The first question is: is global warming happening? It does appear that the climate is becoming more subject to extremes. Some parts of the planet are getting warmer, other parts of getting colder. Perhaps we are warming, but a better discussion title is probably “climate change”. That isn’t new. The climate is constantly changing, but the current complaint is that it is more changeable and the weather is more extreme than it used to be.
The current concern is: if it is underway, is human activity largely responsible for global warming? This is a great question to consider because it is a highly controversial topic and very political. Despite all our scientific progress it is quite hard to model temperature change on a global scale. There doesn’t seem to be any doubt that in recent years the planet has been getting warmer, but is human activity solely responsible for this? Ian Plimer’s book Heaven and Hell provides thousands of counter arguments based on geological evidence in an attempt to prove that global warming is a natural event.
Geological temperature records for the planet show that we are emerging from an unusually cool period. For hundreds of millions of years the average planet temperature has been 5 to 10 degrees warmer than in the last 5 million years.
Is the rise in temperature due to greenhouse gas emissions, or something else – sun or galactic activity, the absence of volcanic activity?
Do some research and make up your own mind. It is a great topic to exercise your higher mental faculties. Some links for further reading: