Recent Intensified Winter Coldness in the Mid-High Latitudes of Eurasia and Its Relationship with Daily Extreme Low Temperature Variability

Figure 6

Composite difference between high and low ECI years (±0.5 SD) from 1979 to 2013 for the SLP (shaded) and 925 hPa wind field (vector) in ((a) the units are hPa for SLP, m·s⁻¹ for 925 hPa wind) the zonal temperature advection ((b) unit: Kday⁻¹), the meridional temperature advection ((c) unit: Kday⁻¹), and the total horizontal temperature advection ((d) unit: Kday⁻¹). The dotted areas and wind vectors indicate a significant difference that exceeds 0.05 for the two-tailed Student’s -test.

(a) SLP and UV925

(b) Zonal Tadv

(c) Meridional Tadv

(d) Total Tadv