Computer modelling has shown that such a high pressure region can originate from the motions of the gas at the edge of a gas hole — just like the one found in this disc. (sciencedaily.com)
Update: This article has been updated to clarify that El Niño forces a high pressure anomaly into a persistent low pressure region over the Amundsen sea. (earther.com)
However, in July the sea level pressure (SLP) pattern shifted back to a more typical low pressure region over the central Arctic Ocean (Figure 3), causing ice divergence that has significantly slowed ice loss during the first two weeks of July (Figure 2). (searcharcticscience.org)