The Complete Idiot's Guide to 2012 - Dr. Synthia Andrews Nd [95]
One thing is for sure: things like holes in the ozone layer and the weakening of the magnetic field are allowing dangerous levels of UV light and electromagnetic energy to enter the atmosphere, contributing to global warming. Are these natural cycles run amok or are they part of a larger picture we are unaware of?
Solar Cycles
When solar flares burst out from the sun, electromagnetic radiation explodes along the magnetic pathways of the Van Allen Belts. As the solar maximum of 2012 approaches and you start to see the amazing Northern Lights farther and farther south, keep in mind the amount of energy being pushed along these pathways.
There is no question that the solar cycle of 2012 will add energy and therefore heat into the earth’s environment. We can certainly look forward to a significant impact on global climate as flares increase, but does that explain global warming over the past 100 years, or the incredible leap in warming over the past 10 years?
Cosmic Caution
The best available evidence indicates that the estimated 3 to 7 degrees change in temperature projected over the next century will be unprecedented.
Some scientists think that radiation from the sun has caused global warming, but not on its own. Not because solar activity has increased but because the earth’s magnetic field has decreased, letting electromagnetic radiation from the sun enter the earth’s atmosphere. Let’s have a look at the impact of anomalies in the magnetic field.
Magnetic Field Anomalies
As we discussed in Chapter 10, the earth’s magnetic field has been slowly weakening, letting in more electromagnetic radiation, or solar plasma. At the same time, scientists are finding a hole in the magnetic field over the South Atlantic Ocean called the South Atlantic Anomaly.
The question is, are these really new phenomena? We have only been measuring the earth’s magnetic field for 150 years and only with high-tech satellites since the 1960s. Although the magnified fossil record has provided details of 3.2 billion years, we don’t really know whether fluxes in the field are part of a natural cycle. Some suggest both the hole and the weakening of the field are homeostatic mechanisms meant to keep balance on the planet. In that case, why would the planet itself be pushing such an extreme envelope?
The Role of Volcanoes
If you’ve thought about volcanoes and global warming, you might have assumed that because volcanoes produce heat they increase global warming. It’s counterintuitive, but many people think volcanoes are part of the cooling mechanisms of the planet. Land-based volcanoes put more than heat into the atmosphere. They also spew out a lot of particles, gases, and other debris. Rising on air currents to the upper atmosphere, the debris acts like the ozone layer and deflects the sun’s radiation, helping to cool the planet. Many people think that as global warming gets worse, more and more volcanoes will erupt to counteract the heating effect.
Cosmic Caution
Volcanoes that are located under the sea directly add to the heat of the oceans. Because they don’t spew debris into the air, they don’t add the cooling impact of “nuclear winter.”
Earth Cycles
Another added effect in the heating and cooling of the planet is our position in space. The earth’s orbit isn’t a circle but an oval, meaning that at certain times we’re closer to the sun and other times farther away. In addition, the shape of the oval changes, going through its own 100,000-year cycle called the Milankovitch cycle. In the following figure, orbit B is the path the earth takes in the more circular part of the Milankovitch cycle, and orbit A is the path the earth takes in the most oval part of the cycle. This means that at the most oval shape there are even greater differences between how