The biggest danger facing our planet

Some people are very concerned about the future of our planet due to the predicted effects of climate change. Given the strength of scientific concern I think this is to an extent justified, although I think the degree of threat is still debatable, as is what should be done to minimise adverse effects. We need to balance against this probably positive effects, in some parts of the world at least.

I have concerns about climate change, but I’m not convinced it will be catastrophic unless we make huge and urgent changes to how we live as some seem to think.

I think there are greater threats to the planet, and also to human civilisation.

There appears to be a slight chance of a collision with an asteroid or some other piece of debris speeding around or into our solar system, However i think the odds of

A nuclear holocaust is one threat that hasn’t gone away. All it may take is one leader making a stupid decision that escalates. Or one mistake. Oddly most people don’t seem to care about this much any more, while countries like Russia and the US are looking at increasing their destructive power.

But I think there is a bigger threat to our planet. The odds are it won’t happen in our lifetimes, or this century. But it is certain to happen sometime, and with the current levels of human population it could easily be catastrophic.

It has happened before numerous times, including about 1500 years ago – they actually had a double whammy then.

CNN: The worst year to be a human has been revealed by researchers

A team of historians and scientists has identified A.D. 536 as the beginning of a terrible sequence of events for humankind.

A massive volcanic eruption spewed a huge cloud of ash that shrouded the Northern Hemisphere in darkness and caused a drop in temperatures that led to crop failure and starvation, said co-lead study author Professor Christopher Loveluck of the University of Nottingham in the UK.

Then the misery was compounded in A.D. 542 as cold and hungry populations in the eastern Roman Empire were struck by the bubonic plague.

Now, in collaboration with glaciologist Paul Mayewski at the Climate Change Institute of the University of Maine in Orono, Loveluck’s team has identified the source of the cloud.

By analyzing ice samples from the Colle Gnifetti Glacier in the Swiss Alps, the researchers were able to identify atmospheric pollutants deposited over the past 2,000 years, according to the study, published last week in the journal Antiquity.

Substances found in the ice provide evidence that the eruption took place in Iceland.

The eruption and the 542 plague outbreak caused economic stagnation in Europe, which lasted more than 30 years until 575, when there were early signs of recovery, Loveluck said.

There is certain to be another massive volcanic eruption at some time in the future. It could happen in Iceland again. or the Mediterranean. Or Alaska. Or the US or South America. Or Indonesia.

Or New Zealand.

Lake Taupo is in a caldera created by a supervolcanic eruption which occurred approximately 26,500 years ago. According to geological records, the volcano has erupted 28 times in the last 27,000 years.

…several later eruptions occurred over the millennia before the most recent major eruption, which is traditionally dated as about 180 CE from Greenland ice-core records. Tree ring data from two studies suggests a later date of 232 CE ± 5. Known as the Hatepe eruption, it is believed to have ejected 100 cubic kilometres of material, of which 30 cubic kilometres was ejected in a few minutes.

This was one of the most violent eruptions in the last 5000 years (alongside the Minoan eruption in the 2nd millennium BCE, the Tianchi eruption of Baekdu around 1000 CE and the 1815 eruption of Tambora), with a Volcanic Explosivity Index rating of 7; and there appears to be a correlation, to within a few years, of a year in which the sky was red over Rome and China.

The eruption devastated much of the North Island and further expanded the lake. The area was uninhabited by humans at the time of the eruption, since New Zealand was not settled by the Māori until about 1280. Possible climatic effects of the eruption would have been concentrated on the southern hemisphere due to the southerly position of Lake Taupo.

An only southern hemisphere effect would have a major impact on the whole planet – but as “the sky was red over Rome and China” suggests it may not be limited to that.

There is nothing we can do to prevent a major eruption. Can we do anything to prepare, or to mitigate the effects? It could have an immediate and potentially catastrophic effect via sudden natural climate change.

Or should we just carry on arguing about what we are doing to affect climate change?