Melting of the polar ice caps will cause coastal and low-lying land to be flooded. Global warming may also cause untold damage when it modifies the ocean currents or even result in a breakdown of the delicate and complex weather systems.
In the course of only 150 years the amount of carbon dioxide released into the atmosphere by humans has exceeded the amount of carbon dioxide stored in the entire biomass and all the oceans of the world. THE SUDDEN RISE OF ATMOSPHERIC CO2 LEVELS COINCIDES WITH THE INDUSTRIAL REVOLUTION AND THE POPULATION INCREASE.

Example Five: Overpopulation => Overfishing and Pollution of the Oceans
Take the problems we are causing to the oceans, our ancient cradle.
We deplete the marine life we need to feed the growing millions as well as its nutrients, among them the phytoplankton that produces much of the oxigen we breathe.

We have known the circuit, called the food chain, for many years. Yet we interfere with it by taking fish out of the oceans faster than they can reproduce. At the same time we poison their source of food.