Waiting for the earth to move: Tom Wilkie explains how a small group of British scientists can monitor secret nuclear testing from a north London flat

LAST TUESDAY China exploded a nuclear warhead deep under the desert at its remote Lop Nor nuclear testing site in Xinjiang province, some 2,300km (1,500 miles) west of Peking. The first the outside world knew of this event was when, in the bedroom of a small flat off the Seven Sisters Road in north London, Philip McNab's personal computer woke him up with an ear-splitting siren.

While Mr McNab slept, his computer had been sampling data collected by a network of 71 seismographs and collated at the US Geological Survey's database in Golden, Colorado. The machine recognised the provenance of a 5.5 magnitude 'earthquake', triggered at 2am GMT, and alerted Mr McNab. It was spectacular confirmation of a prediction made two weeks earlier by Vertic, the Verification Technology Information Centre, for which Mr McNab works. On 22 September, Vertic's analysts had declared that a Chinese nuclear test was imminent.

Contrary to popular belief, commercially available satellite images are too coarse to pick out fine details - such as trucks or even large buildings. It took years of developing computer programs to squeeze the maximum information out of these images before Vipin Gupta, a research student at Imperial College, was able to produce the first detailed maps publicly available in the West of the Lop Nor testing site. Mr Gupta, who has devoted the three years of his PhD research to the site, knows it so well that he was able to pick out the preparations for a nuclear test and his analysis was so reliable that Vertic was able to make the advance warning public.

Last Tuesday China initially refused to confirm that it had conducted a nuclear test, confusing the matter by referring to natural seismic activity in the region. But when, on Vertic's behalf, Dr Roger Clark, a geophysicist at the University of Leeds, analysed records from seismographs at Harrogate, Durham, Richmond, Whitby, Huddersfield and Market Rasen, the traces were clearly characteristic of a nuclear explosion rather than a natural earthquake. It had taken just 9 1/2 minutes for the seismic waves from the explosion, estimated at between 20 and 40 kilotons, to arrive in the UK.

Vertic is a small group of independent scientists and engineers who have no access to the classified intelligence reports or high-quality surveillance satellite images available to governments. This was by no means the first time, although perhaps the most spectacular, that its expertise has been demonstrated. But the news that its prediction had come true was received with mixed feelings at Vertic.

The Chinese explosion may have destroyed the momentum that had been growing among the nuclear weapons states to reach agreement on a treaty banning all nuclear weapons tests. A Comprehensive Test Ban (CTB) treaty has been a long-term aim of international diplomacy since the Partial Test Ban, which outlawed test explosions in the air, outer space or underwater but which permits underground tests, came into force in 1963.

Negotiations to achieve a CTB open in Geneva in January next year. A comprehensive test ban is seen as an essential part of a wider strategy to prevent the spread of nuclear weapons to more nations. The issue is pressing, because the Treaty on the Non-Proliferation of Nuclear Weapons comes up for renewal in 1995, and non-nuclear states have been pressing for a CTB as evidence of good faith on the part of the superpowers.

One of the stumbling blocks on the road to a comprehensive nuclear test ban has been worry about the possibility of some nations cheating and going undetected. If the discussions at the Conference on Disarmament in Geneva do bear fruit in the shape of a comprehensive ban, then it will be due in no small measure to the efforts of Vertic in reassuring the negotiators that detection is possible.

The sheer quality of Vertic's technical work goes some way to explaining how this tiny organisation has become a force to be reckoned with, consulted by governments. But it combines with technical expertise a commodity not usually associated with scientists and engineers: political sensitivity and an understanding of diplomacy. In no small measure, the success of the organisation rests with its director, Patricia Lewis.

Dr Lewis is unusual in a number of respects. Female physicists are comparatively rare; still rarer are those with a PhD in nuclear structure physics. After a year off in India, she spent several years lecturing in physics at Auckland and Canberra universities, studying high-spin states of atomic nuclei, calcium-42 in particular. However, as she now puts it, 'I had fallen out of love with physics.' At the end of her three-year appointment, 'I didn't want to carry on. I wanted to do science journalism.'

She had her first brush with the military side of the atom through the agency of Sana - Scientists Against Nuclear Arms - when nuclear weapons in the South Pacific were big issues in New Zealand. She returned to the UK just at the time that Jeremy Leggett, a young geologist at the Royal School of Mines, realised that his science was being abused by the military establishments of the nuclear weapons powers.

Dr Leggett knew that anyone who tried to explode a nuclear weapon underground could be detected. Both the scientific understanding and the seismic technology existed. The problem was that the military had a monopoly of the science, its interpretation, and of the channels by which information was communicated to government.

Vertic was set up to break this monopoly. At first, Dr Leggett combined his work at Imperial College with Vertic. Dr Lewis became its first employee and then became director in 1989, when Dr Leggett was made Greenpeace's first director of science.

Vertic's analysis of Chinese nuclear testing is perhaps the most vivid illustration of what its scientists can do, even when they are confined to using publicly available data. The organisation's remit stretches much wider than nuclear weapons. It has been involved in verification measures for conventional force reductions in Europe, and in extending verification to cover environmental issues, such as how one might monitor the production of greenhouse gases. 'We are expanding into biodiversity, endangered species and desertification,' Dr Lewis says.

Much of her time is occupied with finding funds, mainly from charities, for Vertic. 'We never take money from governments for the baseline - salaries and rent,' she explains. Vertic does accept commissions for specific projects, but these are additional. 'We never have to need the money, so they have no hold over us.'

The most immediate item on Vertic's agenda is to update its study on verifying a comprehensive nuclear test ban, in time to be of use to the Conference on Disarmament when it revisits the topic next January. But Dr Lewis believes verification can build confidence between states on a regional as well as global scale. She would like to start a project that would bring military experts from India and Pakistan to Europe to look at the verification of troop reductions and to attend on-site inspections. In this way it might be possible for the two countries on the Indian sub-continent to reach their own agreements, so rebuilding confidence between them.

It is a far cry from the nuclear structure of calcium, but perhaps no further than from the deserts of Xinjiang to the Seven Sisters Road.

(Photograph omitted)

people'It can last and it's terrifying'
Danny Welbeck's Manchester United future is in doubt
footballGunners confirm signing from Manchester United
footballStriker has moved on loan for the remainder of the season
footballFeaturing Bart Simpson
Katie Hopkins appearing on 'This Morning' after she purposefully put on 4 stone.
peopleKatie Hopkins breaks down in tears over weight gain challenge
Arts and Entertainment
Olivia Colman topped the list of the 30 most influential females in broadcasting
Kelly Brook
peopleA spokesperson said the support group was 'extremely disappointed'
The five geckos were launched into space to find out about the effects of weightlessness on the creatures’ sex lives
Life and Style
techIf those brochure kitchens look a little too perfect to be true, well, that’s probably because they are
Andy Murray celebrates a shot while playing Jo-Wilfried Tsonga
TennisWin sets up blockbuster US Open quarter-final against Djokovic
Arts and Entertainment
Hare’s a riddle: Kit Williams with the treasure linked to Masquerade
booksRiddling trilogy could net you $3m
Arts and Entertainment
Alex Kapranos of Franz Ferdinand performs live
music Pro-independence show to take place four days before vote
ebooksAn unforgettable anthology of contemporary reportage
news Video - hailed as 'most original' since Benedict Cumberbatch's
Life and Style
The longer David Sedaris had his Fitbit, the further afield his walks took him through the West Sussex countryside
lifeDavid Sedaris: What I learnt from my fitness tracker about the world
Arts and Entertainment
Word master: Self holds up a copy of his novel ‘Umbrella’
booksUnlike 'talented mediocrity' George Orwell, you must approach this writer dictionary in hand
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Maths Teacher

£120 - £162 per day: Randstad Education Hull: Randstad Education are currently...

SQL Implementation Consultant (VB,C#, SQL, Java, Eclipse, integ

£40000 - £50000 per annum + benefits+bonus+package: Harrington Starr: SQL Impl...

SQL Technical Implementation Consultant (Java, BA, Oracle, VBA)

£45000 - £55000 per annum + Benefits + Bonus: Harrington Starr: SQL Technical ...

Head of IT (Windows, Server, VMware, SAN, Fidessa, Equities)

£85000 per annum: Harrington Starr: Head of IT (Windows, Server, VMware, SAN, ...

Day In a Page

'I’ll tell you what I would not serve - lamb and potatoes': US ambassador hits out at stodgy British food served at diplomatic dinners

'I’ll tell you what I would not serve - lamb and potatoes'

US ambassador hits out at stodgy British food
Radio Times female powerlist: A 'revolution' in TV gender roles

A 'revolution' in TV gender roles

Inside the Radio Times female powerlist
Endgame: James Frey's literary treasure hunt

James Frey's literary treasure hunt

Riddling trilogy could net you $3m
Fitbit: Because the tingle feels so good

Fitbit: Because the tingle feels so good

What David Sedaris learnt about the world from his fitness tracker
Saudis risk new Muslim division with proposal to move Mohamed’s tomb

Saudis risk new Muslim division with proposal to move Mohamed’s tomb

Second-holiest site in Islam attracts millions of pilgrims each year
Alexander Fury: The designer names to look for at fashion week this season

The big names to look for this fashion week

This week, designers begin to show their spring 2015 collections in New York
Will Self: 'I like Orwell's writing as much as the next talented mediocrity'

'I like Orwell's writing as much as the next talented mediocrity'

Will Self takes aim at Orwell's rules for writing plain English
Meet Afghanistan's middle-class paint-ballers

Meet Afghanistan's middle-class paint-ballers

Toy guns proving a popular diversion in a country flooded with the real thing
Al Pacino wows Venice

Al Pacino wows Venice

Ham among the brilliance as actor premieres two films at festival
Neil Lawson Baker interview: ‘I’ve gained so much from art. It’s only right to give something back’.

Neil Lawson Baker interview

‘I’ve gained so much from art. It’s only right to give something back’.
The other Mugabe who is lining up for the Zimbabwean presidency

The other Mugabe who is lining up for the Zimbabwean presidency

Wife of President Robert Mugabe appears to have her sights set on succeeding her husband
The model of a gadget launch: Cultivate an atmosphere of mystery and excitement to sell stuff people didn't realise they needed

The model for a gadget launch

Cultivate an atmosphere of mystery and excitement to sell stuff people didn't realise they needed
Alice Roberts: She's done pretty well, for a boffin without a beard

She's done pretty well, for a boffin without a beard

Alice Roberts talks about her new book on evolution - and why her early TV work drew flak from (mostly male) colleagues
Get well soon, Joan Rivers - an inspiration, whether she likes it or not

Get well soon, Joan Rivers

She is awful. But she's also wonderful, not in spite of but because of the fact she's forever saying appalling things, argues Ellen E Jones
Doctor Who Into the Dalek review: A classic sci-fi adventure with all the spectacle of a blockbuster

A fresh take on an old foe

Doctor Who Into the Dalek more than compensated for last week's nonsensical offering