We are living in a period with a significant trend of global warming - not natural at all, despite what many people would have you believe. Global warming and cooling are indeed natural phenomena, but when they happen either in geologic time (by far the most common), or due to some catastrophic event (say a volcano spewing ash into the atmosphere, blocking sunrays). The evidence is numerous, and easy to spot, but alas, denial seems to be sprouting eternally. Just take a look.
An approximately one degree growth in 40 years - that's absolutely huge! Don't be tricked by this apparently small difference - the results are indeed huge. It's this extra degree which causes droughts, ice melt, hotter oceans - and this is no coincidence. It's not that it just happened to be hotter this time of the century, the trend is clear, as you can see from the chart below, illustrating the hotter years since 1850. As you can see, hotter and cooler years mingled outside their periods, but the general trend can be seen from the Moon: we are living in the hottest decade since mankind imposed itself as the dominant species. The decade before had been the warmest, and even the decade before that took this prize, but never before has this been so obvious as nowadays.
Still not buying it? Maybe this is more clear.
If you're still not convinced, here's what you should probably know. The Koch brothers, who own Koch Industries make billions from manufacturing, distributing and refining petroleum and other related products. They, along with Exxon Mobil, the largest private-held oil company, spend millions of dollars each year to fund studies that show how we are not passing through a period of global warming, or if we are, that has absolutely nothing to do with us - 9 out of 10 climate deniers can be linked with Exxon Mobil. This summer, Koch Ind. funded a study which backfired: the study clearly showed the earth is heating, and most, if not all the damage was caused by us humans.
But this is just the land mass! If you actually think land has the biggest problems... then you are in for a big surprise! Here's how much the oceans are affected:
If you just take a quick look at the studies conducted on oceanic temperatures, you'll see that remarkably, all of them have the same conclusions: oceans are heating up massively.
But it's not all about the landmass and the oceans; what's happening in the Arctic areas? I mean, it's only 0.8% of the total warming, how bad can it be? Oh, it's bad.
There is not part of the Earth left untouched - nothing! We have to stop thinking about our planet in terms of countries and continents; everything is connected, everything everyone does everywhere actually affects everyone everywhere. So the first step towards undoing as much as the damage as possible is acceptance - we have to accept we are responsible for this - it's a done deal. Nothing can be changed about the past, but we can change the future. If we continue in these lines, the extent of the harm will be too much to undo, we will suffer. The planet will be just fine but we, humans, won't - and that's why we have to change our ways and move on towards a sustainable future.