Tuesday, 16 January 2018

Science ship in Lyttelton: Lots of research from NZ's small contribution

A team on a science research vessel are investigating what lies underneath the seabed.
A high-profile and expensive international research ship is heading south via Canterbury to search for new information about climate change.

The Joides Resolution (JR), a former oil industry drilling ship, was in Lyttelton Harbour on Thursday and would depart for Antarctica later this week to drill into ocean sediments in the Ross Sea. The vessel has just spent six weeks drilling into the Hikurangi fault near Gisborne.

New Zealand contributes about US$300,000 (NZ$423,000) annually to the US$150 million International Ocean Discovery Program (IODP), which operates the science aspects of the hip's voyages.

The programme has also drilled into the crater formed when a comet struck the earth near Mexico 65 million years ago.

The contribution earned New Zealand one "seat" on the JR once a year, but because the ship's voyages were clumped geographically, New Zealand got three seats on the ship while it was in the South Pacific.

Two Kiwis led the drilling off Gisborne and a third is heading up the Antarctic drilling programme.
"We're leveraging a massive amount of science out a small contribution," Niwa marine geologist Dr Philip Barnes said.

International interest in New Zealand's undersea geology brought the ship here.

The northern part of the Hikurangi subduction zone was notable because of slow-slip events, he said. While earthquakes were caused by sudden movement along faults, slow slips featured bursts of movement that lasted weeks or months.

They did not cause damaging earthquakes, but their behaviour was not well understood, including what triggered slow slips to become earthquakes.

Slow slip events were discovered only 15 years ago and the Hikurangi fault was notable internationally because the slips there were happening at the shallowest known depth, Barnes said.
The drilling rig on the Joides Resolution could reach them, which was why the 23-country consortium that runs the science programme selected the project for funding, he said.

\While off Gisborne, the ship also probed areas featuring undersea landslides, which could be triggered by earthquakes and cause tsunamis.

Tuesday, 9 January 2018

'A year of two halves': 2017 weather breaks records

2017 was NZ's fifth-warmest year since records began.

Last year was the fifth warmest year on record in New Zealand and one in which swings between extremes toppled longstanding records nationwide.

Niwa's annual climate summary for 2017, released on Monday, shows the year's weather was hard to pin down: it was largely defined by warm temperatures and high rainfall, but ended with record-breaking dry-spells and meteorological drought.

For most of the country, 2017 was warmer and wetter than usual, the report says. All six major cities had clocked up their usual annual rainfall before the end of September and had been on track for record wet years.2017 was a wet year for much of the country.

Many areas broke or nearly broke various high temperature records. No locations broke low annual temperature records.

The year's weather was caused in large part by prevailing high pressure patterns in the east, with northerly winds. The year ended with a marine heatwave and a high pressure system, leading to warm, settled conditions.

Of the major cities, Auckland was the warmest, Dunedin the coldest and driest, Tauranga the wettest and sunniest, and Wellington the most dim.

The average air temperature nationwide was 13.15C, about 0.5C above the long term average. That made it the fifth warmest year since 1909, beaten by 2016, 2013, 1999 and 1998.

While much of the South Island and lower North Island had near normal temperatures, temperatures were above average further north.

The exceptions to the overall trend were in the deep south - Southland and Central Otago were notably drier than usual.

Wednesday, 3 January 2018

New Zealand's ancient penguin was as big as a human

The discovery of New Zealand’s now extinct mega-penguin is attracting world-wide attention.
Fossils of a giant man-sized penguin that once roamed New Zealand sat on a shelf for years before scientists started exploring their secrets.

The bones were found in a chunk of rock on an Otago beach in 2004. The creature measured nearly 1.77 metres long when swimming and weighed in at 101kg.

When standing, the ancient bird was maybe only 1.6m. The biggest penguin today, the emperor in Antarctica, stands less than 1.2m tall.

The newly found bird is about 18cm longer than any other ancient penguin that has left a substantial portion of a skeleton, said Gerald Mayr of the Senckenberg Research Institute and Natural History Museum in Frankfurt, Germany. A potentially bigger rival is known only from a fragment of leg bone, making a size estimate difficult.

Monday, 1 January 2018

Tuesday, 26 December 2017

Warmer oceans: 'We need to start planning for this now'

A report recommends sweeping changes to the recreational fishing sector.
New Zealand's fishing industry could hit a snag if it doesn't plan for warmer oceans significantly affecting marine life, say Niwa scientists.

As the ocean gets warmer it could affect phytoplankton - a key part of the oceans, seas and freshwater basin ecosystems - and could see a reduction in food supply for fish.

"This has already happened in the water just off Tasmania and the south-east corner of Australia, which is warming rapidly as the East Australian current pushes warmer water further south causing huge changes to the ecosystem," said Niwa marine biogeochemist​ Professor Cliff Law.

Tasmania's coastal ecosystems were changing with an increase in subtropical species, which can impact the economy, he said.

"The average warming around New Zealand is 2.5 degrees [Celsius] by the end of this century, which will affect how the ocean mixes and the nutrients available for plankton growth, with knock-on effects on the foodweb and fisheries.

"People tend to think of climate change from a terrestrial angle but obviously, as the ocean is a big part of the globe, there will be significant changes. As it's also a significant part of New Zealand's Exclusive Economic Zone we need to start planning for this now."

Near-record sea surface temperatures described as "off the charts" were reported on Monday.
La Nina pattern and higher than normal atmospheric pressure are warming sea surface temperatures by more than 6 degrees Celsius in some areas, compared to the average for this time of year.


Saturday, 16 December 2017

Yellow-eyed penguins at risk due to set net fishery

Almost half the breeding population of yellow-eyed penguins on Codfish Island, west of Stewart Island, have disappeared at sea, most likely because of commercial set nets, Forest and Bird says.

Forest & Bird chief executive Kevin Hague said the group was calling on the Government to gather those who work to protect the penguins, but also the fishing industry to agree an immediate set of actions to eliminate the risks from set netting in the penguins' feeding area.

"Unlike previous years where disease and high temperatures caused deaths on land, this year birds have disappeared at sea. There is an active set net fishery within the penguins' Whenua Hou foraging ground, and the indications are that nearly half the Whenua Hou hoiho population has been drowned in one or more of these nets.

"We are asking DOC and MPI what they intend to do to save our hoiho from extinction, because at current rates of decline we are on track to lose hoiho completely from mainland New Zealand. We have also written to the Minister of Conservation, expressing our concern."

However, Ministry for Primary Industries (MPI) says it is stepping up monitoring of the set net fisheries.

Almost every penguin killed in the set net fishery was killed on a boat that had an official observer on board, Hague said.

The first step was to get more observers onto set net vessels and prioritise putting cameras on set netting boats, he said.

Department of Conservation information showed only 14 yellow-eyed penguins were found on Codfish Island, down from 24 the previous year.

Forest & Bird said yellow-eyed penguins had also declined elsewhere this year. The Catlins had seen a drop of 10 per cent in nests and Otago Peninsula saw a small decline but not all areas have been searched yet.

The estimate for the entire southern east coast of the South Island was down 6 per cent.
However, it's not just yellow-eyed penguins at risk.

Monday, 4 December 2017

Our scorching sea: Marine heatwave unfolding as hot temperatures continue

The warm weather is predicted to continue for the rest of the week as a ridge of high pressure sits over the country.

The first weekend of summer was marked by scorching temperatures nationwide, and Monday is expected to be even hotter.

Hanmer Springs was the hottest place in the country on Sunday at 31 degrees Celsius, according to MetService.

It's not just air temperatures that have been hot. According to NIWA's Ben Noll, ocean temperatures around New Zealand have been on average 2C warmer than usual - and up to 6C warmer off the West Coast. Water around the country has been warmer than average for more than a month now.

MetService Meteorologist Ciaran Doolin said: "It's good news for the working week. The (high pressure ridge across the country) is set to persist until Friday, which means a continuation of warm, settled weather."