The Role of Rossby-Wave Propagation in a North American Extreme Cold Event

Figure 3

Daily geopotential height (contours; gpm) and its anomaly (shading; gpm) at 10 hPa in January 2014 relative to the 30-year climatology. The 30-year climatology refers to the 30-year average of January in 1981–2010. Contour interval: 240 gpm.

(a) 10 hPa

(b) 10 hPa

(c) 10 hPa

(d) 10 hPa

(e) 10 hPa