsurface geophysical investigations, which can be focused on certain priority areas based on the distribution of aftershocks following the 4 September earthquake. Such areas include the oft-mentioned “gap” between the Greendale and Port Hills faults. Some media stories have led concerned people to believe that a fault in the gap “may rupture and link the two bigger faults” (Stuff.co.nz, 31 May, 2011). This is somewhat misleading, as the two bigger faults have already ruptured, so even if a connecting fault in the gap ruptured in the near future, most of the potential energy from the longer end sections has already been released. Furthermore, the highest density of aftershocks has been in the gap, suggesting that much of the energy there has also been released. Of course, that does not preclude the possibility of other faults near Christchurch, a question that current and future scientific investigation will help to resolve.

Vast amounts of data have already been collected, and leading scientists are processing and interpreting that data now. These data will represent one of the most extensive pre-to-post earthquake data sets in existence. In the near future we will have a better idea of the earthquake history, and fault distribution and connectivity in central Canterbury. In the meanwhile, New Zealanders, as a matter of course, should be preparing for future earthquakes. We live on a plate boundary, and Christchurch will not be the last place that is affected by earthquakes.

Canterbury Earthquake Update: Aftershocks ‘exactly what we expected’ Jesse Dykstra Jan 27

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untitled

Source: The Press

In a recent Press Opinion piece, earthquake and tectonic expert Dr. Kevin Furlong explained the distribution of aftershocks following the Darfield earthquake, and why we shouldn’t be surprised by what we have learned, and felt, so far. His article can be viewed by clicking the following link:  Dr Furlong, Opinion piece.

Kevin Furlong is a Professor of Geosciences at Penn State University, and is currently a visiting Erskine Fellow at the University of Canterbury. Dr. Furlong was in Canterbury on the 4th of September, 2010, and was one of the first scientists in the field after the magnitude 7.1 earthquake. Dr. Furlong’s public lecture after the earthquake was attended by hundreds of people, as was a subsequent lecture by University of Canterbury Geological Sciences Professor Dr. Mark Quigley. Both lectures may be linked here:

Queensland Flooding: “Australia’s Worst Natural Disaster” Jesse Dykstra Jan 12

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Toowoomba1

Flash Flooding in Toowoomba. Source: Reuters

 

Queensland Premier Anna Bligh and Australian Prime Minister Julia Gillard have called the recent flooding in Queensland the “worst natural disaster in our history”. Three-quarters of the state of Queensland has been declared a disaster zone (source: Brisbane times). Flooding has affected over 200,000 people in the Fitzroy, Burnett, Condamine, Mary and Brisbane river basins (flood map here). A total of 41 deaths have so far been attributed to the flooding, and 67 people remain missing.

The worst flooding of the last 48 hours has affected the Brisbane river basin. Toowoomba. Grantham. Ipswitch. Brisbane. Each community in turn has borne the brunt of floodwaters from the Lockyer valley, with flood levels exceeding the great flood of 1974. Flash flooding in Toowoomba quickly inundated the town, catching many by surprise, and killing 10 people who were swept away by the fast-moving flood waters (video here). Over 40 people were plucked from rooftops by military helicopters, and search and rescue crews continue to search for missing people.

The Lockyer is a major tributary of the Brisbane river, which also continues to rise, and is forecasted to exceed the 1974 flood level of 5.5m some time tomorrow. With the lower Brisbane river continuing to rise, flooding is expected to peak tomorrow (Thursday, 13 January) in Brisbane. The latest flood models suggest that as many as 20,000 properties in Brisbane may be entirely flooded. Thousands of people have been evacuated, and many more face evacuation.

The level of the lower Brisbane river can be controlled to a degree, by modulating the release of the Wivenhoe dam, which is (at the time of writing) at around 190% capacity, and holding back more volume of water than Sydney harbour. The Wivenhoe dam was constructed following the disastrous floods of 1974, when 14 people lost their lives and 8500 homes were flooded in Brisbane and Ipswitch. This time, nervous flood modellers and dam engineers must try to strike a fine balance between spilling too much water from the dam (and exacerbating an already bad flooding situation in the lower Brisbane river valley), and holding back too much water, which could eventually cause the lake to overtop the dam. We will likely find out tomorrow or the next day if the right decisions were made.

389933-queensland-flooding-disaster

Source: Reuters