when is global waring going to start harming the earth?

As you have said, it is happening now, and it will continue to happen. We can never stop it but we can slow down the process by taking more care of the environment. There is not going to be any dramatic change but there will be more floods, more droughts, extremes of temperature and every year more species become extinct. Your children and your grandchildren will live in a world with fewer resources and more poverty due to high fuel costs and food shortages. Coastal areas and island will not disappear overnight, but rising sea levels and flooding mean more people will be driven inland, which will put pressure on water supplies and could increase disease and poverty. There is no beginning and no end to it. We need to do all we can now, and in the immediate future, to preserve what we have and find alternatives to what we can no longer maintain. The time will come when the planet can no longer sustain us, but there is no way of knowing how long it will be before this happens. It could be tens of thousands of years or sooner. There is no definite answer.

I still concern this same question,but I think global warming is harming our earth now.the ice is melting,the temperature is higher,and some diseases are breaking out,and so on,I think this is the result of global warming.But fortunately,there are more and more country concern this question,more and more people including those in the developing countrys realized this question,so I think we should keep optimism.

It is already in effect with phase.But the scientist have roughly calculated that in 2030 and upcoming years,there will be many disasters no one have thought about.It will be like hell to live on earth.Thanks to the precautions and awareness created among the public