Jesse Dykstra

The Alpine Fault: Is New Zealand Prepared? - Shaken Not Stirred

Nov 20, 2013

The central section of the Alpine Fault (Source: This post is the first of two articles which explore the potential impacts of the next great earthquake on the Alpine Fault and consider how prepared New Zealand is for that event.  This builds on a previous post which describes the physical properties of the Alpine Fault in more detail. Improved Understanding of Earthquake Hazards in New Zealand Damage in Christchurch following the 22 Feb. 2011 earthquake One of the positive outcomes of the Canterbury earthquakes of 2010 and 2011 is an increased focus on improving our understanding of earthquake risk in other seismically active regions of New Zealand,  including the Wellington area, and the West Coast of the South Island, where our largest and most active fault, the Alpine Fault, is due to rupture. The imminent rupture of the Alpine Fault is a subject which has recently … Read More

Typhoon Haiyan: how does it compare? - Shaken Not Stirred

Nov 13, 2013

(note dates as of 8 Nov. 2013)   The Guardians’ Ami Sedghi has written a nice blog comparing Typhoon Haiyan, which has caused devastating damage and loss of life in the Philippines over recent days, to historical tropical storms;  Haiyan has been widely reported in the media as one of the largest tropical storms in history. Ami has also clarified the use of varying names for tropical storms (e.g. typhoon, hurrican, cyclone), depending on where they are.  Turns out that Haiyan looks like the fourth strongest tropial storm in history, and the strongest where it made landfall. Thanks Ami! … Read More

Could Wellington be Next? - Shaken Not Stirred

Jul 22, 2013

Recent Seismic Activity Beneath Cook Strait Over the past three days, earthquakes have been rattling central New Zealand, with the epicentres of many of the tremors between Seddon and Wellington. According to GNS, the largest earthquake had a magnitude of 6.5, and was located beneath Cook Strait at a depth of 17 km, some 55 km from Wellington, and 45 km from Blenheim. There have been several dozen significant aftershocks, leaving some residents fearing that the recent seismic activity could be a precursor to a much larger earthquake in central New Zealand. Recent Earthquake activity (accessed 22/07/2013 12:30am)Source: GNS Wellington and the Marlborough Fault System Normally, when seismologists talk about a future earthquake in Wellington, they … Read More

Alpine Fault 101: Getting acquainted with New Zealand’s greatest natural hazard - Shaken Not Stirred

May 28, 2013

Modeled Earthquake Shaking Intensities for New Zealand. Zone of maximum shaking along Alpine Fault indicated by red band.Source: The Alpine Fault will rupture in the near future (quite possibly in your lifetime), without any prior warning. When it does, the scale of the immediate disaster will be unprecedented in New Zealand, and secondary effects will probably continue for decades. The Canterbury earthquakes of 2010 and 2011 served a brutal reminder of how vulnerable we are to strong ground shaking, so perhaps now is the perfect time to collectively improve our understanding of our greatest seismic hazard, and to prepare and build resiliency in vulnerable communities. What is the Alpine Fault? The collision of two great tectonic plates is building up strain along New Zealand’s Alpine Fault, which traces the western flanks of Southern Alps. The Alpine Fault … Read More

Cruel Irony in EQC Privacy Breach: information on 83,000 claimants leaked - Shaken Not Stirred

Mar 27, 2013

As widely reported in the media yesterday, details of EQC claimants and claims have been leaked in a privacy breach that effects 83,000 Christchurch households. That’s details of every claim between $10-100k, arising from the 4 September 2010 and 22 February 2011 earthquakes. The leaked spreadsheet included details of EQC repair cost estimates and associated contractor quotes. If this information gets into the hands of building contractors or other rebuild stakeholders, the ability to obtain a fair settlement could be compromised for many claimants. For example, if Fletcher Building (who are managing most of the leaked claims) gets their hands on the EQC numbers, then any incentive for Fletcher to manage repairs in the best  interest of the claimant, rather than EQC, could be lost. Despite the potential ramifications of such a massive breach of sensitive financial information, EQC boss … Read More

Climate change complicit in scorching heat, bushfires, flooding and tornadoes of disastrous Australian summer - Shaken Not Stirred

Jan 29, 2013

From a natural disaster perspective, Australia is having a much worse year than New Zealand, despite our apparent penchant for earthquakes, volcanic eruptions, flooding, and the occasional crippling winter storm on this side of the ditch. To date, the Insurance Council of Australia has officially declared three natural disasters in 2013 (the Tasmanian bush fires, New South Wales bush fires, and cyclone Oswald). But is Australia’s exceptional season for extreme weather just a blip on an otherwise “normal” climate regime, or is it perhaps a harbinger of worse things to come as our climate continues to warm? Worse than the Queensland flooding of 2011? Our poor neighbours across the ditch have been enduring scorching temperatures and raging bush fires for nearly a month, and now the east of the country is being thrashed by extreme weather, this time … Read More

Spectacular Footage of Yesterday’s Tongariro Eruption – Risk Remains High - Shaken Not Stirred

Nov 22, 2012

Mount Tongariro Eruption. Source: TVNZ A Geonet webcam at Mt. Tongariro has captured spectacular footage of yesterday’s eruption, which lasted approximately 5 minutes, ejecting an ash column and plume some 3-4 km above the Te Maari crater. There have not been any reports of injuries or damage, beyond a light dusting of ash falling near the volcano. The volcano burst into life again yesterday without any warning; seismic monitoring stations near the vent recorded no activity before the eruption. Tongariro has been returned to an Alert Level 2 (i.e. minor eruptive activity), with an aviation colour code of orange (minor ash ejection). Since yesterday’s eruption (the first since 16 August; that eruption was from the same vent) activity has been low, but GNS scientists believe that the risk of further eruptive activity remains high, with a significant probability … Read More

Mount Tongariro eruption – sleeping giant awakens - Shaken Not Stirred

Aug 07, 2012

Seismic signature of Tongariro eruption. GeoNet Last night Mount Tongariro burst into life, erupting for the first time in over 100 years. The eruption raised the Geonet volcanic alert from level 1 to 2, with an accompanying aviation colour code of red. The Tongariro alert level had been upped to level 1 on 20th of July 2012, due to increased seismic activity and other signs of volcanic unrest.  However, according to GNS volcanologist Michael Rosenberg, last night’s eruption was still a surprise, as seismic activity under the volcano appeared to be on the decline in recent days.  He warned that although the volcano seems relatively quiet at the moment, this early in the eruptive sequence it is impossible to know whether Tongariro’s activity will escalate in to a full-scale eruption. According to GNS science, Tongariro is a … Read More

Flooding and Landslides Pummel the top of the South Island - Shaken Not Stirred

Dec 15, 2011

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 ( story here). Flooding, Nelson. Photo: Tim Bow Landslide, Nelson. Source: The Nelson Mail Flooding, Nelson. source: … Read More

Flooded Hard-Drives and Hondas: Economic Implications of Thailands’ Latest Natural Disaster - Shaken Not Stirred

Oct 28, 2011

Flooding in Thailand Source: 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, … Read More