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'Record-breaking' wild weather for South Island

By MICHAEL FORBES - The Press | Monday, 01 September 2008

A record high-pressure system is expected to drop more rain on parts of the South Island, over the next three days, than Hurricane Gustav will on New Orleans, according to the MetService.

In a weather warning issued at 8:59am this morning, the MetService is predicting a weather front to stall over Fiordland and South Westland which could bring in excess of 500mm of rain to the Westland Ranges and Southern Alps.

That would exceed the 200mm Hurricane Gustav is expected to dump on parts on the United States when it hits, according to MetService Weather ambassador Bob McDavitt.

"The difference is, Fiordland is used to this much rain but New Orleans ain't," he said.

The wild weather is the result of a record-breaking, 1040HP high-pressure system, which McDavitt said is a first for New Zealand

"It's breaking all records, we've never seen a high this big over the country before.

"We haven't got any explanation as to why this high-pressure is so high."

Strong winds are also expected to batter the South Island, with gusts up to 140kmh predicted for inland and exposed parts of Southland, Otago, and Canterbury this afternoon, easing later tonight.

McDavitt said the winds would be strong enough to remove insecure objects and cause damage to tress and power lines.

The rain is expected to become heavy for Fiordland after about midday today, with 100 to 120mm predicted to fall in the next 24 hours.

The same amount of rain is also expected to fall in the headwaters of Otago and Canterbury from 6pm tonight until midnight Tuesday.

Lakes look to weather bomb for big boost

Tuesday September 02, 2008 By Jarrod Booker, NZ Herald

Lake Pukaki North of Twizel is one of the major Hydro lakes.

Records are under threat in a clash of weather systems expected to provide a desperately needed boost to dwindling hydro lakes.

A high pressure system to rival the most intense ever recorded in New Zealand is hovering over the South Island, blocking an active front that may drop about 500mm of rain before easing tomorrow - more than twice the rainfall expected from Hurricane Gustav in parts of the United States.

With the southern hydro lakes so low in the south that some may be lowered below minimum operating levels, the rain was coming at a crucial time.

MetService severe weather forecaster Erick Brenstrum said the hydro lakes would benefit from the heavy rain spilling over "without a shadow of a doubt".

"It's just a question of how much. I think it is going to be significant."

Hydrologist Dave Stewart said the rain was "extremely timely" with North Island electricity production working "flat out" to send power south. "A large boost will take a hell of a lot of pressure off."

Mr Brenstrum said the high pressure system over the south was expected to have a central pressure of 1049 hectopascals "which is extremely high for this part of the world".

The centre of this system was over the sea, but the highest pressure over land recorded in New Zealand was 1046hp, in the late 1800s. (Abridged)

Christchurch flights delayed by fog

The Press | Wednesday, 10 September 2008

Daniel Tobin

Take-off: A Jetstar flight leaves Christchurch International Airport today. It was one of the few flights that managed to get out as fog disrupted operations.

Thousands of passengers face delays after fog caused disruption at Christchurch International Airport this morning.  At least 25 domestic and international flights were cancelled, delayed or diverted as thick fog made flying conditions at the airport dangerous.

The fog lifted at about 11am and the airlines are working to clear backlogs.

Climate blamed for glaciers' melt

Sep 14, 2008  TVNZ

Global warming is being blamed for New Zealand's disappearing southern glaciers.

National Institute of Water & Atmospheric Research (NIWA) scientists have recorded the lowest ice volume for the Southern Alps since records began 32 years ago.

They say the 50 glaciers surveyed have suffered an ice loss more than twice the size of Auckland's Rangitoto Island.

"It means that we're losing our snow and ice resource and of course this is important for tourism and it's also important for water resources that flow into the Southern Lakes," says NIWA Principal Scientist Dr Jim Salinger.

Using a small fixed wing aircraft, NIWA has been recording the height of the snow line at the end of each summer.

Salinger says between April 2007 to March 2008, the Southern Alps glaciers lost 2.2 billion tonnes of permanent ice, the fourth largest annual loss since the study began.

He says the glaciers are showing the lowest ice mass on record.

Salinger blames La Nina conditions over New Zealand, more easterlies and warmer than normal temperatures for the rapid shrink rate of the glaciers. They meant less snowfall in the Southern Alps, and more snowmelt.

Worldwide, glaciers are melting at a rate of half a metre a year.

Heavy snow likely to bolster southern glaciers

Paul Gorman Science reporter - The Press | Monday, 15 September 2008

Alan Wood

RETREATING: Heavy alpine snowfalls in the South Island this winter could temporarily halt or even reverse the continuing decline of glaciers in the Southern Alps.

Heavy alpine snowfalls in the South Island this winter could temporarily halt or even reverse the continuing decline of glaciers in the Southern Alps.

The latest survey by the National Institute of Water and Atmospheric Research (Niwa) draws the gloomy conclusion that the country's glaciers are shrinking at an alarming rate.

The total ice volume of the Southern Alps' glaciers is 44.9 cubic km, the least since the annual survey began 32 years ago. However, the stormy winter means the snowpack in some parts of the Southern Alps is the greatest it has been for about a decade.

Power company Meridian Energy is eagerly awaiting a large spring thaw and the boost it will give to its southern hydro-lakes, which are only just starting to recover from very low levels throughout the winter.  Niwa principal climate scientist Jim Salinger said that extra snow could boost the ice mass quite quickly in some smaller glaciers but would not show up in larger glaciers for years.

"It depends what happens over the summer. We've still got the snow melt to come that's November to February and maybe March. If it's a cold summer, it might halt the decline a little, but the general trend is downward." (Abridged)

Hole in the ozone layer widens in 2008

by Rich Bowden - Sep 18 2008, 23:29  TECH HERALD

Ozone hole in Sept. 2006. Credit: NASA

The hole in the ozone layer over Antarctica will be wider in 2008 than reported in 2007, a new U.N. study has said.

The U.N.'s World Meteorological Organisation (WMO) has advised that the observed changes in the stratospheric measurements will delay the repair of the ozone hole and called on its member states to continue to support observations and prevent further damage.

Speaking at the International Day for the Preservation of the Ozone Layer on September 16, U.N. Secretary-General Ban Ki-moon said it would take many years before the ozone layer fully recovers from damage caused by chemicals such as chlorofluorocarbons (CFCs).

“After decades of chemical attack, it may take another 50 years or so for the ozone layer to recover fully. As the Montreal Protocol has taught us, when we degrade our environment too far, nursing it back to health tends to be a long journey, not a quick fix,” he said.

The 1987 Montreal Protocol was signed amongst member nations to phase out substances harmful to the ozone layer. Among these were CFCs and HCFCs (hydrochloroflourocarbons).

According to the most recent measurements taken by the WMO, the ozone hole, though appearing later in the year than usual, will exceed the size reached in 2007 as it reaches its peak towards the end of September and early October.

Using ground observations, measurements from balloons and satellites, and accompanying meteorological information, WMO scientists found that the hole covered an area of 27 million square kilometres on September 13 of this year. The maximum area reached in 2007 was 25 million square kilometres.

The scientists say they are aware of the effect climate change is having on the ozone hole. According to a statement released by the WMO, an excess of greenhouse gases, while causing a warming effect in the troposphere and on the Earth's surface, results in a cooling effect in the stratosphere, accelerating the ozone damage.

"Increased atmospheric concentrations of greenhouse gases (GHGs) will lead to warmer temperatures in the troposphere and at the Earth’s surface," the statement said.

"In the stratosphere, at altitudes where we find the ozone layer, there will be a cooling effect. A cooling of the stratosphere in winter over the last decades has indeed been observed, both in the Arctic and in the Antarctic. Lower temperatures enhance the chemical reactions that destroy ozone," it added. 

"At the same time, the amount of water vapour in the stratosphere has been increasing at the rate of about one per cent per year. A wetter and colder stratosphere means more polar stratospheric clouds, which is likely to lead to more severe ozone loss in both polar regions."

Antarctica to have biggest ozone hole in ``one or two weeks''

SIFY News Wednesday, 17 September, 2008, 11:55

Toronto: A new Canadian study says that cosmic rays, not chlorofluorocarbons (CFCs), are the main cause of the depletion of the ozone layer in the earth's atmosphere. The study also predicts that the largest ozone hole - larger than the size of the US and Canada combined - will occur over Antarctica in ``one or two weeks.''

The ozone layer in the earth's atmosphere absorbs the sun's high-frequency ultraviolet rays which are deadly for life on earth and cause diseases such as skin cancer and cataracts.

Qing-Bin Lu, a professor of physics and astronomy at the University of Waterloo and a specialist in the study of ozone depletion, said on Tuesday that his study belies the two-decade-old theory that the earth's ozone layer is depleted by chlorine atoms produced by sunlight-induced destruction of chlorofluorocarbons (CFCs) in the atmosphere.

On the contrary, he said, more and more evidence points to a new theory that the cosmic rays - energy particles that originate in space - play a major role in the destruction of the ozone layer. Lu said data from several sources, including satellites of the National Aeronautics and Space Administration (NASA), confirmed a strong link between cosmic ray intensity and ozone depletion.

He said laboratory measurements also demonstrated a mechanism by which cosmic rays cause drastic reactions of ozone-depleting chlorine inside clouds over the South Pole (Antarctica).

Satellite data from 1980 to 2007, covering two full 11-year solar cycles, also demonstrated a significant link between cosmic rays and ozone depletion, he said.

``This finding, combined with laboratory measurements, provides strong evidence of the role of cosmic-ray driven reactions in causing the ozone hole and resolves the mystery why a large discrepancy between the sunlight-related photochemical model and the observed ozone depletion exists,'' said Lu.

Recent experiments by the World Meteorological Organization and the United Nations Environment Programme, which use photochemical models, predict the earth's ozone hole will increase by one to 2.5 per cent and the Antarctic springtime ozone hole by five to 10 per cent between 2000 and 2020.

In sharp contrast, Lu said, his study predicted the severest ozone loss — resulting in the largest ozone hole — over the South Pole (Antarctica) this month.  He also predicted another large ozone hole around 2019.

Maaaaarvelous weather for lambs

By Neal Wallace on Fri, 19 Sep 2008   Otago Daily Times

Telford Rural Polytechnic student Nathan Wedd (left) and farm technician Charles Millward show off some of the lambs at Telford this week.

A wet, cold end to winter caused some grief for dairy farmers, but several weeks of settled, warm weather has coincided with lambing, with farmers reporting a relatively easy and enjoyable start to spring.  There are reports of high lamb survival rates, despite scans revealing varied pregnancy rates after a tough summer and autumn.  (Abridged)

Turoa snow base reaches 5m milestone

Friday, 19 September 2008 STUFF NEWS-NZPA

Another 24 hours of snow falling on the southern slopes of Mt Ruapehu has seen Turoa's snow base reach a record five metres today.

In mid-August, the snow measuring stake at Turoa had to be extended from its previous maximum of 3.8m to allowed continued measurement as the snow kept coming.

The skifield set a record for any ski area in New Zealand when its snow base reached 4.5m.

With the snow stake measuring 4.88m on Monday, Ruapehu Alpine Lifts announced that Turoa would extend its season until November 16.

The Whakapapa side of the mountain currently has a base of 3.77m, the deepest since 1995.

Mt Ruapehu marketing manager Mike Smith said the continuous snowfalls from mid-July to late August had created the record conditions.  (Abridged)

Weather with a jazz beat

Sep 21, 2008  Herald on Sunday  Anna Leask and Anna Rushworth

Forecaster Bob McDavitt

Kiwis can expect a little bit of everything when it comes to the weather this summer. Conditions are usually determined by the dominant weather in spring, but MetService weather ambassador Bob McDavitt said the pattern until November would be neutral, between El Nino and La Nina.

"There will be more variety. Not one weather system - hot or cold - will dominate. They will share it," McDavitt said.

"El Nino and La Nina will take turns taking over the main weather theme. All the weather patterns will dominate - but they are not going to fight over it."

McDavitt compared weather patterns to an orchestra.

When El Nino is the composer, we get "marching music", La Nina is more "more romantic", and a neutral pattern is like jazz - everyone gets a turn being the boss.

During an El Nino pattern New Zealand tends to experience stronger or more frequent winds from the west in summer, typically leading to drought in east coast areas and more rain in the west.  A La Nina summer was usually characterised by more northeasterly winds, which tend to bring rainy conditions to the northeast of the North Island, and reduced rainfall to the south and southwest of the South Island.

"Each pattern will hang on for a week or two, so we'll get hot then cold, wet then dry," said McDavitt. "We'll get a variety of weather but it won't be erratic."

National Institute of Water and Atmospheric Research senior climate scientist Dr Jim Salinger said the official summer seasonal forecast would be released in November.

"It's too early to predict what that forecast will be but it might be a bit warmer than normal," he said.

Weather Watch analyst Philip Duncan said neutral periods could be hard to forecast and spring was not an indication of what we would get in summer. He said there were further difficulties with predictions because of the range of "micro climates" in New Zealand and its size.

"We are two small islands stuck bang in the middle of the southwest Pacific."

Duncan said that in the short term, the neutral spring would bring more westerly winds, meaning warmer weather for the east coast but cooler spells in the west of the country.

But if the neutral system continued into summer Duncan predicted Auckland, Bay of Plenty and Hamilton would have a wetter, but warmer, summer than the last.

Humidity levels would be high, increasing the chance of more showers.

In Northland there was always the chance of a tropical cyclone brushing the region in cyclone season between November and April, he said.

One weather analyst preferred to use the cycles of the moon rather than satellites for long-range weather predictions. Ken Ring has been using the technique for 35 years and said it gave him an edge over mainstream weather experts.

"We have alternative medicine and alternative music, I like to think this is just alternative weather."

He is predicting a sudden rise in temperature around mid-November before rain in the month's last 10 days.

Ring also predicted heavy rain in the first week of December but mid-December to February would be mainly dry for Northland, Auckland, Canterbury, Hawke's Bay and the Bay of Plenty.

For Christmas Day Ring predicts the best weather in the top half of the North Island and east of the South Island, but says it will be cloudy through inland Otago and Southland.

The hottest places may be Gisborne and Hawke's Bay in the North Island and Canterbury and South Canterbury in the South Island.

Wellington was Ring's pick for the best New Year weather, while Christchurch would be cloudy and Auckland could have rough weather in the Hauraki Gulf.

Weather depresses lamb count

By DIANE BISHOP - The Southland Times | Tuesday, 23 September 2008

ID 130290/DIANE BISHOP

Three's company: A triplet and her lambs.

Southland plains farmers are not expecting to break any lambing records this season.

Those spoken to by The Southland Times reported an average to below-average lambing at the halfway point — the varying results because of different peak lambing dates.

Riverton farmer Leon Black said his lamb deaths had been high, with both newborn and several-day-old lambs succumbing to the ongoing wet conditions. Since heavy rain fell in early September there had been very little drying and many paddocks remained waterlogged.

Central Southland Vets veterinarian Andrew Roe said lamb deaths had been higher than usual because of the wet weather. "A lot of farmers who lamb in early September were caught out by the heavy rain," he said. Federated Farmers Southland meat and fibre chairman Martin Hall, who farms on the coast at Kapuka, and has just started lambing, said plenty of sunshine was needed to improve grass growth.  (Abridged)

Winds thrash the south but little damage

By KYLIE WILSON and BRUCE FRASER - The Southland Times | Wednesday, 24 September 2008

ID 130912/TRACEY McKENZIE

BOUNCING BACK: Strong winds yesterday took off with Tracey McKenzie's family trampoline and left it hanging in the trees at Mimihau in Eastern Southland.

Wild weather continued to batter the southern region yesterday as strong north-west winds swept through Southland but little damage was reported.

The MetService issued a severe weather warning yesterday for inland Southland and Stewart Island as winds were expected to reach 70kmh, with gusts up to 130kmh.  Strong winds had the potential to damage trees and power lines, and could make driving hazardous, particularly for motorcycles and high-sided trucks, it said.  (Abridged)

Sightseers run for lives as side of mountain falls

By MIKE HOULAHAN - The Press | Friday, 26 September 2008

NEW SCAR: An aerial photo looking along the highway towards Milford Sound, where an old slip on Mount Underwood is shown on the left and the new slip on the right.

Wet weather gear and gumboots are not designed for speed but two Milford Sound women ran like Olympic sprinters when they heard several hundred tonnes of mud, rock and foliage roaring towards them.

Iben Hall and Maria Kuster were sightseeing with five other locals on Tuesday afternoon when the group stopped to admire Mount Underwood, site of a big landslide in 1993.

Hall and Kuster lingered to admire the view while their friends drove further down the road.

Soon after they set off to walk after the group a crash warned the women another slide was on its way and it was about to sweep them away with it.

"We were nearly under it," said Kuster, who works at the Milford Sound Observatory.

"There was this massive rumble, and we saw trees heading towards us ... if we hadn't started running we would have been 20m into it. It was quite scary and absolutely amazing to see that close.

"To actually see rock peel off and comprehend what does it is quite amazing. Especially when you think that just a second longer here taking wet weather gear off, or admiring a waterfall, has saved your life.

"I definitely didn't (know I could run that fast), especially in over-sized gumboots.

A kilometre down the road, Hall and Kuster's friends heard the slip and feared the worst.

Carter and four others were trapped in their van on the other side of the slip by the torrent of water slewing across the road.

At the lodge yesterday, Kuster said there had been 90mm of heavy rain in two hours on Tuesday afternoon, which had flushed a lot of the fallen trees and other debris away.

New Zealand Transport Agency spokesman Murray Clarke said the slip had carpeted 200m of the Te Anau-Milford highway. It would take until Sunday, weather permitting, to clear one lane of the road. (Abridged)

South pacific faces 8 to 10 storms this season

By MICHAEL FIELD - Fairfax Media | Friday, 26 September 2008

Climatic conditions this summer give New Zealand an increased risk of being hit by a tropical cyclone, NIWA says in a forecast.

"There is just over a four out of five chance of an ex-tropical cyclone passing within 500 kilometres of the country sometime between November and May, with the highest risk districts being Northland and Gisborne," NIWA says.

"By the time such systems reach New Zealand they are no longer classified as tropical cyclones, but can still cause strong winds and heavy rainfall."

The most common months for ex-tropical cyclones to affect New Zealand are January to March.

New Zealand is at an increased risk because of the neutral El Nino/Southern Oscillation (ENSO) conditions.

Across the Pacific the coming tropical cyclone season, from November 2008 - May 2009, will see a normal risk of cyclones.

There is a reduced risk in parts of French Polynesia.

"There is a good chance that the first tropical cyclone of the coming season in the South Pacific region may occur before the end of December, which is normal during neutral seasons."

They expect on average eight to ten cyclones over the entire South Pacific region during a neutral ENSO season.

Peak cyclone occurrence is usually from January to March.

In seasons with similar climate backgrounds, several tropical cyclones usually occur in the region between Vanuatu, New Caledonia, Fiji, and Tonga, while a few affect other areas.

In an average season about half of the tropical cyclones that develop reach hurricane force with mean wind speeds of at least 64 knots (118 km/h).

Blossom festival draws thousands

By Rosie Manins on Sat, 27 Sep 2008  Otago Daily Times

Bad weather delayed Alexandra's annual Blossom Festival float parade by an hour today, although thousands of people still managed to brave cold, windy, and wet conditions to watch the procession.

More snow is on the way

Mon, 29 Sep 2008 Otago Daily Times

Sheep straggle through snow-covered paddocks on the Crown Range above Arrowtown on Saturday. Photo by Matthew Haggart.

Residents in the Queenstown Lakes district and Central Otago may want to think twice before packing away their winter woollies, after a snowfall over much of the region on Saturday and with more forecast for tonight.

A MetService weather forecaster said snow fell to about 300m on Saturday morning.

Arrowtown recorded 10cm in places and Jollys Pass, about 20km north of Lumsden on State Highway 6, recorded 15cm.  The MetService said 13cm was recorded at St Bathans and 10cm at Naseby.  (Abridged)

Morning whiteout: frost sends growers scrambling

29.09.2008  JOE DAWSON   Hawke’s Bay Today

The frigid temperatures did not put off these hardy souls training at Hawke's Bay race course.

Vineyard managers will have an anxious wait today until the damage of a heavy overnight frost can be accurately gauged.  Frost-fighting helicopters, wind turbines and sprinklers were in full effect until 8am in places, desperately trying to stir up air that had dropped to below zero degrees.  (Abridged)

Daylight Saving Brings Skin Cancer Warning

29 September, 2008   NZ Herald

New Zealanders are being warned of rapid increases in ultraviolet radiation as people enjoy the longer days of daylight saving.

Dr Richard McKenzie of the National Institute of Water and Atmospheric Research (NIWA) says the switch to daylight saving should remind us that this is a transition period for New Zealand, when the sun is higher in the sky each day.

“It means the sun’s rays have less distance to travel through the atmosphere to reach earth. The shorter the distance the rays have to travel, the less ultraviolet radiation is absorbed by gases in the atmosphere – like ozone – and the more radiation hits earth.”

He says over the last week alone, we have seen ultraviolet radiation rise from six to seven in the north of the country.  With UV rays peaking at over 12 in the summer, people are being urged to protect themselves from the harmful effects of the sun, while still enjoying the outdoors.

Dr McKenzie says that because the sun elevation angle is a strong indicator of UV intensity, an easy way of judging how high the UV radiation is likely to be is by observing the length of your shadow.

“As your shadow gets shorter, you know the UV risk is getting bigger. If your shadow is less than twice the length of your body, there is a risk of damage from UV. At this time of year, your shadow length at midday is about the same length as your body and it will get shorter each day as summer approaches.”

He says the key time for New Zealand is over the December-January period when the sun is high in the sky so the ultraviolet intensity reaches its maximum values. At that time of the year, New Zealand can also be influenced by the break up of the ozone hole in Antarctica.

The precise date of break-up of the Antarctic ozone hole is not yet predictable. But it is usually in the early summer. NIWA provides daily forecasts of UVI to the media via MetService. Forecasts are also available at http://www.niwa.co.nz/services/free/uvozone.  (Abridged)

ENDS