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U.S. Geological Survey (USGS) scientist Lisa Robbins is aboard the research vessel (R/V) Atlantis in the Davis Strait near the Arctic Circle. The cruise, a collaborative effort between U.S. and Canadian scientists, runs from September 4–26, 2015, and is led by Craig Lee, a Senior Principal Oceanographer at the University of Washington's Applied Physics Laboratory. This cruise is part of the Go-Ship Program, which has been deploying and retrieving physical oceanographic instrumentation and collecting chemical oceanographic data in the select areas since 2003.

The cruise focuses on the Davis Strait, which connects the North Atlantic and the Arctic Ocean through the Canadian Arctic Archipelago and Baffin Bay. Currents through the archipelago are integrated at the strait, making it an ideal location to observe the interaction between the Arctic Ocean and the North Atlantic. The rapidly changing polar environment—including melting sea ice, surface warming, enhanced transport of warm water from the south, and Greenland ice-sheet melt—can influence air-sea carbon dioxide (CO₂) flux, nutrient cycles, and ocean acidification, providing an opportunity to collect data critical for understanding climate change.

Robbins and Jonathan Wynn (University of South Florida–USF) will collect both discrete seawater samples and data acquired underway from water in the ship's "uncontaminated seawater system," which takes in seawater and delivers it to different laboratories on the ship. Discrete samples will be collected, preserved, and sealed for later analysis of total alkalinity, total carbon, and dissolved organic carbon. Surface seawater will be analyzed onboard for oxygen and carbon isotopes, partial pressure of CO₂ (pCO₂), and pH. Three different instruments will be used to measure pH: a SeaFET Ocean pH Sensor, a spectrophotometer, and a new handheld pH photometer recently developed by USGS and USF and funded by a USGS Innovations grant. The cruise is the first field test of the handheld pH photometer, and its measurements will be compared to those obtained from the other instruments. Atmospheric CO₂ will be monitored throughout the cruise using a real-time trace gas monitor capable of measuring gases at concentrations of parts per billion.

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Canadian scientists from the Bedford Institute of Oceanography will collect data "on station" (while the ship is stopped), including samples for analysis of dissolved inorganic carbon and alkalinity, pCO₂ and methane, oxygen, nutrients, transient tracers (sulfur hexafluoride [SF6] and dichlorodifluoromethane [CFC-12]), and oxygen isotopes. They will also collect underway pCO2 measurements and phytoplankton and zooplankton information.

Robbins and Wynn will compare data collected during the 2015 cruise to carbonate chemistry data collected previously from Arctic cruises (2010–2012) in higher latitudes. These comparisons will be used to understand ocean acidification and carbon fluxes in the Arctic and sub-Arctic.