No imminent ‘large aftershock’ threat

The multi region structure of Civil Defence showed it’s weakness again yesterday when West Coast Civil Defence warned people to prepare for a ‘large aftershock’, but this was talked down by the Ministry of Civil Defence and Geonet, who said their information had been misinterpreted.

West Coast Civil Defence have since retracted their warning.

Aftershocks are normal after large earthquakes. So far there have been over 5,000 aftershocks following the Culverden-Kaikoura-Seddon M7.8 earthquake on Monday last week.

6.30am update: 7 eq in last hour, 156 eqs in last 12 hrs ( only 2 over M4) and 5456 eqs since the M7.8 Kaikoura Earthquake – @Geonet

They seem to be following a normal pattern of reduced frequency and size with a few bigger  blips.

Geonet have made general predictions of aftershocks based on statistics, which includes the likelihood that there will be large aftershocks some time. But it is not possible to accurately predict how big, nor when.

Regardless of the uncertainty people throughout New Zealand should be prepared for any earthquake event.

Newshub: National Civil Defence says no imminent ‘large aftershock’ threat

West Coast Civil Defence Public Information Manager Andy Thompson earlier said the aftershock activity in the area been “suspiciously quiet”.

“The GeoNet seismograph drums have been very quiet for the last day or so and the normally higher aftershock sequence of large quakes has not been occurring in the Kaikoura area,” said a statement from West Coast Civil Defence.

West Coast Civil Defence regional manager Chris Raine said another worry is that an area in Arthur’s Pass slightly west of the divide has experienced a number of small tremors in the last few days.

He said it’s an area they have been monitoring closely, with Mr Thompson describing it as “highly sensitive”.

West Coast Civil Defence has staff on duty this weekend to be available in the case of aftershocks and the forecasted heavy rain that is expected to start tomorrow morning.

They are urging locals to stock up on enough food, water, cash and medicine to last a week, and to ensure they have an emergency plan in place.

“If an earthquake is so strong that people can’t stand up, or rolling lasts more than a minute, they should evacuate inland,” regional manager Chris Raine said.

 The problem isn’t with the advice, but with the warning of an imminent large aftershock in their region.

But GeoNet say the science they’re using to authenticate the warning is simply incorrect.

“Just because the drums have been quiet for a day means absolutely nothing,” GeoNet seismologist John Ristau said.

“We kind of want to distance ourselves from this – we don’t know why they’ve gone out and done this.”

Mr Ristau says it is not usually Civil Defence’s policy to issue a warning without checking in with them first.

“Civil Defence would talk to us, we advise them, and they would never release anything without talking to us.

“What [West Coast Civil Defence] have done is looked at our [seismograph] drums, and taken the information we’ve put out and made their own interpretations.”

The Ministry of Civil Defence’s head office was also bemused by what was put out by the West Coast offshoot when contacted by Newshub, with a spokesperson saying they’re not aware of any increased risk of a strong aftershock.

The spokesperson reiterated that they are in regular contact with GeoNet, and would seldom issue a warning without consulting them first.

@Geonet tweeted at 7:13 last night:

Reminder: We produce forecasts and scenarios NOT specific eq warnings regarding aftershocks. if you see an eq warning, it’s not from GeoNet

Followed by

Contrary to some reports the Ministry of Civil Defence has not issued an earthquake threat warning for West Coast

On Facebook yesterday at 7:18 pm::

Please share this with anyone you know who is worried.

Contrary to some reports there is no “imminent threat” to the West Coast from earthquakes. Neither have we issued an earthquake threat warning.

After a large earthquake there is always an increased likelihood of aftershocks, some of which may be large.

Remember: drop, cover and hold until the shaking stops.

If you feel a strong earthquake that makes it hard to stand up, or a rolling earthquake that lasts longer than a minute, or observe strange sea behaviour such as the sea level suddenly rising and falling, or the sea making loud and unusual should move immediately to high ground, or as far inland as possible.

Since Monday GeoNet have been issuing earthquake forecasts based on the best science they have available – their most recent one can be found here: http://info.geonet.org.nz/…/M7.8+Kaikoura+Quake%3A+Future+S…

 And they followed up at 22:05 pm:

On our previous post: West Coast Civil Defence Emergency Management have retracted their urgent warning around large aftershocks on the West Coast. Media ran their stories in good faith and we thank them for running clarifications.

Remember – after a large earthquake there is always an increased likelihood of aftershocks, some of which may be large. Check out our previous post for more advice on what to do in quake.

You can find the latest earthquake forecasts from the good folk at GeoNet

The disjointedness between Geonet, national Civil Defence and all the Civil Defence regions is messy and needs to be tidied up.

West Coast Civil defence have now retracted their urgent warning.

Stuff: Large aftershocks a possibility, but there are no ‘urgent warnings’

West Coast Civil Defence Regional manager Chris Raine initially refused to answer questions from the media about the release, saying he was not prepared but was dealing with the fallout with the ministry. 

From his home in Greymouth, he said he accepted people were concerned after the release was issued and apologised.

“I apologise. It was done in the best interests of the West Coast people,” he said.

“I withdraw the urgent warning completely.”

He added Thompson, who issued the release, may have “misinterpreted” the risk of aftershocks.

This is ridiculous. The only thing missing is a full moon.

Each local emergency management office was responsible for its region, Clifford said. The Ministry for Civil Defence was a “central coordinator” for emergency responses, she said.

“The West Coast have a responsibility for their community and they have acted in what they think is the best for their community,” Clifford said.

She urged people to follow the information and advice issued by GNS Science and the Ministry of Civil Defence.

“The press release that has come from West Coast was not sent on behalf of the ministry,” she said.

The current disjointed way that Civil Defence advises the public is hopeless. And poor.

The West Coast Civil Defence website gives no obvious indication of any of this, it seems to have all happened via media.

This is hopeless. Where should we look for up to date information and warnings on earthquakes? I have no idea.

The national Civil Defence website has general information but nothing specific. Their last News and events ‘new update’ is remarkably dated 10 November, before any of these earthquakes occurred.

We should all know exactly where to go online for the latest information and advice.

Leave a comment

3 Comments

  1. Gezza

     /  25th November 2016

    Good post PG. We do have no single source to go to – we should have. Sitting on the Ring of Fire with its complex dynamic geology, this country is significantly natural disaster-prone. Room for big improvement.

    Reply
  2. Alan Wilkinson

     /  25th November 2016

    Maintaining anything as sophisticated as a website is well beyond bureaucrats nowadays. They need contractors to do everything that matters. So if there isn’t a contract to do this there needs to be.

    Reply

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s