How does the global warming affect seismic activities?

Maybe but I think your perspective is not broad enough.

It would be like imagining that the earth was a flat bed simi truck trailer. The ice on the poles were just a few crates. Sure moving the crates around on the trailer would cause a little bit of bending and twisting within the trailer itself, it is hardly significant to really do much. But why? Because the trailer is already supporting the weight of the crates and thus already has their weight distributed over itself. Sure the moving around would cause pressure changes but it is so little that virtually nothing changes. In other words the plates of the planet are so thick and the ice is relatively "light" compared to the plates that them moving around is not even "noticed" by the plates.

Ohh I just saw a documentary, It said that antarticas ice is so thick and heavy that it made a depression (cant remember how deep but it was significant) in the earths crust.

Seismic activity is subterranean. Ice can do plenty to the features of the earth's crust, but way ice effects the land is by scrapping, not compressing.

A
R
T

If memory serves, that isn't entirely true. If we think about tectonic plates as a balancing board, if one end is weighed down by ice, the other end will rise. As ice bodies melt, the plate balances back, which is the reason Britain is slowly sinking.

What?

A
R
T

New England was covered by 3 Km of ice during the Illinoian and Wisconsin Glaciation. After this ice retreated, the land began rebounding from compressional stresses. Its still rebounding. We have several geologic formations near the Maine shore called the "Presumpscott Formations" which, by their patterns of deposition, we can see that the sea/land contact is actually lowering based upon rebound. There are chunkas of the Presumpscott where one can see whale fossils high up in sediments on a cliffside, and these whale fossils are recent (less than 10000 years)

Remember , theres about 30 million km of ice in the planet and about 20million km of which s in contact with the ground (this is the amount that is NOT floating pack Ice). If all that ice were to just decouple, or float away, or dissolve, the oceans would rise (HOW MANY FEET?)

I read that the weight of water behind three gorges dam is expected to have a miniscule effect on the earths rotation. I would expect the redistribution of the weight of antarctic ice to have some similar effect. As fm has stated, the weight of ice has affected areas such as maine and the great lakes before.

It is possible, with new issostatic forces due to climate change that the microseisms and crustal dynamics can change, More earthquakes in areas where ice is removed, vulcanism ditto. We have to wait and see. Many of these predictions have failed in the "modelling" because most models are not iterative enough to take and process newest data and microlevel data.

FM - Interesting about the whale fossils/bones in raised areas. The theory is that the land itself is rising and not due to plate collision?

I thought that the effect glaciers had on the earth in cases like the great lakes and in places like Maine was that they carved the earth and that's what caused areas of depression.

A
R
T

Wow strongest earthquake in 100 years.

If you could calculate the rate of rise and decent of the plates as the weight is shifted from melting Ice. Couldn't it help in the prediction of earthquakes?

"Big data" programs mesure everything about earthquake epicenters, hypocenters, ranges and eccentricity, and compare these to almost anything we can think of including moon stages and precip.
Earthquakes have many causes and associations, location of an earthquake wrt a plate boundary is only one.

Oh good I was hoping someone was taking in account the weight of the rising seas and the melting of ice