Global Warming – Natural or Not?
A BBC news story (January 6, 2006) suggests that:
A rapid rise in global temperature 55 million years ago caused major disruption to ocean currents, new research shows. Scientists found that the disruption took 140,000 years to reverse.
Writing in the journal Nature, the scientists say the phenomenon may be important for understanding the impact of present day climate warming.
The new study, by Flavia Nunes and Richard Norris from the Scripps Institution of Oceanography in La Jolla, California, looked at tiny fossil animals called foraminifera in marine sediments from 14 ocean-floor locations around the world.
Analysing the ratios of two isotopes of carbon in the shells of these foraminifera allowed them to determine ocean current patterns at the time the creatures died.
The time in question was an extraordinary epoch in Earth history – the Palaeocene-Eocene Thermal Maximum (PETM), when the global average temperature rose by anything between four and seven Celsius in a few thousand years.
Computer models of modern climate suggest that temperature changes could affect ocean currents, and recent research has found indications that it is happening now in the north Atlantic.
The reason why temperatures shot up during the PETM are unclear; but carbon dioxide concentrations in the atmosphere appear to have been extremely high, about a thousand times higher than currently.
One theory is that an initial warming changed the distribution of heat in the oceans so that deposits of gas hydrates on the sea floor were released, with carbon dioxide and methane rising to the surface and entering the atmosphere, causing further greenhouse warming.
Some researchers have raised concern that release of gas hydrates could contribute to present-day global warming.
Sounds feasible, and sounds like it points to the possibility that the current trend in CO2 levels is not the responsibility of our pollution, although our pollution is not helping and may be accelerating the natural cycle. However, the continued pressure from world government’s to introduce taxes on the use of fossil fuels as an attempt to curb their use and reduce pollution to “save the planet” seems a little shortsighted and just another way to generate revenue from our decreasing oil supplies.
We have already proven that we have the technology to build vegetable-oil fuelled cars (and people have been prosecuted for converting their cars to this alternative in the UK) and so use a cheaper, cleaner, renewable energy source instead of the one that is the source of the pollution. Makes you wonder, doesn’t it?
And then today, we get another news story that US scientists think that a good way to deal with the build up of CO2 is to capture it any bury it at the bottom of the ocean. Now go back and read the excerpt from the January news story that suggests that as global warming progresses, gas hydrates are released from the sea floor and so speed up the cycle. Burying tonnes of CO2 will surely be just a time-bomb waiting to explode? Not to mention problems of leakage, sabotage, or even the long-term possibility of deliberately creating a cataclysm to introduce a new world order (see the film Sky Blue, aka Wonderful Days).