ASLR,
"
I imagine that folke_kelm must be pre-occupied doing something else today"
Indeed, i am occupied with other things most of my time, there are some small children and a job has to be done dealing with risk assessment and groundwater chemistry and some education too.
I am reading daily, but there is simply no time to write a comment, so please excuse me when i do not answer immediately.
I do not think that the discussion here has moved to some point of conclusion, at least not from my point of view. I still see some misconceptions about earthquakes, how they happen and why.
At first we have to distinguish between different geological phenomena cimate change is able to influence.
There are 1: slides 2: eruptions and 3: earthquakes.
All 3 may react to climate change in different ways. At first we have to consider about, what climate change possibly is able to change.
You ASLR; have provided us with a bunch of links, that give us an answer about this question.
Climate change is changing is rising the sea level, not equal but regional different, thus changing the vertical stress on plates, and human influence (not only climate change) is changing ground water level and again the vertical stress on plates. There is n discussion at all necessary about this fact.
Let us have a look at the consequences of this vertical stress change.
1: we begin with slides.
Here the limiting factor is internal cohesion (friction) inside the rock or sediment. This friction is strongly dependend of fluids in the free space between grains, in other words pore water pressure.
Increasing rain and rising ground water level will cause increasing pore water pressure and thus deminishing the internal friction, causing less shear stability of the rock. A slide may be the result as is seen frequently in California during El Nino years with increased rainfall.
2: Volcanism is always caused by vertical movement of hot mantle material or fluid rich partly melted masses from subducting in zones, where plates are recycled into the mantle (ring of fire) or in zones where crustal stretching takes place (mid ocean ridges).
In all cases we must take attention to the most important factor to generate liquid magma, pressure (static, not dynamic).
Liquid magma is, as i wrote earlier, generated when pressure is released, and only liquid magma is able to erupt.
The most important factor to release pressure is movement of plastic or fluid rich plastic mantle or crust material upwards in the crust. At a distinct pressure level the material will melt suddenly. this level is different for every material and every volcano.
You may translate pressure to a vertical stress, and now you see, that a melting ice cap, a melting glacier and if you want, draught and depleting of ground water will reduce pressure. IN the case of ice caps this will be at a rather high level.
But, please have in mind, that you must have material that is able to melt. Melting the ice cap has not caused any volcanic eruption anywhere in northern europe, it will not cause any eruption at the most places where we have ice caps today, simply because it will not move hot masses in the mantle. These movements take 10´s to 100´s of million years and they occure totally independend of any climate.
You see, a change in vertical stress can be caused by climate change. Let us now look at earthquakes. Here i disagree completely with the idea that climate change may cause an increase in frequency AND strength of earthquakes, let me explain why.
Nearly all earthquakes worth mentioning are caused by plate tectonics.
How does this work?
The different parts of the crust move independly over the more plastic deformed upper mantle. We know nowadays that the motor of this movement mostly is the pulling force of the subducting slab, not the pushing force of generating crust at mid oean ridges. This movement of plates create a nearly pure horizontal stress at places, where parts of crust with different velocities meet. These are mostly transform or strike-slip faults (it does not really matter which type).
The horizontal stress generates elastic strain at places where the two plates are locked.
The relation between plate movement and rising elastic strain is nearly linear.
If you consider the plate movement as constant (it nearly is), then you see, that the buildup of strain is a result of two variables, the plate velocity and the time of locked movement (no movement at a certain place). The longer the time the bigger the quake.
Is climate change in form of rising sea level or changing ground water level capable to increase horizontal stress? This is the only possibility to add energy to the system of locked elastic strain.
If a changing load is not providing horizontal stress, it may nevertheles influence the magnitude or the frequency of earthquakes, but in a different way.
If a vertical stress component breakes a lock (or increased fluid pressure in the shear zone), the strain will be released as earthquake BEFORE it will occure naturally, and so it will have a lesser magnitude.
The way plate tectonics work is only able to react with diminishing magnitude and higher frequency or, if you provide a stronger locking, with higher magnitude but fewer quakes.
Higher vertical stress due to changes in water level is not at all able to provide more energy to the system, it can only change the way this energy is released.
Earthquakes due to isostatic rebound from removing icecaps are entirely different. They will occure, but they will never have the same magnitude as quakes due to plate movement. The unloading will generate a new level of elastic strain which will be released at certain zones as moderate earthquakes until a new equilibrium is reached.