Anglų referatas. Human impact on oceans and seas. Ocean acidification - acid rains affecting oceans. Ocean pollution. Water resources - what can we do? Ecological problems. Ecology and ecological problems. Ecological problems - true crisis of humanity. Forests - nature's answer to global warming. Antarctica - effects of global warming. Water resources - what can we do? Old tropical rainforests disappearing fast. Antarctic sea life vulnerable to warming. If we stop emitting climate will soon return to normal? Trees dying in united states. Global warming is real despite cold winter. Tremendous decline of rockhopper penguin population. Animal poaching in africa. Amazon rainforest - deforestation. What is global warming? Global warming - already a certainty. Usa - mainly responsible for global warming. Global warming in africa – who's to blame, what to do? Clean energy - earth's only chance against global warming. Is global warming serious problem? What do people think? Environment - definition and meaning. Future of our planet lies in our hands. Endangered species - caribbean corals. Ecological problems - true crisis of humanity.
Oceans and seas - even worse condition than expected
Water scarcity map (click on picture to enlarge)
Tropical rainforests are very important from many different points of view, first of all they produce somewhere between 20-30 % of the world's oxygen, they absorb carbon and help regulate climate, and they also contain 80 percent of the planet's terrestrial biodiversity. Long long time ago forests use to cover 20 million square kilometres, today 12 million were already cleared, and another five million have been selectively logged.Latest satellite observations have shown that about 350,000 square kilometres of the original forested areas are growing back which is very small compared to size of cleared areas. The good news is that this number could increase in years to come because of large-scale migration of people from rural areas into cities in tropical areas. This would give new forests more areas to grow and could provide habitats for rich biodiversity that would otherwise be lost permanently.
Old, ancient tropical rainforests are disappearing fast
However in order for second-growth forests to provide shelter and habitats for different animal and plant species they have to be connected with old-growth forests so species can move to them. Of course old ancient forests are of the best quality, for instance they are not so fire prone like secondary forests because they are more humid.Even though second-growth forests have potential to at least partially replace old growth forests it has to be said that main causes of deforestation such as logging, mining, industrial agriculture will also harm secondary forests. But of course the most important thing of all is to preserve old ancient rainforests because deforestation of irreplaceable old growth forests is happening faster than any time in history (Borneo, Indonesia, Amazon rainforest).
World has very much become aware of the fact that we have to reduce greenhouse gas emissions in order to fight against global warming. There are many people believing that once we reduce our current greenhouse gas emissions levels climate will very soon return to normal condition. Unfortunately for us, scientists are not that optimistic.Latest study carried out by the National Oceanic and Atmospheric Administration's (NOAA) Earth System Research Laboratory in Boulder Colorado has come up with rather unpleasant news about the damage that has been done to climate, and the time needed for recovery. Dr. Susan Solomon, lead author of this study believes that damage is too big, and that this damage is probably irreversible.
According to this study even if world manages to significantly reduce greenhouse gas emissions on global level, temperatures are still very likely to remain high this millennium, and it will take more than 1000 years to see significant climate changes. Climate change is slow process, and we'll have to wait for a "while longer" to see positive changes.Although scientists believe that climate change is irreversible process that will happen even if we reduce greenhouse gas emissions we still have duty not to make things even worse than they are now. This is the reason why world has to react very quickly, and do necessary changes to reduce current greenhouse gas emission levels. We may not be able to fix this problem right away but we sure do not want to make it worse than it already is.