PCMcGarry asks: Given the facts that we live on a collection of islands and that tides are predictable, what serious efforts have been made to harness sea power and with what success?
Damian:
The UK is actually home to the world’s most powerful tidal stream turbine, operated by Orbital Marine Power, off Orkney and, the company says now moving into commercial deployment. But the device produces 2MW of power, the same as a small wind turbine. So there is a huge scale up needed to make a difference, and putting electric equipment in moving salty water is tough.
There are big tidal plants in France, South Korea and China, but a large tidal lagoon project for Swansea a decade ago was cancelled by ministers in 2018 who said it was too expensive compared with alternatives such as offshore wind farms and nuclear power.
The climate crisis is causing winter rainfall in the UK to increase, as the Met Office states:
“The winter half-year (October to March) for the most recent decade, 2016–2025, has been 3% wetter than 1991–2020, and 13% wetter than 1961–1990.”
Australia’s Great Barrier Reef is a true natural wonder: a unique and diverse underwater seascape the size of a small country.
However, cycles of disturbance and recovery threaten to turn its colourful coral gardens into algal-dominated seascapes – then back again. And these cycles are becoming more volatile as our world warms.
At the Australian Institute of Marine Science, we’ve been documenting these changes for the past four decades through our Long-Term Monitoring Program. This is one of the longest records of continuous coral reef data in the world.
Concerningly, we’ve watched the health of the Great Barrier Reef begin to fluctuate dramatically over the past 15 years. The 2024 mass coral bleaching – where a record-breaking marine heatwave bleached coral reefs from the Caribbean to the Indian and Pacific Oceans – was particularly destructive. It caused the largest single-year decline in coral ever measured in two regions.
However, our latest report reveals some promising signs of recovery.
However, our latest survey data shows the 2025 bleaching was smaller and less severe than in 2024. This means substantially less coral died, showing not all periods of bleaching have the same outcome. A heatwave’s intensity and duration determines whether corals die or survive. If corals get relief from the heat, they can regain their symbiotic algae and survive.
On the Great Barrier Reef, sea surface temperatures generally peak between January and March. During these summer months, marine heatwaves can increase the risk of coral bleaching. Marine heatwaves occur if ocean temperatures remain unusually warm for the location and time of year for at least five consecutive days.
In spring 2025, a marine heatwave swept across the reef, raising ocean temperatures by up to 1.5°C. According to the Bureau of Meteorology’s climate trends, December 2025 was the reef’s hottest December on record since 1900. If the heatwave continued through summer, the unrelenting heat would have likely led to widespread coral bleaching.
Last year, we recorded the largest single-year decline in living coral cover in four decades of monitoring. This followed the devastating 2024 mass coral bleaching. Coral cover refers to how much of the reef surface is covered in live hard coral, compared with algae, sand and other organisms. It’s one indicator of how healthy a reef is.
In good news, our latest report suggests coral cover increased slightly in some parts of the reef from 2025 to 2026. In the northern region (Cape York to Cooktown), coral cover rose from 30% to 35.1%. This figure increased from 28.6% to 31.6% in the central region (Cooktown to Proserpine). This puts both regions above the long-term average of coral cover. However, coral cover in the reef’s southern region (Proserpine to Gladstone) remained below the long-term average, decreasing slightly from 26.9% to 26.4%.
In early 2026, we noticed signs of regional coral bleaching in the northern and central Great Barrier Reef. But a monsoon soon arrived, bringing widespread cloud and rainy weather, helping to cool the reef at just the right time.
Australian monsoon activity typically coincides with the northern wet season, from October to April. During an active monsoon, clouds, rain and winds help cool the surface of the ocean. Breaking waves and turbulence then mix hotter surface waters with deeper, cooler waters. The monsoon season also reverses winds over the tropics, so northern Australian winds blow as moist northwesterly winds.
Our ability to assess threats to the Great Barrier Reef has vastly improved in the past decade. Global forecast systems can now predict ocean temperatures weeks to months in advance, providing early warnings of marine heatwaves and coral bleaching risks around Australia.
But the reef faces many urgent and increasing pressures.
Crown-of-thorns starfish are one well documented threat to the reef’s corals. Since the 1960s, there have been four waves of crown-of-thorns outbreaks, with a fifth wave currently emerging in the far north. And these coral-eating starfish will move further south in the coming years.
The reef was also hit by two tropical cyclones – Koji and Narelle – between January and March 2026. Cyclones have some cooling effect, but may whip up enormous waves that destroy coral in their path.
The Great Barrier Reef has again shown its remarkable ability to recover. But we can’t take this for granted. Instead, we must urgently act to reduce our carbon emissions and minimise climate change. Developing science interventions offers a pathway to build the reef’s resilience and help it survive a warming future. And we must protect our marine parks to ensure the reef not only survives, but thrives.
The predatory crown-of-thorns starfish feeds on coral.AIMS/LTMP, CC BY-NC-ND
Jessica Benthuysen works for the Australian Institute of Marine Science, a publicly funded research organisation that receives funding from the Australian government, state government departments, foundations and private industry.
Daniela Ceccarelli works for the Australian Institute of Marine Science, a publicly funded research organisation that receives funding from the Australian government, state government departments, foundations and private industry.
Mike Emslie works for the Australian Institute of Marine Science, a publicly funded research organisation that receives funding from the Australian government, state government departments, foundations and private industry.
A wildfire burns near wind turbines in rural Spain. vicvaz/Getty
Intense heat, unprecedented wildfires and savage droughts have hit Europe hard this northern summer. More than 25,000 people have died from the heat, while hundreds of thousands have been evacuated.
Farmers in the United Kingdom have warned of possible shortages of some foods if the drought continues. The Rhine River has fallen to record low levels, disrupting one of Europe’s most important trade and freight arteries.
Climate change made this angry summer vastly more likely. As governments are realising, climate change is no longer just an environmental issue, but a significant challenge for economies, infrastructure and geopolitics.
In the past few years, climate action has dropped down the international agenda. Pro-fossil-fuel governments have pushed back against already-inadequate efforts on climate action. Media coverage is falling, even as climate damage increases.
But will these recent, palpable forms of damage make climate action a priority again?
The corn harvest in France is tipped to fall 35% this year, due to intense heatwaves and drought.Anadolu/Getty
European policymakers have long taken the lead to drive climate action. Many European countries were among the high-ambition nations that helped secure the hard-won Paris Agreement of 2015, with a goal of holding climate change to 1.5°C.
In the 11 years since Paris, progress has been made on electric vehicles and very rapid uptake of solar. Emissions have slowed but not yet begun to fall. Climate change has slipped down the agenda. One estimate counts the reversal of 45 climate policies across 15 jurisdictions in the year to July. The legislated 1.5°C limit is not going to be met.
In Europe, the climate change agenda has been overshadowed by war and instability, trade tensions, economic pressures and the rise of populist parties critical of existing climate policies.
Yet the picture is far from uniform. Public concern about climate change remains high across much of the continent, and this summer has increased its visibility. In Sweden, for example, climate change is a polarising but prominent issue ahead of the upcoming national election.
The problem is, worsening climate damage can amplify concern but divert resources away from the long-term investments needed to reduce greenhouse gas emissions and boost adaptation and preparedness.
This perverse feedback loop is known as derailment risk. The only way to escape this downward spiral is to work now to cut emissions, boost resilience and blunt the effects of climate disruptions.
Climate change also exposes weaknesses in how governments manage risk. Prevention and resilience are often underfunded because benefits are widely shared and may not be realised for years, while costs are typically paid upfront. Responsibility is often split across agencies and levels of government, which creates a bias towards responding to disasters after they happen rather than investing to reduce future losses.
Authorities will need to fund quick-response disaster recovery efforts that both reduce long-term risks and improve response capacity, such as nature-based solutions or rebuilding destroyed houses and infrastructure better or in different locations after disasters.
Surprisingly, natural disasters and climate change have long been discussed in quite separate policy worlds. Last year, a United Nations report found a lack of policy coherence between disaster risk management and climate change adaptation in Europe.
For example, many European insurance policies only fund “like for like” replacement after disaster, limiting people’s ability to rebuild a destroyed house as a stronger, better version. Increasingly, frequent disasters are pushing the insurance industry business model to its limits.
Climate change poses threats to many interconnected systems on which we rely, from farming to roads to electricity grids to glacier-fed rivers. Worse, these threats can interact and compound. Low river levels have made it much harder to cool nuclear reactors in Hungary and Romania, raising the risk of power outages and fuelling tensions between the nations.
Compounding threats can quickly trigger economic disruption, political tension and institutional strain.
Low water levels in the Danube have forced Hungary’s Paks nuclear plant to run at 25% of capacity.Anadolu/Getty
What does this mean for Australia?
Australia has long looked to Europe for policy guidance and leadership on climate change.
But if Europe is focused on responding to disasters rather than climate action, it could hamper already ailing global climate policy efforts. The Trump administration in the United States wants to keep selling gas, coal and oil. While China has emerged as the single biggest force in electrification and clean energy, it has yet to lead on climate.
At COP31, the next global climate talks in Turkey in November, Australia will take on a hard-won diplomatic role to try to get climate action back on track.
Can we respond to disaster – and get serious on climate change?
As Europe grapples with this summer’s damage, we can expect to see concern about climate change increase.
Authorities can only devote so much time, money and attention to problems. There’s now a real risk that intensifying immediate disasters will make it harder to tackle the underlying problem – even if citizens demand renewed action.
But if we don’t get serious in bringing down emissions and reducing our vulnerability to climatic hazards, the next disasters will only be worse.
Lauren Rickards receives funding from the Australian Research Council and Australian Climate Service. She is the co-chair of not-for-profit organisation Climate Change Exchange.
Hartmut Fünfgeld has received funding from the German Federal Ministry of Research, Technology and Space, the German Federal Ministry for the Environment, Climate Action, Nature Conservation and Nuclear Safety, and the German Research Foundation.
Magnus Moglia has in the last five years received funding from the iMOVE CRC, Yarra Valley Water, Sydney Water, Australian Climate Services, Victoria's Sustainability Victoria, the City of Boroondara, ACIAR and AHURI. He is on the not-for-profit Regen Melbourne's research council and is a committee member for the Macedon Ranges Sustainability Group.
Videos posted on social media have Brisbane residents heading out to get a glimpse of neon-blue bioluminescence. But what causes it, and is finding it more than blind luck?
