Tides and Currents in Portsmouth Harbor

[mhabich]

The tricky currents in the Piscataqua have long vexed mariners, including those of NSPN https://www.nspn.org/forum/topic/7814-tides-and-currents/

In 1929, the US Coast and Geodetic Survey issued a study
 savable PDF ftp://ftp.library.noaa.gov/docs.lib/htdocs/rescue/cgs_specpubs/QB275U35no1501929.pdf (link broken as of July 2022)
 Google Books, better scan but not savable https://babel.hathitrust.org/cgi/pt?id=uc1.$b72168;view=1up;seq=37
in paperback at https://www.amazon.com/currents-Portsmouth-harbor-Geodetic-Survey/dp/B008248T6S

It describes instrumented measurements, variations with moon phase and orbit, effect of barometric pressure, stationary vs progressive wave, fresh water flowing above salt water, reversing currents within the river and rotary currents outside...  If you could do without the equations, the current diagrams on pp 51-62 can stand alone.  The appendix has as good a description of the causes of tides as I've seen.

The breakwaters and dredging done by the Corps of Engineers http://www.nae.usace.army.mil/Missions/Civil-Works/Navigation/New-Hampshire/Portsmouth/ have changed the area since 1929.

A instrumented study from 2007 is described in a slideshow at https://www.des.nh.gov/organization/divisions/water/wmb/coastal/ocean_policy/documents/070927_te_presentation_kammerer.pdf (link broken as of July 2022)