Why The Sea Temperatures Downunder Were The Hottest On Record

The summer of 2015-2016 was one of the hottest on record in Australia. But it has also been hot in the waters surrounding the nation: the hottest summer on record, in fact.

Difference in summer sea surface temperatures for the Australian region relative to the average period 1961-1990. Australian Bureau of MeteorologyDifference in summer sea surface temperatures for the Australian region relative to the average period 1961-1990. Australian Bureau of MeteorologyWhile summer on land has been dominated by significant warm spells, bushfires, and dryness, there is a bigger problem looming in the oceans around Australia.

This summer has outstripped long-term sea surface temperature records that extend back to the 1950s. We have seen warm surface temperatures all around Australia and across most of the Pacific and Indian oceans, with particularly warm temperatures in the southeast and northern Australian regions.

Last summer’s sea surface temperature rankings for Australia. Australian Bureau of MeteorologyLast summer’s sea surface temperature rankings for Australia. Australian Bureau of MeteorologyIn recent months, this warming has been boosted – just like land temperatures – by natural and human-caused climate factors.

Why so warm?

These record-breaking ocean temperatures around Australia are somewhat surprising. El Niño events, such as the one we’re currently experiencing, typically result in cooler than normal Australian waters during the second half of the year. So what is the cause?

The most likely culprit is a combination of local ocean and weather events, with a substantial contributor being human-caused climate change.

In the north, the recent weak monsoon season played a role in warming surface waters. Reduced cloud cover means more sunshine is able to pass through the atmosphere and heat the surface of the ocean. Trade winds that normally stir up the water and disperse the heat deeper into the ocean have also remained weak, leaving the warm water sitting at the surface.

In the south, the East Australian Current has extended further south over the summer. This warm current flows north to south down Australia’s east coast. Normally it takes a left turn and heads towards New Zealand, but this year it extended down to Tasmania, bringing warm waters to the south east.

This current is also getting stronger, transporting larger volumes of water southward over time. This is due to the southward movement of high pressure systems towards the pole.

High pressure systems are often associated with clear weather in Australia, and when they move south they prevent rain. This southward movement over time has also been linked to climate changes in our region, meaning that changes in both rainfall and ocean temperatures are responses to the same global factors.

We’ve also seen high ocean temperatures in the Indian Ocean. Around 2010, temperatures in the region suddenly jumped, likely because of the La Niña event in the Pacific Ocean. The strong events during this period transferred massive amounts of warmth from the Pacific Ocean into the Indian Ocean through the Indonesian region.

The warmer waters in the Indian Ocean have persisted since and have influenced land temperatures. The five years since the 2010 La Niña are the five hottest on record in southwest Western Australia (ranked 2011, 2015, 2014, 2013 and 2012).

What are the impacts?

The world’s oceans play a major role in global climate by absorbing surplus heat and energy. Oceans have absorbed 93% of the extra heat trapped by the Earth since 1970 as the greenhouse effect has increased. This has lowered the rate at which the atmosphere is warming – which is a good thing.

However, it also means the oceans are heating up, raising sea levels as well as leading to more indirect impacts, such as shifting rainfall patterns.

As a nation that likes to live by the coast as well as enjoy recreation activities and harvest produce from the sea, warmer-than-usual oceans can have significant impacts.

Australia derives a lot of its income from its oceans and while such impacts aren’t often seen immediately, they become apparent over time.

Warm sea temperatures this summer and in the past have seen declines in coral reef health, and strains on commercial fisheries and aquaculture. The Great Barrier Reef is currently experiencing coral bleaching amid very warm water temperatures.

Our neighbouring Pacific islands have also seen the impacts of these very high sea surface temperatures, with recent mass fish kills and coral bleaching episodes in Fiji.

The impacts of warmer ocean temperatures are also felt on land, as ocean temperatures drive climate and weather. Abnormally high sea surface temperatures may have contributed to the intensity of Cyclone Winston as cyclone potential intensity increases with ocean temperature.

What is the outlook?

The seasonal outlook from the Bureau of Meteorology shows El Niño weakening over the next few months. This typically means cooler weather and can mean more rain on land.

However, closer inspection shows surface temperatures over the entire Indian Ocean and coastal Australian waters will very likely continue to remain well above average for the next few months. There are currently signs that surface currents are moving warm El Niño waters from the eastern Pacific over to the western Pacific, towards Australia.

There is potential for the East Australian Current to continue to transport this warmth to southern waters as far as Tasmania. Warm water could also be transported through Indonesia and travel south along the Western Australian coast via the warm Leeuwin Current, potentially causing further warming of already record warm waters.

So for the near future, the waters are going to continue to be warm. That’s good news if you’re heading to the beach, but not so good for the environment.

About The Authors

Elaine Miles is a Ocean Climatologist within Climate and Ocean Data and Analysis Services at the Australian Bureau of Meteorology. Climate and Ocean Data and Analysis Services are responsible for publishing and analysing the climate record, including the ocean, in particular to advise on risk and related requirements. In particular, the group works closely with stakeholders on advanced climate requests.

Claire Spillman is a research scientist at the Bureau of Meteorology, Australia. Her current research is primarily focused on dynamical seasonal forecasting in marine applications, particularly for coral reef and fisheries management.

David Jones is Manager of Climate Monitoring and Prediction at the Australian Bureau of Meteorology.

David Walland is Head of Climate and Ocean Data and Analysis Services at the Australian Bureau of Meteorology.

This article originally appeared on The Conversation

Related Books:

InnerSelf Market

Amazon

enafarzh-CNzh-TWdanltlfifrdeiwhihuiditjakomsnofaplptruesswsvthtrukurvi

follow InnerSelf on

facebook icontwitter iconyoutube iconinstagram iconpintrest iconrss icon

 Get The Latest By Email

Weekly Magazine Daily Inspiration

EVIDENCE

Blue water surrounded by dead white grass
Map tracks 30 years of extreme snowmelt across US
by Mikayla Mace-Arizona
A new map of extreme snowmelt events over the last 30 years clarifies the processes that drive rapid melting.
White sea ice in blue water with the sun setting reflected in the water
Earth’s frozen areas are shrinking 33K square miles a year
by Texas A&M University
The Earth’s cryosphere is shrinking by 33,000 square miles (87,000 square kilometers) per year.
wind turbines
A controversial US book is feeding climate denial in Australia. Its central claim is true, yet irrelevant
by Ian Lowe, Emeritus Professor, School of Science, Griffith University
My heart sank last week to see conservative Australian commentator Alan Jones championing a contentious book about…
image
Reuters' Hot List of climate scientists is geographically skewed: why this matters
by Nina Hunter, Post-Doctoral Researcher, University of KwaZulu-Natal
The Reuters Hot List of “the world’s top climate scientists” is causing a buzz in the climate change community. Reuters…
A person holds a shell in their hand in blue water
Ancient shells hint past high CO2 levels could return
by Leslie Lee-Texas A&M
Using two methods to analyze tiny organisms found in sediment cores from the deep seafloor, researchers have estimated…
image
Matt Canavan suggested the cold snap means global warming isn't real. We bust this and 2 other climate myths
by Nerilie Abram, Professor; ARC Future Fellow; Chief Investigator for the ARC Centre of Excellence for Climate Extremes; Deputy Director for the Australian Centre for Excellence in Antarctic Science, Australian National University
Senator Matt Canavan sent many eyeballs rolling yesterday when he tweeted photos of snowy scenes in regional New South…
Ecosystem sentinels sound alarm for the oceans
by Tim Radford
Sea birds are known as ecosystem sentinels, warning of marine loss. As their numbers fall, so could the riches of the…
Why Sea Otters Are Climate Warriors
Why Sea Otters Are Climate Warriors
by Zak Smith
In addition to being one of the cutest animals on the planet, sea otters help maintain healthy, carbon-absorbing kelp…

LATEST VIDEOS

The Great Climate Migration Has Begun
The Great Climate Migration Has Begun
by Super User
The climate crisis is forcing thousands around the world to flee as their homes become increasingly uninhabitable.
The Last Ice Age Tells Us Why We Need To Care About A 2℃ Change In Temperature
The Last Ice Age Tells Us Why We Need To Care About A 2℃ Change In Temperature
by Alan N Williams, et al
The latest report from the Intergovernmental Panel on Climate Change (IPCC) states that without a substantial decrease…
Earth Has Stayed Habitable For Billions Of Years – Exactly How Lucky Did We Get?
Earth Has Stayed Habitable For Billions Of Years – Exactly How Lucky Did We Get?
by Toby Tyrrell
It took evolution 3 or 4 billion years to produce Homo sapiens. If the climate had completely failed just once in that…
How Mapping The Weather 12,000 Years Ago Can Help Predict Future Climate Change
How Mapping The Weather 12,000 Years Ago Can Help Predict Future Climate Change
by Brice Rea
The end of the last ice age, around 12,000 years ago, was characterised by a final cold phase called the Younger Dryas.…
The Caspian Sea Is Set To Fall By 9 Metres Or More This Century
The Caspian Sea Is Set To Fall By 9 Metres Or More This Century
by Frank Wesselingh and Matteo Lattuada
Imagine you are on the coast, looking out to sea. In front of you lies 100 metres of barren sand that looks like a…
Venus Was Once More Earth-like, But Climate Change Made It Uninhabitable
Venus Was Once More Earth-like, But Climate Change Made It Uninhabitable
by Richard Ernst
We can learn a lot about climate change from Venus, our sister planet. Venus currently has a surface temperature of…
Five Climate Disbeliefs: A Crash Course In Climate Misinformation
The Five Climate Disbeliefs: A Crash Course In Climate Misinformation
by John Cook
This video is a crash course in climate misinformation, summarizing the key arguments used to cast doubt on the reality…
The Arctic Hasn't Been This Warm For 3 Million Years and That Means Big Changes For The Planet
The Arctic Hasn't Been This Warm For 3 Million Years and That Means Big Changes For The Planet
by Julie Brigham-Grette and Steve Petsch
Every year, sea ice cover in the Arctic Ocean shrinks to a low point in mid-September. This year it measures just 1.44…

LATEST ARTICLES

green energy2 3
Four Green Hydrogen Opportunities for the Midwest
by Christian Tae
To avert a climate crisis, the Midwest, like the rest of the country, will need to fully decarbonize its economy by…
ug83qrfw
Major Barrier to Demand Response Needs to End
by John Moore, On Earth
If federal regulators do the right thing, electricity customers across the Midwest may soon be able to earn money while…
trees to plant for climate2
Plant These Trees To Improve City Life
by Mike Williams-Rice
A new study establishes live oaks and American sycamores as champions among 17 “super trees” that will help make cities…
north sea sea bed
Why We Must Understand Seabed Geology To Harness The Winds
by Natasha Barlow, Associate Professor of Quaternary Environmental Change, University of Leeds
For any country blessed with easy access to the shallow and windy North Sea, offshore wind will be key to meeting net…
3 wildfire lessons for forest towns as Dixie Fire destroys historic Greenville, California
3 wildfire lessons for forest towns as Dixie Fire destroys historic Greenville, California
by Bart Johnson, Professor of Landscape Architecture, University of Oregon
A wildfire burning in hot, dry mountain forest swept through the Gold Rush town of Greenville, California, on Aug. 4,…
China Can Meet Energy and Climate Goals Capping Coal Power
China Can Meet Energy and Climate Goals Capping Coal Power
by Alvin Lin
At the Leader’s Climate Summit in April, Xi Jinping pledged that China will “strictly control coal-fired power…
Blue water surrounded by dead white grass
Map tracks 30 years of extreme snowmelt across US
by Mikayla Mace-Arizona
A new map of extreme snowmelt events over the last 30 years clarifies the processes that drive rapid melting.
A plane drops red fire retardant on to a forest fire as firefighters parked along a road look up into the orange sky
Model predicts 10-year burst of wildfire, then gradual decline
by Hannah Hickey-U. Washington
A look at the long-term future of wildfires predicts an initial roughly decade-long burst of wildfire activity,…

 Get The Latest By Email

Weekly Magazine Daily Inspiration

New Attitudes - New Possibilities

InnerSelf.comClimateImpactNews.com | InnerPower.net
MightyNatural.com | WholisticPolitics.com | InnerSelf Market
Copyright ©1985 - 2021 InnerSelf Publications. All Rights Reserved.