Salt vs fresh water: how does salinity affect sea conditions?

Salt vs fresh water: how does salinity affect sea conditions?

Today we’ll walk about an interesting but obscure topic for most land dwellers: how stormy sea conditions can vary between large bodies of fresh and salt water, like the Great Lakes and the Pacific Ocean. It’s not something we usually think about on land, but mariners know it well. And a bit more about what local conditions make our region so hazardous.

A foggy time on the lower Columbia River

A foggy time on the lower Columbia River

It’s been pretty foggy in parts of the lower Columbia region the past few days. Or not foggy at all, depending on where you are. It’s part of a a larger pattern this week statewide of dense foggy conditions.

We’ll talk about what might be causing our fog here and what ships do under such conditions.

The USNS Grasp, a Military Sealift Command rescue and salvage ship, comes to Portland

The USNS Grasp, a Military Sealift Command rescue and salvage ship, comes to Portland

We’re seeing unusual ships arriving in the river this week so far. Yesterday it was the USCGC Healy, the Coast Guard’s biggest ship, headed to the Swan Island shipyard.

Today it’s the USNS Grasp, a highly specialized rescue and salvage ship, whose job it is to save people and ships when they get in trouble on the water.

Image: the USNS Grasp, photo courtesy of US Navy photo gallery.