Have you noticed lately there's been a rather big shift in attitudes towards climate change?

Two years ago, there was a huge groundswell of support for the theory that global Warming equals climate change. It's been a time when the Intergovernmental Panel on Climate Change almost unanimously agreed climate change is happening and humans are making a significant contribution.

But there have been a lot of opposing views from equally credible sources, so for a lot of us it's become very confusing. Who and what do we believe?

One thing is for sure, climate change is nothing new. It's been going on since time began and this is yet another spanner in the works.

A good example happened in our own backyard not that long ago. In 1991, Mt Pinatubo in the Philippines erupted and created a sulphuric acid haze that reached into the stratosphere.

Immediately, it spread further through the atmosphere and within two months, the ash was affecting most of the world.

It actually impacted Australia, with more vivid and dramatic sunsets and sunrises. That happens when light from the sun passes through the atmosphere and scatters off the added particles, creating brighter colours.

But the real impact was felt over a much larger area. It's thought for two years after the Mt Pinatubo eruption, the world's climate actually cooled, because the large ash clouds refected heat back into space.

So in theory, the climate changed, but unlike the current thinking, it was without any human intervention.

History has many similar tales to tell. In 1783, Benjamin Franklin noticed after a vocanic eruption in Iceland, sunlight directed through a magnifying glass no longer set fire to a piece of paper.

In 1815, after a huge eruption near Borneo, they went through a period known as "the year without summer", again because of the cooling affect of the volcanic ash.

So the debate goes on, but in many ways a lot of this is certainly nothing new.