What is Sea Breeze

The extraordinary high specific heat of water—it warms slowly—stands in contrast to the quite low specific heat of soil, especially dry soil, which warms up fast on a clear day.
Along a coastline, of course, this temperature difference means a pressure difference: cool, dense, high-pressure air over the water and warm, low-pressure air over land.
A pressure gradient sets the air in motion.
A sea breeze pushes inland.
Water's high specific heat also means that, once warm, it is slow to cool.
Wind sometimes blow offshore at night, as the land loses daytime heat faster than the water.
This is why it really is cooler at the shore.