Dissolved gases in the deep North Atlantic track ocean ventilation processes by Seltzer, AM, Nicholson, DP, Smethie, WM, Tyne, RL, Le Roy, E, Stanley, RHR, Stute, M, Barry, PH, McPaul, K, Davidson, PW, Chang, BX, Rafter, PA, Lethaby, P, Johnson, RJ, Khatiwala, S, Jenkins, WJ