the reasons that exscuse us have been many and more and more redicolous ranging from cows farting (haha haha) to it being cause by volcanoes,
there a couple of facts to consider:
We are and many don't realize to what extent producing huge quantities of pollution, most of us know that carbon fossils contain carbon this was quite present in our earths atmosphere thousands of years ago (or rather millions) the earth was once under a state of global warming but the trees gradually used it up and stored it then died and because coal and other fossil fuels, so now what are we doing ? letting it all out again it's that simple isn't it just go back to junior school and elementry natural history lessons.
Also another factor being overlooked this is called global warming - WARMING heat not only do we make CO2 emmisions that traps heat but we make heat lots of it we are warming our own planet up we do nothing but burn for energy conversions and various industrial procedures we do nothing but make nude crude heat what ever we do we make heat, the combustion engine is 30 % efficient that means that our lovely powerful 50 KW engines are turfing out over 100 KW or heat and hour, the same goes for the production of electricity most methods are 25-30 % efficient for every KW of power we use up to 3 KW of heat has already gone into the atmosphere and how many of us use that measly 1 KW that is left to cook with or warm our homes making yet more heat. for a full list and please give me your suggestions on the article read here on my site:
The future between renewable energy and pollution
as for volcanoes what about all those underground nuclear testings we do don't all these underground explosions disrupt things how come the americans already knew about the tsunami 6 hours before yet after it was said so how do we detect it in the future ?: difficult because the water only rises by 1 cm at the epicentre and becomes a 30 m wave near the shore at the last minute yet america knew 6 hours before that it was going to happen how ? what where they up to ?