19/02/2021

Ford Plans For All Cars Sold In Europe To Be Electric By 2030

The Guardian - 

US firm to spend $1bn converting plant in Cologne to become its first electric vehicle facility in Europe

Ford’s first all-electric cars will start rolling off the production line at its plant in Cologne, Germany, in 2023.Photograph: Friedemann Vogel/EPA 
Ford has pledged that all of its cars on sale in Europe will be electric by 2030, in the latest move by the world’s biggest auto manufacturers to set out plans to move away from polluting internal combustion engines before looming bans on fossil-fuel vehicles across the world. 

The US car giant said on Wednesday that it was going “all in” on electric vehicles and would invest $1bn (£720m) converting a vehicle assembly plant in Cologne, Germany, to become its first electric vehicle facility in Europe.

It said the first all-electric cars would start rolling off the production line there in 2023.

Ford promised that all of its passenger cars in Europe would be “zero-emissions capable all-electric or plug-in hybrid” by mid-2026, before ramping up its ambitions to be “completely all-electric by 2030”. “We are charging into an all-electric future in Europe with expressive new vehicles and a world-class connected customer experience,” Stuart Rowley, the head of Ford’s European operations, said.

“Our announcement today to transform our Cologne facility, the home of our operations in Germany for 90 years, is one of the most significant Ford has made in over a generation.

“It underlines our commitment to Europe and a modern future with electric vehicles at the heart of our strategy for growth.”

Ford said two-thirds of its commercial vehicles would also be all-electric or plug-in hybrid by 2030.

The company dominates the US and European markets for petrol-powered commercial vehicles with a 40% and 15% share of the markets, respectively. Ford said its commercial vehicle business was “key to future growth and profitability.”

The carmaker, which returned to profit in Europe last year, has formed an alliance with Volkswagen to use its modular electric drive electric vehicle platform to build some models. The Cologne facility will use the VW platform.

This month Ford said it was “doubling down” on electric vehicles (EVs) and would invest at least $22bn in electrification by 2025, nearly twice the company’s previous EV ambitions.

This week Jaguar Land Rover, the UK-based carmaker owned by India’s Tata Motors, said its luxury Jaguar brand cars would be electric-only by 2025 and it would abandon petrol vehicles entirely in the middle of the next decade.

Ford’s Detroit rival General Motors aims to have an entirely zero-emission lineup by 2035.

The plans come as car companies race to transform their business to meet strict CO2 emission targets set by governments across the world.

The UK has announced a ban on the sale of new cars and vans powered wholly by petrol and diesel from 2030.

It is part of Boris Johnson’s call for a “green industrial revolution” to tackle the climate crisis and create new jobs in future technologies. The UK has set a target to be a net zero emissions economy by 2050.

EU environment ministers struck a deal in October to make the bloc’s 2050 net zero emissions target legally binding.

Norway, which relies heavily on oil and gas revenues, aims to become the world’s first country to end the sale of fossil-fuel-powered cars, setting a 2025 deadline. Fully electric vehicles make up about 60% of monthly sales in Norway.

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(AU) More Than 100 Australian Plant Species Entirely Burnt In Black Summer Bushfires, Study Finds

The Guardian - 

CSIRO-led research estimates 100 entire populations were burnt and another 816 had more than half their area burnt

The Gondwana rainforest burning in the Nightcap national park during Australia’s Black Summer. Fears that rare and ancient rainforest plants are now further threatened have been confirmed by a study. Photograph: Darcy Grant/The Guardian

More than 100 plant species had their entire populations burned in the Black Summer bushfires, according to the most detailed study yet of the impact on Australia’s plants.

An estimated 816 species had at least half the areas they grow burned, according to estimates in the study, and some ecosystems are now at risk of “regeneration failure”.

While many of the species studied are adapted to recover from fire – either by reshooting or growing from seeds waiting dormant in nearby soils – there are fears that the loss of mature plants has left some species and entire ecosystems vulnerable.

CSIRO researcher and lead author of the study Dr Bob Godfree and 14 other researchers published their analysis, which used satellite data to map the fires, in the journal Nature Communications.

The fires, which burned at least 7.5m hectares of eucalyptus forests in the south-east of the continent, had left rainforest species particularly exposed.

“To have so much burn in such a short period of time was quite staggering,” Godfree said.

He said plants underpinned the function of entire ecosystems, providing food and shelter for wildlife and stabilising soils, as well as storing carbon.

“Changes in vegetation is natural over very long time frames, but if that change occurs very rapidly it can be disruptive,” he said.

Researchers analysed data from four satellites alongside more than 1.4m records of plants in south-east Australia across forests, woodlands, healthlands, grasslands, shrublands and in and around rainforests.

The research said: “All known populations of an estimated 116 species (14% of the total) burnt, which is more than double the number of plant species endemic to the British Isles.”

Fears that rare and ancient plants in Australia’s network of Gondwana rainforest reserves were now further threatened were confirmed, the study said.

Godfree said one group of rainforest plants particularly vulnerable were known as epiphytic orchids, which grow on trees rather than on the ground.

“They’re killed by fires, especially crown fires, and they don’t have much of a seed bank,” he said.

Some 251 plant species in the study were highly adapted to fire and had traits to recover, such as the ability to sprout from burnt trunks or underground tubers, store seeds in nearby soils or have seeds that germinated after exposure to smoke or heat.

But another 122 species that in theory could persist after fire were considered vulnerable because of invasive disease like myrtle rust, grazing from invasive species like deer, and more intense droughts.

Godfree said: “The impacts of these fires was certainly unprecedented in their scale. They impacted more plant species in a single fire season since anything that’s happened since European settlement, possibly longer.”

Importantly, Godfree said, the fires burned across wide areas and across species that were already being affected by changes to climate.

The study warns there is emerging evidence globally that catastrophic fire events have the ability to trigger tipping points, where forests are replaced with other vegetation.

Much of the vegetation affected by the fires was already under stress from extreme drought and record high temperatures which, the study said, could alone drive major changes.

More research was needed to find out if some forests were undergoing “regenerative failure”, the study concluded.

Plant ecologist Dr Rod Fensham, of the University of Queensland, who was not an author of the research, said the study was “impressive” but said the reported impacts on rainforest species needed further study.

He said: “We ecologists are on edge and nervous about what the meteorologists are telling us about these events and how they’re going to get more frequent.”

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New Tree-Loving Robots Could Plant Entire Forest Of Seeds Daily

Interesting Engineering - 

The robots work in tandem, one clears up the site from vegetation and the other one plants. 

Renders of Milrem Robotics' Planter and Brushcutter robots. Provided by Milrem Robotics

Estonia's University of Tartu and Milrem Robotics have collaborated to develop two types of autonomous robot foresters that have the capacity to plant thousands of trees a day using driverless technology.

One of the robots is a planter, the other is a brushcutter. Both are the size of a small car and can work in tandem, New Scientist reports. 

Milrem Robotics' brushcutter and forester robots

The Multiscope Forester Planter is equipped with a modular "planting payload with a capacity of 380 seedlings," Milrem Robotics explains on its website. The company also points out that their robot was "designed for a temperate climate zone," meaning it isn't quite equipped for harsh terrain or weather.

The Multiscope Forester Brushcutter, meanwhile, was designed to be "rugged and long-lasting in challenging environments like clear-cut areas."

The system is equipped with Milrem Robotics' Multiscope platform, which is equipped with a power unit (Max. pressure: 250 bar, Oil flow: 70 l/min), a brush cutting tool, and sensors.

An older Milrem Robotics model using the company's Multiscope platform, Source: Provided by Milrem Robotics

Advanced LiDAR systems for autonomous navigation

Both of the machines travel at about 12 mph (20 km/h), enabling the Forester Planter to have a planting speed of approximately 5-6.5 hours per hectare (2.5 acres) depending on the species of tree and the type of terrain.  

The two robots can be used in tandem, with the brushcutter trimming vegetation around seedlings or clearing our space for the Planter robot.

Both of the robots navigate via laser-based LiDAR, cameras, and global positioning systems (GPS). LiDAR produces a three-dimensional geometric representation of the robots' environments, enabling them to navigate autonomously.

Mobile robotics technology is maturing fast

Andrew Davidson at the U.K.'s Imperial College London told New Scientist, "this is one of many interesting applications ... which show that mobile robotics technology is maturing fast and enabling robots to tackle new types of task in difficult environments."

The makers of Sophia the Robot recently cited a rise in the use of robots amid the pandemic as a motivation for their bold future plans and many other companies also capitalizing on the recent surge in automation.

Milrem Robotics and the University of Tartu are utilizing their expertise in the rising field of robotics for the equally important sector of sustainability.

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18/02/2021

(NZ) As NZ Gets Serious About Climate Change, Can Electricity Replace Fossil Fuels In Time?

The Conversation - 

Concrete spillway from Lake Benmore Dam in Otago, New Zealand. Shutterstock

Author
Dr Jen Purdie is Senior Research Fellow, University of Otago.
As fossil fuels are phased out over the coming decades, the Climate Change Commission (CCC) suggests electricity will take up much of the slack, powering our vehicle fleet and replacing coal and gas in industrial processes.

But can the electricity system really provide for this increased load where and when it is needed? The answer is “yes”, with some caveats.

Our research examines climate change impacts on the New Zealand energy system. It shows we’ll need to pay close attention to demand as well as supply. And we’ll have to factor in the impacts of climate change when we plan for growth in the energy sector.

Demand for electricity to grow

While electricity use has not increased in NZ in the past decade, many agencies project steeply rising demand in coming years. This is partly due to both increasing population and gross domestic product, but mostly due to the anticipated electrification of transport and industry, which could result in a doubling of demand by mid-century.

The graph (below), based on a range of projections from various agencies, shows demand may increase by between 10TWh and 60TWh (Terawatt hours) by 2050. This is on top of the 43TWh of electricity currently generated per year to power the whole country.


SOURCES: Historical generation data, Meridian Energy Ltd, internal modelling, Transpower, MBIE, BEC, CCC.

It’s hard to get a sense of the scale of the new generation required, but if wind was the sole technology employed to meet demand by 2050, between 10 and 60 new wind farms would be needed nationwide.

Of course, we won’t only build wind farms. Grid-scale solar, rooftop solar, new geothermal, some new small hydro plant and possibly tidal and wave power will all have a part to play.

We will need more wind farms. Shutterstock/Joshua Daniel

Managing the demand

As well as providing more electricity supply, demand management and batteries will also be important. Our modelling shows peak demand (which usually occurs when everyone turns on their heaters and ovens at 6pm in winter) could be up to 40% higher by 2050 than it is now.

But meeting this daily period of high demand could see expensive plant sitting idle for much of the time (with the last 25% of generation capacity only used about 10% of the time).

This is particularly a problem in a renewable electricity system when the hydro lakes are dry, as hydro is one of the few renewable electricity sources that can be stored during the day (as water behind the dam) and used over the evening peak (by generating with that stored water).

Demand response will therefore be needed. For example, this might involve an industrial plant turning off when there is too much load on the electricity grid.

But by 2050, a significant number of households will also need smart appliances and meters that automatically use cheaper electricity at non-peak times. For example, washing machines and electric car chargers could run automatically at 2am, rather than 6pm when demand is high.

Our modelling shows a well set up demand response system could mitigate dry-year risk (when hydro lakes are low on water) in coming decades, where currently gas and coal generation is often used.

Instead of (or as well as) having demand response and battery systems to combat dry-year risk, a pumped storage system could be built. This is where water is pumped uphill when hydro lake inflows are plentiful, and used to generate electricity during dry periods.

The NZ Battery project is currently considering the potential for this in New Zealand.

Almost (but not quite) 100% renewable

Dry-year risk would be greatly reduced and there would be “greater greenhouse gas emissions savings” if the Interim Climate Change Committee’s (ICCC) 2019 recommendation to aim for 99% renewable electricity was adopted, rather than aiming for 100%.

A small amount of gas-peaking plant would therefore be retained. The ICCC said going from 99% to 100% renewable electricity by overbuilding would only avoid a very small amount of carbon emissions, at a very high cost.

Our modelling supports this view. The CCC’s draft advice on the issue also makes the point that, although 100% renewable electricity is the “desired end point”, timing is important to enable a smooth transition.

Despite these views, Energy Minister Megan Woods has said the government will be keeping the target of a 100% renewable electricity sector by 2030.

Minister of Energy and Resources Megan Woods speaking at the Tiwai Point aluminium smelter, due to close in 2024. Getty Images
Impacts of climate change

In future, the electricity system will have to respond to changing climate patterns as well. The National Institute of Water and Atmospheric Research predicts winds will increase in the South Island and decrease in the far north in coming decades.

Inflows to the biggest hydro lakes will get wetter (more rain in their headwaters), and their seasonality will change due to changes in the amount of snow in these catchments.

Our modelling shows the electricity system can adapt to those changing conditions. One good news story (unless you’re a skier) is that warmer temperatures will mean less snow storage at lower elevations, and therefore higher lake inflows in the big hydro catchments in winter, leading to a better match between times of high electricity demand and higher inflows.

The price is right

The modelling also shows the cost of generating electricity is not likely to increase, because the price of building new sources of renewable energy continues to fall globally.

Because the cost of building new renewables is now cheaper than non-renewables (such as coal-fired plants), renewables are more likely to be built to meet new demand in the near term.

While New Zealand’s electricity system can enable the rapid decarbonisation of (at least) our transport and industrial heat sectors, certainty is needed in some areas so the electricity industry can start building to meet demand everywhere.

Bipartisan cooperation at government level will be important to encourage significant investment in generation and transmission projects with long lead times and life expectancies.

Infrastructure and markets are needed to support demand response uptake, as well as certainty around the Tiwai exit in 2024 and whether pumped storage is likely to be built.

Our electricity system can support the rapid decarbonisation needed if New Zealand is to do its fair share globally to tackle climate change.

But sound planning, firm decisions and a supportive and relatively stable regulatory framework are all required before shovels can hit the ground.

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Why Manufacturing Is The Biggest Hurdle In Climate Change Fight

Al Jazeera - News Agencies

Bill Gates says governments and investors need to find ways to reduce emissions from steel- and cement-making. 

Manufacturing, especially of the cheap construction staples steel and cement, accounts for about a third of global greenhouse gas emissions. [File: George Frey/Bloomberg]

US billionaire Bill Gates exudes optimism in discussing the world’s ability to tackle climate change – until he hits on manufacturing. About that, he is worried.

There is currently no way to make steel or cement without releasing climate-warming emissions. Yet neither governments nor investors are looking hard to solve that problem, Gates told the Reuters news agency.

“That’s the sector that bothers me the most,” Gates said in a video interview with Reuters ahead of the publication this week of his book: How to Avoid a Climate Disaster.

The software-developer-turned-philanthropist has invested about $2bn towards the development of clean technologies. But those investments are mostly in electricity generation and storage.

Manufacturing – especially of the cheap construction staples steel and cement – accounts for about a third of global greenhouse gas emissions. That makes manufacturing more polluting than the power or transportation sectors, which receive far more attention in policies and investments. And the manufacturing sector is set to grow, as the global population climbs and countries further develop.

‘The easy stuff’

“People still need basic shelter, certainly in developing countries,” said Gates, co-founder of Microsoft Corp. “It’s unlikely we’ll stop building buildings.”

Gates plans to push for more research and innovation at the UN climate conference in Glasgow in November. “The idea is to get innovation, including R&D, onto the agenda … not just looking at the easy stuff.”

During the 2015 United Nations climate talks in Paris, Gates helped to launch a global initiative called Mission Innovation along with United States former President Barack Obama, French former President Francois Hollande and Indian Prime Minister Narendra Modi to link national governments with the private sector in pursuing and sharing clean technology.

The manufacture of steel and cement for the construction industry release carbon dioxide as a byproduct. [File: Thomas Mukoya/Reuters]

We need “total coordination, and, in fact, some overlap is a very good thing to have,” Gates told Reuters. But he said there should be diversity in the solutions being sought so governments do not end up duplicating efforts. 

Right now, for example, “they’re doing a lot of green hydrogen products,” Gates said. “But who’s doing the hard stuff?”

Some manufacturing plants may be able to lower their emissions by plugging into an electricity grid run on renewable energy. But that will not solve all emissions from steel- and cement-making, both processes that release carbon dioxide as a byproduct.

Yo yo-ing energy policies

In the US it has not helped to have energy policy yo-yo between presidential administrations, he said. “This stop-start approach, that’s too risky for the private sector.”

On a personal note, Gates says in his book that, after years of dismissing activists’ calls to divest from fossil fuels, he sold his direct holdings in oil and gas companies in 2019. The Gates Foundation’s endowment did the same – but not because Gates became convinced that divestment would push companies towards clean energy.

Rather: “I don’t want to profit if their stock prices go up because we don’t develop zero-carbon alternatives,” he writes. “I’d feel bad if I benefitted from a delay in getting to zero.”

But Gates does still have interests in some polluting industries.

An investment firm Gates controls, Cascade Investment LLC, recently offered to increase its stake in Signature Aviation Plc, the world’s biggest operator of private-jet bases. Private jets typically pump out far more carbon emissions per passenger on each trip than flying commercial.

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Do We Need More Scary Climate Change Articles? Maybe.

Grist - 

Grist

Every time a bleak, adrenaline-inducing article goes viral, the so-called “hope vs. fear” dispute rages on Twitter. The most recent conversation starter was Elizabeth Weil’s intimate profile in ProPublica of Peter Kalmus, a climate scientist whose death-spiraling dread was taking over his life — his whole family’s life, really.

With the title “The Climate Crisis Is Worse Than You Can Imagine. Here’s What Happens If You Try,” the piece was bound to get attention — and criticism. Why not highlight a more productive way to cope with the climate crisis? people asked.

Weil seemed to anticipate this debate, which has remained contentious at least since David Wallace-Wells’ “The Uninhabitable Earth” made a splash in 2017. Near the end of the piece, Weil asks, “How do you describe an intolerable problem in a way that listeners — even you, dear reader — will truly let in?”

It’s a tough question, and experts are split over the right response. “Some people believe that we should emphasize the risks and generate fear and that many people are not scared enough yet,” said Jennifer Marlon, a research scientist at the Yale Program on Climate Change Communication. “And then other people think we really need to just focus on solutions.”

The debate is about more than just rhetoric; it’s about how people should feel about climate change. “When we’re specifically trying to promote action on climate, we know that one of the best ways to do that is to emotionally engage people in it,” Marlon said.

The problem is, reading lots of scary articles might make one person take to the streets in protest, but lead someone else to disengage and shut down. There are an infinite variety of ways to respond to and talk about the climate crisis.

Studies have come to wildly different conclusions. One paper will proclaim that “Fear Won’t Do It” for motivating action on climate change; another will say the exact opposite. The research about hope is similarly mixed.

Some studies have suggested that optimistic messages could prod people to behave in more climate-friendly ways and increase support for climate policies, but others found that hopeful appeals actually lowered people’s motivation to reduce emissions.

“It’s really cut down the middle,” said Joshua Ettinger, a PhD student studying public support for climate action at the University of Oxford. “You have study after study finding conflicting results.”

Ettinger’s new research, published in the journal Climatic Change, suggests that the whole “hope vs. fear” argument might be overblown. For the experiment, 500 Americans were shown different videos meant to evoke either hopeful or fearful reactions to climate change. (One group got a message along the lines of “Humanity can stop climate change and create a better world for all!”; the others heard, “Unless we take major action, humanity is doomed.”)

While both videos evoked the intended emotions, in the end, neither one altered people’s willingness to change their behavior or participate in climate activism.

“We’re so caught up in how a single message captures the narrative,” Ettinger said, but “we shouldn’t necessarily assume that a single piece of content is going to dramatically influence people.”

Americans are not a monolithic mass; they respond to global warming with alarm, concern, caution, denial, and everything in between, sometimes all in the same day. A 2017 article argued against making broad, simplistic assertions about how specific emotions will change people’s response to the climate crisis.

Emotions are powerful, but they’re not “simple levers to be pulled,” the authors argued. Still, Marlon said, there are patterns in how people respond.

Some research suggests that while fear can prompt us to spring into action, hope actually gives us something to do. In other words, alarming and optimistic messages could simply be two sides of the same coin.

Margaret Klein Salamon, the founder of The Climate Mobilization, argues that “telling the whole, frightening truth” is a powerful asset for the climate movement that could unlock “tremendous potential for transformation” — provided that it’s paired with an ambitious, heroic solution.

Her organization calls for “an all-hands-on-deck effort to eliminate greenhouse gas emissions and safely draw down excess carbon from the atmosphere at emergency speed.”

This attitude is reflected in different ways across the spectrum of activist groups: While Extinction Rebellion focuses on doom, groups like the Sunrise Movement, inspired by the Green New Deal, emphasize an optimistic narrative about jobs and justice. What they share is a driving sense of urgency.

Salamon sees fear as a useful tool, an innate, protective mechanism that demands a response. The terror you feel when someone yells “snake!” shakes you out of complacency and primes you to spring into action … even if that action is simply running away.

“I don’t see how we could possibly achieve the scale of transformation we need if there’s not a shared national understanding that this is an existential threat, that this is a terrible danger,” Salamon said. “If people don’t think that, why would they change their lives? Why would they be part of a political movement? It’s always struck me as kind of an odd position, that somehow we can accomplish huge-scale change but without ever really telling the public the truth.”

Too much doom and gloom, however, can backfire, leading people to deny threats and ignore distressing facts. People are rightfully concerned about exaggeration and “the kind of doomism that says there’s nothing we can do to stop climate change,” Ettinger said.

According to a recent survey from the Yale Program on Climate Change Communication, 14 percent of Americans think it’s too late to do anything about climate change (for the record, it isn’t).

A number of studies suggest that fear-based messages are persuasive and can change people’s behavior, particularly when they’re paired with messages that empower people to take action rather than wallow in misery.

Marlon has found that what gives people hope around climate change is seeing others take action. That could be a neighbor putting up solar panels, a friend talking about climate change, or Swedish activist Greta Thunberg skipping school in protest of government inaction.

One recent study found that people who had heard of Thunberg said they were more likely to participate in activism, a phenomenon called the “Greta effect.” “You can’t just sit around waiting for hope to come,” Thunberg told European leaders in 2019. “Then you are acting like spoiled irresponsible children. You don’t seem to understand that hope is something that you have to earn.”

Despite all the debate over hope and fear, the mix of messages people are hearing about the climate crisis seems to be resonating with a growing share of the public.

Watching a single video or reading a single article isn’t likely to have a lasting effect on people, Marlon said, but “the slow and steady drip, drip, drip of messages” is, along with people seeing change with their own eyes.

Today, more than a quarter of Americans are alarmed about the climate crisis, twice as high as it was five years ago. “The messaging is working,” Marlon said. “And there are lots of emotions mixed up in there, but we’re going in the right direction.”

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17/02/2021

Sea Level Data Confirms Climate Modeling Projections Were Right

University of New South Wales - Lachlan Gilbert

Projections of rising sea levels this century are on the money when tested against satellite and tide-gauge observations, scientists find.

The IPCC says sea levels could rise around 30-60 cm by 2100 even if greenhouse gas emissions are sharply reduced and global warming is limited to well below 2°C, but around 60-110 cm if greenhouse gas emissions continue to increase strongly. Photo: "Rising sea levels" by go_greener_oz is licensed under CC BY-ND 2.0

Climate model projections of sea-level rises in the early 21st century are in good agreement with sea level data recorded in the corresponding period, a recent analysis has found.

And the scientists who crunched the numbers say the finding does not bode well for sea level impacts over coming decades if greenhouse gas emissions are not reined in.

In an article published recently in Nature Communications, the scientists from Chinese and Australian institutions including UNSW Sydney examined the global and regional sea level projections of two reports by the Intergovernmental Panel on Climate Change: the Fifth Assessment Report (AR5) and Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC).

They compared the reports’ projections with the observed global and coastal sea level data gathered from satellites and a network of 177 tide-gauges from the start of the projections in 2007 up to to 2018. 

The scientists found that the trends of the AR5 and SROCC sea level projections under three different scenarios of greenhouse gas emissions “agree well with satellite and tide-gauge observations over the common period 2007–2018, within the 90 per cent confidence level”.



Study co-author and leading sea-level expert, Professor John Church, says while he thought the projections from modelling would be accurate at the global level, he was pleasantly surprised that they were as accurate at the regional and local level.

“Our analysis implies that the models are close to observations and builds confidence in the current projections for the next several decades,” says Prof. Church, who is part of UNSW’s Climate Change Research Centre.

But he adds a caveat that because the available comparison period is short, at just 11 years, he would be hesitant to extend the same degree of confidence over the longer term – from the end of this century and beyond – where acceleration of ice-sheet contribution to sea-level rise is less understood and could lead to larger rises.

“There remains a potential for larger sea level rises, particularly beyond 2100 for high emission scenarios. Therefore, it is urgent that we still try to meet the commitments of the Paris Agreement by significantly reducing emissions,” Prof. Church says.

Study co-author Dr Xuebin Zhang, from CSIRO’s Oceans and Atmosphere Division says this is the first study to compare projections of sea level rises at both a global and regional level with observations over their overlapping periods – no mean feat given the natural variability of climate and vertical land movement from region to region.

“We carefully removed the impacts from natural climate variability, for example El Niño– Southern Oscillation, and corrected vertical land movement, which led to much improved agreement.”

The analysis looked at the three different emissions scenarios in the IPCC’s reports that corresponded to three different climate futures depending on what greenhouse gas mitigation strategies were adopted – known as Representative Concentration Pathway (RCP) scenarios.

The lowest scenario (RCP2.6) examined is for strong mitigation of greenhouse gas emissions, about in line with 2oC of global warming by 2100 but still larger than what is required to meet the Paris Agreement of well below 2oC.

The middle scenario (RCP4.5) requires stabilisation of radiative forcing in the latter half of this century and results in warming well above the Paris Target.

And the highest scenario (RCP8.5) is for large greenhouse gas emissions resulting in ongoing rapid warming and implies a commitment to large sea level rises.

“The analysis of the recent sea level data indicate the world is tracking between RCP4.5 and the worst case scenario of RCP8.5,” Professor Church says.

“If we continue with large ongoing emissions as we are at present, we will commit the world to metres of sea level rise over coming centuries.”

Next the group will attempt to gain a greater understanding of the processes determining regional sea level rise.

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