The Guardian

Pepper, a nine-month-old sea lion, has mesmerised her carers by performing intricate rhythmic gymnastics-style circles through the waters at Point Defiance zoo and aquarium in Tacoma, Washington. Noelle Tremonti, a biologist at the aquarium, says the strips help the pup learn how to interact with kelp, which grow in abundance in the animal's natural environment, and how to explore her environment using her mouth. Pepper was the first sea lion born at the facility's its 120-year history

• ‘A ribbon dancer’: captive baby sea lion performs acrobatics with artificial kelp

As Scottish energy firms race to meet challenges of storing power, critics fear plans will affect delicate hydrology of loch

Brian Shaw stood at the edge of Loch Ness and pointed to a band of glistening pebbles and damp sand skirting the shore. It seemed as if the tide had gone out.

Overnight, Foyers, a small pumped-storage power station, had recharged itself, drawing up millions of litres of water into a reservoir high up on a hill behind it, ready for release through its turbines to boost the UK’s electricity supply. That led to the surface of Loch Ness, the largest body of freshwater in the UK, falling by 14cm in a matter of hours.

Injecting pollutants into the atmosphere to reflect the sun would be extremely dangerous, but the UK is funding field trials

Some years ago in the pages of the Guardian, we sounded the alarm about the increasing attention being paid to solar geoengineering – a barking mad scheme to cancel global heating by putting pollutants in the atmosphere that dim the sun by reflecting some sunlight back to space.

In one widely touted proposition, fleets of aircraft would continually inject sulphur compounds into the upper atmosphere, simulating the effects of a massive array of volcanoes erupting continuously. In essence, we have broken the climate by releasing gigatonnes of fossil-fuel carbon dioxide, and solar geoengineering proposes to “fix” it by breaking a very different part of the climate system.

Raymond T Pierrehumbert FRS is professor of planetary physics at the University of Oxford. He is an author of the 2015 US National Academy of Sciences report on climate intervention

Michael E Mann ForMemRS is presidential distinguished professor at the University of Pennsylvania. He is the author of Our Fragile Moment: How Lessons from Earth’s Past Can Help Us Survive the Climate Crisis

Campaigners say introduction of feasibility test in England and Wales over bathing status is ‘snub to communities’

Rivers are unlikely to be granted the protections of bathing water status under the government’s changes to the system, campaigners have said.

River activists have reacted with fury as details of the reforms were revealed on Wednesday.

If you don’t believe the scientists, will you believe the insurance companies?

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My homeplace has experienced four natural disasters in eight years. But I’d never seen the like of this bird before, vibrantly green and startlingly beautiful

We were midway through our cyclone preparation when my mother broke her leg. She stepped into her bedroom to retrieve something, tripped and fell, and that was that. My mother is 74 and hardy, so this sudden break took us by surprise. Once I got her home, leg in brace, we’d lost significant time, and my household was down to one functional human: me.

This is the fourth natural disaster I’ve experienced in the last eight years. One-in-100-year floods (2017), unprecedented bushfires (2019), one-in-1,000-year floods (2022) and now Cyclone Alfred. Cyclones are a new threat. I’ve lived in my homeplace, in northern New South Wales, for almost 50 years and we’ve never had a cyclone cross land in our vicinity. We were, as they say, in uncharted waters.

Research shows apex predators are increasing in numbers and excreting important nutrients into Top End waterways

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The growing saltwater crocodile population in the Northern Territory has led to the creatures gorging on nine times more prey than they did 50 years ago, with the apex predators contributing important nutrients to Top End waterways, new research suggests.

Saltwater crocodile populations have increased exponentially in recent decades, from less than 3,000 in 1971, when a ban on hunting was introduced, to more than 100,000 animals today.

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Swings between drought and floods striking from Dallas to Shanghai, while Madrid and Cairo are among cities whose climate has flipped

Climate whiplash is already hitting major cities around the world, bringing deadly swings between extreme wet and dry weather as the climate crisis intensifies, a report has revealed.

Dozens more cities, including Lucknow, Madrid and Riyadh have suffered a climate “flip” in the last 20 years, switching from dry to wet extremes, or vice versa. The report analysed the 100 most populous cities, plus 12 selected ones, and found that 95% of them showed a distinct trend towards wetter or drier weather.

Applications to the sustainable farming initiative no longer accepted but no clarity on what will replace it and when

Farming and countryside groups in England are furious that the government has paused a key post-Brexit farming payments scheme with little information about what will replace it and when.

In a statement on Tuesday evening the Department for Environment, Food and Rural Affairs (Defra) said the sustainable farming incentive would no longer accept new applications.

RFK Jr’s ‘Maha’ giving fresh momentum to longtime efforts to outlaw additives, which is now a bipartisan movement

At least a dozen US states – from traditionally conservative Oklahoma to liberal-leaning New York – are rushing to pass laws outlawing commonly used dyes and other chemical additives in foods, citing a need to protect public health.

In one of the most far-reaching efforts, West Virginia last week advanced a sweeping ban on a range of common food dyes that have been linked to health problems, particularly for children, with overwhelming support from both Republicans and Democrats.

Tiny bits of plastic can end up in water and soil at alarming levels, said lead author of University of Missouri paper

Fertilizers that shed microplastics are increasingly spreading on America’s cropland, research shows, raising new worry about the soil contamination and safety of the US food supply.

A peer-reviewed University of Missouri paper found common types of controlled-release fertilizers are often encapsulated with plastic and can be so small that they could be considered microplastics. Those are designed to break down into even smaller pieces of plastic once spread in fields.

Staff crisis at Environment Agency, which helps monitor 950 sites, means it is hearing about incidents later than normal, insider says

The team responsible for preventing environmental risks at England’s most hazardous industrial sites is facing a recruitment crisis and one insider has warned environmental incidents are going unchecked.

The control of major accident hazards (Comah) regulations cover 950 of England’s most hazardous industrial sites – from nuclear power plants to chemical manufacturers – in locations such as Buncefield oil depot near Hemel Hempstead, where, in 2005, the largest explosion in peacetime took place in the UK.

Migratory insects covered 4.2 acres in Mexican forests this winter but number remains far below long-term average

The population of eastern monarch butterflies – who migrate from Canada and the US to Mexico during the winter – has nearly doubled over the last year, according to a recent report commissioned in Mexico, generating optimism among nature preservationists.

The modest growth in numbers for the orange-and-black butterflies follows years of ongoing conservation efforts – and perhaps provides a sliver of optimism after otherwise discouraging long-term trends for the species.

Steven Payne, 37, was fatally attacked at remote beach in Western Australia while on a six-month holiday with his partner and dog

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A surfer fatally mauled by a shark at a remote beach in Western Australia was on a six-month holiday with his partner and pet dog.

Steven Payne, 37, was attacked on Monday at Wharton Beach, east of Esperance, and his remains are yet to be recovered, police have said.

US-style mega-farms in Herefordshire face tough new regulations after high court ruling

Industrial poultry farms face tough new regulations around the disposal of chicken manure after a judge ruled it can be classified as waste and requires a detailed and transparent plan to dispose of it without damaging the environment.

The high court ruling means new US-style mega-farms in Herefordshire will have to deal with poultry manure as if it was industrial waste.

Tetrodotoxin immobilises the female – who is about two to five times bigger than the male – so mating can occur, researchers observed

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Male blue-lined octopuses inject females with venom during sex, paralysing their larger mates to avoid being eaten, new research has found.

The blue-lined octopus is a tiny, highly dangerous cephalopod found commonly in shallow reefs and tide pools.

Annual survey by IQAir based on toxic PM2.5 particles reveals some progress in pollution levels in India and China

Nearly every country on Earth has dirtier air than doctors recommend breathing, a report has found.

Only seven countries met the World Health Organization’s guidelines for tiny toxic particles known as PM2.5 last year, according to analysis from the Swiss air quality technology company IQAir.

'There's good news when it comes to the rivers in the northern rivers – all are receding,’ the New South Wales premier says, adding: ‘The immediate threat to the community has been reduced.' State Emergency Service deputy commissioner Damien Johnston says overnight rainfall was not significant enough to affect river systems but warns residents: ‘You do need to be vigilant’

• Hell and high water: flooded-in northern rivers residents grapple with ‘no water, no phone or power’

• Squatters in flood buyback homes to be evicted and properties demolished, NSW premier says

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Alfred is being used as the latest front in an ideological war, but facts are relevant to how we prepare for a climate-changed future

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It’s not a good time for climate science. The Trump administration has sacked more than a thousand staff from the US National Oceanic and Atmospheric Administration, the country’s leading agency for weather forecasting and climate science, potentially damaging its ability to do lifesaving work forecasting hurricanes and other extreme weather events. The New York Times reported plans are under way to fire another 1,000. If true, that will take the cuts to about 20% of the workforce.

On Monday, it was announced Nasa was axing its chief scientist, Katherine Calvin, who had been appointed to lead the agency’s work on climate change. In trademark Donald Trump/Elon Musk style, there appears little care or sense in where cuts have been made. It’s destruction for destruction’s sake, with tens of thousands of peer-reviewed scientific papers underpinning the understanding of climate science dismissed as a “hoax” or, somehow, “woke”. As in most areas, what happens in the US on forecasting and science capability will have an impact beyond its borders.

Researchers say problem could increase number of people at risk of starvation by 400m in next two decades

The pollution of the planet by microplastics is significantly cutting food supplies by damaging the ability of plants to photosynthesise, according to a new assessment.

The analysis estimates that between 4% and 14% of the world’s staple crops of wheat, rice and maize is being lost due to the pervasive particles. It could get even worse, the scientists said, as more microplastics pour into the environment.