加拿大Pro-Oceanus 
加拿大Pro-Oceanus公司提供世界唯一的水下二氧化碳测量仪和总溶解气体压力仪。
Pro-Oceanus Systems Incorporated (PSI) was founded in 1998 driven by the need to measure dissolved gases in situ with a high level of accuracy and reliability. Founders, Dr. Bruce D. Johnson and Dr. Craig L. McNeil, developed the technology for the first PSI GTD-Pro, at a time when measurements of dissolved gases in the ocean were made by collecting water samples for later analysis in the laboratory. Meanwhile, sampling methods in the oceanographic community had shifted to moorings, platforms, and submersibles that often involved deployments of six months to a year without the opportunity for calibrations. According to Dr. Johnson, who was then the Executive Director of the Canadian Joint Global Ocean Flux Study, "some of the most important measurements for determining carbon uptake by the oceans weren't being made because the technology just didn't exist".