Global warming is a man made problem. Man have interfered with the earth's natural habitat. Man have cut trees in large numbers and have not re-planted them. Man have dug large trenches and overused areas of land which have led to many challenges on the earth's surface.
Global warming is a man-made problem. There is irrefutable scientific evidence to prove that human intervention has led to an increase in average temperature and carbon dioxide levels. It is agreed that there may be some natural phenomena (cyclic increase and decrease in solar radiation, etc.) that may have contributed; however, human intervention has caused much more damage.
Since the arrival of the industrial age, we have been consuming much more fuel (coal, wood, etc.) to run our industries. The human population has grown at a tremendous rate in last couple of centuries, mush faster than any other time in history. Additionally, more populous countries are now growing rapidly (in terms of economic development); examples are India and China, which together are home to about 2.5 billion people. Industrial growth requires more fuel, better infrastructure and similar activities, all of which generate carbon dioxide and cause global warming. Even the growth of food crops and the rearing of animals (especially ruminating animals) causes global warming by the release of greenhouse gases.
Hence it is human intervention that is causing global warming and not nature.