15/01/2022

(The Conversation) Ocean Heat Is At Record Levels, With Major Consequences

The Conversation -

Author
Dr. Kevin Trenberth is a Distinguished Scholar at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, USA.
Dr. Trenberth is an affiliate faculty at the University of Auckland, New Zealand.
He studies climate variability and change.
The world witnessed record-breaking climate and weather disasters in 2021, from destructive flash floods that swept through mountain towns in Europe and inundated subway systems in China and the U.S., to heat waves and wildfires.

Typhoon Rai killed over 400 people in the Philippines; Hurricane Ida caused an estimated US$74 billion in damage in the U.S.

Globally, it was the sixth hottest year on record for surface temperatures, according to data released by NASA and the National Oceanic and Atmospheric Administration in their annual global climate report on Jan. 13, 2022.

But under the surface, ocean temperatures set new heat records in 2021.

As climate scientist Kevin Trenberth explains, while the temperature at Earth’s surface is what people experience day to day, the temperature in the upper part of the ocean is a better indicator of how excess heat is accumulating on the planet.

The Conversation spoke with Trenberth, coauthor of a study published on Jan. 11, 2022, by 23 researchers at 14 institutes that tracked warming in the world’s oceans.

A person carries a child's bike through flood water
A tropical storm’s rain overwhelmed a dam in Thailand and caused widespread flooding in late September. It was just one of 2021’s disasters. Chaiwat Subprasom/SOPA Images/LightRocket via Getty Images
Your latest research shows ocean heat is at record highs. What does that tell us about global warming?
The world’s oceans are hotter than ever recorded, and their heat has increased each decade since the 1960s. This relentless increase is a primary indicator of human-induced climate change.

As oceans warm, their heat supercharges weather systems, creating more powerful storms and hurricanes, and more intense rainfall. That threatens human lives and livelihoods as well as marine life.

The oceans take up about 93% of the extra energy trapped by the increasing greenhouse gases from human activities, particularly burning fossil fuels. Because water holds more heat than land does and the volumes involved are immense, the upper oceans are a primary memory of global warming.

I explain this in more detail in my new book “The Changing Flow of Energy Through the Climate System.”

Hurricane Ida making landfall on the Louisana coast
Hurricane Ida did $74 billion in damage from Louisiana to the Northeast in 2021. RAMMB/CIRA/Colorado State University

Our study provided the first analysis of 2021’s ocean warming, and we were able to attribute the warming to human activities. Global warming is alive and well, unfortunately.

The global mean surface temperature was the fifth or sixth warmest on record in 2021 (the record depends on the dataset used), in part, because of the year-long La Niña conditions, in which cool conditions in the tropical Pacific influence weather patterns around the world.

Ocean heat content in the upper 2,000 meters of the world’s oceans since 1958, relative to the 1981-2010 average. Ocean temperature records go back to the 1950s. The units are zettajoules. Lijing Cheng

There is a lot more natural variability in surface air temperatures than in ocean temperatures because of El Niño/La Niña and weather events.

That natural variability on top of a warming ocean creates hot spots, sometimes called “marine heat waves,” that vary from year to year.

Those hot spots have profound influences on marine life, from tiny plankton to fish, marine mammals and birds. Other hot spots are responsible for more activity in the atmosphere, such as hurricanes.

While surface temperatures are both a consequence and a cause, the main source of the phenomena causing extremes relates to ocean heat that energizes weather systems.

Scientists are concerned about the stability of Antarctica’s Thwaites Glacier, which holds back large amounts of land ice. NASA
We found that all oceans are warming, with the largest amounts of warming in the Atlantic Ocean and in the Southern Ocean surrounding Antarctica.

That’s a concern for Antarctica’s ice – heat in the Southern Ocean can creep under Antarctica’s ice shelves, thinning them and resulting in calving off of huge icebergs. Warming oceans are also a concern for sea level rise.

In what ways does extra ocean heat affect air temperature and moisture on land?

The global heating increases evaporation and drying on land, as well as raising temperatures, increasing risk of heat waves and wildfires. We’ve seen the impact in 2021, especially in western North America, but also amid heat waves in Russia, Greece, Italy and Turkey.

The warmer oceans also supply atmospheric rivers of moisture to land areas, increasing the risk of flooding, like the U.S. West Coast has been experiencing.

2021 saw several destructive cyclones, including Hurricane Ida in the U.S. and Typhoon Rai in the Philippines. How does ocean temperature affect storms like those?

Warmer oceans provide extra moisture to the atmosphere. That extra moisture fuels storms, especially hurricanes. The result can be prodigious rainfall, as the U.S. saw from Ida, and widespread flooding as occurred in many places over the past year.

The storms may also become more intense, bigger and last longer. Several major flooding events have occurred in Australia this past year, and also in New Zealand. Bigger snowfalls can also occur in winter provided temperatures remain below about freezing because warmer air holds more moisture.

A woman stands, arms crossed, staring at a car propped on its nose against a business after the typhoon.
A resident in the Philippines looks at a vehicle swept away by flood water during Typhoon Rai. Cheryl Baldicantos/AFP via Getty Images
If greenhouse gas emissions slowed, would the ocean cool down?

In the oceans, warm water sits on top of cooler denser waters. However, the oceans warm from the top down, and consequently the ocean is becoming more stratified. This inhibits mixing between layers that otherwise allows the ocean to warm to deeper levels and to take up carbon dioxide and oxygen. Hence it impacts all marine life.

We found that the top 500 meters of the ocean has clearly been warming since 1980; the 500-1,000 meter depths have been warming since about 1990; the 1,000-1,500 meter depths since 1998; and below 1,500 meters since about 2005.

The slow penetration of heat downward means that oceans will continue to warm, and sea level will continue to rise even after greenhouse gases are stabilized.

The final area to pay attention to is the need to expand scientists’ ability to monitor changes in the oceans.

One way we do this is through the Argo array – currently about 3,900 profiling floats that send back data on temperature and salinity from the surface to about 2,000 meters in depth, measured as they rise up and then sink back down, in ocean basins around the world.

These robotic, diving and drifting instruments require constant replenishment and their observations are invaluable.

Argo floats keep tabs on ocean changes around the world. Howard Freeland, 2018, CC BY-ND

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(AU ABC) Channel Country Gas Development Could Increase National Emissions By 60 Per Cent, Report Says

ABC News - Nathan Morris

A pattern of channels among green herbage and wildflowers near Windorah in July 2019.
The channels in Queensland's south west after flooding in 2019 — not far from where gas development is proposed. (ABC Southern Queensland: Nathan Morris)

Key Points
  • Professor Ian Lowe says emissions from a proposed Queensland gas development is incompatible with government pledges to cut carbon
  • The Queensland government says emissions reduction targets "are achievable"
  • "Fugitive emissions" in Queensland are the highest in the nation and "the long-term trend is increasing" 
A new report by a leading climate change expert has found that proposed gas development in the Lake Eyre Basin could increase Australia's total annual emissions by 60 per cent. 

Last month the ABC revealed that, without consulting traditional owner groups, the Queensland government had progressed plans for gas development in the environmentally fragile Channel Country, a vast system of flood plains in the state's south west.

A report, commissioned by environmental group Lock the Gate by leading climate change scientist Emeritus Professor Ian Lowe from Griffith University, modelled the potential carbon emissions if the gas projects in Queensland went ahead.

The Queensland component of the gas is in the Cooper-Eromanga Basin, and Professor Lowe found that if just 25 per cent of the resource was recovered, the emissions it would produce would be "incompatible" with Queensland's emission reduction targets.
"It would increase greenhouse gas emissions by about 60 per cent of Australia's current total national emissions from all sources: electricity, transport, manufacturing agriculture," he said.
"The high level of production would be about 300 million tonnes of carbon dioxide a year, and Australia's current total emissions from all causes is about 500 million tonnes a year."

An aerial shot of cattle grazing in a green paddock
The Channel Country's flood plains are home to a large sustainable grazing industry. (Supplied: OBE Organic)
The Queensland government has pledged to reduce emissions by 30 per cent of 2005 levels by 2030, but Professor Lowe's report found that even "the low export scenario would result in Scope 1 emissions alone that are more than 50 per cent of Queensland's proposed reduction of 31 million tonnes a year from all sources by 2030."

"Even a modest level of production would be incompatible with Queensland stated emission reduction targets," he said.

A map of locations in the Channel Country have production licences from Origin Energy
More than 250,000 hectares of land in the Channel Country is subject to Origin Energy's applications. (Supplied: Queensland Government)
Targets 'achievable'

But the Queensland government said its emissions targets were "achievable".
"In fact, Queensland achieved 20 per cent of its renewable energy target by 2020 and is almost halfway to reaching its 2030 emissions reduction target, having reduced emissions by 14 per cent since 2005," a spokesperson said.
Traditional owners call for a pause
on Channel Country fracking plans Birds eye view of the veins of the Kati Thanda-Lake Eyre basin river systems
The Lake Eyre Basin contains an estimated 334 trillion cubic feet of "unconventional gas", meaning to release the gas from the predominantly shale rock formation, gas wells would need to be depressurised by extracting groundwater or hydraulic fracturing, also known as fracking. 

There is concern among traditional owners and graziers in the area, but the Queensland government spokesperson said that additional approvals were still required before gas development could occur in the region, and they would be "subject to stringent assessment criteria".

Fugitive emissions

Professor Lowe said the Lake Eyre Basin contained high levels of additional CO2, which would be released directly into the atmosphere during gas extraction.

"The gas there contains significant amounts of carbon dioxide, so just producing the gas to be burned somewhere else would result in the release of significant amounts of carbon dioxide into the Australian atmosphere," he said.

A map of the Lake Eyre Basin
The Lake Eyre Basin covers large parts of four Australian states and territories. (ABC News: Alex Palmer)
The other factor was the "fugitive emissions" from gas production, the methane gas that either escapes or has to be vented from production pipelines for safety.

Queensland has the highest fugitive emissions from coal and gas mining in the nation, and they continue to rise.

A 2018 Queensland government report found fugitive emissions represented "11 per cent of Queensland's total emissions and the long-term trend is increasing emissions".

"Methane is a much more powerful greenhouse gas than carbon dioxide, and so the leakage, if gas were produced in the Channel Country, would add significantly to our greenhouse gas production locally," Professor Lowe said.
"In typical natural gas fields, about 5 per cent of the gas leaks into the atmosphere, in some bad cases at 7 or 8 per cent."
A coal seam gas well and all of the piping and water extraction infrastructure.
Coal seam gas mining is widespread further east of the Channel Country, and criss-crosses farm land. (ABC Southern Queensland: Nathan Morris)

A spokesperson for the Queensland government said it had a plan to reduce fugitive emissions.

"The Palaszczuk government has committed in its draft 30-year-plan for the resources industry to work with industry to investigate ways to reduce fugitive emissions from resource activities, particularly in the Bowen Basin," they said.
"It also expects industry to reduce emissions, including fugitive emissions."
'Making enormous money'

After gas prices fell during 2020, international demand for the resource has rebounded, and the International Energy Agency forecasts more growth in the coming years.

"All these gas companies at the moment are trying to produce as much gas and ship as much gas as they possibly can," Bruce Robertson said, an Energy Finance Analyst with the Institute for Energy Economics and Financial Analysis (IEEFA).

"Even if it's not contracted gas, they're making enormous money on it."

Coal seam gas wells near Chinchilla
Coal seam gas wells in an area south of Chinchilla in southern Qld, near the Tara residential estate. (AAP: Supplied)

However, last year another report from the International Energy Agency said:
"Beyond projects already committed as of 2021, there are no new oil and gas fields approved for development in our pathway [to net-zero], and no new coal mines or mine extensions are required."
Mr Robertson said this was at odds with the continued enthusiasm for fossil fuel projects in Australia.

"In every state and territory, we're seeing new areas opened up for exploration by the current governments," he said.

"We're seeing this massive expansion of the gas industry, which is entirely inconsistent with any climate commitments."

While demand for gas remained strong now, Mr Robertson thought that would change.
"The change is very rapid when it occurs, and all the factors are in place for that change to occur in gas and when it comes it will come very quickly," he said.
"In New South Wales, for example, the state where I live, there are 17 battery projects, grid-scale battery projects in the planning system right now." 

Resources a major economic driver

Farmer welcomes CSG Farmer Ian Hayllor stands near gas drilling rig on his farm near Dalby in June 2021.

A report in December 2021 by the Federal Department of Resources found oil and gas projects "accounted for the largest share of committed projects by value".

The Queensland government also reports that the resources industry directly employs around 80,000 people in the state.

And according to Australian Petroleum Production and Exploration Association (APPEA), liquefied natural gas (LNG) and oil projects generated $13.20 billion in royalties and contributed $55 billion to national GDP. 

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(Radio New Zealand) Climate Change: 'One In 50-Year Event Is Now One In 10-Year Event', Says Scientist


New Zealand had the hottest national average temperature last year, but the single highest temperature recorded in the country remains unbeaten.

No caption
Photo: RNZ / Cosmo Kentish-Barnes

National Institute of Water and Atmospheric Research's (NIWA) annual climate report was released yesterday, with Canterbury's Rangiora holding onto a near 50-year record of 42.4C.

Last year's highest recorded temperature was 39.4C in Ashburton.

Weather events exacerbated by climate change are thought to be bringing a hotter, drier climate to Aotearoa's shores.

NIWA meteorologist Nava Fedaeff said a hot north-westerly wind from Australia was key to scorching days.

"Canterbury is often the place where we see the hottest temperatures and that's because of our friends, the Southern Alps," Fedaeff said.

"The recipe for our hottest temperatures recorded is usually a north westerly wind flow coming from Australia."

As the wind blows over the Southern Alps, it heats the other side in a process called the Foehn Effect, creating warm, dry conditions on the east coast.

Fedaeff said the phenomenon was common knowledge to locals.

"Anyone living on the east coast of the South Island is very familiar with a nor'wester wind."

This wind is expected to become more frequent, thanks to climate change, and could bring more droughts to the Canterbury Plains.

At the beginning of the year many parts of Canterbury were drought stricken.
Many parts of Canterbury were drought-stricken at the beginning of 2017. Photo: RNZ / Patrick Phelps

Manaaki Whenua - Landcare Research senior scientist Nick Cradock-Henry said more work was needed to adapt the country to new climate conditions.

Dr Cradock-Henry believes "there's no going back."

"There's a certain amount of change that is essentially 'baked' into the climate change system ... we need to put a greater emphasis on adaptation," he said.

Extreme rainfall events, floods, droughts and coastal erosion would effect Canterbury, he said, but he believed local councils were so far responding well.

"In Canterbury, regional councils have a significant responsibility and certainly Environment Canterbury and Christchurch City Council have both been stepping up.

"Thirty-year investment decisions need to take a much longer view ... We need to be recognising the one in 50-year event is now the one in ten-year event."

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