The Earth has gone through massive changes in its 4.5 billion-year history. Its climate has naturally fluctuated between being very cold and covered in ice, or very hot. In the past 10,000 years the planet’s climate has become much more stable, leading to flourishing flora and fauna, and the subsequent population explosion of humankind.
However, over the past 50-100 years, increasing industrialisation and human activity (such as industry, agriculture and transportation) have begun to affect the natural climate balance. These activities are increasing the amount of greenhouse gases in our atmosphere and causing Earth not only to heat up, but to heat up at an unprecedented rate.
Since the start of the industrial revolution (about 1750) the overall effect of human activities on the climate has been a warming influence. The human impact of this era greatly exceeds that due to known changes in natural processes such as solar changes and volcanic eruptions.
Scientists are now detecting changes which suggest the climate is becoming hotter on average, and more variable. This variability is being attributed in part to increased levels of carbon dioxide in the Earth’s atmosphere. According to scientific studies, in the past 650,000 years the planet has never had so much carbon dioxide in its atmosphere as it does today, and the levels are continuing to rise.