In this video Tony Heller shows us how NASA changes it's data record over time. The cooling that took place from around 1945 until 1975 has simply been ereased from the historical temperature data they publish now. Other agencies follow suit, they make similar adjustments to their own data sets, creating a fake sense of consensus.
Tony proves the cooling really happened showing historical newspaper articles. The data can be tampered, but the written history can not!