Physical observations of the North East Water (NEW) polynya, located near the north-eastern corner of Greenland, are presented. Data were collected in June 1991 by RV Polarstern. An idea is put forward to explain how the NEW is generated. A northward coastal current interacts with a persistent shelf ice barrier under which water can flow but that retains ice floes and therefore protects the NEW area from ice advection. Since in summer, the combination of currents, barrier and air-sea heat balance gives rise to a polynya. The distribution of upper water column vertical stability in the NEW is also influenced by its generation process. Surface melt water is retained by the shelf ice barrier, causing neutral vertical stability in its lee. Sea ice melting and land runoff then act as two distinct sources of vertical stability enabling the development of plankton blooms, especially in the northern part of the NEW. © 1994 Springer-Verlag.