Creationists don't want their readers to be distracted with problems like that -- unless the cat is already out of the bag and something has to be said.
When the dipole moment is strong, carbon-14 production is suppressed below normal; when it is weak, carbon-14 production is boosted above normal.
What the magnetic field does is to partially shield the earth from cosmic rays which produce carbon-14 high in the atmosphere.
To that end, he quoted some authorities, including Richard Lingenfelter.
Having accomplished that, Morris concluded that the barrel was still in the process of being filled up and that, given the present rate of water coming in and leaking out, the filling process began only 10,000 years ago.
This nullifies the carbon-14 method as well as demonstrating that the earth is less than 10,000 years old. One suspects that the scientific world would not be using the carbon-14 method if it were so obviously flawed.
Could it be that the whole scientific community has missed this point, or is it another case of creationist daydreaming?
Now, the fuller that barrel gets the more water is going to leak out the thoroughly perforated sides, just as more carbon-14 will decay if you have more of it around.
Finally, when the water reaches a certain level in the barrel, the amount of water going into the barrel is equal to the amount leaking out the perforated sides.
We say that the input and output of water is in equilibrium.