Life on Earth may die out in one billion years
SCOTLAND : Armageddon! All animal and plant life may vanish from the
Earth within the next one billion years, a new study has predicted.
However, ironically the end of the world is going to arrive as a
result of too little carbon dioxide in the atmosphere, rather than too
much of the gas, researchers say.
According to the study by astrobiologist Jack O’Malley James of the
University of St Andrews, within the next billion years, increased
evaporation rates and chemical reactions with rainwater will draw more
and more carbon dioxide from the Earth’s atmosphere.
The falling levels of CO2 will lead to the disappearance of plants
and animals and our home planet will become a world of microbes.
The main driver for these changes will be the Sun. As it ages over
the next few billion years, the Sun will remain stable but become
steadily more luminous, increasing the intensity of its heat felt on
Earth and warming the planet to such an extent that the oceans
evaporate.
“The far-future Earth will be very hostile to life by this point. All
living things require liquid water, so any remaining life will be
restricted to pockets of liquid water, perhaps at cooler, higher
altitudes or in caves or underground,” said O’Malley-James.
This life will need to cope with many extremes like high temperatures
and intense ultraviolet radiation and only a few microbial species known
on Earth today could cope with this.In his new work, O’Malley James has
created a computer model to simulate these extremely long-range
temperature forecasts and has used the results to predict the time-line
of future extinctions.
The new model not only tells us a lot about our own planet’s future,
but it can also help us to recognise other inhabited planets that may be
approaching the end of their habitable lifetimes.
“When we think about what to look for in the search for life beyond
Earth our thoughts are largely constrained by life as we know it today,
which leaves behind telltale fingerprints in our atmosphere like oxygen
and ozone. Life in the Earth’s far future will be very different to
this, which means, to detect life like this on other planets we need to
search for a whole new set of clues,” O’Malley-James added.
O’Malley-James made his bleak forecast at the National Astronomy
Meeting at the University of St Andrews, Scotland.
- DECCAN HERALD
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