Meanwhile, human-caused climate change and melting ice-caps has now changed the length of an Earth day due to the relocation and redistribution of the Earth's mass:
The researchers added that missing piece of information to their calculations, along with the latest tide gauge and satellite data about the amount of sea-level rise and post-glacial rebound. They found glacier melt due to climate change since the industrial revolution has caused the Earth to slow down exactly as they had predicted.
How much? Don't expect too much extra time on your hands — researchers predict that a century from now, Earth's slower rotation will make each day 1.7 milliseconds longer.
http://www.cbc.ca/news/technology/sea-level-earth-rotation-1.3361446
I don't need 'faith' to understand rotational mass and inertial moments to compute things like this, I simply need an understanding of basic math and physics.