The results are presented in a paper, said to be penned by the wizard Radagast the Brown, a Tolkien character the team describe as "probably the first environmental scientist".
In the paper, carried out in the scientists' own time and not funded, Radagast explains that the elves set sail from the Grey Havens as the prevailing winds were favourable for their journey for the West.
He claims the existence of a dry climate east of the Misty Mountains was because the mountains cast a rain-shadow over the region.
Dr Dan Lunt says: "This work is a bit of fun, but it does have a serious side.
"A core part of our work here in Bristol involves using state-of-the-art climate models to simulate and understand the past climate of our Earth.
"By comparing our results to evidence of past climate change - for example, from tree rings, ice cores, and ancient fossils of plants and animals - we can validate the climate models, and gain confidence in the accuracy of their predictions of future climate."
The IPCC, which included scientists from the University of Bristol, used models to simulate climates from the last Ice Age to the "Ecocene greenhouse", 50 million years ago.
These models were then used to simulate the future climate of the planet.
The report has even been translated into Dwarvish and Elvish.
The Hobbit: The Desolation of Smaug premiered in Los Angeles on Monday and will be released in New Zealand on Thursday. Read the first reviews here.
- AAP and nzherald.co.nz