A new study suggested that coal and unconventional fuel sources will do more harm to earth's climate than oilsands.

According to Andrew Weaver of the University of Victoria in Canada, earth's temperature will experience more dramatic spikes if man continues to burn coal and unconventional natural gas as against to using conventional fossil fuels.

Weaver and his colleague, Neil Swartz, claimed in their report, published on Sunday by the international science journal "Nature," that global warming will be further accelerated by indiscriminate usage of coal and natural gas.

Global temperature will rise by at least 15 degrees Celsius if all the coal reserves in the planet will be used up and another three degrees if all the natural gas deposits will be included in the package, Weaver's analysis showed.

But burning all the fossil fuel available now will not even kicked up the mercury by a whole degree, Weaver said.

The worst that such activities can do is to replicate at least 50 percent of the total temperature rise recorded by man since the last century, the new research showed.

"I was surprised by the results of our analysis ... I thought it was larger than it was," Weaver admitted, who had been previously commissioned by the United Nations to conduct two climate change probes.

"The conventional and unconventional oil is not the problem with global warming ... the problem is coal and unconventional natural gas," the scientist added.

But he clarified that the meat of his latest analysis is lay out the premise that as man becomes overly dependent on fossil fuel, natural gas and coal "we're less and less likely to wean ourselves away from them."

And in the process, limiting their role on man's daily activities would be become an impossible proposition, Weaver stressed.

It was an anomaly that man had been preoccupied in formulating ways that would limit the tapping of these non-renewable energy resource for fear that they would run out soon, Weaver said.

"We'll run out of human ability to live on the planet long before we run out of them ... (because) the problem is dependence on fossil fuels," Weaver asserted.