Data for "Strong linkage of El Niño-Southern Oscillation to the polar cold air mass in the Northern Hemisphere"

This repository archives the codes for analysis and plot presented in a manuscript submitted to GRL: "Strong linkage of El Niño-Southern Oscillation to the polar cold air mass in the Northern Hemisphere". The codes are written in GrADS, Octave, and NCL format. 

The repository also contains a Fortran package for isentropic polar cold air mass diagnosis as in Iwasaki et al. (2014). The package is specifically created by Dr. Y. Kanno.

Reference:

Iwasaki, T., Shoji, T., Kanno, Y., Sawada, M., Ujiie, M., & Takaya, K. (2014). Isentropic Analysis of Polar Cold Airmass Streams in the Northern Hemispheric Winter. Journal of the Atmospheric Sciences, 71(6), 2230–2243. https://doi.org/10.1175/JAS-D-13-058.1