Government science company upgrades its supercomputer

5.00pm - By KENT ATKINSON

Government science company Niwa is upgrading its super-computer -- the nation's biggest and fastest -- to four times its original processing power.

A crane will be used tomorrow morning to hoist into place new components for Niwa's Cray T3E-1200E Massively Parallel Processor supercomputer, which was the fastest in the southern hemisphere when it was installed in June 1999.

At that time, it was rated as the 60th-fastest computer in the world.

Now, even after the installation of add-ons to the computer at the National Institute of Water and Atmospheric Research's Greta Point complex at Wellington, the Cray will be about halfway down the world "top 500" list of computers, even though it will be capable of a massive 500 billion calculations per second.

It will have 544 processors (increased from up from 144), 120 gigabyte main memory (up from 20 gigabytes), and 1200 gigabyte high performance disk storage (up from 600 gigabytes).

Niwa has not disclosed how much it paid Silicon Graphics for the original computer, except that it was cheaper than the $20 million paid in 1999 by the Australian Bureau of Meteorology for a computer doing similar work. This time, the Cray computer company was a partner in the upgrade because of its interest in keeping a supercomputer going at Niwa.

The Cray has been running hugely complex computer "models" of environmental systems, such as climate, fish ecosystems, and atmosphere and ocean circulation.

But Niwa has also been using the Cray to develop computer models for its hazard prediction service, forecasting extreme events such as the occurrence of heavy rainfall and strong winds, together with their impacts on river and sea levels.

It links different computer programmes "modelling" conditions in the atmosphere, ocean, climate and weather and rivers.

High resolution weather predictions coupled to river catchment run-off models will lead to improved forecasts of floods, both in terms of the size of the flood-peaks and when they will occur.

By linking the atmospheric predictions to tidal and storm-surge models, scientists would be able to make the best available prediction for weather, river flows, floods, storm surges and waves for periods of three hours to 48 hours.

Dr Renwick said the Cray was being upgraded because the past five years of work had resulted in the development of a range of complex computer ocean, climate, and weather models.

"The catch now is that even though the machine that we've got has a large capacity, we can't do more than one of those things at once -- and we want to be able to run many of the models," he said.

"We're getting close to a point where we might be able to go 'live' with some of the stuff, so we're going to start doing some quasi-operational testing."

Niwa could now link rainfall and wind data with storm surge and tidal information to predict high and low river flows, and storm damage from winds. The same systems could enable prediction of the dispersal of contaminants such as oil spills, or biological problems such as pests and diseases.

Such a capacity could give the nation's planning agencies the longest possible lead time for accurate hazard warnings. Central government and local councils, as well as civil defence, energy, transport and farming and forestry sectors would be able to use information generated by the computer.

It was becoming increasingly possible to better forecast events such as the February storms and floods which hit the lower half of the North Island.

"The trials we've done to date indicate we should have quite a bit of skill at doing that, over a one to three-day timescale," Dr Renwick said. "Had we been able to run operational forecasts then (in February), we could have been a lot more help".

"We were able to provide information ... we could see this kind of event coming, in broad terms, but we weren't quite in a position to really be as helpful as possible.

"The February floods were pretty extreme, but the sorts of models we've got should be capable of handling that kind of event."

The Cray has been used to develop a prediction system capable of forecasting weather hazards at a local scale, using information from satellites and weather radar.

"I think we'll have something going by the end of this year at the 12km-13km scale," Dr Renwick said. At the same time, work was being done on a new model which could increase the resolution to areas as small as 5km.

The Cray was also being used to look at regional climate variations in global weather patterns, to provide information on climate patterns, and for planners looking at the effects of longer-term climate changes on soil erosion, landslides, forest fires, soil moisture and plankton growth such as the algal blooms which affect marine farming.

Similarly complex research has been carried out in ocean biology, atmosphere composition and transport of greenhouse gases and the marine life and fish stocks.

Dr Renwick said the lift in processing capacity would not only ease the queues of Niwa's own scientists wanting access, but there would be capacity available to be rented out to other science companies.

- NZPA