The NOAA has just released a new report on the historic drought that has been affecting California for the last three years. Stunningly, investigators are saying that human-driven climate change is not to blame, and it is instead the consequence of natural phenomena.

That comes as a big surprise, even for experts, as the ongoing drought was recently revealed to be the worst the region has seen in more than a millennium, with 2014's summer being the driest seen in a whopping 1,200 years.

So far this December has been one of the wettest the region has ever seen during a drought, only adding to suspicion that this uncharacteristic and extreme weather could only be caused by man's interference with the natural way of things.

However, according to Richard Seager, lead author of the new NOAA report, the drought is actually just a very extreme example of a natural pattern.

"It's important to note that California's drought, while extreme, is not an uncommon occurrence," he said in a recent statement. "In fact, multi-year droughts appear regularly in the state's climate record, and it's a safe bet that a similar event will happen again. Thus, preparedness is key."

The report, aptly named "Causes and Predictability of the 2011 to 2012 California Drought," builds on earlier measurements of California climate factors, looking especially to the region's winters, which provide most of the groundwater for the remainder of any given year. (Scroll to read on...)

For the last three years, unpredictable atmospheric circulation, combined with La Niña, formed high-pressure systems in winter months over the West Coast, blocking storms from the Pacific that would have brought rain to California's thirsty land.

Researchers note that minor climate factors may have exacerbated this effect, but the underlaying cause was completely natural - just difficult to predict.

Even more interesting, this current pattern doesn't reflect climate change models at all. In fact, Seager told Mother Jones that most models actually indicate that as global warming presses in on the Northern Hemisphere, a good deal of California should start seeing more low-pressure systems and heavy winter storms. Only, spring precipitation, the NOAA says, is predicted to decrease.

"There is immense value in examining the causes of this drought from multiple scientific viewpoints," said Marty Hoerling, report co-author and researcher with the NOAA's Earth System Research Laboratory.

He added that scientists are still a long way away from being able to more accurately predict these droughts, but being able to identify human or natural causes is certainly a start.

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).