3. From GCSE Bitesize… The destruction of the rainforest is: … .reducing world-wide biodiversity. almost certainly as there are very many species unique to different rainforests in different parts of the world. … increasing ozone in the atmosphere. myth as this is due to chemicals (CFC's) released into the atmosphere by people. … increasing the greenhouse gas carbon dioxide in the atmosphere. likely but this is a minor effect compared to burning fossil fuels for industry and transport. … increasing global warming. possibly but this is really uncertain as climate change is natural. (There have been cold and warm periods on Earth in the past)
4. From GCSE Bitesize… The destruction of the rainforest is: … reducing the amount of oxygen that people can breathe. myth , there is plenty of oxygen in the air for people to breathe. … losing valuable genetic material that may be useful to people in the future. likely - pharmaceutical companies are searching for valuable medicines and drugs in rainforest areas. Agricultural companies are also looking for wild strains of crops to cross with domestic crops. If species become extinct, then genetic diversity is lost. … affecting the weather patterns across the globe. possibly , the changes in humidity in deforested areas are creating less rainfall and having knock-on effects on savanna climates to the North and South. Rainfall is becoming more unpredictable. Exam tip To get a higher grade - you need to look at the scientific evidence about some of the common claims about the importance of the rainforest to the planet. There is a lot of propaganda about.
7. Scientific uncertainty This is only a possible theory. An uncertainty is when scientists cannot know for sure, due to other possible ways the Earth can react. In this case, increase in temperatures may cause a decrease in biodiversity because these new temperatures may go beyond what the current species can tolerate. If the temperature change is gradual, this model may be right. But if the change is sharp (as it is today), then this rapid increase may not give species time to adapt. (Assuming NO human interference to the ecosystem)