Hawking and Trump
Stephen Hawking thinks President Trump's decision to pull out of the Paris Agreement and the British Brexit decision might trigger a chain of events which leads to the destruction of the world. My question - where is the evidence?
Hawking says Trump's climate stance could damage Earth

By Pallab Ghosh
Science correspondent, BBC News
2 July 2017

Stephen Hawking says that US President Donald Trump's decision to pull out of the Paris climate agreement could lead to irreversible climate change.

Prof Hawking said the action could put Earth onto a path that turns it into a hothouse planet like Venus.

He also feared aggression was "inbuilt" in humans and that our best hope of survival was to live on other planets.
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In its Fifth Assessment Report, the IPCC authors wrote: "The precise levels of climate change sufficient to trigger tipping points (thresholds for abrupt and irreversible change) remain uncertain, but the risk associated with crossing multiple tipping points in the Earth system or in interlinked human and natural systems increases with rising temperature."
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"We are close to the tipping point where global warming becomes irreversible. Trump's action could push the Earth over the brink, to become like Venus, with a temperature of two hundred and fifty degrees, and raining sulphuric acid," he told BBC News.

"Climate change is one of the great dangers we face, and it's one we can prevent if we act now. By denying the evidence for climate change, and pulling out of the Paris Climate Agreement, Donald Trump will cause avoidable environmental damage to our beautiful planet, endangering the natural world, for us and our children."
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And on Brexit, he feared UK research would be irreparably damaged.

"Science is a cooperative effort, so the impact will be wholly bad, and will leave British science isolated and inward looking".
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Read more: http://www.bbc.com/news/science-environment-40461726

There is so much wrong with Stephen Hawking's statement, its difficult to know where to begin.

For starters, the US "commitment" to the Paris Agreement was never going to significantly reduce global CO2 emissions. China, whose emissions already dwarf the USA, demonstrated how they think the Paris Agreement is a joke, when they announced a colossal 20% increase in coal capacity in the next 3 years November last year. Green efforts to cast China as an environmental champion just add to the humour.


In addition to China's heroic effort to emit plant fertiliser, as WUWT recently reported, 1600 new coal plants are currently under construction around the world..

Hawking's suggestion that the USA could somehow lead others into economic hardship by destroying the domestic US economy is and always was a liberal fantasy.

As for Hawking's claim we could end up like Venus, a statement without evidence, even from someone with Stephen Hawking's reputation or from the IPCC, is no more valid than a prognostication provided by a psychic gazing into a crystal ball.

The Earth has experienced far higher CO2 levels than the present day. CO2 levels in the Cretaceous, the age of the Dinosaurs, were 1700ppm - more than 4x today's level. The Earth has experienced extreme warming and extreme cooling, but has never experienced a runaway greenhouse effect which made it totally uninhabitable like Venus.

Gigantic CO2 belching volcanic eruptions which lasted for 1000s, maybe millions of years, huge meteor strikes, the advance and retreat of giant ice sheets - for billions of years since life began, nothing in our violent geological history has managed to shift temperatures outside a range where life is possible somewhere on our planet.

Nothing we have done or are likely to do to our planet can come close to what nature has already done - to what our planet has already endured.

In a few centuries fossil fuel resources will likely be exhausted. At most we shall add a few hundred more PPM CO2 to our atmosphere. Suggesting that our mild contribution to global greening is somehow worse than all the awful geological events of our planet's history is pure and simple fiction.