Could Hurricanes Spawn A Permanent El Niño?

An epoch of ancient time known as the early Pliocene 3–5 million years ago holds special fascination for climate scientists, because levels of carbon dioxide in the atmosphere were about as high as they are in modern climate.

What puzzles researchers is why, even though conditions such as sunlight, geography, and CO2 concentrations were much like today, Earth’s climate was different—temperatures were 7 degrees Fahrenheit warmer, there were no polar ice caps, sea level was 82 feet higher, and the Pacific Ocean was locked in a permanent El Niño.

(part of an article written by John Cox as was too long to post it all, but this is the “meat of the article”)

http://www.news.discovery.com/.../could-hurricanes-spawn-a-permanent-el-nio.html -

My first thought, how would scientists know the components of the atmosphere 3–5 millions years ago?

What are your thoughts on this hypothesis? It is an “educated guess,” is it not?