Please select your home edition
Edition
Naiad

New Study - Southern Ocean winds strengthen, shrink south

by Sail-World Cruising round-up on 12 May 2014
Southern Ocean winds .. .
If you have ambitions to sail the Southern Ocean and would like to be carried around by the Roaring Forties, you'd better not delay too long. According to some new results from a scientific group the winds are strengthening and moving south.

For the first time, Dr Nerilie Abram, Queen Elizabeth II Research Fellow, Research School of Earth Sciences has led a team which studied data since the year AD1000, and found that Southern Ocean winds are now stronger than at any time in the past 1000 years, and likely to increase.

In the words of Dr Abram to Sail-World Cruising, 'Rising greenhouse gases are causing the westerly winds that circle around Antarctica to get stronger and shift closer to Antarctica. Over the last 50 years the wind belt has shifted south by around 2-5 degrees of latitude, while also getting around 10-15% faster. This is a trend that looks set to continue as greenhouse gas levels continue to rise over the coming century.'

However, the changes will not occur evenly across the year. 'Strengthening of the westerly winds over the coming decades is expected to be most pronounced in the winter months. But during the summer season, a gradual recovery of the Antarctic ozone hole is expected to offset some of the changes being caused by rising greenhouse gases,' she added.

The study has been published in the latest issue of Nature Climate Change.

Antarctica has been warming relatively slowly compared with the rest of the world. The explanation seems to be that the winds spinning clockwise around the continent have been getting stronger, preventing warm air from entering.

In 2009, it seemed that the hole in the ozone layer above Antarctica was responsible for boosting the winds. Dr Abram and her colleagues have shown the ozone hole is only part of the story. Global warming is just as important.

The team reconstructed Antarctic temperatures over the past 1000 years, using an ice core from James Ross Island near the Antarctic Peninsula. The temperatures correlated with how strong and tight the winds are, so they could construct a record of wind strength.

They found that the current strength of the winds is unprecedented over the past millennium. But the surge in strength started in the 1940s, decades before the ozone hole.

So Abram's team simulated the last millennium using eight climate models, driven by actual greenhouse gas levels previously reconstructed from ice cores. All the models predicted that the winds would pick up by the 1940s, suggesting greenhouse gases were playing a role. That may be because the northern hemisphere is warming faster than the south – because it has more continents – creating a strong temperature gradient that boosts the winds.

However, the stronger winds experienced by sailors in the Southern Ocean is one of the milder side effects that scientists are worried about.

'The west Antarctic ice sheet [adjacent to the peninsula] is probably the bit of the Antarctic ice mass that we’ve be most concerned about for the longest time,' Matthew England, from the University of NSW’s Climate Change Research Centre, and a co-author of the paper, said recently.

'If it all melted, that ice sheet could lift global sea levels by 4 to 5 metres, he said.

The full study can be found in the most recent edition of Nature Climate Change
X-Yachts AUS X4 - 660 - 2Abell Point Marina 660x82 MoorMusto 2016 660x82 1

Related Articles

Super Series Sailing Spectacular
News arrived of at least one Australian outfit going for a new build 52. Someone had to entertain Beau Geste and SMB During the week, news arrived of at least one Australian outfit going for a new build 52. Someone had to keep Beau Geste and SMB entertained at the sharp end of the 52 bracket. Two other camps were linked to other former 52 Super Series craft, Phoenix and Spookie, but the one touted as going after Phoenix has denied it, saying that Hasso (SAP) Plattner of Germany has bought her.
Posted on 20 Feb
More marina space and exciting firsts for GC Boat Show and Marine Expo
More marina space and exciting additions to an impressive Fleet of Firsts have set scene for a colossal marine showcase More marina space and even more exciting additions to an already impressive Fleet of Firsts have set the scene for a colossal marine showcase both on water and on land on Queensland’s Gold Coast from 17-19 March.
Posted on 17 Feb
Tenth blog from on board Perie Banou II
The irrepressible, charismatic and yarn-spinning record-breaker known as Jon Sanders is back sailing the oceans The sailor who cannot garden; the irrepressible, charismatic and yarn-spinning record-breaker known as Jon Sanders is back sailing the oceans he knows so well. After his ribs episode on the quay in Cape Town, and making more friends everywhere he goes, Jon is now making for St Helena. So here, in his typical rapid-fire style are his latest exploits...
Posted on 17 Feb
B&G adds enhanced Navionic functionality to Zeus and Vulcan range
B&G® announces the latest updates will bring PredictWind weather services direct to Zeus and Vulcan chartplotter range. B&G®, the world’s leading sailing navigation and instrument specialist, is pleased to announce the latest in its software updates will bring PredictWind weather services direct to its Zeus and Vulcan chartplotter range.
Posted on 16 Feb
Beneteau Open Day at Cruising Yacht Club of Australia
The Beneteau Team will be exhibiting three new Beneteau models at the CYCA this Saturday. The Beneteau Team will be exhibiting three new Beneteau models at the CYCA this Saturday.
Posted on 16 Feb
Lisa Blair enjoys a sunrise crossing of International Date Line
At sea for 20 days, Lisa Blair, 32 reached a key milestone in her attempt to circumnavigate Antarctica solo At sea for 20 days, 13 hours, 4 minutes and 39 seconds, sailor and adventurer Lisa Blair, 32 reached a key milestone in her attempt to circumnavigate Antarctica solo and unassisted crossing the International Dateline at 16:25:39 UTC (05:25:39 local time) on 11 February 2017.
Posted on 11 Feb
Six weeks to go to 2017’s Gold Coast International Boat Show
Come and see over 600 boats for sale on water and on the land as well as engines, accessories and electronics. Come and see over 600 boats for sale on water and on the land as well as engines, accessories and electronics, live entertainment and boating education every 15 minutes across a giant 3km display circuit.
Posted on 10 Feb
On board interview with Lisa Blair - solo Antartica circumnavigation
So far, Lisa is tracking very well in her attempt to become the first woman to sail solo around Antartica. So far, Lisa is tracking very well in her attempt to become the first woman to sail solo around Antartica. After the setbacks of a delayed departure due to gremlins in the electronics, we are delighted to have these answers from her on board. She is well and enjoying her time. Climate Action Now, her Hick 50, left Albany in Western Australia on January 22, 2017.
Posted on 8 Feb
Growing Fleet of Firsts for Queensland’s biggest GC Intl Marine Expo
A very impressive Fleet of Firsts is taking shape even more world-leading marine brands/businesses step aboard this week A very impressive Fleet of Firsts is taking shape as even more world-leading marine brands and businesses step aboard this week with first releases at Australia’s first major boat show of 2017 – the Gold Coast International Boat Show and Marine Expo in March.
Posted on 2 Feb
Yachting cartoonist Mike Peyton dies at 96
“The World’s Greatest Yachting Cartoonist” died on January 25, 2017 just five days after his 96th birthday. Mike Peyton, dubbed “The World’s Greatest Yachting Cartoonist”, died on January 25, 2017 just five days after his 96th birthday. A modest, shy man, he eschewed the spotlight and seemed unaware of the esteem which in sailors all around the world held him.
Posted on 27 Jan