Marine protected areas mitigate the effects of global warming

These are delimited areas at sea. They have no internationally recognized definition but the main objective is the conservation of biodiversity.

The international community is committed to achieving 30% marine protected areas by 2030… Their ecological benefits are fairly well documented…. so we know that it works well to preserve biodiversity. On the other hand, we did not know until now what their overall effects were. And since this solution is often brandished to mitigate the effects of the future climate, it had to be studied.

But the data is very sparse. So these researchers did a meta-analysis, an analysis of the 22,000 studies available on marine protected areas… encompassing any mechanism allowing mitigation and adaptation to climate change. This is the first time that they have been produced globally.

As a result, marine protected areas make it possible to fight against most of the effects of climate documented by the scientific literature, but only when the level of protection of these marine areas is very high…

Interview with Joachim Claudet, CNRS research director at CRIOBE and main author of the study.

Life expectancy plummets since start of COVID-19 pandemic

This is the most serious excess mortality crisis that Western Europe has known since the Second World War. Life expectancy was rising steadily around the world. This study shows that COVID-19 has brought it down in 29 countries.

It shows that in France, life expectancy has decreased by just over 6 months between 2019 and 2020 and has increased by 5, between 2020 and 2021. In two years, life expectancy has declined by 1 ,2 months. It’s almost a return to normal for us.

But while some Western countries have returned to their pre-pandemic levels, this is not the case for everyone. In the United States, for example, life expectancy has fallen by 28 months, a little over 2 years. The strongest are distributed in Eastern Europe. In Bulgaria, life expectancy has dropped from 43 months to over 3.5 years.

The study also points out that the countries with the highest vaccination rates have the best data for life expectancy. But according to the authors, a lower acceptance of vaccination does not on its own explain this divide between western and eastern Europe according to the authors. The only European country to surpass its life expectancy after two years of rising pandemic is Norway, with nearly two more months.

China announces that it has successfully tested the Vactrain, a magnetic levitation train

This is called a Maglev train. It is based on the same principle as the Hyperloop project, proposed by Elon Musk in 2013. In theory, these trains could run at supersonic speeds, around 1500 km/h. For this, the train is not in contact with the rails, it is in magnetic levitation, which makes it possible to eliminate the resistance to friction. But this technology adds to the Hyperloop project a partial vacuum tube, in which the train moves. This removes air resistance, and theoretically achieves higher speed.

During the test, the train would have reached the speed of 129 km/h over a distance of about two kilometers. We are still far from 1500 km/h but according to the team, this is the first successful demonstration.




58 minutes

Tunas use sharks to scratch themselves

This is an amazing observation made by Australian researchers. The initial objective of this study is to study the interactions between fish and sharks in the open sea. For this, they deployed more than 6000 cameras, in 36 different regions in the Indian Pacific and Atlantic oceans. With each time 2 to 3 hours of sequences. And they demonstrate that large fish, such as yellowfin tuna or bluefin tuna, prefer to rub shoulders with sharks rather than members of their own species.

Among the sharks most likely to be scraped by fish are blue sharks. The authors explain that shark skin is smooth in one direction and very rough in the other. So by rubbing from the back of the tail to the head of the animal, the tuna can get rid of the harmful parasites that cling to its skin.




58 minutes

Thanks to Joachim Claudet for his valuable explanations

To go longer

The study on marine protected areas (One Earth, in English)

Marine protected areas combat the effects of climate change (CNRS)

The study on the impact of the COVID-19 pandemic on life expectancy (Nature Human Behavior)

In Europe, the Covid-19 has led to an unprecedented drop in life expectancy for seventy years (The world)

The announcement of the success of the Maglev train test (China Daily, in English)

China successfully tests magnetic levitation train in vacuum tube (Trust my science)

The study on tunas that rub shoulders with sharks (Plos One, in English)

Tunas use sharks to scratch their backs despite the risk of being eaten (New Scientist)

Leave a Comment