Recent Trends in Arctic Sea Ice and the Evolving Role of Atmospheric Circulation Forcing, 1979–2007 - Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications - page 21

Plate 8. Monthly SLP (contours, hPa) and SIC (color shading, percent) anomaly maps for May through October 200.
The contour interval is 1 hPa; with negative values are dashed, and the zero and positive values are solid. Anomalies are
defined relative to the 1979-2007 long-term monthly means.