Scientist warns of end of life on Earth
A NORTH Queensland scientist has warned life on Earth is in danger if immediate action is not taken.
Cairns-based professor Jeff Sayer made the stark warning after research was published which showed the global scale of agricultural production had already breached two crucial "boundaries" that could endanger human existence.
The professor is part of an international team examining agricultural production in relation to nine "planetary boundaries", which if breached could destabilise the Earth's ecosystem.
The research examines threats to human life including climate change, the biosphere, biochemistry, freshwater and land systems.
"Agricultural production occupies 40 per cent of the land surface of the Earth that isn't covered by ice, and that's expected to increase by another 8 per cent by 2050," Prof Sayer said.
He said agriculture was already overwhelmingly responsible for breaching accepted biogeochemical limits - the flow of chemicals such as nitrogen and phosphate between living and non-living organisms.
The nine Planetary Boundaries
1. Land-system change (increasing risk)
2. Freshwater use (increasing risk)
3. Biogeochemical flows (breached)
4. Change in biosphere integrity (breached)
5. Climate change (increasing risk)
6. Ocean acidification (safe)
7. Stratospheric ozone depletion (safe)
8. Atmospheric aerosol loading (safe)
9. Introduction of novel entities (safe)
Prof Sayer said the best way to prevent catastrophe was to make more efficient use of chemical inputs to agriculture - pesticides and fertilisers - for the biogeochemical flows and to manage protected areas to conserve biosphere integrity.
"However the full answers to these questions are much more complex and context dependent - and they need a lot of research and innovation in agricultural and land management systems," he said.
End of the Earth
Although the professor's paper has dire warnings for human life on Earth, life in general is expected to last for another 100 million years.
But many things could potential destroy life on Earth including a massive volcanic eruption.
Also an enormous asteroid could split the Earth in to pieces. That could happens within 450 million years.
Anytime within the next million years, a wandering star could pass close to the Earth, destroying life on the planet.
Eventually the sun will expand and swallow the Earth.
Scientists predict that will happen between 1 and 7.5 billion years from today.
Hopefully by that time humans will have developed technology to enable us to colonise other planets.
The Earth's core could solidify, which could take about three to four billion years.
Read the paper yourself here.