When it comes to earthquakes, the December–February quarter was a little quieter in 2002/03 than it was in the previous year, according to a report released today by the Natural Hazards Centre. There were 91 earthquakes of magnitude four and above, compared with 119 in the same period in 2001/2002.
Christchurch has a severe air pollution problem, especially during winter. This winter, scientists from NIWA will be using a $150,000 spectrometer to examine how this local air pollution reduces the amount of UV radiation that reaches the earth’s surface.
With the increasing focus on renewable energy sources, how can we find the best places to put new wind farms? NIWA scientists are using several new tools, including one which uses sound waves, to help answer this question.
If we want to get the best generating capacity out of wind turbines, we should put them in places with the highest average speeds. The wind in a particular place consists of a few storms, some calm periods, and everything else in between. If we put all these conditions together, we get the average wind speed.
During the first week of March NIWA will be conducting experimental work to assess survivorship amongst snapper tagged with its newly developed electronic tag. Snapper will be caught using commercial trawl and long-line vessels from waters close to Kawau Island. The snapper will then be tagged, placed into a large sea cage and monitored for two weeks.
When it comes to earthquakes, spring was much quieter in 2002 than it was in 2001. There were only 89 earthquakes of magnitude four and above in spring 2002, compared with 291 in the same period in 2001.
For some South Pacific countries east of the date line the chances of tropical cyclone activity are higher than normal for the November 2002–January 2003 period, according to NIWA climate scientist Dr Jim Salinger.
“Pacific Island countries with increased risk over this period are Wallis and Futuna, Samoa, Tokelau, Niue and the southern Cook Islands” he said. “Tropical cyclones are still very likely about and west of the date line, but a lower than normal frequency of occurrence is expected.”
New Zealand is in a tectonically active part of the roaring forties and is vulnerable to a wide range of natural hazards. Yet, the threats of a tsunami in New Zealand are underrated, according to the latest report from the Natural Hazards Centre.
How much warning of an impending flood can we give a community? Scientists at the National Centre for Water Resources can now give flood forecasts for some areas of the country up to 48 hours ahead. A pilot project is underway in 12 catchments around New Zealand, with the eventual aim of covering the whole country.
Very high August temperatures occurred yesterday, as warm northwesterlies fanned the east coast of the South Island. This pushed the mercury up to 24.8°C at Waipara in North Canterbury, almost a new New Zealand record for the month of August.
Other high temperatures yesterday were:
2nd highest for August since records began in 1954 (22.8°C in 1970)
New Zealand’s marine and freshwater environments are extremely important for our economic and social welfare, but they are under constant pressure from human uses and introductions of new invasive species.
There are more than 150 exotic marine species in New Zealand’s coastal waters already, and at least one new species arrives every year according to a report in NIWA’s new Aquatic Biodiversity & Biosecurity newsletter, published today.