It has already prompted the government to reform New Zealand’s climate laws to prevent companies being sued for damages caused to the climate by their emissions.
The government’s reasoning is that climate policy should be decided by elected officials and existing laws, not by the courts, to ensure “legal clarity and certainty” for businesses around their obligations.
Now the dispute has taken another turn. Smith has filed fresh proceedings in the High Court, asking for a declaration that the government’s decision to introduce the law change – and the process behind it – were unlawful.
There are many interesting aspects of these cases that legal observers will be following closely. Among them is whether New Zealand’s proposed law change is consistent with the international climate commitments it recently endorsed.
A landmark case
Smith alleges the companies he is suing have materially contributed to the climate crisis through their greenhouse gas emissions. He also argues their actions have caused harm to his whenua and moana, including places of cultural, spiritual and historical significance to him and his wh?nau.
In 2020, the companies asked the courts to strike out Smith’s case before it reached trial. The applications worked their way through the courts before the Supreme Court heard the final appeal in 2022.
In a landmark unanimous decision in 2024, the Supreme Court ruled that while Smith’s claims – including public nuisance, negligence and a novel tort of “climate system damage” – were legally novel, they raised arguable questions that deserved to be tested at trial rather than dismissed at an early stage.
The court ordered the case be reinstated in full and proceed to the High Court, where it is currently scheduled for trial in April 2027.
If the government’s amendment becomes law, however, it will bring an end to that trial before it begins – and block any future lawsuits against corporate emitters.
That is relevant not just for Smith’s case, but for New Zealand’s wider climate obligations.
In 2021, Vanuatu announced at the United Nations that it would seek an advisory opinion from the International Court of Justice on states’ legal obligations in relation to climate change. New Zealand was among the countries that supported the move.
The resulting UN resolution was adopted by consensus in 2023. The International Court of Justice delivered its advisory opinion in 2025, unanimously finding that states have obligations to protect the climate system and that there may be legal consequences if they fail to do so.
Advisory opinions are not legally binding in the same way as judgements in contested cases. But opinions from the International Court of Justice are highly authoritative and are often cited by courts and tribunals around the world.
One important aspect of the court’s opinion concerned private actors. The court said states may be responsible if they fail to take necessary regulatory and legislative measures to limit emissions caused by private entities within their jurisdiction.
Seen in that light, removing an individual’s ability to sue companies over climate damage could be seen as weakening one possible “check and balance” on emissions caused by private actors.
A gap between words and action
The timing of the recent developments is also notable. Only eight days after announcing the proposed law change in May, New Zealand voted with 140 other countries at the UN to endorse the International Court of Justice’s advisory opinion on climate change.
New Zealand’s parliament also declared a climate emergency in 2020. Yet domestically, the government is proposing to close off a legal pathway through which major emitters could be held accountable for climate-related harm.
This does not mean every climate case against a company must succeed. That is for the courts to decide on the evidence and the law. But preventing such cases from being heard at all raises a different concern.
It risks placing New Zealand’s domestic climate policy out of step with the international climate principles it has supported.
Climate change is one of the defining challenges of this century. The science is clear that limiting global warming requires rapid and deep reductions in greenhouse gas emissions across all sectors this decade.
The proposed amendment is therefore about more than one lawsuit.
It raises fundamental questions about whether New Zealand’s laws will match the commitments it makes internationally – and whether future generations will inherit climate policies that reflect accountability, or merely efforts to avoid it.
Justin Sobion does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
Office for Environmental Protection finds failures by department when it granted emergency authorisation in 2023 and 2024
The UK government breached environmental law on several occasions when granting farmers permission to use a bee-killing pesticide, a watchdog has found.
In 2023 and 2024, the Department for Environment, Food and Rural Affairs (Defra) in the then Conservative government granted emergency authorisation to allow farmers to use a banned neonicotinoid pesticide on sugar beet crops.
A “prolonged, dangerous heatwave” is expected to intensify across parts of the central and eastern United States over the next few days and into the holiday weekend, bringing record-breaking temperatures, humidity and dangerous conditions to millions of Americans.
The National Weather Service (NWS) warned on Thursday that temperatures between 95F (35C) and 105F (40.5C), combined with high humidity, will push heat index values across parts of the region to between 100F and 115F.
Temperatures could reach 44C in south-east Spain as fights break out in Paris supermarkets over air-conditioning units
Spain and France are bracing for another possible heatwave that could bring temperatures of 44C (111F) over the coming days, as figures show that June’s extreme heat was responsible for more than 2,000 excess deaths in the two countries.
Spain’s state meteorological agency, Aemet, said a mass of dry and very hot air would bring persistently high temperatures to much of Spain from Saturday, adding that temperatures in parts of the south-east could hit 42C to 44C on Tuesday.
The world’s oceans are the hottest on record for June, pushing past records set during the 2023–24 El Niño years.
Right now, the average sea surface temperature is just under 21°C across the world’s tropical and temperate oceans. Before widespread industrialisation in 1870, the temperature was about 19.6°C.
That may not sound like a big difference. But heating the world’s oceans this much requires a truly enormous amount of energy. Of all the extra heat trapped by greenhouse gases from burning coal, gas and oil, more than 90% has gone into the world’s oceans.
As a result, the oceans are getting rapidly warmer. In 2025, the heat added was the equivalent of about 12 Hiroshima-scale nuclear bombs exploding every second of every day.
To find a climate analogue comparable to what’s happening now in the oceans, we would have to go back around 120,000 years to before the last ice age. Back then, slow shifts in Earth’s orbit led it to heat up gradually over thousands of years. Humans have accomplished a similar result in a little over a century.
But the heat in the ocean doesn’t just stay there. Hotter oceans fuel stronger cyclones, a more humid atmosphere, more intense rainfall and more heat in air masses over the seas, which can in turn make heatwaves over land more likely and more intense.
The El Niño forming in the tropical Pacific right now is likely to be a big one. As it develops, we can expect to see warmer temperatures and extreme events such as marine heatwaves in the western Indian, tropical Atlantic and eastern Pacific Oceans.
Global ocean sea surface temperatures are at the highest level recorded during June.HadISST, CC BY-NC-ND
Where are the hotspots on land and in the ocean?
Europe is sweltering through a record-breaking heatwave. The oceans surrounding the region and in enclosed seas are also exceptionally hot.
Parts of the Mediterranean are up to 6°C hotter than the long-term average.
The forming El Niño has led to sea surface temperatures about 1.24°C warmer than average across a large area of the central eastern Pacific.
There’s much more heat below the surface as well. Subsurface conditions in the eastern Pacific are more than 6°C above average.
A typical El Niño lasts about a year. The full effect on atmospheric heat becomes clearest towards the end of the cycle. That means while we can expect 2026 to be very hot – perhaps a new record – next year is very likely to be even hotter, as ocean heat is moved back to the surface. We saw this during El Niño events over 2023–24 and 2015–16.
Steady ocean warming coupled with longer-lasting and more intense marine heatwaves pose huge threats to marine ecosystems such as coral reefs, sea grass meadows and coastal reefs. Research on the 2023–24 El Niño and the warm 2024 year showed widespread impacts.
Regions such as the eastern Pacific and the Mediterranean are unusually hot at present. This map shows temperature anomalies on June 30th 2026.Climate Reanalyzer, CC BY-NC-ND
In June 2023, a record-breaking marine heatwave broke previous temperature records across the North Atlantic Ocean. Soon afterwards, large areas of Europe were hit by intense heatwaves, while extreme rains triggered deadly floods in Spain and severe bushfires broke out around the Mediterranean.
Rising ocean temperatures have many consequences.
A warmer ocean is less able to cool the land over summer. Warmer oceans also lead to more evaporation, boosting humidity and fuelling more intense and more sudden extreme rain and floods. These can have devastating consequences.
During El Niño events, there’s a clear geographical pattern. The regions we expect to be warmer or cooler during an El Niño roughly reflect where we are more or less likely to get marine heatwaves and more intense tropical cyclones.
Typical cyclone areas such as the western Indian Ocean could see stronger cyclones dumping heavier rainfall when they hit land. El Niño tends to bring extreme rain and floods to the western South America and dry conditions over parts of Australia and Southeast Asia.
Global surface temperatures tend to spike during strong El Nino years (red) and fall back during La Nina years, even as climate change drives the baseline higher.HadCRUT, CC BY-NC-ND
Can we prepare?
We are gaining a better understanding of how big climate drivers like El Niño shape weather and how to use ocean data from around the world to develop better seasonal forecasts authorities can use to prepare.
Over the past two years, we have improved our ability to forecast marine heatwaves three to four months ahead in Australia, the United States and other regions. Forecasts give marine authorities a chance to act early by reducing allowable fishery catches and beginning conservation efforts for vulnerable species.
The world’s oceans have been steadily warming since the 1870s, as this climate stripes visualisation shows. El Niño years (red tag above) tend to boost ocean warming while La Niña years (blue tag below) tend to be cooler. Tag width represents strength of the event.HadISST (before 1982)/NOAA OISST (1982 onward), CC BY-NC-ND
This early success in ocean forecasting may be short-lived. The current US administration last year slashed funding for climate data gathering networks and has worked to dismantle the National Center for Atmospheric Research.
This year, the administration announced it would end funding for a key ocean monitoring network before backing down.
Ongoing collection of ocean data is crucial for ocean and land forecasts. If they are weakened or discontinued, we could face the challenge of dealing with worsening climate impacts blind.
Ending the measuring of climate change won’t stop it happening. The only way to keep climate change from steadily worsening is to reach net zero as soon as humanly possible. Until then, we must use forecasts to prepare for what we can’t avoid.
Matthew England receives funding from the Australian Research Council.
Alex Sen Gupta receives funding from the Australian Research Council.
Alistair Hobday does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
