Veille 2.1

Des trous gigantesques se forment en Turquie en raison des pompages excessifs des nappes souterraines pour l’irrigation. Effondrements, craintes des habitants... Les effets sont nombreux.

Giant ice sheets, ocean currents and permafrost regions may already have passed point of irreversible change

Le plancher océanique de l’Arctique s’est fissuré à une vitesse inquiétante au cours des vingt dernières années. Les scientifiques marins à l’origine de la découverte ont ainsi comparé la profondeur de ces fissures à celle d’une rue de Manhattan composée d’immeubles de six étages, annonçait Live Science le 17 mars.

Temperature rises will top 2.4C by the end of this century, based on the short-term goals countries have set out, according to research published in Glasgow on Tuesday. That would far exceed the 2C upper limit the Paris accord said the world needed to stay “well below”, and the much safer 1.5C limit aimed for at the Cop26 talks.

the sediments below oxygen-depleted waters are a significant source of nitrous oxide (N2O). This gas is released into the atmosphere when deep water rises to the surface in a process known as upwelling. Nitrous oxide, more commonly known as “laughing gas,” is a potent greenhouse gas, 300 times more powerful than carbon dioxide. Global emissions of N2O are increasing as a result of human activities that stimulate its production.