Carbon emissions, CO2, greenhouse gases, climate change: in recent times, hardly a day goes by without us being bombarded with dire warnings that life as we know it will cease to exist if we carry on living as we do, irresponsibly consuming energy in a way that causes a build-up of heat in the earth's atmosphere, which will eventually result in irreversible climate change.
But is it true, or are we all the victims of an elaborate hoax? The debate around global warming is based on our understanding of the way certain gases in the earth's atmosphere trap heat from the sun, acting like a giant greenhouse - hence the term.
Carbon dioxide (CO2) is one of the main greenhouse gases, and is also one of the products of combustion.
Scientists have ways of measuring the amount of CO2 in the atmosphere and comparing it to historical levels, and the evidence points to the fact that there is now more of the stuff in the atmosphere than at any point in the last half a million years.
There may be other contributing factors, but most would agree that man's industrial activity is the primary cause of this increase.
Why is this a bad thing? The general consensus is that the polar ice-caps will melt, resulting in higher sea levels and flooding of fertile coastal areas.
Weather patterns are also likely to be disrupted, resulting in greater extremes which will affect human settlements and importantly, food production, leading to mass starvation and upheaval.
But while most scientists agree that global warming is a real and imminent threat, there are those who believe that any climatic fluctuations we may be observing are nothing more than long-term cycles that have been going on since before mankind ever set foot on the earth.
They argue that the debate is being deliberately fueled by those who stand to benefit politically or economically from a population that is sufficiently motivated by fear to change our collective lifestyle, for therein lies opportunity for them to seize power and enrich themselves.