Authors:
Climate models projected stronger warming over the past 15 years than has been seen in observations. Conspiring factors of errors in volcanic and solar inputs, representations of aerosols, and El NiƱo evolution, may explain most of the discrepancy.
Schmidt, G. A., D. T. Shindell, & K. Tsigaridis (2014) Reconciling warming trends, Nature Geoscience 7:158-160.