This is a multi-disciplinary research project that will take advantage of the Healy transiting the Northwest Passage from Alaska to Baffin Bay and collect underway data that will contribute to our understanding of the depth of the seafloor (bathymetry) and make measurements that will help us better understand climate change and changes in productivity in through the NWP and the Arctic. All measurements will be made while vessel is underway. No samples of the seafloor will be taken. Water and air samples will be taken by flow-through systems while the vessel is transiting. The ship will take advantage of the HEALY's transit from Alaska to Nuuk, to fill critical bathymetric gaps and add to the growing effort of complete seafloor mapping. We will make carbon isotope measurements through the NW Passage and in Baffin Bay to help better understand ocean-atmosphere-ice-land interactions using water and carbon (CO2 & CH4) isotope measurements of marine air and sea water. We will measure particulate organic matter distributions in surface waters across Northwest Passage- High resolution collection of suspended particulate samples through Healy’s surface underway seawater system along the ship’s track. We will collect gravity data across the Arctic Basin. We will look at net community productivity in surface waters across the Northwest Passage through sampling of Healy’s underway science seawater line for dissolved gases. The data will be used to calculate high-resolution rates of biological production rate (net community production) every ~2 minutes along the cruise track. We will collect Environmental DNA (eDNA) and do optical sampling in Arctic Seas and Northwest Passage to determine the community composition (eDNA), net community production of the mixed layer (PIGI), surface chlorophyll content for satellite intercomparison/calibration. A shipboard hydrographic/velocity survey will be carried out. The main objectives are to determine the fate of the fresh water carried into Baffin Bay by the West Greenland boundary current, and to establish the pathways by which heat from the current gets diverted to the Uummannaq region glaciers. The work has been, and will be, coordinated with scientists from the Geological Survey of Canada. Our colleagues from the GSC made initial community engagement visits in 2013. In May 2015 and in March 2016, community engagement sessions were held in Clyde River, Qikiqtarjuaq, Pangnirtung and Iqaluit. In 2018 and 2019, community consultations were held in Pangnirtung and Qikiqtarjuaq. COVID prevented such visits this year. Research results will be reported back during community visits about six months after the conclusion of the field season and will be made publicly available. Results will also be presented at workshops in the North, at science conferences and will result in publications in various scientific journals, reports and plain language documents over the months and years following the project.