New article on Greenland air temperature variability

Former NERSC director Sebastian H. Mernild co-authored an article in the International Journal of Climatorlogy, titled “The role of blocking circulation and emerging open water feedbacks on Greenland cold‐season air temperature variability over the last century”.

 

Sebastian H. Mernild: Photo: NERSCSebastian H. Mernild: Photo: NERSC

Greenland is subject to many climate studies, and the majority of these focus on factors affecting the summer melting season. On the other hand, only a few studies have focused on regional climatic changes outside the summer season.

Sebastian H. Mernild describes what makes this new study special: “This study is unique, because relatively little work has been carried out to assess regional climatic changes in other seasons. Here, we focus on the less studied cold season (i.e., autumn and winter) climate. Most studies have focused on the melting and summer seasons, but here the focus was on winter and autumn conditions.

He and his colleagues studied the variability of the air temperature in Greenland between 1873 and 2013. They investigated air temperature observations from coastal regions and air temperature model data from outlet glaciers and analyzed how the air temperature is connected to several factors. Those factors are sea ice in the North Atlantic, the temperature at the sea surface, and atmospheric circulation indices for the region.

This study is important since our findings imply that large-scale tropospheric circulation has a strong control on surface temperature over Greenland through dynamic and thermodynamic impacts”, says Sebastian H. Mernild. He and his co-authors found that Greenland’s air temperatures in autumn and winter are connected to atmospheric processes over the North Atlantic and Greenland – the North Atlantic Oscillation and atmospheric blocking occurring over Greenland defined by the Greenland Blocking Index.  

 

Reference:

Ballinger, T.J., Hanna, E., Hall, R.J., Carr, J.R., Brasher, S., Osterberg, E.C., Cappelen, J., Tedesco, M., Ding, Q., and S.H. Mernild, 2020: The role of blocking circulation and emerging open water feedbacks on Greenland cold‐season air temperature variability over the last century. International Journal of Climatology. 1-23. https://doi.org/10.1002/joc.6879