The possibility of gravitational influence on the likelihood of an earthquake occurring when the sun and moon are in certain alignments relative to earth could make a valid hypothesis worth investigating, and the answer no doubt resides in the current scientific literature or not.
I imagine the answer is that statistically the probability of an earthquake occurring at a certain time in the lunar cycle is the same as the chance of an earth quake occurring at any time.
An earthquake occurs due to the stresses between rock layers being greater than the friction between the layers. The direction of movement, and therefore stresses involved and their direction will vary on the type of fault. That is a normal fault involving relative downward movement, thrust or reverse fault with upward movement and a strike-slip with sideways movement.
The stress vectors of these faults will be in different directions depending on the type of fault and their orientation. Gravity is also a vector quantity with a direction, and would have to line up with the fault's stress vectors if the aforementioned hypothesis is to be correct.
Given that gravity would have the same affect on both layers of rock, presuming similar rock densities, that is the moon or sun would 'pull' on the rock layer that was pushing, and pull on the rock layer that was pulling (relatively speaking), any gravitational affects would negate each other and have no influence on the outcome.
As for global warming, the fact that previous generations had to endure lengthy droughts and so forth is irrelevant, as are the solar cycles which may have short repeating cyclical influences.
The data empirically shows that the average background temperature of the planet has increased and accelerated since the start of the industrial revolution. We ignore this data at our and the generations to come, peril.
If you wish to argue with the temperature data fine, then consider the acidification of the world's oceans which has increased by 30%, due to the increased CO2 from the atmosphere dissolving in the oceans as a carboxylic acid.
Many marine creatures now find it difficult to form their calcite shells due to the acidity. We risk killing off marine life and turning the oceans into a dead stinking acid bath if we fail to reduce our CO2 emissions.
