Les articles sur Internet ont tendance a dispaitre avec le temps, et on perd donc souvent des textes importants comme référence, alors j’ai recopié cec texte de Freeman Dyson, un des plus grands scientifiques de notre ère, le successeur de Einstein selon plusieurs.
Texte de Freeman Dyson Décembre 2015
Misunderstandings, questionable beliefs mar Paris climate talks
Representatives from 196 countries are in Paris to negotiate an agreement about climate change, specifically a reduction in greenhouse gas emissions. But the basic beliefs of the UN’s Intergovernmental Panel on Climate Change, which is organizing the talks, are questionable, and any binding agreement would likely do more harm than good.
The IPCC believes climate change is harmful; that the science of climate change is settled and understood; that climate change is largely due to human activities, particularly the release of carbon dioxide into the atmosphere by industrial societies; and that there is an urgent need to fight climate change by reducing the emissions of carbon dioxide.
The most questionable of these beliefs is the notion that the science of climate change is settled and understood. The biggest of all climate changes have been the ice ages, which have covered half of North America and Europe with kilometer-thick sheets of ice. Ice ages happened repeatedly in the past, and we are about due for another one to start. A new ice age would be a disaster far greater than anything we have to fear from climate warming. There are many theories of ice ages, but no real understanding. So long as we do not understand ice ages, we do not understand climate change
Another important thing that we do not understand is the possible effect of the sun on climate. The sun’s magnetic activity is strongly variable, and it appears to be correlated with the earth’s climate. When the sun is magnetically active, climate gets warmer. We do not know how much of the warming is caused by the sun. If the effect of the sun is large, any effort to control climate change by human action is futile.
The environmental movement is a great force for good in the world, an alliance of billions of people determined to protect birds and butterflies and preserve the natural habitats that allow endangered species to survive. The environmental movement is a cause fit to fight for. There are many human activities that threaten the ecology of the planet. The environmental movement has done a great job of educating the public and working to heal the damage we have done to nature. I am a tree-hugger, in love with frogs and forests. But I am horrified to see the environmental movement hijacked by a bunch of climate fanatics, who have captured the attention of the public with scare stories. As a result, the public and the politicians believe that climate change is our most important environmental problem. More urgent and more real problems, such as the over-fishing of the oceans and the destruction of wild-life habitat on land, are neglected, while the environmental activists waste their time and energy ranting about climate change. The Paris meeting is a sad story of good intentions gone awry.
The most important fact in the history of the 21st century is that China and India, with about half of the world’s population, are getting rich. To get rich in the next 50 years, they must burn prodigious quantities of coal and add big quantities of carbon dioxide to the atmosphere. China and India have a simple choice to make. Either they get rich and cause a major increase of atmospheric carbon dioxide. Or they stay poor. I hope they choose to get rich. The choice is theirs and not ours. Whatever we may choose to do will not make much difference. The discussions in Paris will not make much difference. The good news is that the main effect of carbon dioxide on the ecology of the planet has nothing to do with climate. The main effect of carbon dioxide is to make the planet greener, feeding the growth of green plants of all kinds, increasing the fertility of farms and fields and forests.
Freeman Dyson is professor emeritus at the Institute for Advanced Study in Princeton.