Some interesting points in this guest post by Robert W. Endlich:
Sea level changes over relatively recent geologic and human history demonstrate that alarmist claims do not withstand scrutiny. Sea levels rose significantly after the last ice age, fell during the Little Ice Age, and have been rising again since the LIA ended around 1850. In fact, Roman Empire and Medieval port cities are now miles from the Mediterranean, because sea levels actually fell during the Little Ice Age.
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Those rising oceans created new ports for Greek and Roman naval and trade vessels. But today many of those structures and ruins are inland, out in the open, making them popular tourist destinations. How did that happen? The Little Ice Age once again turned substantial ocean water into ice, lowering sea levels, and leaving former ports stranded. Not enough ice has melted since 1850 to make them harbors again.
The ancient city of Ephesus was an important port city and commercial hub from the Bronze Age to the Minoan Warm period, and continuing through the Roman Empire. An historic map shows its location right on the sea. But today, in modern-day Turkey, Ephesus is 5 km from the Mediterranean. Some historians erroneously claim “river silting” caused the change, but the real “culprit” was sea level change.
Ruins of the old Roman port Ostia Antica, are extremely well preserved – with intact frescoes, maps and plans. Maps from the time show the port located at the mouth of the Tiber River, where it emptied into the Tyrrhenian Sea. The Battle of Ostia in 849, depicted in a painting attributed to Raphael, shows sea level high enough for warships to assemble at the mouth of the Tiber. However, today this modern-day tourist destination is two miles up-river from the mouth of the Tiber. Sea level was significantly higher in the Roman Warm Period than today.
An important turning point in British history occurred in 1066, when William the Conqueror defeated King Harold II at the Battle of Hastings. Less well-known is that, when William landed, he occupied an old Roman fort now known as Pevensey Castle, which at the time was located on a small island in a harbor on England’s south coast. A draw bridge connected it to the mainland. Pevensey is infamous because unfortunate prisoners were thrown into this “Sea Gate,” so that their bodies would be washed away by the tide. Pevensey Castle is now a mile from the coast – further proof of a much higher sea level fewer than 1000 years ago.