I think there are only very few data available that can be counted as direct evidence--temperature measurements for earth, air, or ocean.

I still remember that maybe two years ago the science magazine published a paper saying that previous reports had failed to correctly account for the noise in temperature measurements, now the current report demonstrated that the temperature is rising, globally. I don't give that a damn shit. It is doctoring data, as far as I can see.

The problem is that even though the global temperature is rising, can you answer that it is due to human activities, or just a plain secular trend? The ice is melting, well, fine. Dinosaurs once lived in north pole. Besides, it is also possible that more water may cause the temperature dropping below the current level.