VSF: I lived in New Zealand for 7 years and still have friends & loved ones there. Thus I am connected to their world and future. I have taken many NASA Worldview screenshots of New Zealand, the Tasman Sea, and Australia. This recent report of the largest wave ever recorded in Southern Ocean reminded me of the many radiation patterns I have seen come from Auckland Island. Here is the report and a few of my images.
Surf’s really up: Largest wave ever recorded in Southern Ocean
By Peter Hannam
10 May 2018
A solitary buoy in the remote Southern Ocean has recorded a monster wave of 23.8 metres, the largest wave ever measured in the southern hemisphere. A wave rider buoy moored at Campbell Island off New Zealand’s South Island registered the huge wave on Tuesday, according to Tom Durrant, a senior oceanographer at Metocean, part of Meteorological Metservice of New Zealand (MetService).
Since the buoy only registered the first 20 minutes of each three hours, “it’s quite possible, even probable, that there were much higher waves during this storm”, Dr Durrant said.
It eclipsed the previous record maximum individual 22.03 metres clocked at an Australian buoy south of Tasmania in 2012. The so-called significant wave height for the event, which is an average of the top third of waves measured from their crest to trough, was registered at 14.9 metres.
That was also a record for the Southern Ocean – but shy of the 19-metre global significant wave height record set in the North Atlantic in 2013, Dr Durrant said.
The generator of the huge waves was a fast-developing low-pressure cell that travelled at the same speed as the waves it was forcing. “Essentially the peak of the waves could stay under the storms for quite a long period of time, and that’s what allowed them to grow so rapidly,” Dr Durrant said.
The waves were roaring up the west coast of New Zealand on Thursday, and will hit North America in about a week’s time, he said.
The storm would have had little impact on southern Australia’s coast – unlike the intense low currently chilling and soaking a region from Victoria and Tasmania, up into NSW.
Snow is expected to settle on elevated regions above 1000 metres, with winds gusting to damaging speeds of 100 km/hour.
The Bureau of Meteorology has issued severe weather warnings for damaging winds and heavy rainfall for the southern half of Victoria and for “vigorous winds” for much of NSW for Friday. Friday maximum temperatures will reach just 11 degrees in Canberra, 15 in Melbourne and 17 in Sydney, with the wind chill making it feel even chillier.
Dangerous and possibly damaging surf is expected to hit the south-eastern Australia coastline from Friday into the weekend.
Southern Ocean research
Australian and New Zealand researchers have been leading efforts to increase knowledge about the ocean to the south of both countries.
“The Southern Ocean is definitely the most under-observed ocean in the world,” Dr Durrant said.
The buoy that measured this event is part of a larger collaborative project with MetService, the New Zealand Defence Force, Defence Technology Agency and Spoondrift. This program includes seven instruments to collect wave data, this moored buoy near Campbell Island and six drifting buoys. It builds on efforts by Australia’s Bureau of Meteorology and CSIRO.
“We are very excited to have these instruments in place and to now be able to measure these extraordinary conditions” he said.
The region accounts for about 22 per cent of the planet’s oceans, and “it’s the most energetic part of the world’s oceans in terms of waves”, he said.
Average wave heights total more than five metres, driven by the strength of winds, the area over which they blow – also called the fetch – and the length time winds are blowing.
Climate change is likely to bring more intense storms, including in the Southern Oceans.
“Assuming climate models are correct about stronger storms, then we can expect bigger waves as well,” Dr Durrant said.
The Auckland Islands (Māori: Motu Maha or Maungahuka) are an archipelago of New Zealand, lying 465 kilometres (290 mi) south of the South Island. It includes Auckland Island, Adams Island, Enderby Island, Disappointment Island, Ewing Island, Rose Island, Dundas Island and Green Island, with a combined area of 625 km2 (240 sq mi). The islands have no permanent human inhabitants.
Ecologically, the Auckland Islands form part of the Antipodes Subantarctic Islands tundra ecoregion. Along with other New Zealand Sub-Antarctic Islands, they were designated a UNESCO World Heritage Site in 1998.
Scientific research and reserve
The 1907 Sub-Antarctic Islands Scientific Expedition spent ten days on the islands conducting a magnetic survey and taking botanical, zoological and geological specimens. From 1941 to 1945 the islands hosted a New Zealand meteorological station as part of a coastwatching programme staffed by scientist volunteers and known for security reasons as the “Cape Expedition”. The staff included Robert Falla, later an eminent New Zealand scientist. Currently the islands have no inhabitants, although scientists visit regularly and the authorities allow limited tourism on Enderby Island and Auckland Island.
New reserves including Auckland Islands were established in 2014, which are about 15 times larger than the reserve on Stewart Island, making Subantarctic islands the largest natural sanctuary in the nation. [Wiki]