Question

Lily was concerned about global warming and its effects on Earth. A changing climate is associated with multiple kinds of changes to Earth. Lily was especially concerned with the cascade effect. Explain the cascade effect, and give two specific examples of phenomena that might occur due to a changing climate.

Answer 1

A cascade effect is an inevitable and sometimes unforeseen chain of events due to an act affecting a system. If there is a possibility that the cascade effect will have a negative impact on the system, it is possible to analyze the effects with a consequence / impact analysis. An example of the cascade effect caused by the loss of a top predator is apparent in tropical forests. When hunters cause local extinctions of top predators, the predators' prey's population numbers increase, causing an overexploitation of a food resource and a cascade effect of species loss. Another example is a lake system with four trophic levels, the model predicts with the removal of the top carnivore, the primary carnivore numbers will increase, in turn, reducing the number of herbivores, increasing the phytoplankton abundance, and decreasing the levels of mineral nutrients. The effects show a positive/ negative change in trophic level structure as it moves down.