The Earth’s magnetic field is rapidly decaying. Young earth creationists point out that the magnetic field was 40% stronger about a thousand years ago. Therefore, it would have been too strong to sustain life 20,000 years ago, so the earth must be younger than that. This theory was first introduced by Dr. Thomas Barnes who believed that Earth’s magnetic field decays at a rapid non-cyclic rate. Measuring of the strength of the magnetic field began in 1845, and since then, it has been decaying at a rate of 5% a century (Snelling 2012).
The magnetic field protects us from particles coming from the sun and directs them to the poles. In fact, this is what produces the Northern and Southern lights. If not for Earth’s magnetic field, life would cease to exist. Also, some animals that migrate rely on the magnetic field (Roach, 2004). The magnetic field extends into outer space, several thousands of kilometers above the earth.
The problem with the young earth creationists’ argument is that scientists have found that the magnetic field does geomagnetic reversals usuallyabout every few hundred thousand years and therefore it is self-sustaining. This is where the magnetic south and magnetic north are switched. For example, 800,000 years ago, a compass would have pointed South (Oregon State University, 2017). Evidence has been found on the sea floors to support this idea. Stripes of magnetism are alternating from north to south. These are referred to as “magnetic striping” (Magnetic Striping, 2014)
Creationists such as Dr. Russell Humphreys have argued that these reversals happened in rapid succession during and after the worldwide flood as described in the Bible. According to Humphreys, tectonic plates moving to the earth’s core would have caused the great flood in Genesis and this would cool the earth’s outer core. This cooling would cause magnetic field reversals over a short period of time. Humphreys believes that the magnetic field was growing in strength until the time of Christ and then it reversed (Humphreys, 1993).
However, that isn’t supported by what scientists have found, and much of the work of Barnes (and Humphreys work since it was based off Barnes) has been discredited. Barnes measured the strength of the magnetic field around 25 times. The model Barnes used was outdated, making his beliefs about the magnetic field invalid. Going by Gunst’s and McDonald’s data, Barnes didn’t use an appropriate measurement to measure the strength of Earth’s magnetic field (Mellem, 2005). He only looked at the dipole component of the magnetic field. The problem with this is that the magnetic field’s strength can remain the same, as the dipole field decays. The dipole field also seems to shift directions much more rapidly than the magnetic field which can be observed in rocks and ancient pottery (Matson 2017).
Then there is the dynamo theory which seems to be the most accepted theory regarding the magnetic field today. The earth’s core brings about the magnetic field. This is done by the hotter metals in the core rising while the cooler heavier metals settle on the core creating a convection current. The Coriolis effect is caused on the core due to the earth rotating on its axis. This causes the core to spin and cut through the previous magnetic field so a new one can be formed. Therefore, the magnetic field is a continued process that has lasted at least three billion years. (Rational Wiki, 2017)
In conclusion, the decaying magnetic field does not prove a young earth. The data used to prove a young earth by using the decaying magnetic field is outdated. Scientists have evidence that the magnetic field reverses every few hundred thousand years; therefore, the earth is probably about 4.5 billion years old as suggested.
Support for a Young Earth:
Support for an Old Earth:
Humphreys, D. R. The Earth’s Magnetic Field Is Young. Acts & Facts. 22. 1993 (8).
Matson, Dave. “Young-earth ‘proof’ #11: Since the earth’s magnetic field is decaying at an exponential rate, its strength would have been unrealistically high 25,000 years ago. Thus, Earth is less than 25,000 years old.” Retrieved 28 September 2017 from https://infidels.org/library/modern/dave_matson/young-earth/specific_arguments/magnetic_field.html
Mellem, Kevin. The Erosion of Continents as a Creation Clock. 2005. Retrieved from http://apps.usd.edu/esci/creation/age/content/creationist_clocks/magnetic_field.html
Oregon State University. “Earth’s magnetic field ‘simpler than we thought’.” ScienceDaily. ScienceDaily, 7 July 2017. www.sciencedaily.com/releases/2017/07/170707070517.htm
Rational Wiki – Retrieved on 29, September, 2017 from https://rationalwiki.org/wiki/Geomagnetism
Roach, John. The Earth’s Magnetic Field is Fading. National Geographic News. 2004, September 9th. Retrieved from http://news.nationalgeographic.com/news/2004/09/0909_040909_earthmagfield.html
Snelling, Dr. Andrew A. – #5 Rapidly Decaying Magnetic Field. Answers in Genesis. October 1st, 2012. Retrieved from https://answersingenesis.org/evidence-for-creation/5-rapidly-decaying-magnetic-field/