Climate change is term that refers to any significant and long-term change in average weather in a given region or entire Earth. Basically every significant variability of average weather over longer time period can be classified as climate change. In the early beginnings of Earth's history these changes were usually caused by different dynamic processes on Earth and recently by human activities.
This is the reason why term "climate change" refers in everyday talk to "modern climate change" or climate change caused by global warming. The most sensitive indicators of climate change are glaciers and they are currently melting at rapid level which means climate change has already started. And this time only because oh human activities that resulted in global warming phenomenon.
Global warming has today even become synonym for climate change because of its role in climate change as excessive emission of harmful greenhouse gases into atmosphere caused increase in average temperature that affected climate on Earth. And while fossil fuels remain dominant their combustion will continue to emit CO2 and other greenhouse gases into atmosphere and cause even more serious consequences to climate change.
As the temperatures rise globally we can expect serious changes in weather patterns, rising sea levels and not before seen frequency and intensity of extreme weather. The most vulnerable areas are around Earth's poles and Africa, and these areas are already experiencing significant increase of average temperature, with worse to follow.
The United Nations Environment Programme states "climate change impacts will range from affecting agriculture- further endangering food security-, sea-level rise and the accelerated erosion of coastal zones, increasing intensity of natural disasters, species extinction and the spread of vector-borne diseases."
The sad fact is that we can't prevent climate change, we can only try to adapt to it as this is something that already started and could only get worse. We caused global warming and now we are faced with the climate change as the greatest environmental challenge of them all. And though we are already aware of climate change we still lack action to prevent further increase of greenhouse gases in the atmosphere. There is lot of talk, but very little action and the possible solution (turning to renewable energy sector) is still negligible when viewed on global scale and constant increase in energy demand isn't helping either since fossil fuels are still dominant energy sources for most of the world's industry. According to different estimations, agreements, protocols and government policies of many countries, this turning to renewable energy sector should change in years to come. But do we have this luxury of "years to come"? Is time still on our side?