Seismic? No way! This year we have had a trough of low pressure sitting over us for a few weeks. It is this that has been causing the horrible high humidity. It does not take much imagination to realise that water does not find its own level if one end of the Med is under a low pressure and the other end under a high pressure. The latter will push the water towards the low pressure, so the water level will be unusually high round this island.
Now, the low pressure has some other effects. It will exacerbate the effect of those convection cells called sea breezes. As the land heats more rapidly than the sea, after mid-morning, this will heat the air which will become less dense and rise. As Nature abhors a vacuum, cooler air will rush in from the sea, causing the sea to become agitated. This is why the coastal towns are cooler and more humid in summer, compared to inland. If the synoptic wind is in the same direction as the sea breeze, then the effect can be quite violent: we have had a number of days when the synoptic wind has been easterly. When this happens, water is pushed into the Bay of Larnaca, causing the level to rise even farther (the total level may be as high as ~10-15 cm above average; this doesn't sound much, but it is enough to cause the effects you have seen).
So your "problem" is due to weather, nothing more nor less.
If you are interested, I have recently added a page explaining the weather where we are (
http://www.cypenv.org/wxfcast/explanations.htm) as an addition to my weather forecasts but this is more specific to 20 km inland from Larnaca. However, it will give you a general idea.
I have broken three records in late July since I started measuring the weather at this location over 2 years ago (+ one in early July!):
Max temperature 42.4 °C 28.7.2007
Highest heat index 48.2 °C 31.7.2007
Min humidity 7% 9.7.2007
Min pressure 997.9 hPa 30.7.2007