Comparing climate projections to observations up to 2011

Environmental research letters, volume 7, number 4:

This article analyses global temperature and sea-level data for the past few decades and compares them to projections published in the third and fourth assessment reports of the Intergovernmental Panel on Climate Change (IPCC). It focuses on the two prime indicators of climate change: the evolution of global mean temperature and sea level.

The results show that global temperature continues to increase in good agreement with the best estimates of the IPCC, especially accounting for the effects of short-term variability due to the El Nino/Southern Oscillation, volcanic activity and solar variability. The article states that the rate of sea-level rise of the past few decades, on the other hand, is greater than projected by the IPCC models, which suggests that IPCC sea-level projections for the future may also be biased low. It also highlights the need to thoroughly validate models with data of past climate changes before applying them to projections.