If the Ice Caps melted, how much longer would each day be?

Question

If Earth's polar ice caps fully melted and the water returned to the oceans, the oceans would be deeper by about 30 m. What effect would this have on Earth's rotation?

Make an estimate of the resulting change in the length of the day. (Concern has been expressed that warming the atmosphere resulting from industrial pollution could cause the ice caps to melt.)

Would you use any formulas to solve this? Can you show your work? I happen to know the answer is the days would be longer by about 0.8 s. Good Luck!

Answer 1

I'll assume it is your typical physics problem, which states some highly simplified conditions to demonstrate some physics principal and not a real engineering or natural science problem. We will assume the Earth increases its radius by 30 meters without any change in total mass, and that the Earth is a sphere of uniform density. In that case, the rotation rate would be proportional to the change in the moment of inertia of the Earth, I. For a uniform sphere I=2/5MR^2. You need to calculate the existing I and the new I after the radius change. Since M does not change, and we want only the ratio of the two Is, we can ignore the 2/5M and just compare radius. The radius of the Earth is about 6,370km or 6,370,000 meters. Adding 30 meters makes it 6,370,030 meters and the ratio of 6,730,030^2/6,730,000^2 is about 1.00001. That is about a 0.001% change, and about 0.001% of 24 hours is about 0.8 seconds.

As an angular momentum problem it is neat, but as a real life Earth problem it is totally bogus. There are all sorts of complications, like the sea only covers 70% of the Earth, the density of water is less than the average density of the Earth, the ice that melted started out far above sea level in many cases, and so on.

Answer 2

i wager they don't coach about the ice a lengthy time period the earth has had in college anymore. The ice a lengthy time period handed off 1000's years in the past. formerly automobiles and something that guy may have produced to reason the ice a lengthy time period, the subsequent international warming inbetween the ice a lengthy time period. there's a study that got here out a pair month in the past from Germany that announces that forests produce extra greenhouse gases than what people do. Then there are study that say the solar has impact on warming the earth. I said a deal on the heritage Channel about a volcano in 1815 that a lot ash replaced into despatched into the air it brought about replaced into said as the three hundred and sixty 5 days without summer season. contained in the 1970s they were anxious about international cooling. Now they're anxious about international warming? both idea which could be brought about by way individuals is ludicris. Even those espouse international warming say we are able to not give up it. this idea that international warming is responsible for all storms is a touch bizzare because there allways has been hurricans, volcanoes, and tornadoes. Even this week it replaced into determined that the Artics were honestly tropical at one aspect.

Answer 3

Another effect would be the impact of increased tidal activity. The rotation of the earth is gradually slowing due to tidal friction caused largely by the orbit of the moon around the earth. It is also causing the moon's orbit to decay slightly. Don't have the equations handy to predict the size of the effect, but you could probably Google additional info.