This time last year, scientists knew more than they were telling us ... what else might the authorities not want a traumatised population to know?
Looking back over the year's newspapers this week I noticed a front-page item published in October and quickly forgotten, probably because it appeared four days before the Rugby World Cup final.
"Warning kept from frightened quake city," it was headed. "Scientists tell inquiry they knew a big one was coming."
As recently as last week I wouldn't have given that story a second glance. But just before Christmas, another series of big shakes rattled Christchurch and I think something has changed.
Until that Friday afternoon the city had not felt a tremor for two and a half months. People were beginning to hope their agony might be over. Sometimes the cruellest blow is not the first or even the worst, it is the one that comes after a respite.
My father and a sister were up from Christchurch for Christmas and I felt their dejection. They have no idea how long this could go on.
At the earthquake inquiry in October, GNS scientist Dr Kelvin Berryman admitted the institute had expected a magnitude six event near or directly under Christchurch after a smaller shake on Boxing Day last year.
He was on a panel of four experts cross-examined by a lawyer representing the interests of families of the 182 people killed by building collapses and falling masonry on February 22.
"Could GNS have calculated the likely ground forces and given people an understanding of what they might expect?" he was asked.
Dr Berryman said they could have provided that information. The GNS team had grappled with the question of whether to make it public, he said.
They decided not to, "because of the range of places where that magnitude six might occur. We didn't want to alarm unnecessarily".
A colleague, Dr Terry Webb, said, "In the first couple of weeks [after the Boxing Day shake] social science advice was that we've got a traumatised population and what you can do to help them cope best ... was to get them coping with aftershocks ... "
So they kept quiet and I dare say wished everyone a happy new year.
I don't blame them too much - what could anyone have done with a warning this time last year? Maybe closer attention would have been paid to one or two buildings weakened by the September quake but, by and large, people would have gone about their lives philosophically.
Nobody had died in the pre-dawn September quake. By Christmas it had become the subject of amusing war stories despite the continuing aftershocks. I can understand the authorities' reluctance to alarm the public at that time.
The significance of Dr Berryman's statement to the inquiry was not the information withheld, it was the fact that information would be withheld. It raises the question, what else might the authorities not want a traumatised population to know?
To cope with trauma, the main thing human beings need to know is, when can we expect it to end? The Government will be asking the same question, as will insurance companies. There must be a great deal of geological science going into it.
All that we know so far is that the magnitude 6.3 "aftershock" of February 22 was followed by one of equal magnitude on June 13 and a magnitude 6.0 on December 23. Hitherto unknown faults under Canterbury are releasing pressure like the cracking of wood fibres in a broken ruler and a year, two years, five years, 50 years, is a nanosecond in geological time.
The good news is that in two big quakes since February 22, the second only eight days ago, nothing much else has fallen down. Plenty of buildings in Christchurch have stood up to phenomenal stresses this year, and new ones can be designed to the same standard.
Likewise, land ruined by subsidence has been identified and it is not so very much. Physically the city can survive, psychologically it's another question.
Everyone asks Cantabrians why they stay? Sometimes Cantabrians ask themselves. The latest jolt, coming after a hopeful lull, will be the last straw for some more. At a certain point a trickle could turn to a torrent. That would be the moment when even people who still wanted to stay decided they needed to get out before their business, job or house value disappeared.
The whole country would suffer as the economy shrank and welfare costs rocketed until the population of its second largest city could be resettled and re-employed elsewhere.
If this is the nightmare behind decisions to suppress geological forecasts, the time has arrived to think again. Human beings can be resilient when they know the worst they might face, but only when they know the worst.
Be fair to them and we can wish them earnestly, a happy new year.By John Roughan Email John