Sequoia’s Laser In Situ Scattering and Transmissometry (LISST) particle size analyzers have significantly advanced the understanding of flocculation in aquatic environments. Since the mid-1990s, LISSTs have often replaced or supplemented older technologies with in-situ and real-time measurements of...
In 2019 Sequoia published a short note on our website regarding the feasibility of measuring plastic particles in situ. Two main conclusions were drawn: If one considers the number concentration of plastic particles (α), and the sampling volume (SV) of any instrument used for measuring plastic particles,...
The University of Hawai’i at Manoa (UH) operates the Hyper-bb hyperspectral backscatter instrument. Professor Angelicque White uses the instrument as a component of the open ocean Hawai’i Ocean Time-series (HOT) program to collect key datasets related to calibration and validation of scattering...
Kelly Thomas, Biological Oceanographer A longtime user of LISST instruments, the University of Alaska Fairbanks has been using the new, LISST-200X-style 4,000m rated LISST-Deep from Sequoia Scientific, Inc. The LISST-Deep instrument measures in-situ particle size distribution from 1 um to 500 um, optical...
Sequoia Scientific LISST Instruments in Benguela Upwelling System In May of 2022 the French research vessel Tara sailed northward along the Western coast of Africa as part of the multi-year Microbiomes mission. Several instruments from Sequoia Scientific were installed on Tara during transit between...
Bubbles in water are studied intensively. For modeling and measurement purposes it is sometimes assumed that bubbles are spherical, but this is only true up to a certain size: When the hydrostatic pressure difference from top to bottom of the bubble is larger than the internal pressure inside the bubble...
…Wherein we’ll learn about the LISST-Tau and some of the ongoing developments at Sequoia. (Part XIII can be found here https://www.sequoiasci.com/article/the-history-of-sequoia-part-xiii/ ) In the fall of 2019 Sequoia got the opportunity to develop a dedicated transmissometer. While the laser-diffraction...
…Wherein we’ll learn about the LISST-AOBS, Hyper-bb and LISST-Horizon. (Part XII can be found here: https://www.sequoiasci.com/article/the-history-of-sequoia-part-xii/ ) After the LISST-ABS introduction in 2016, Yogi noted that the LISST-ABS and turbidity sensors have opposite-trending changing sensitivities...
…Wherein we’ll learn about the LISST-ABS and the LISST-200X (Part XI can be found here: https://www.sequoiasci.com/article/the-history-of-sequoia-part-xi/) In 2013 Yogi came up with an idea for a point sensor for measuring suspended sediment concentration; the LISST-ABS. It was developed in collaboration...
…Wherein we’ll learn about the LISST-VSF and some arriving and departing employees. (Part X can be found here: https://www.sequoiasci.com/article/the-history-of-sequoia-part-x/ ) The LISST-VSF In 2011, Sequoia finished an SBIR (Small Business Innovation Research grant) and developed a full-angle...