PETER DITLEVSEN - Professor of Physics, Ice, Climate & Earth at the Niels Bohr Institute

PETER DITLEVSEN - Professor of Physics, Ice, Climate & Earth at the Niels Bohr Institute

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Professor of Physics, Ice, Climate & Earth at the Niels Bohr Institute

What happens if we lose the Greenland ice sheet and pass the tipping points and Earth systems shut down?

If that shuts down, roughly speaking, the climate of Northern Europe would be like the climate of Alaska. So, climate models that actually simulate what happens when it's shut down, would say that England becomes like Northern Norway, which means that food security and things like that will be threatened because you cannot grow many crops in Northern Norway. And other models say precipitation changes, so places that are wet might become dry, and so on. So, these are of course severe consequences for Europe, but in some sense, this is going in the opposite direction of global warming. We're all talking about we're getting into a warmer world, but I'm talking about a cooling here. But the warm water that does not then flow from the tropics into the North Atlantic will stay in the tropics. And there, you're not contra-balancing global warming. There you will have the heating on top of the global warming. And that I see as maybe the largest problem we have is that the tropics become even warmer. And we have to realize if you live in a place where mean temperatures are maybe late thirties Celsius and or rise to the forties livelihood becomes very difficult.

Highlights - MARK MASLIN - Author of How To Save Our Planet: The Facts - Professor, Earth System Science, UCLondon

Highlights - MARK MASLIN - Author of How To Save Our Planet: The Facts - Professor, Earth System Science, UCLondon

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Author of How To Save Our Planet: The Facts
Professor of Earth System Science at University College London

I think the most important thing is realizing how much impact humans have had on the planet. For example, did you know that we move more rock and sediment than all the natural processes put together? We also have created enough concrete already to cover the whole world in a layer that's two millimeters thick, and that includes the oceans. We have also created and make something like 300 million tons of plastic every single year, which we know ends up in our rivers. It ends up in our oceans. And we've also found that microplastics have been found in human blood. So this is the impact we're having all around the world. We've also cut down 3 trillion trees, that's half the trees on the planet. We have doubled carbon dioxide in the atmosphere. We've increased methane by about 150%, which has led to a warming of the planet of about 1.2 degrees Celsius. And If you weigh the land mammals, 30% of that weight is us humans. There are 8 billion of us, and I have to say a few of us could lose a few pounds, but 67% of that weight is our livestock. And just 3% is those wild animals. So in less than 5,000 years, we've gone from 99% being wild animals to less than 3%. That's how much impact we humans have had on the planet.

MARK MASLIN - Author of How To Save Our Planet: The Facts - Professor, Earth System Science, University College London

MARK MASLIN - Author of How To Save Our Planet: The Facts - Professor, Earth System Science, University College London

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Author of How To Save Our Planet: The Facts
Professor of Earth System Science at University College London

I think the most important thing is realizing how much impact humans have had on the planet. For example, did you know that we move more rock and sediment than all the natural processes put together? We also have created enough concrete already to cover the whole world in a layer that's two millimeters thick, and that includes the oceans. We have also created and make something like 300 million tons of plastic every single year, which we know ends up in our rivers. It ends up in our oceans. And we've also found that microplastics have been found in human blood. So this is the impact we're having all around the world. We've also cut down 3 trillion trees, that's half the trees on the planet. We have doubled carbon dioxide in the atmosphere. We've increased methane by about 150%, which has led to a warming of the planet of about 1.2 degrees Celsius. And If you weigh the land mammals, 30% of that weight is us humans. There are 8 billion of us, and I have to say a few of us could lose a few pounds, but 67% of that weight is our livestock. And just 3% is those wild animals. So in less than 5,000 years, we've gone from 99% being wild animals to less than 3%. That's how much impact we humans have had on the planet.