Characteristics and Development Mechanisms of Northeast Cold Vortices

Figure 8

Composite anomaly fields of 300 hPa zonal wind (unit: m·s⁻¹) for NCVs in (a) May to September, (b) late spring, and (c) early autumn, and for MCVs in (d) May to September and (e) summer. The solid and dashed contours indicate positive and negative anomalies of zonal wind speeds, respectively. Areas with grey color are those reaching the 95% significance test.