Global warming is happening so rapidly because of enhanced greenhouse effect, scientists believe. Human induced climate change is caused due to the changes in atmospheric composition with addition of more and more greenhouse gases like carbon dioxide, methane and oxides of nitrogen.
These additional greenhouse gases in the atmosphere causes extra absorption of solar radiations and amplifies the heating of earth. A good absorber of heat is also a good emitter and therefore the amount of heat that these extra greenhouse gases absorbs will be released into the atmosphere upon emission. This amplifies the heating of our atmosphere and caused a temperature rise on earth’s surface.
These amplifying effects are called Positive Feedbacks. One positive feedback will induce changes in other cycles and cause more positive feedbacks. e.g when the atmospheric temperature rises, glaciers starts melting and extra fresh water is added into the oceans and raises the absorption of solar heat which is another positive feedback. These positive feedbacks when combine, amplifies the effects of global warming.
Global Warming 101 – National Geographic Documentary
Embedded below is a documentary film on global warming by National Geographic channel which explains why global warming is happening so rapidly and how our earth’s ecosystems and natural habitats are changing due to global warming. Retreating glaciers & ice sheets, sudden climate changes, intensifying natural disasters and rising average temperature of earth’s surface are a few major environmental issues that are the direct impacts of global warming.