Low sun activity is cited as the reason. In recent measurements, sunspot activity, intense solar eruptions caused by magnetic activity, has been astonishingly lower than predicted, which translates into a period of cooling — what scientists dub a “little ice age...” (read more)But who really knows? It's always a bit dicey trying to predict the future. Current sunspot activity may not necessarily be an indicator of future sunspot activity. As Danish physicist Niels Bohr once said, "Prediction is very difficult, especially about the future."
It seems to me, however, that sunspot activity - which of course is wholly beyond our control - is likely to have far more to do with global temperatures than human activity (with the possible exception of all the hot air emitted by Al Gore).