This is yet another reason why man made global warming scientist are getting warmer tempitures to show the earth is warming. The PROBLEM is the data they are using is falty and very misleading. Their samples are from cities and not more remote areas. Cities have been and are well known to be much warmer then more remote areas, it is called the "urban effect". For those that dont believe this just check out your next weather forcast it always shows the cities as warmer then the surrounding areas.