It is widely being reported that, based on surface-temperature data from the National Oceanographic and Atmospheric Administration (NOAA) and the National Aeronautics and Space Administration (NASA), 2010 was tied for the warmest year on record. What is not so widely reported is that those surface temperature data have been so shamelessly manipulated by climate alarmists that they are entirely unreliable. For a short course in one of the great scientific scandals of all time, go here.
There are a number of things wrong with the data produced by NOAA and NASA, but one of the most basic involves the urban heat island effect. It it commonly understood that cities are warmer than the surrounding countryside; you see that every day in weather reports. Thus, weather stations located in urban areas, as many of them are, tend to show increasing temperatures as urbanization and changing land use make the immediate area of the weather station warmer. One study indicated that even a tiny village of 1,000 people can warm temperatures by up to 3.8 degrees F.
Follow the link to see charts.