April 30, 2024

Even in the Age of Satellites, 19th Century “Dinner Plate” Still Useful in Ocean Science

In the new study, a research study group including the University of Exeter, Plymouth Marine Laboratory, Vrije Universiteit (Netherlands) and the Italian Institute of Marine Sciences (ISMAR) compared the performance of Secchi disks with satellites and high-performance chromatography.
Secchi disks performed practically in addition to contemporary approaches at keeping an eye on phytoplankton abundance– suggesting Secchi measurements returning more than a century can help researchers comprehend long-term changes in the ocean.
” Phytoplankton produce half the worlds oxygen and form the base of ocean food webs, so monitoring them assists us track everything from climate change to the health of environments,” stated Dr. Bob Brewin, from the Centre for Geography and Environmental Science on Exeters Penryn Campus in Cornwall.
” New technology unquestionably provides us brand-new chances, but our research study reveals Secchi disks do a good job of estimating chlorophyll (a way of measuring phytoplankton abundance)– which suggests we must have the ability to integrate information from the past with modern measurements.
” This provides us a valuable source of long-term data on how our oceans are changing.”
Secchi disks are still used all around the world to keep track of ocean biomass and water quality, and co-author Dr. Jaime Pitarch, from ISMAR, stated the findings support their continued usage.
” Its a basic, low-cost tool, but our research study reveals its likewise incredibly effective,” he stated.
Scientists consisting of Dr. Brewin at Exeter, are working on a project that will utilize 3D-printed Secchi disks to monitor water quality in lakes in India and Africa, and coastal areas of the United States.
Prior to the 1850s, mariners utilized a variety of objects (in the same way as Secchi disks) to aid with navigation, including pans, cloths, and plates.
It was the Vatican astronomer Angelo Secchi, invited by the Papal Navy Commander Alessandro Cialdi to join a clinical cruise to study the murkiness of the sea in 1865, who standardized the method.
The paper, published in the journal Frontiers in Marine Science, is entitled: “Evaluating historical and modern optical methods for monitoring phytoplankton biomass in the Atlantic Ocean.”
Referral: “Evaluating modern and historical optical methods for monitoring phytoplankton biomass in the Atlantic Ocean” by Robert J. W. Brewin, Jaime Pitarch, Giorgio Dall Olmo, Hendrik J. van der Woerd, Junfang Lin, Xuerong Sun and Gavin H. Tilstone, 7 March 2023, Frontiers in Marine Science.DOI: 10.3389/ fmars.2023.1111416.
The measurements in the new study were collected on Atlantic Meridional Transect cruises. A UKRI Future Leader Fellowship funds Dr. Brewins work.

Secchi disks are lowered into the water to measure phytoplankton abundance. Credit: AMT
A basic 19th Century tool is still useful to ocean researchers in the age of satellites, brand-new research published in Frontiers in Marine Science shows.
A Secchi disk– traditionally called a “dinner plate” by sailors– is utilized outdoors ocean to determine concentrations of microscopic algae called phytoplankton.
It works by lowering the white disk into the water and recording the depth at which it disappears.