Positive Climate Stories in September
From renewables overtaking coal for the first time in history to a landmark treaty protecting the world’s oceans, September delivered real progress. This edition celebrates legal milestones, cleaner cities and corporate climate action.
Legal story of the month
1. From court ruling to climate action: ICJ AO already making impact
On 23 July 2025, the International Court of Justice (ICJ) issued its advisory opinion on states’ obligations in respect of climate change (the AO). The ICJ confirmed that all countries bear responsibilities and can be held legally accountable for climate harm.
Positive enough? Yes, but the pursuit of climate justice doesn’t end there. Advisory opinions are not binding but should set a legal baseline, guiding acceptable state practice, shaping international negotiations and signalling consequences for inaction. The AO’s impact depends on translating legal clarity into real-world climate action – and this work is already underway:
Vanuatu leverages the AO: Hours after delivery, Vanuatu’s climate minister Ralph Regenvanu condemned Australia’s continued fossil fuel activities and excessive emissions. The AO determined such projects are an internationally wrongful act. More than that, it exposes major emitters to liability and potential reparations and empowers vulnerable states with legal leverage to demand climate accountability.
Shell under fire: A South African High Court halted Shell’s offshore drilling after challenge from Natural Justice. Citing the ICJ, it ruled international law requires impact assessments where an activity poses a risk of transboundary harm. This also speaks to the role of companies in fuelling the climate crisis – the ICJ found liability for corporate actions under states’ control.
Our Children’s Trust et al v. United States: Former Juliana plaintiffs petitioned the Inter-American Commission on Human Rights, alleging US fossil fuel policy breaches their rights and access to justice. The challengeextensively applies the ICJ AO, including the causation test to establish an internationally wrongful act in causing significant harm to the climate system.
Resolution and cooperation: Coming full circle, Vanuatu is seeking a second climate resolution at the UN General Assembly (the first being the request for the ICJ AO back in 2023). This resolution will seek to transform the AO into “workable obligations” and stands to represent what the climate crisis demands: international cooperation.
2. Renewables overtake coal in historic global energy milestone
For the first time in history, the world's wind and solar farms have generated more electricity than coal plants, marking a fundamental shift in the global power system.
In the first half of 2025, solar power led the charge with spectacular growth – nearly a third more generation than the same period in 2024, meeting 83% of the world's increased electricity needs. This marks the beginning of a shift where clean power is keeping pace with demand growth. Wind power contributed too with 7% growth, allowing renewables to displace fossil fuels for the first time.
The transformation is being driven by developing nations. China added more renewable capacity than the rest of the world combined, leading to a 2% drop in fossil fuel use. India grew its renewables three times faster than electricity demand, causing coal and gas use to fall by 3.1% and 34% respectively.
Solar costs have plummeted 99.9% since 1975, fuelling explosive growth in emerging markets. Pakistan imported solar panels capable of generating 17 gigawatts in 2024 – equivalent to a third of the country's current electricity generation capacity. Africa's panel imports surged 60% year-on-year, with South Africa leading and Nigeria's 1.7GW capacity equivalent to meeting electricity demand of 1.8m European homes.
China's dominance in clean technology – producing 60% of the world's wind turbines and 80% of solar panels – has made renewables more competitive globally. According to Ember, 91% of newly commissioned wind and solar projects are now cheaper than fossil fuel equivalents.
3. Landmark agreement to protect High Seas becomes international law
A global agreement to protect the world's oceans and reverse damage to marine life is set to become international law.
Decades of overfishing, pollution from shipping and warming have severely damaged our oceans and their inhabitants. Nearly 10% of marine species are now at risk of extinction, according to the International Union for Conservation of Nature (IUCN).
The issue is acute in the high seas – international waters beyond any countries’ control – where everyone has the right to ship and fish. Currently, only 1% is protected, leading to overexploitation of the rest of the high seas.
In 2023, countries agreed that 30% of the world's international waters must become Marine Protected Areas by 2030 to help depleted marine life recover. However, the treaty required ratification by 60 countries to take effect. That threshold was reached in September when Morocco became the 60th signatory, meaning the treaty will come into force in January 2026.
Unfortunately, the UK hasn’t ratified yet but could soon – parliament introduced a bill for ratification last month.
This is a historic achievement. The High Seas Treaty is the first legal framework protecting biodiversity in international waters, which cover nearly two-thirds of the ocean and nearly half of Earth’s surface. It establishes binding rules for conservation, and once active, countries will propose and vote on protected areas.
Protecting our ocean is key to our survival. Oceans provide up to 80% of our oxygen and contribute an estimated £1.9tn to the global economy.
4. Toxic air pollution in London drops to legal levels
Toxic nitrogen dioxide pollution (NO2) in London’s air has fallen within the legal limit for the first time since it was introduced in 2010.
NO2 is a toxic gas known to exacerbate asthma and impede lung development. It’s one of several air pollutants measured and regulated under UK laws. In 2019, experts at King’s College London estimated that without further action, it would take 193 years for London to meet government-set limits
So how did London reach this target 184 years early? This is largely due to ultra-low emission zones (Ulez). The Ulez scheme, introduced in 2019, requires drivers of the most polluting cars to pay a £12.50 daily charge. The zone was then extended across the whole of Greater London in August 2023, creating the world’s biggest pollution charging zone.
According to a City Hall report earlier this year, there were nearly 100,000 fewer non-Ulez-compliant vehicles detected in London on an average day in September 2024 compared with June 2023.
Government data reveals that while London met the air quality standard rules in 2024, other major UK cities like Manchester, Liverpool and Birmingham exceeded them. London is a great example of how a bold policy can lead to positive change, improving the health of millions of people and reducing the burden on the NHS.
5. Microsoft turns to low-carbon steel supplier Stegra for data centre growth
The rapid expansion of data centres is putting climate goals at risk. Their growth is driving up demand for energy, water and steel. Traditional steel production, which relies on coal-based methods, is a major climate problem – the iron and steel sector is responsible for around 8% of global greenhouse gas emissions.
Microsoft have announced a partnership with Swedish company Stegra, a frontrunner in EU green steel production, to supply steel produced with up to 95% fewer emissions than conventional methods for its data centre construction. Instead of relying on traditional coal-based methods, Stegra's plant – set to be completed in late 2026 – will produce steel using green hydrogen.
As AI infrastructure scales up, so too will the demand for steel used in data-centre construction. By sourcing low-carbon steel, Microsoft can reduce embodied carbon and scope 3 emissions in its supply chain.
The deal also sends a market signal. When major tech companies commit to green steel, they help create the demand needed to scale production and potentially lower costs for other industries.
Since slowing data centre growth appears unlikely, ensuring this expansion relies on renewable energy and low-carbon materials will be crucial. New regulations are slowly beginning to emerge to address the industry's climate impact. While one partnership doesn't solve the sector's emissions challenge, Microsoft's deal shows that lower-carbon alternatives are viable options.
What positive climate stories have lifted your spirits this month? Share it with us on X, Bluesky or LinkedIn and we’ll help to spread the word.
