The Future of Humanity according to Stephen Hawking
As reported by the Sydney Morning Herald, the famous physicist (Black Holes) Stephen Hawking recently took off in a Boeing 727 that “roared over the Ocean and curved large parabolic arcs in the sky”, producing the effect of floating in zero-gravity, like being in space.
Before taking off he said life on Earth was “at the ever increasing risk” of being overcome by disaster, “such as sudden global warming, nuclear war, a genetically engineered virus or other dangers. The human race has no future if it doesn’t go into space.”
Note the sudden global warming, which may be due to chaotic fluctuations, something to my knowledge often neglected in modelling. Chaotic fluctuations are determined by very small initial conditions and are largely unpredictable (though strictly deterministic). Let’s hope Stephen Hawking is wrong, and - if not - let’s hope we have sufficient time to get ready for space travel on a large scale.
April 28th, 2007 at 6:07 pm
> Let’s hope Stephen Hawking is wrong, and – if not - let’s hope we have sufficient time to get ready for space travel on a large scale.
Don’t you think those two are mutually exclusive? Large scale space transport would emit greenhouse gases on an unprecedented scale.
April 29th, 2007 at 2:29 pm
You are the engineer and know this better, but perhaps future generations can produce and assemble space vehicles in space and make them blast off without affecting Earth. On the other hand, perhaps the ultimate catastrophe is due to one of Hawking’s other options and not to greenhouse gases, and future generations will blast off just before catastrophe strikes (who would worry then about greenhouse gases). Of course all sheer ill-founded speculations, which could be taken straight from a SciFi novel. Why not write a story about it, perhaps a bestseller?
May 1st, 2007 at 5:13 pm
Here are some recent news (extracts) from the BBC 30.4.07 about climate change.
Arctic ice is melting faster than computer models of climate calculate, according to a group of US researchers.
Since 1979, the Arctic has been losing summer ice at about 9% per decade, but models on average produce a melting rate less than half that figure.
The scientists suggest forecasts from the Intergovernmental Panel on Climate Change (IPCC) may be too cautious.
The latest observations indicate that Arctic summers could be ice-free by the middle of the century.
They also calculate that about half, if not more, of the warming observed since 1979 originates in humanity’s emissions of greenhouse gases.
May 18th, 2007 at 1:21 pm
Here is some further information about the dangerously accelerating climate change. Extracts from:
Deborah Smith, Sydney Morning Herald 18.5.07, Ocean has less ability to soak up emissions (based on an article in “Science”)
CLIMATE change has reduced the Southern Ocean’s ability to soak up carbon dioxide, leading scientists to warn that global warming will accelerate more rapidly than thought.
Since 1981 the ocean has absorbed about 15 per cent less of the greenhouse gas each decade than had been predicted, research shows.
Paul Fraser, of CSIRO Marine and Atmospheric Research, said the find meant levels of greenhouse gases in the atmosphere would be higher in future than recently predicted by the Intergovernmental Panel on Climate Change, because the find had not been incorporated into its deliberations.
The team concluded that an increase in the strength of the winds over the Southern Ocean since 1958, caused by human activity, was the main reason for the reduction in the ocean’s ability to soak up carbon dioxide.
Greater turbulence on the ocean’s surface increased the amount of carbon dioxide released from the water into the atmosphere, reducing the overall uptake of gas by the ocean.
The researchers concluded that the continuing decline in the efficiency of the Southern Ocean sink during the next 25 years would affect carbon dioxide levels for several centuries to come.
Acidification of the Southern Ocean was also likely to reach dangerous levels earlier than the projected date of 2050, Dr Le Quere said.
A report by the Intergovernmental Panel on Climate Change this month concluded that global emissions would need to be slashed between 50 and 85 per cent by 2050 from the levels in 2000 to limit global warming to two to three degrees and prevent dangerous climate change.