Surface-based temperature inversions in Alaska from a climate perspective

Surface-based inversions in Fairbanks occur 82 % and 68 % of the days in January and February, respectively.

“SBIs in Fairbanks occur 82 % and 68 % of the days in January and February, respectively (Bourne et al., 2010).”

Fairbanks experiences some of the strongest and longest-lasting surface-based inversions in urban areas due to its location about 800 km from the coast and bowl-shaped local topography that partly shields the city from synoptic winds and favors accumulation of cold air at the bottom.

“Located about 800 km from the coast, with a”

If the prevailing synoptic weather situation results in weak pressure gradients and low wind speeds, the very small turbulent heat flux cannot balance the surface energy loss, resulting in cooling of the surface and the development of a surface-based inversion and stable boundary layer.

“If the prevailing synoptic weather situation results in weak pressure gradients and hence low wind speeds, the very small turbulent heat flux cannot balance the surface energy loss, resulting in a cooling of the surface and the development of a surface-based inversion (SBI) and SBL (Bourne et al., 2010;Mahrt, 1999;Serreze et al., 1992;Stull, 1988).”

Stronger SBIs typically have a higher depth.

“Furthermore, as indicated in Bourne et al. (2010), stronger SBIs typically have a higher depth.”

Previous studies show that the SBI depth over Fairbanks in January and February is typically of a few hundred meters.

“These results are in agreement with previous studies that show that the SBI depth over Fairbanks in January and February is typically of a few hundred meters (Bourne et al., 2010), which is much higher than the observed h mix , which is limited by the lack of turbulence.”