Long term climate study by NASA using data acquired through a variety of sources including weather stations across the world, ships, and many satellites show an increasingly warming trend in the world over the last 30 year period. The satellite images below show the temperature anomalies. This shows that irrespective of what is causing this trend, the world is getting warming.
Read the full information on NASA website: http://earthobservatory.nasa.gov/IOTD/view.php?id=47628&src=eoa-iotd