Over the last 250 years, the average global temperature has increased approximately 1.5 degrees Celsius. This average incremental increase in temperature corresponds almost exactly to the increase in atmospheric carbon dioxide, the primary greenhouse gas of concern, because it is emitted on such a huge scale by modern industrial civilization.
To put this in what is perhaps an unfortunate perspective, the planet-wide impact of human-caused global warming is estimated to be the equivalent of detonating about 400,000 Hiroshima-sized atomic bombs each day or 4.6 atomic bombs per second.
That heat has to go somewhere, and scientists don’t fully understand how the earth is dealing with all the extra heat. Global temperature will continue to increase if nothing is done — but it’s hard to predict how bad or what the consequences will be.
The key is not the problem but the solutions — none of the ones being proposed currently have any realistic chance of succeeding.
Despite 40 years of concerted effort, conventional clean energy technologies, while making impressive gains, do not yet have the capacity or efficiency to fully address global warming and energy needs worldwide.
In the United States, renewable energy sources account for 11.09% of U.S. energy consumption. Half of the renewables include biomass (organic) (5.5%) which is not emissions free. The remainder is made up of hydroelectric (2.83%), wind (1.98%), solar (.48%), and geothermal (.25%).
Under the best case scenario, solar would add 1% capacity per year and is still expensive at around 21 cents per kilowatt-hour. Though falling, its cost far exceeds that of natural gas which has a cost of around 5.7 cents per kilowatt hour.