74% of Climate Change is Manmade

SN#1 via Flickr/CC BY 2.0

Yep, it's our fault the planet is warming up, despite the myriad naysayers who have devoted heaps of their time to insisting otherwise. Those naysayers, who buck the vast scientific consensus, are likely part of the inspiration that lead a duo of scientists to double-check whether human activity had the largest impact on global warming. They've published their results, which, unsurprisingly, register an unambiguous 'affirmative' in the journal Nature Geoscience.

The paper's abstract notes that (emphasis mine) "Natural climate variability is extremely unlikely to have contributed more than about one-quarter of the temperature rise observed in the past 60 years." Indeed, "Most of the observed warming — at least 74 % — is almost certainly due to human activity."

Imagine that! Our power plants, factories, and cars, which have emitted an exponential amount of carbon pollution (along with a number of other heat-trapping greenhouse gases) since the Industrial Revolution, have actually changed the earth's climate! The ever-rising concentration of carbon dioxide in the atmosphere (we're at around 392 parts per million about now) has done exactly what the scientists predicted it would do.

After all, the idea that CO2 traps heat is about the least controversial scientific concept this side of inertia. Nonetheless, many have argued that the sensitivity by which our climate reacts to an ever-increasing concentration of CO2 is not as great as the scientific consensus maintains. Others famously argue that the earth's heating up is due to 'natural causes'. And thus, an experiment to put both charges to rest was carried out. See the Nature Geoscience paper for all the details, but here's the gist, from the abstract:

Since 1950, the average global surface air temperature has increased by more than 0.5 °C. To separate human and natural causes of warming, the researchers analysed changes in the balance of heat energy entering and leaving Earth — a new ‘attribution' method for understanding the physical causes of climate change.

Greenhouse gases such as carbon dioxide have contributed around 0.85 °C to global warming since the 1950s, Swiss researchers have found. Their findings, which are strikingly similar to results produced by other attribution methods, provide an alternative line of evidence that greenhouse gases, and in particular carbon dioxide, are by far the main culprit of recent global warming.

Yes, it's even more evidence that man is having a significant impact on the world's climate system. Those who continue to dispute the scientific consensus on climate change are truly running out of ground to stand upon.

Tags: Global Climate Change | Global Warming Causes | Global Warming Science


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