Residents enjoy a night out on the seawall, illuminated by candlelight, during an event to promote 'Earth Hour' organized by WWF Peru, in Barranco's Lima district, February 26, 2014. 'Earth Hour' is a symbolic blackout held around
Residents enjoy a night out on the seawall, illuminated by candlelight, during an event to promote 'Earth Hour' organized by WWF Peru, in Barranco's Lima district, February 26, 2014. 'Earth Hour' is a symbolic blackout held around the world, seeking to raise awareness of global climate change, according to the organisers. This year's event will be held on March 29. REUTERS/Mariana Bazo REUTERS/Mariana Bazo

To the world nowadays, the terms global warming and climate change are parallel to food shortage, illnesses, infestation, resource competition, terrorism, soaring temperatures and possibly death of the human race and planet Earth. But did you know that it was climate change that helped Genghis Khan to conquer and take over Asia? Rain was his foremost ally.

According to a study released Monday in the Proceedings of the National Academy of Sciences, the rainfall and mild temperatures that occurred from 1211 to 1225 made the land fertile and helped feed the small groups of travelling herds of Genghis Khan and his sons and grandsons.

Central Asia that time was found to be usually cold and arid.

The favourable weather conditions enabled grasslands to thrive, helping the Mongols build up large numbers of horses and livestock to support their world domination campaign.

"Where it's arid, unusual moisture creates unusual plant productivity, and that translates into horsepower," Amy Hessl, physical geographer of West Virginia University, said. "Genghis was literally able to ride that wave."

Sampling tree rings in the gnarled and twisted Siberian pines in the Hangay Mountains in central Mongolia, Neil Pederson of Columbia University's Lamont-Doherty Earth Observatory said they saw a straight 15-year period of above-average moisture. "It falls during an important period in Mongol history and is singular in terms of persistently wet conditions."

"The transition from extreme drought to extreme moisture strongly suggests that climate played a role in human events," Ms Hessl told National Geographic.

Though of course it wasn't the only thing, Genghis Khan is known as a brilliant tactician, the weather conditions during his reign "must have created the ideal conditions for a charismatic leader to emerge out of the chaos, develop an army, and concentrate power. Where it's arid, unusual moisture creates unusual plant productivity, and that translates into horsepower-literally. Genghis was able ride that wave."

Genghis Khan, at the time of his death in 1227, had founded an empire that covered Korea, China, Russia, the Middle East, Eastern Europe, Persia, India, and Southeast Asia.

Could it happen again? That climate change aids a future conqueror to dominate the world?

"Future warming may overwhelm increases in precipitation, leading to similar heat droughts, with potentially severe consequences for modern Mongolia," the authors said.

"Though we cannot attribute a single event to climate change, warming temperatures have stacked the deck toward (more evaporation), so even if the amount of precipitation remains the same, high temperatures will generate a more intense drought," Ms Hessl said.

"That's what we observed in the early 21st century, and based on past moisture variation in Mongolia and future predictions of warming, we would expect to see similar events in the future."