slideshow 1 slideshow 2 slideshow 3 slideshow 4 slideshow 5 slideshow 6

You are here

FAQ - Global Warming

1. Could the reason for polar ice cap melting be caused more by the change in the Earth’s axis rather than global warming/greenhouse gases?

While earthquakes and major volcanoes can make small shifts in the pole of the Earth relative to the crust of the Earth, the pole has two long-term motions: 1) a circular one called the Chandler wobble which is a circular motion of about 9 meters (20 feet) and a period of about 433 days and 2) a drift toward the west, which has totaled about 29 meters since 1900. Most of this drift is a result of global warming, not a cause! There has been a redistribution of mass as the Greenland ice sheet has melted and been redistributed in the oceans.

At the same time the axis of the Earth is moving relative to the stars. There is a 25,800-year precession of the axis of the Earth. While Polaris is now our pole star, in 13,000 years, it will be Vega. This effect is fairly small and long-term. We are closest to the Sun in January, but in 13,000 years we will be closest to the Sun in July, so our winters may be a little colder and our summers a little warmer. There is also a smaller motion of the Earth’s axis called nutation. This 18.6-year motion is due to the precession of the Moon's orbit with this period. Both of these are due to the gravitational pull of the other planets and the Sun on the Earth and Moon.

2. How much does volcanic degassing affect global warming and climate change?

Gasses such as H2O, SO2, CO2, H2S, HCl are emitted from volcanoes. Of these, H2O and CO2 are important greenhouse gases and can contribute to global warming. However, SO2 can block out the Sun and create global cooling.

PSI, a Nonprofit Corporation 501(c)(3), and an Equal Opportunity/M/F/Vet/Disabled/Affirmative Action Employer.
Corporate Headquarters: 1700 East Fort Lowell, Suite 106 * Tucson, AZ 85719-2395 * 520-622-6300 * FAX: 520-622-8060
Copyright © 2017 . All Rights Reserved.