To those saying that mankind is not the main cause of the massive rise in global temperature, think again because scientists said that nature is not the one to blame for this century's recent cases of fatal heat waves.

According to Live Science, 14 of the 15 warmest years that have occurred between 2000 and 2015 can be attributed to human activity. In fact, the year 2015 was declared as the planet's hottest year, ever since Earth's temperature record keeping started in 1880.

Researchers found out that there are overwhelming evidence that suggest that these record-breaking temperature cannot occur just by natural climate variability alone.

As noted, the odds are between 1 in 10,000 and 1 in 170,000 that natural climate swings caused the high temperatures all around the globe. In addition, 2014's data alone said that there's a "one-in-a-million chance" that heat was caused by nature.

Stefan Rahmstorf, a professor from Potsdam Institute of Climate Impact and co-author of the study said, "The risk of heat extremes has been multiplied due to human greenhouse-gas emissions, as our data analysis shows."

In a related article by Wired, Rahmstorf added that although natural climate variations can't be explained, man-made global warming can.

He added the "anomalous warmth" has resulted into local heat waves all across the world, which caused thousands of deaths, lengthy droughts and wildfires.

To further prove their study, the researchers tested the effects of global warming and combined it with real-world climate data like the global and Northern Hemisphere temperatures using high-tech climate models.

In the study, the researchers' found out the difference between the natural phenomenon like the El Niño-caused ocean warming, from climate change due to human activities. Unfortunately, all cases of record-high temperatures all points out to mankind.

Last year, thousands of people in India died because of an extreme heat wave. In a report by CNN, India officials announced that 2,330 people have died.

In Pakistan's southern Sindh province, the death toll reached 800 people, with at least 780 souls perished in Karachi, with many of the victims are the elderly coming from low-income families.

These are just a couple of examples from last year's string of deadly heat waves that resulted into loss of lives. And if the latest research is any indication, Earth's temperature may rise even further.

And unless people makes a conscious effort to ease global warming, humanity will continue to keep on suffering the fatal consequences brought by man-made climate change.