What role do natural forces play in the current global warming trend?

Answer 1

Natural forces play no significant role in the current global warming.

The three most prominent natural factors are solar output, volcanic eruptions and out gassing, and vegetation.

For the past thirty years solar output has slightly declined, but not enough to detect any measurable climate effect. The particulate spewed by volcanoes tends to temporarily lower earth's albedo, reflecting more sunlight, and the hydrogen sulfide gas vented also lowers the temperature. CO2 emitted by volcanoes will, over extended periods of time, counteract this. Currently humans release more than 100 times as much CO2 as all earth's volcanoes combined.

Vegetation can sequester carbon, which is how the vast deposits of coal and oil formed, hundreds of millions of years ago. Fifty million years ago a plant called Azolla, which grew in warm Arctic regions pulled about 40% of the CO2 out of the atmosphere, causing earth's temperature to fall over a span of just a few million years.

None of these natural forces, of course, play a significant role in the current global warming trend, which is primarily driven by anthropogenic (human caused) oxidation of fossil carbon.

_________________________________________________________________

Answer:

No scientist would disagree that without natural global warming we would be unable to exist on this planet. The past 11,000 years have seen a fairly steady warming trend totaling about 11 degrees C. Approximately 10 degrees of this warming has occurred before man started burning coal. The past 150 years has seen another degree of warming. Science experts all agree that a portion of this degree of warming is also natural. Many science experts, including many climate experts do believe that man is responsible for a portion of this one degree of additional warming. Some even are willing to say that man may be responsible for most of this one degree of warming. The bottom line though is that the overall warming trend of the planet would be impossible without natural forces such as the sun. Nature is the dominant factor here in every conceivable measurement, including emission of green house gases. Nature produces 99.7% while man produces less then 0.3%. All warming is due to our very naturally occurring sun. Without nature, there would be zero warming.