Scientific news in small doses

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

Eric-Pierre Champagne
The Press

Three quarters of tree species at risk in 2050

Three out of four is the proportion of tree species that will be considered at risk in the main cities of the world in 2050, due to climate change. This estimate was made by a team of international researchers whose work was recently published in the journal Nature Climate Change. Their calculations are based on a scenario of moderate greenhouse gas (GHG) emissions, which would lead to a warming of 2.8℃ by the end of the century. The analysis covered 164 cities around the world, in 78 different countries. The study invites decision-makers to carefully choose the tree species most likely to resist a rise in temperature in their planting projects.

Quiz

Could climate change lead to a change in the color of the lakes?

The answer is yes, according to a recent study published in the journal Geophysical Research Letters. According to the authors, about a third of the planet’s lakes have a blue color, but this could well change in the future due to global warming. The color of a lake depends on several factors, including the ambient temperature. In particular, heat allows algae to form more easily and in greater numbers, which influences the color of a body of water. According to their analysis, 3800 lakes could change color by the end of the century.

The number

10%

The torrential rains caused by the hurricane Ian have been increased by 10% due to global warming, estimates a group of American researchers. To reach this conclusion, they used a method that was used in a study published in the journal NatureCommunications last April, the title of which was: Attribution of 2020 hurricane season extreme rainfall to human-induced climate change.

One more argument for climate justice

According to a study published in Nature Sustainability, 1% of the world’s population is responsible for a quarter of the increase in GHG emissions since 1990. It is in North America that we find the largest proportion of the richest, who emit the most GHGs. These figures militate in favor of climate justice advocates, who want richer countries to contribute more to the fight against climate change. Remember that in 2019, 10% of the world’s population was responsible for 48% of GHG emissions into the atmosphere.

Getting hotter in the cities

By 2050, in more than 970 cities around the world, the average summer temperature will exceed 35℃. A situation that will have significant social and economic effects, argues the most recent report from the Adrienne Asht-Rockefeller Foundation Resilience Center. Currently, 354 cities are dealing with average summer temperatures above 35℃. By mid-century, 1.6 billion people will be affected by rising temperatures in many urban centers. According to demographic projections, almost 70% of the world’s population will live in urban areas by 2050.