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Climate action

A blue river carves a channel through ice covered in brown mud.

Brown sediment marks rapidly melting ice on the Greenland ice sheet.Credit: Martin Zwick/Reda&Co/Universal Images Group via Getty

Brown sediment marks rapidly melting ice on the Greenland ice sheet. Even at present levels of warming, the ice sheets in Greenland and Antarctica are at risk of irreversible collapse that could boost sea levels this century and beyond.

News

How to stave off climate ‘tipping points’

Climate change has placed the world in danger of breaching numerous planetary ‘tipping points’, according to a scientific assessment compiled by more than 200 scientists. Crossing those points could lead to irreversible effects on natural systems that are crucial to human livelihoods. For example, large parts of the Amazon rainforest could be replaced by savannah with as little as 2 °C of warming. “These tipping points pose threats of a magnitude that has never been faced before by humanity,” says climate scientist Tim Lenton, who led the report. The report also points to ‘positive tipping points’ — some of which, such as a shift to solar and wind power, are already in progress — that could result in runaway benefits for the climate.

Some scientists remain wary of overemphasizing tipping points, because it’s difficult to define the risks and assess their likelihood. But few researchers doubt that the risks are real — and that we must accelerate efforts to prevent them.

Nature | 4 min read

Reference: Global Tipping Points report

News

Scientists bring climate protests home

Scientist Rebellion, an international group of researchers that uses civil disobedience to prompt climate action, has organized protests across 23 countries during the 2-week COP28 meeting in the United Arab Emirates (UAE) — rather than demonstrate at the event itself. Participants told Nature that they feel disillusioned with the progress from past COPs and the fact that this year’s event is being hosted by a major fossil-fuel producer. They also want to avoid the carbon emissions required to get to Dubai and the risks that come with the UAE’s strict laws limiting protest and free speech. In an open letter, Scientist Rebellion urged scientists and academics to join them. “We need you,” says the letter. “Wherever you are, become a climate advocate or activist.”

Nature | 6 min read

Opinion

Climate science needs communicators

When wildfires engulfed California in 2020, climate scientist Daniel Swain put his research on hold to answer journalists’ questions and speak to the public about the science behind the disaster. Many others with relevant expertise would do the same, he says, but a lack of tangible support from institutions is holding them back. “Climate scientists are ready and waiting to meet the communication and engagement challenges that the coming years will bring,” he writes. “Forward-thinking institutions and funders must urgently find the means to support them.”

Nature | 5 min read

Opinion

Combat greenwashing with better science

“The planet cannot afford delays, excuses, or more greenwashing,” writes climate leader Catherine McKenna in a United Nations report on how to hold ‘non-state actors’ — industry, financial institutions, cities and regions — to account on their net-zero promises. Researchers need to rise to this challenge by scrutinizing disclosures, targets and metrics for progress, and advising on what they should look like, argues a Nature editorial.

Nature | 6 min read

Reference: United Nations report

Brain implants help after severe head injury

Brain implants that activate and restore connections between damaged neurons have improved cognition in people with traumatic brain injuries. The five participants in a small clinical trial had a 15–52% improvement in their processing speed in a cognitive test after three months. The implants send an electrical current to parts of the brain involved in attention, decision-making and working memory. “For some participants, the improvements have been transformative, even many years after the injury,” says neurosurgeon Jaimie Henderson.

Nature | 4 min read

Reference: Nature Medicine paper

Model predicts when sea life will get tangled

Researchers have developed a way to forecast when whales and turtles are likely to get entangled in fishing gear — almost a year in advance. The model uses widely available, low-resolution, global forecasts of sea surface temperature to accurately predict water temperatures that draw the animals to certain areas. The method could give fishers plenty of warning of the need to pause their work, moderating the impact on their livelihoods and saving more animals.

Nature | 4 min read

Reference: Nature Communications paper

Features & opinion

A painting made more than 43,000 years ago shows an anoa, or dwarf buffalo.

A painting made more than 43,000 years ago shows an anoa, or dwarf buffalo.Credit: Ulet Ifansasti for Nature

Scientists race to save ancient cave paintings

Some of the oldest pictures in the world were drawn more than 45,000 years ago in caves on the southwestern peninsula of Sulawesi in Indonesia. Despite having lasted so long, they’re now disappearing as the surface of the cave walls is peeling off from the white limestone underneath. No one knows exactly why, but researchers point to pollution, climate change, human exhalations and the dust and vibrations produced by mining as possible causes. Scientists are scrambling to solve the mystery before the paintings are lost for good.

Nature | 14 min read

Ill-informed AI use fuels irreproducibility

The naive use of artificial intelligence (AI) is driving a deluge of unreliable, useless or wrong research. This has happened, for example, when researchers report that algorithms can reliably classify images or even diagnose diseases, but fail to realize that their systems are really only regurgitating artefacts in the training data. “AI provides a tool that allows researchers to ‘play’ with the data and parameters until the results are aligned with the expectations,” says computer scientist Lior Shamir. There are checklists that can help scientists to avoid common problems, such as insufficient separation between training and test data. Many argue that the way forward is to make all code and data available for public scrutiny.

Nature | 14 min read

Quote of the day

“Done right, grant writing can reconnect you with the joy that led you to become a scientist in the first place.”

By reframing grant writing as a way to rediscover your purpose, practise your writing and build community, the ‘necessary evil’ can actually become fun and fulfilling, say trainers Courtney Peña, Amber Moore and Crystal Botham. (Nature | 5 min read)