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Aerial view of the Pantanal wetlands, in Mato Grosso state, Brazil.

Tropical wetlands, such as the Pantanal in Brazil, are a major source of methane emissions.Credit: Carl De Souza/AFP via Getty

Methane is spiking ‘dangerously fast’

As global methane concentrations soar to nearly triple preindustrial levels, some researchers fear that global warming itself is behind the rapid rise. Data released in January by the US National Oceanic and Atmospheric Administration show that atmospheric methane has raced past 1,900 parts per billion. The growth of methane emissions began a rapid and mysterious uptick around 2007. The spike has caused many researchers to worry that global warming is creating a feedback mechanism that will cause ever more methane to be released, making it even harder to rein in rising temperatures. The grim milestone underscores the importance of a pledge made at last year’s COP26 climate summit to curb emissions of the greenhouse gas, which is at least 28 times as potent as CO2.

Nature | 5 min read

First glimpse of an isolated black hole

Astronomers have, for the first time, seen an isolated black hole, wandering unattached across the Milky Way. Lone black holes probably litter the Galaxy, but they’re extremely hard to spot because they are typically observed as they interact with other objects, such as companion stars. Confirming the black hole’s presence took ten years of observations, focusing on how the object’s extreme gravitational pull warps the light from distant stars behind it.

Nature | 5 min read

Reference: arXiv preprint (not peer reviewed)

Climate pledges crumble under scrutiny

Major companies are not living up to the promises they have made to reduce their carbon emissions to zero. An analysis of publicly available corporate documents, such as annual sustainability reports, shows that 25 companies — which together are responsible for about 5% of global emissions — are actually committing to do far less. Of the 25 companies, selected to represent a cross-section of industries, just 3 — the Danish shipping giant Maersk, the UK communications firm Vodafone and the German telecommunications company Deutsche Telekom — have clearly committed to deep decarbonization. Thirteen of the 25 provide detailed plans that would, on average, curb emissions by just 40%, rather than 100%, over the next few decades; the other 12 companies have not provided any details about what exactly they are committing to do.

Nature | 6 min read

Reference: New Climate Institute report

Conspiracy lies close butterfly centre

A butterfly conservation centre near the US–Mexico border has been forced to close after becoming the focus of extreme far-right conspiracy theories. “When I took this job, I thought I would be able to spend a good amount of time outdoors: butterflies, birds, educating children, writing grants,” says Marianna Trevino Wright, who runs the non-profit nature preserve. “Now every day my children literally worry whether I’m going to survive a day at work.”

The New York Times | 9 min read

Features & opinion

How to safeguard from quantum hackers

Future quantum computers could crack the encryption algorithms that underpin our online security. In cybersecurity circles, they call it Q-day — the day when all encrypted communications, including any recorded messages from the past, become vulnerable. Computer scientists have created a crop of quantum-resistant cryptographic algorithms to fend off the danger. Which algorithms will become standard could depend in large part on a decision soon to be announced by the US National Institute of Standards and Technology. “I think it’s something we know how to do; it’s just not clear that we’ll do it in time,” says mathematician Peter Shor.

Nature | 14 min read

Why we need random COVID sampling

One in four SARS-CoV-2 infections in the United States has been reported. Across Africa, the average is closer to one in seven. All this undercounting renders many important questions unanswerable, argues biostatistician Natalie Dean. Random sampling — such as that done fortnightly of around 180,000 people across the United Kingdom — is essential to guide policy and personal decisions, she writes.

Nature | 5 min read

Why wasabi is at risk

After 400 years of cultivation, farmers in Shizuoka, Japan who grow wasabi now face the challenges of global warming, untended forests and a lack of successors. Government estimates suggest that the volume of the nose-tingling plant produced in Shizuoka has declined by close to 55% over the past decade. Researchers and growers have started to experiment with ways of developing wasabi varieties that will thrive even under rising temperature conditions, but there is no guarantee they will taste good or be as popular among consumers.

The New York Times | 7 min read

Where I work

Sergio Rocha inspects rows of cannabis plant seedlings in grow bags inside a greenhouse

Sérgio Rocha is an agronomist engineer and executive director of ADWA Cannabis in Viçosa,Credit: Washington Alves/Reuters/Alamy

Agronomist Sérgio Rocha breeds fast-growing marijuana plants at Viçosa University in Brazil. “The Brazilian congress is considering making cannabis cultivation for medical and industrial purposes fully legal,” he says. “Ultimately, our goal is to create plants that are completely comfortable in Brazilian soil and weather.” (Nature | 3 min read)


“There is an audience out there looking for something beyond the ‘maths is difficult’ narrative.”

Quantum-algebra researcher Angela Tabiri founded Femafricmaths, which shares the stories of African female mathematicians through video interviews posted on social media. (Nature | 4 min read)