The author of today"s post, Lisa Moore, Ph.D., is a scientist in the Climate and Air Program.
Climate models are usually run far into the future, projecting temperature changes to the end of the century. Over the long term, the effects of greenhouse gases overwhelm all other factors. But climate can have substantial "short-term internal variability" – for example, temperature shifts due to El Niño and La Niña. Climate models have never been able to predict this internal variability – until now.