Scientific news in small doses

A few milligrams of all the scientific news of the week.

Eric-Pierre Champagne
The Press

4 billion people and 29 ^ohVS

By the end of the century, 40% of the world’s population could live in a climate where the average annual temperature is above 29 ^ohC. This is the conclusion of a study conducted by researchers at the University of Exeter, UK, which has just been published on the bioRxiv dissemination platform. Thus, in a scenario of global warming of 2.7 ^ohC by 2100, up to 4 billion people should become accustomed to living with such daily temperatures. The most affected countries would include India, Nigeria and Indonesia. In the increasingly unlikely event that the world succeeds in limiting warming to 1.5 ^ohC, this sad record could be halved.

Quiz

According to a recent report, what is the best investment to reduce global greenhouse gas (GHG) emissions?

According to the firm Boston Consulting Group (BCG), investments in alternatives to meat and dairy products are by far the most profitable in terms of greenhouse gas (GHG) reduction. In a recently released report, BCG indicates that these investments make it possible to generate three times less GHG than the sums devoted to “green cement” technologies, seven times less than those in “green buildings” and eleven times less than those in zero-emission vehicles.

The number

8000

Scientists estimate the current population of fin whales in Antarctica at around 8,000 individuals. Good news for the second species of whale in terms of size, after the blue whale. The adult fin whale is on average 22 m long and weighs 70 tons. Balaenoptera physalis what had seen its population in Antarctica decline rapidly during the 20th^e century, due to hunting, which was banned from 1976. In 2018 and 2019, scientists from the University of Hamburg, Germany, flew the equivalent of 3251 km above Antarctica . In particular, they were able to observe more than 100 groups of whales, comprising 1 to 4 individuals, as well as 8 groups of approximately 150 individuals. The results were published in the journal Scientific Reports.

Plant trees or not

Is planting trees on former agricultural land the best option for capturing carbon? Not necessarily, at least not according to a team of Quebec researchers who took an interest in the question. Their work made it possible to measure the amount of carbon fixed in plants and in the soil of 26 lands left fallow and 23 other lands that had been reforested with white spruce. Over a period of 50 years, the amount of CO₂ captured by the two courses in Abitibi was comparable. One explanation is that when land is allowed to regenerate naturally, a greater diversity of trees, including hardwoods, takes place. Hardwoods capture more carbon than conifers. The Quebec study was published in the journal Plant and Soil.

Expensive shows

Between 1990 and 2014, greenhouse gas (GHG) emissions from the United States resulted in losses totaling US$1.8 trillion for the rest of the world. This is the conclusion of a study conducted by researchers at Dartmouth College, New Hampshire. For the same period, China’s emissions resulted in similar losses, while Russia, India and Brazil cost other nations US$500 billion. Unsurprisingly, it is the least developed countries in the south that have suffered the most from emissions from industrialized countries. The study collected data from 143 countries.