It doesn't matter about the small sample size in terms of man's history, that is irrelevant. What does matter, however, is the accuracy of the measurements. There are large concentrations of temperature stations in populated areas, and very sparse recording stations in the inhospitable regions of the world. For example, there are 46 stations responsible for all of Antarctica. That's one station for every 304,000 square km. The same situation can be found in the Arctic, the Himalaya's, the Sahara, the Gobi desert, the Amazon...and yet their global temperature is supposed to be accurate to ±0.05C. The satellite record and the GISS surface temperature record disagree by more than a half degree, and yet we're supposed to believe that GISS is accurate to five one-hundredths of a degree!