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中国国家主席习近平于2020年承诺在2060年前实现碳中和,此后中国围绕能源转型的思路发生了巨大转变。

然而,尽管此后中国出台了一系列重大政策,但目前仍不明确什么是新的能源系统,以及中国实现碳中和目标的最有效途径是什么。

我们的最新研究为中国能源转型建立了三种情景模型:一种是中国在2055年前建立净零排放的能源系统;一种是中国在2055年左右实现这一目标;还有一种是推断当前发展趋势的基线情景。

我们发现,将能效措施、终端用能消费电气化和基于各种可再生能源(如太阳能和风能)的低碳电力供应结合起来,可以极大地帮助该国在2055年前实现脱碳目标。

在最高情景下,中国的电力部门到2055年将不使用化石燃料,而一些行业将继续使用少量煤炭和天然气。然而,配备碳捕集与封存技术的生物质发电厂所产生的负排放将对此起到平衡作用。

双碳目标如何改变局势

2020年9月,当习近平开始在联合国大会上发表演讲时,几乎无人预料到中国会发表如此具有开创性的宣言。

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他说:“中国将力争2030年前实现碳达峰、2060年前实现碳中和。”

这一政策现在更多地被称为“双碳”目标。

这句话改变了人们对中国能源转型的整体认识。

在此之前,中国在2017年“十九大”上的目标是“要推进能源生产和消费革命,构建清洁低碳、安全高效的能源体系。”

而习近平在2020年的讲话将中国的优先发展从实现“低碳”转变为实现“碳中和”,使能源部门从至少包括部分化石燃料消费,转变为一旦实现碳中和就几乎不给煤炭、石油和天然气留下空间。

要实现这一转变,需要处于中国政策体系和能源系统的利益相关者,如主要发电企业,真正改变思维方式。

中国在宣布碳中和目标后立即开始行动:国务院推出了“1+N”政策体系,其中包括实现“双碳”目标的总体纲领性文件(“1”)和实施该战略的一系列更具体的指导方针和法规(“N”)。

到目前为止,这些政策主要侧重于在2030年之前实现碳达峰。不过,在2060年之前实现碳中和的长期目标始终存在。

国家能源局发布了一份新型电力系统发展蓝皮书。在更广泛的层面上,多个政府部门已提出要为实现碳中和而推动整个能源系统——而不仅仅是电力系统——进行转型。

因此,今天中国能源转型的基础比习近平宣布之前更加坚实和精确。现在的问题是:新型能源系统将是什么样子,中国将如何实现这一目标?

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中国能源转型的三种情景

为了回答这些问题,我们的研究模拟了中国能源转型的三种情景:一种是中国在2055年前建立一个净零排放的能源系统;一种是中国在2055年左右实现这一目标;还有一种是推断当前发展趋势的基线情景。

该分析基于一种详细的自下而上的建模方法,同时将“美丽中国”愿景——实现“绿色和高质量增长”的官方倡议——作为转型的指导方针。

在我们的模型中,能源转型的总体战略包括三个紧密相连的行动:

  1. 提高整个供应链的能源效率;
  2. 尽可能使终端用能部门电气化;
  3. 将电力部门转变为以太阳能和风能为支柱的“绿色”、无化石能源部门。

(政府间气候变化专门委员会的最新评估报告显示,这些是将升温控制在1.5°C或2°C的所有全球路径的关键要素。)

遵循这一战略的结果是,中国的能源系统将能够为中国可持续的经济增长提供动能,同时实现净零碳排放、空气质量改善和高水平的能源安全。

在最高情景下,中国的电力系统将从2045年起实现碳中和,整个能源系统将在2055年前实现碳中和。

与今天的情况相比,尽管经济有所增长,但2060年的一次能源消费总量将有所下降。此外,煤炭、石油和天然气将几乎被逐步淘汰,对进口化石燃料的依赖将被消除。

下图显示了2021年中国经济的能流(上图)与2060年在最高情景下的能流(下图)的对比。

在左侧,各版块显示了流入经济的一次能源来源,如煤炭(黑色)、天然气(粉红色)、石油(灰色),以及非化石燃料,如核能(棕色)、水能(深蓝色)、风能(浅蓝色)和太阳能(黄色)。

各版块的中心都显示了一次能源转化为更有用形式的过程,如电力或精炼油产品。化石燃料中所含的大部分一次能源在这一阶段以废热的形式被浪费(“损失”)。

右侧是按部门划分的最终能源用户。

最值得注意的是,化石燃料(尤其是煤炭)是2021年最大的能源来源,而在雄心勃勃的2060年情景(见下图)中,低碳能源则占主导地位。

China Energy Flow Chart
China Energy Flow Chart
Left: Sources of primary energy in China. Centre: Transformation of primary energy into more useful forms. Right: Users of final energy by sector. Top panel: Energy flows in 2021. Bottom: 2060. Credit: ERI (2023).

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中国能源转型的三个阶段

我们的研究表明,转型之路将分为三个主要阶段。第一阶段是2030年前的碳达峰。

在此期间,风电和光伏发电的部署将继续增加,同时工业和交通部门的电气化也将取得进展。

然而,就一次能源消费总量而言,煤炭和石油仍将是最主要的初级能源消费。

接下来是“能源革命”阶段,从2030年到2050年。在这一阶段,光电和风电将成为电力供应的主要来源,终端用能部门的电气化程度将大幅提高。

摒弃化石燃料可以最大限度地减少发电和提炼过程中的废热损失。同时,利用可再生能源生产的“绿氢”在工业领域将变得越来越重要。

第三阶段是巩固阶段,从2050年到2060年。脱碳发生在钢铁和化工等难以实现电气化的细分部门,旧的风光发电厂将被新的风光发电厂取代,能源组合中剩余的化石燃料几乎被淘汰。

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煤电成为灵活性提供者

虽然中国政府计划从2025年起“逐步淘汰”煤炭,但根据当前的政策方针和市场情况,我们估计在三种情景中,煤电装机都不会迅速消失。

相反,燃煤电厂将逐渐成为保障能源安全和满足电力需求高峰的能力提供者,而不再进行大量发电。

当燃煤电厂达到30年左右的预期寿命时就将被关闭,而不会被新的煤电装机所取代。如下图所示,在我们最高情景中,最后一批煤电厂将于2055年关闭。

图中上半部分显示了2021年至2060年燃煤电厂的装机容量,下半部分显示了燃煤电厂的发电量。

煤炭装机容量在21世纪20年代末达峰,然后平缓下降
燃煤发电在2030年达峰,于2055年下降至26TWh
Top: coal power capacity 2021-2060, gigawatts. Bottom: coal power generation 2021-2060, terawatt hours. Credit: ERI (2023)

与此同时,在我们的情景中,天然气在电力部门作用有限。这是因为光电和风电可以提供更便宜的电力,而现有的燃煤电厂——加上储能和需求侧响应设施的大规模扩张——足以提供灵活性和调峰能力。

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管理由多变的风电和光电主导的电网

依赖光电和风电作为主要电力来源的能源系统,需要采取特殊的灵活性措施促成供需有效匹配。

下图显示了在2055年前实现碳中和的雄心勃勃的情景下,2060年夏季一周内每小时电力平衡的模拟示例。

图中上半部分显示的是供应侧发电量。在白天,光电(黄色)在电力生产中占主导地位,而风电厂(浅蓝)在24小时内都有更稳定的输出。

在傍晚和夜间,储能(紫色)会被释放,水力发电量(深蓝)高于白天。

图中下半部分显示的是需求侧的用电情况。储能(紫色)在白天充电,电动汽车智能充电(蓝色)在一周内提供灵活性。

A safe, efficient, and green electricity system dominated by wind and solar power
Top: Electricity supply on a hypothetical summer week in 2060. Bottom: Electricity demand. Credit: ERI (2023)

作为后备电源,电动汽车车网互动发挥着重要作用——其不一定是重要的能源供应商,而是在风电和光电输出有限时,成为必要时可以启用的最后手段。该方案是保证电力系统容量充足的一种经济、高效的方法。

在2055年之前,煤电厂同样可能是电力系统可靠且经济的容量提供者,尽管如前所述,其平均发电量并不高。

从日常调度(管理供需的过程)的角度来看,这种创造灵活性的方式似乎很复杂。然而,一个高效且运作良好的电力市场(包括消费者和生产者)可以做到这一点。

消除各省之间的电力交易障碍、构建全国统一的电力市场,将是实现这一目标的关键因素。

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未来远景规划

我们在《中国能源转型展望》(China Energy Transformation Outlook)中的情景对净零排放能源系统的长期未来提供了一系列量化远景规划。

我们对电力系统和其他能源终端用能部门建立了详细的模型,从而可以将这一新能源系统的发展与实现这一转变的政策措施联系起来。

我们研究得出的一个关键结论与上述中国能源转型不同阶段的时机有关。我们的模型表明,成功协调这些阶段至关重要,这样才能在保持能源安全的同时避免对能源基础设施进行不必要的投资。

我们情景中的其他关键推动因素包括扩大电网所需投资、国家电力市场的发展和对能源系统灵活性的支持。

即使有最优的远景规划和从我们的路径中获得的洞见,中国要实现2060年的目标仍有许多需要克服的挑战和障碍。

然而,我们的情景表明,有一些可行且具有成本效益的路径可以在不等待新技术突破的情况下实施。

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The post 嘉宾来稿:中国能源系统如何在2055年前实现碳中和 appeared first on Carbon Brief.

嘉宾来稿:中国能源系统如何在2055年前实现碳中和

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The 2026 budget test: Will Australia break free from fossil fuels?

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In 2026, the dangers of fossil fuel dependence have been laid bare like never before. The illegal invasion of Iran has brought pain and destruction to millions across the Middle East and triggered a global energy crisis impacting us all. Communities in the Pacific have been hit especially hard by rising fuel prices, and Australians have seen their cost-of-living woes deepen.

Such moments of crisis and upheaval can lead to positive transformation. But only when leaders act with courage and foresight.

There is no clearer statement of a government’s plans and priorities for the nation than its budget — how it plans to raise money, and what services, communities, and industries it will invest in.

As we count down the days to the 2026-27 Federal Budget, will the Albanese Government deliver a budget for our times? One that starts breaking the shackles of fossil fuels, accelerates the shift to clean energy, protects nature, and sees us work together with other countries towards a safer future for all? Or one that doubles down on coal and gas, locks in more climate chaos, and keeps us beholden to the whims of tyrants and billionaires.

Here’s what we think the moment demands, and what we’ll be looking out for when Treasurer Jim Chalmers steps up to the dispatch box on 12 May.

1. Stop fuelling the fire
2. Make big polluters pay
3. Support everyone to be part of the solution
4. Build the industries of the future
5. Build community resilience
6. Be a better neighbour
7. Protect nature

1. Stop fuelling the fire

Action Calls for a Transition Away From Fossil Fuels in Vanuatu. © Greenpeace
The community in Mele, Vanuatu sent a positive message ahead of the First Conference on Transitioning Away from Fossil Fuels. © Greenpeace

In mid-April, Pacific governments and civil society met to redouble their efforts towards a Fossil Fuel Free Pacific. Moving beyond coal, oil and gas is fundamental to limiting warming to 1.5°C — a survival line for vulnerable communities and ecosystems. And as our Head of Pacific, Shiva Gounden, explained, it is “also a path of liberation that frees us from expensive, extractive and polluting fossil fuel imports and uplifts our communities”.

Pacific countries are at the forefront of growing global momentum towards a just transition away from fossil fuels, and it is way past time for Australia to get with the program. It is no longer a question of whether fossil fuel extraction will end, but whether that end will be appropriately managed and see communities supported through the transition, or whether it will be chaotic and disruptive.

So will this budget support the transition away from fossil fuels, or will it continue to prop up coal and gas?

When it comes to sensible moves the government can make right now, one stands out as a genuine low hanging fruit. Mining companies get a full rebate of the excise (or tax) that the rest of us pay on diesel fuel. This lowers their operating costs and acts as a large, ongoing subsidy on fossil fuel production — to the tune of $11 billion a year!

Greenpeace has long called for coal and gas companies to be removed from this outdated scheme, and for the billions in savings to be used to support the clean energy transition and to assist communities with adapting to the impacts of climate change. Will we see the government finally make this long overdue change, or will it once again cave to the fossil fuel lobby?

2. Make big polluters pay

Activists Disrupt Major Gas Conference in Sydney. © Greenpeace
Greenpeace Australia Pacific activists disrupted the Australian Domestic Gas Outlook conference in Sydney with the message ‘Gas execs profit, we pay the price’. © Greenpeace

While our communities continue to suffer the escalating costs of climate-fuelled disasters, our Government continues to support a massive expansion of Australia’s export gas industry. Gas is a dangerous fossil fuel, with every tonne of Australian gas adding to the global heating that endangers us all.

Moreover, companies like Santos and Woodside pay very little tax for the privilege of digging up and selling Australians’ natural endowment of fossil gas. Remarkably, the Government currently raises more tax from beer than from the Petroleum Resource Rent Tax (PRRT) — the main tax on gas profits.

Momentum has been building to replace or supplement the PRRT with a 25% tax on gas exports. This could raise up to $17 billion a year — funds that, like savings from removing the diesel tax rebate for coal and gas companies, could be spent on supporting the clean energy transition and assisting communities with adapting to worsening fires, floods, heatwaves and other impacts of climate change.

As politicians arrive in Canberra for budget week, they will be confronted by billboards calling for a fair tax on gas exports. The push now has the support of dozens of organisations and a growing number of politicians. Let’s hope the Treasurer seizes this rare window for reform.

3. Support everyone to be part of the solution

As the price of petrol and diesel rises, electric vehicles (EVs) are helping people cut fuel use and save money. However, while EV sales have jumped since the invasion of Iran sent fuel prices rising, they still only make up a fraction of total new car sales. This budget should help more Australians switch to electric vehicles and, even more importantly, enable more Australians to get around by bike, on foot, and on public transport. This means maintaining the EV discount, investing in public and active transport, and removing tax breaks for fuel-hungry utes and vans.

Millions of Australians already enjoy the cost-saving benefits of rooftop solar, batteries, and getting off gas. This budget should enable more households, and in particular those on lower incomes, to access these benefits. This means maintaining the Cheaper Home Batteries Program, and building on the Household Energy Upgrades Fund.

4. Build the industries of the future

Protest of Woodside and Drill Rig Valaris at Scarborough Gas Field in Western Australia. © Greenpeace / Jimmy Emms
Crew aboard Greenpeace Australia Pacific’s campaigning vessel the Oceania conducted a peaceful banner protest at the site of the Valaris DPS-1, the drill rig commissioned to build Woodside’s destructive Burrup Hub. © Greenpeace / Jimmy Emms

If we’re to transition away from fossil fuels, we need to be building the clean industries of the future.

No state is more pivotal to Australia’s energy and industrial transformation than Western Australia. The state has unrivaled potential for renewable energy development and for replacing fossil fuel exports with clean exports like green iron. Such industries offer Western Australia the promise of a vibrant economic future, and for Australia to play an outsized positive role in the world’s efforts to reduce emissions.

However, realising this potential will require focussed support from the Federal Government. Among other measures, Greenpeace has recommended establishing the Australasian Green Iron Corporation as a joint venture between the Australian and Western Australian governments, a key trading partner, a major iron ore miner and steel makers. This would unite these central players around the complex task of building a large-scale green iron industry, and unleash Western Australia’s potential as a green industrial powerhouse.

5. Build community resilience

Believe it or not, our Government continues to spend far more on subsidising fossil fuel production — and on clearing up after climate-fuelled disasters — than it does on helping communities and industries reduce disaster costs through practical, proven methods for building their resilience.

Last year, the Government estimated that the cost of recovery from disasters like the devastating 2022 east coast floods on 2019-20 fires will rise to $13.5 billion. For contrast, the Government’s Disaster Ready Fund – the main national source of funding for disaster resilience – invests just $200 million a year in grants to support disaster preparedness and resilience building. This is despite the Government’s own National Emergency Management Agency (NEMA) estimating that for every dollar spent on disaster risk reduction, there is a $9.60 return on investment.

By redirecting funds currently spent on subsidising fossil fuel production, the Government can both stop incentivising climate destruction in the first place, and ensure that Australian communities and industries are better protected from worsening climate extremes.

No communities have more to lose from climate damage, or carry more knowledge of practical solutions, than Aboriginal and Torres Strait Islander peoples. The budget should include a dedicated First Nations climate adaptation fund, ensuring First Nations communities can develop solutions on their own terms, and access the support they need with adapting to extreme heat, coastal erosion and other escalating challenges.

6. Be a better neighbour

The global response to climate change depends on the adequate flow of support from developed economies like Australia to lower income nations with shifting to clean energy, adapting to the impacts of climate change, and addressing loss and damage.

Such support is vital to building trust and cooperation, reducing global emissions, and supporting regional and global security by enabling countries to transition away from fossil fuels and build greater resilience.

Despite its central leadership role in this year’s global climate negotiations, our Government is yet to announce its contribution to international climate finance for 2025-2030. Greenpeace recommends a commitment of $11 billion for this five year period, which is aligned with the global goal under the Paris Agreement to triple international climate finance from current levels.
This new commitment should include additional funding to address loss and damage from climate change and a substantial contribution to the Pacific Resilience Facility, ensuring support is accessible to countries and communities that need it most. It should also see Australia get firmly behind the vision of a Fossil Fuel Free Pacific.

7. Protect nature

Rainforest in Tasmania. © Markus Mauthe / Greenpeace
Rainforest of north west Tasmania in the Takayna (Tarkine) region. © Markus Mauthe / Greenpeace

There is no safe planet without protection of the ecosystems and biodiversity that sustain us and regulate our climate.

Last year the Parliament passed important and long overdue reforms to our national environment laws to ensure better protection for our forests and other critical ecosystems. However, the Government will need to provide sufficient funding to ensure the effective implementation of these reforms.

Greenpeace has recommended $500 million over four years to establish the National Environment Agency — the body responsible for enforcing and monitoring the new laws — and a further $50 million to Environment Information Australia for providing critical information and tools.

Further resourcing will also be required to fulfil the crucial goal of fully protecting 30% of Australian land and seas by 2030. This should include $1 billion towards ending deforestation by enabling farmers and loggers to retool away from destructive practices, $2 billion a year for restoring degraded lands, $5 billion for purchasing and creating new protected areas, and $200 million for expanding domestic and international marine protected areas.

Conclusion

This is not the first time that conflict overseas has triggered an energy crisis, or that a budget has been preceded by a summer of extreme weather disasters, highlighting the urgent need to phase out fossil fuels. What’s different in 2026 is the availability of solutions. Renewable energy is now cheaper and more accessible than ever before. Global momentum is firmly behind the transition away from fossil fuels. The Albanese Government, with its overwhelming majority, has the chance to set our nation up for the future, or keep us stranded in the past. Let’s hope it makes some smart choices.

The 2026 budget test: Will Australia break free from fossil fuels?

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What fossil fuels really cost us in a world at war

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Anne Jellema is Executive Director of 350.org.

The war on Iran and Lebanon is a deeply unjust and devastating conflict, killing civilians at home, destroying lives, and at the same time sending shockwaves through the global economy. We, at 350.org, have calculated, drawing on price forecasts from the International Monetary Fund (IMF) and Goldman Sachs, just how much that volatility is costing us. 

Even under the IMF’s baseline scenario – a de facto “best case” scenario with a near-term end to the war and related supply chain disruptions – oil and gas price spikes are projected to cost households and businesses globally more than $600 billion by the end of the year. Under the IMF’s “adverse scenario”, with prolonged conflict and sustained price pressures, we estimate those additional costs could exceed $1 trillion, even after accounting for reduced demand.

Which is why we urgently need a power shift. Governments are under growing pressure to respond to rising fuel and food costs and deepening energy poverty. And it’s becoming clearer to both voters and elected officials that fossil dependence is not only expensive and risky, but unnecessary. 

People who can are voting with their wallets: sales of solar panels and electric vehicles are increasing sharply in many countries. But the working people who have nothing to spare, ironically, are the ones stuck with using oil and gas that is either exorbitantly expensive or simply impossible to get.

Drain on households and economies

In India, street food vendors can’t get cooking gas and in the Philippines, fishermen can’t afford to take their boats to sea. A quarter of British people say that rising energy tariffs will leave them completely unable to pay their bills. This is the moment for a global push to bring abundant and affordable clean energy to all.

In April, we released Out of Pocket, our new research report on how fossil fuels are draining households and economies. We were surprised by the scale of what we found. For decades, governments have reassured people that energy price spikes are unfortunate but unavoidable – the result of distant conflicts, market forces or geopolitical shocks beyond anyone’s control. But the numbers tell a different story. 

    What we are living through today is not an energy crisis. It is a fossil fuel crisis. In just the first 50 days of the Middle East conflict, soaring oil and gas prices have siphoned an estimated $158 billion–$166 billion from households and businesses worldwide. That is money extracted directly from people’s pockets and transferred, almost instantly, into fossil fuel company balance sheets. And this figure only captures the immediate impact of price spikes, not the permanent economic drain of fossil dependence. Fossil fuels don’t just cost us once, they cost us over and over again.

    First, through our bills. Every time there is a war, an embargo or a supply disruption, fossil fuel prices surge. For ordinary people, this means higher costs for energy, transport and food. Many Global South countries have little or no fiscal space to buffer the shock; instead, workers and families pay the price.

    Second, through our taxes. Governments around the world continue to pour vast sums of public money into fossil fuel subsidies. These are often justified as a way to protect the most vulnerable at the petrol pump or in their homes. But in reality, the benefits are overwhelmingly captured by wealthier households and corporations. The poorest 20% receive just a fraction of this support, while public finances are drained.

    Third, through climate impacts. New research across more than 24,000 global locations gives a granular account of the true costs of extreme heat, sea level rise and falling agricultural yields. Using this data to update IMF modelling of the social cost of carbon, we found that fossil fuel impacts on health and livelihoods amount to over $9 trillion a year. This is the biggest subsidy of all, because these massive and mounting costs are not charged to Big Oil – they are paid for by governments and households, with the poorest shouldering the lion’s share. 

    Massive transfer of wealth to fossil fuel industry

    Adding up direct subsidies, tax breaks and the unpaid bill for climate damages, the total transfer of wealth from the public to the fossil fuel industry amounts to $12 trillion even in a “normal” year without a global oil shock. That’s more than 50% higher than the IMF has previously estimated, and equivalent to a staggering $23 million a minute.

    The fossil fuel industry has become extraordinarily adept at profiting from instability. When conflict drives up prices, companies do not lose, they gain. In the current crisis, oil producers and commodity traders are on track to secure tens of billions of dollars in additional windfall profits, even as households face rising bills and governments struggle to manage the fallout.

    Fossil fuel crisis offers chance to speed up energy transition, ministers say

    This growing disconnect is impossible to ignore. Investors are advised to buy into fossil fuel firms precisely because of their ability to generate profits in times of crisis. Meanwhile, ordinary people are told to tighten their belts.

    In 2026, unlike during the oil shocks of the 1970s, clean energy is no longer a distant alternative. Now, even more than when gas prices spiked due to Russia’s invasion of Ukraine in 2022, renewables are often the cheapest option available. Solar and wind can be deployed quickly, at scale, and without the volatility that defines fossil fuel markets.

    How to transition from dirty to clean energy

    The solutions are clear. Governments must implement permanent windfall taxes on fossil fuel companies to ensure that extraordinary profits generated during crises are redirected to support households. These revenues can be used to reduce energy bills, invest in public services, and accelerate the rollout of clean energy.

    Second, we must shift subsidies away from fossil fuels and towards renewable solutions, particularly those that can be deployed quickly and equitably, such as rooftop and community solar. This is not just about cutting emissions. It is about building a more stable, fair and resilient energy system.

    Finally, we need binding plans to phase out fossil fuels altogether, replacing them with homegrown renewable energy that can shield economies from future shocks. Because what the current crisis has made clear is this: as long as we remain dependent on fossil fuels, we remain vulnerable – to conflict, to price volatility and to the escalating impacts of climate change.

    The true price of fossil fuels is no longer hidden. It is visible in rising bills, strained public finances and communities pushed to the brink. And it is being paid, every day, by ordinary people around the world.

    It’s time for the great power shift

    Full details on the methodology used for this report are available here.

    The Great Power Shift is a new campaign by 350.org global campaign to pressure governments to bring down energy bills for good by ending fossil fuel dependence and investing in clean, affordable energy for all

    Logo of 350.org campaign on “The Great Power Shift”

    Logo of 350.org campaign on “The Great Power Shift”

    The post What fossil fuels really cost us in a world at war appeared first on Climate Home News.

    What fossil fuels really cost us in a world at war

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    Climate Change

    Traditional models still ‘outperform AI’ for extreme weather forecasts

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    Computer models that use artificial intelligence (AI) cannot forecast record-breaking weather as well as traditional climate models, according to a new study.

    It is well established that AI climate models have surpassed traditional, physics-based climate models for some aspects of weather forecasting.

    However, new research published in Science Advances finds that AI models still “underperform” in forecasting record-breaking extreme weather events.

    The authors tested how well both AI and traditional weather models could simulate thousands of record-breaking hot, cold and windy events that were recorded in 2018 and 2020.

    They find that AI models underestimate both the frequency and intensity of record-breaking events.

    A study author tells Carbon Brief that the analysis is a “warning shot” against replacing traditional models with AI models for weather forecasting “too quickly”.

    AI weather forecasts

    Extreme weather events, such as floods, heatwaves and storms, drive hundreds of billions of dollars in damages every year through the destruction of cropland, impacts on infrastructure and the loss of human life.

    Many governments have developed early warning systems to prepare the general public and mobilise disaster response teams for imminent extreme weather events. These systems have been shown to minimise damages and save lives.

    For decades, scientists have used numerical weather prediction models to simulate the weather days, or weeks, in advance.

    These models rely on a series of complex equations that reproduce processes in the atmosphere and ocean. The equations are rooted in fundamental laws of physics, based on decades of research by climate scientists. As a result, these models are referred to as “physics-based” models.

    However, AI-based climate models are gaining popularity as an alternative for weather forecasting.

    Instead of using physics, these models use a statistical approach. Scientists present AI models with a large batch of historical weather data, known as training data, which teaches the model to recognise patterns and make predictions.

    To produce a new forecast, the AI model draws on this bank of knowledge and follows the patterns that it knows.

    There are many advantages to AI weather forecasts. For example, they use less computing power than physics-based models, because they do not have to run thousands of mathematical equations.

    Furthermore, many AI models have been found to perform better than traditional physics-based models at weather forecasts.

    However, these models also have drawbacks.

    Study author Prof Sebastian Engelke, a professor at the research institute for statistics and information science at the University of Geneva, tells Carbon Brief that AI models “depend strongly on the training data” and are “relatively constrained to the range of this dataset”.

    In other words, AI models struggle to simulate brand new weather patterns, instead tending forecast events of a similar strength to those seen before. As a result, it is unclear whether AI models can simulate unprecedented, record-breaking extreme events that, by definition, have never been seen before.

    Record-breaking extremes

    Extreme weather events are becoming more intense and frequent as the climate warms. Record-shattering extremes – those that break existing records by large margins – are also becoming more regular.

    For example, during a 2021 heatwave in north-western US and Canada, local temperature records were broken by up to 5C. According to one study, the heatwave would have been “impossible” without human-caused climate change.

    The new study explores how accurately AI and physics-based models can forecast such record-breaking extremes.

    First, the authors identified every heat, cold and wind event in 2018 and 2020 that broke a record previously set between 1979 and 2017. (They chose these years due to data availability.) The authors use ERA5 reanalysis data to identify these records.

    This produced a large sample size of record-breaking events. For the year 2020, the authors identified around 160,000 heat, 33,000 cold and 53,000 wind records, spread across different seasons and world regions.

    For their traditional, physics-based model, the authors selected the High RESolution forecast model from the Integrated Forecasting System of the European Centre for Medium-­Range Weather Forecasts. This is “widely considered as the leading physics-­based numerical weather prediction model”, according to the paper.

    They also selected three “leading” AI weather models – the GraphCast model from Google Deepmind, Pangu-­Weather developed by Huawei Cloud and the Fuxi model, developed by a team from Shanghai.

    The authors then assessed how accurately each model could forecast the extremes observed in the year 2020.

    Dr Zhongwei Zhang is the lead author on the study and a researcher at Karlsruhe Institute of Technology. He tells Carbon Brief that many AI weather forecast models were built for “general weather conditions”, as they use all historical weather data to train the models. Meanwhile, forecasting extremes is considered a “secondary task” by the models.

    The authors explored a range of different “lead times” – in other words, how far into the future the model is forecasting. For example, a lead time of two days could mean the model uses the weather conditions at midnight on 1 January to simulate weather conditions at midnight on 3 January.

    The plot below shows how accurately the models forecasted all extreme events (left) and heat extremes (right) under different lead times. This is measured using “root mean square error” – a metric of how accurate a model is, where a lower value indicates lower error and higher accuracy.

    The chart on the left shows how two of the AI models (blue and green) performed better than the physics-based model (black) when forecasting all weather across the year 2020.

    However, the chart on the right illustrates how the physics-based model (black) performed better than all three AI models (blue, red and green) when it came to forecasting heat extremes.

    Accuracy of the AI models
    Accuracy of the AI models (blue, red and green) and the physics-based model (black) at forecasting all weather over 2020 (left) and heat extremes (right) over a range of lead times. This is measured using “root mean square error” (RMSE) – a metric of how accurate a model is, where a lower value indicates lower error and higher accuracy. Source: Zhang et al (2026).

    The authors note that the performance gap between AI and physics-based models is widest for lower lead times, indicating that AI models have greater difficulty making predictions in the near future.

    They find similar results for cold and wind records.

    In addition, the authors find that AI models generally “underpredict” temperature during heat records and “overpredict” during cold records.

    The study finds that the larger the margin that the record is broken by, the less well the AI model predicts the intensity of the event.

    ‘Warning shot’

    Study author Prof Erich Fischer is a climate scientist at ETH Zurich and a Carbon Brief contributing editor. He tells Carbon Brief that the result is “not unexpected”.

    He adds that the analysis is a “warning shot” against replacing traditional models with AI models for weather forecasting “too quickly”.

    The analysis, he continues, is a “warning shot” against replacing traditional models with AI models for weather forecasting “too quickly”.

    AI models are likely to continue to improve, but scientists should “not yet” fully replace traditional forecasting models with AI ones, according to Fischer.

    He explains that accurate forecasts are “most needed” in the runup to potential record-breaking extremes, because they are the trigger for early warning systems that help minimise damages caused by extreme weather.

    Leonardo Olivetti is a PhD student at Uppsala University, who has published work on AI weather forecasting and was not involved in the study.

    He tells Carbon Brief that “many other studies” have identified issues with using AI models for “extremes”, but this paper is novel for its specific focus on extremes.

    Olivetti notes that AI models are already used alongside physics-based models at “some of the major weather forecasting centres around the world”. However, the study results suggest “caution against relying too heavily on these [AI] models”, he says.

    Prof Martin Schultz, a professor in computational earth system science at the University of Cologne who was not involved in the study, tells Carbon Brief that the results of the analysis are “very interesting, but not too surprising”.

    He adds that the study “justifies the continued use of classical numerical weather models in operational forecasts, in spite of their tremendous computational costs”.

    Advances in forecasting

    The field of AI weather forecasting is evolving rapidly.

    Olivetti notes that the three AI models tested in the study are an “older generation” of AI models. In the last two years, newer “probabilistic” forecast models have emerged that “claim to better capture extremes”, he explains.

    The three AI models used in the analysis are “deterministic”, meaning that they only simulate one possible future outcome.

    In contrast, study author Engelke tells Carbon Brief that probabilistic models “create several possible future states of the weather” and are therefore more likely to capture record-breaking extremes.

    Engelke says it is “important” to evaluate the newer generation of models for their ability to forecast weather extremes.

    He adds that this paper has set out a “protocol” for testing the ability of AI models to predict unprecedented extreme events, which he hopes other researchers will go on to use.

    The study says that another “promising direction” for future research is to develop models that combine aspects of traditional, physics-based weather forecasts with AI models.

    Engelke says this approach would be “best of both worlds”, as it would combine the ability of physics-based models to simulate record-breaking weather with the computational efficiency of AI models.

    Dr Kyle Hilburn, a research scientist at Colorado State University, notes that the study does not address extreme rainfall, which he says “presents challenges for both modelling and observing”. This, he says, is an “important” area for future research.

    The post Traditional models still ‘outperform AI’ for extreme weather forecasts appeared first on Carbon Brief.

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