Along the same lines as a celestial impact comes environmental collapse of the Earth. There are several different aspects to an environmental collapse, and any one of the following things can be a major factor in this, but one of the major factors right now is the issue of global warming (http://en.wikipedia.org/wiki/Global_Warming). Global warming is a huge theory that deals with the end of the world as we know it. While there are many different scientists and scholars that disagree on the issue, there are scientific facts to prove that our planet is getting a little warmer than usual. But, nothing so significant that would cause a mass extinction or major problems with the life on Earth.
Global warming has so many different theories and factors that it is almost impossible to pinpoint exactly what causes it and what will cause it to accelerate, therefore causing major damage to the Earth and everything living upon it. Some scientific studies have concluded that there are several factors that contribute to the global warming theory, which include: volcanoes, carbon dioxide, a thinning of the ozone layer, increased solar activity, and greenhouse gases. Everyone of these items, plus several other theories, have aided in the reduction of some of the polar ice caps on our planet. While there really is not enough of a “meltdown” to cause a mega-panic, it is something that is happening. Movies and doomsday media have helped to play up the global warming theories by stating that the ice caps are melting rapidly and that coastal countries will soon be flooded and so on.
Some scientists predict that if global warming accelerates, there will be major impacts on the Earth. This includes not only a rise in the average temperatures of the Earth, causing extinction of several species that dwell in desert areas around the Equator, but the loss of crops that grow in these areas and areas that connect to them. A rise in the temperatures around the globe will also result in a rise in destructive weather patterns that involve warm and cool air to create such major disasters as hurricanes and tornadoes. It will also have a major effect on the ecosystems around the world, as some species are forced out of their natural habitats and into others, either to become extinct or to overrun the other species that already live there.
While global warming will effect the temperatures of the Earth itself, it will also effect the glaciers and the oceans as well. Of course a rise in average temperatures around the world will begin to melt the glaciers and polar ice caps, increasing the amount of cold water that is dumped into the oceans. Although this might not seem like a big deal, on a global scale, it can cause major problems. With the glaciers and ice caps melting, the resulting cold water will only run toward the ocean to mix with the warmer water there. This change in temperatures in the oceans will cause a shift in the currents and the patterns that the oceans have had for millions of years. Any change in the oceans themselves will cause major changes in the weather patterns as well, causing monster hurricanes and huge weather systems that will sweep the planet.
Needless to say, there are many doomsday theories that are based on global warming, where scientists predict that the Earth’s average temperatures will rise rapidly for no reason and melt every ice cap and glacier in the world, causing major catastrophes all around the Earth and causing mass extinctions as well.