In the absence of aggressive government policies aimed at curbing greenhouse gas emissions, a number of leading organizations, including the United Nations, the World Bank and others, have begun issuing analyses that regard potentially dangerous temperature elevations as not just a possibility should the status quo prevail, but a near certainty even if things start to change.

The latest report, released Wednesday by the United Nations Environment Program, suggested that greenhouse gas emissions levels are currently around 14 percent above where they need to be by the end of the decade in order to avoid what many analysts believe could be a risky level of planetary warming.

That report comes on the heels of a study issued Tuesday by the Geneva-based World Meteorological Organization, which stated that human civilization has pumped roughly 375 billion tonnes, or metric tons, of carbon dioxide into the atmosphere since the dawn of the industrial age, when the extraction and combustion of fossil fuels began in earnest.

"These billions of tonnes of additional carbon dioxide in our atmosphere will remain there for centuries, causing our planet to warm further and impacting on all aspects of life on earth," said WMO Secretary-General Michel Jarraud, in a statement issued Tuesday. "Future emissions will only compound the situation."

On Sunday, the World Bank issued a report suggesting that the climate could warm a full 4 degrees by the end of the century -- less than 90 years from now -- even if countries fulfill the modest emissions-reduction pledges they've already made.

A 4-degree uptick in temperatures is significantly higher than what has long been deemed the maximum amount -- 2 degrees Celsius, or 3.6 degrees Fahrenheit -- that average global temperatures could rise while still maintaining a climate similar to that in which human civilization has evolved.