This is the primary script, initial conditions, and boundary layer SST for an article going to be submitted to AMS JC, named “Another look at asymmetry in the connection between ENSO and the NAO”. We conducted atmospheric modeling experiments using the European Center-Hamburg Model version 5.4 (ECHAM-5.4, Roeckner et al. 2003) from the Max-Plank Institute. The ECHAM5.4 was run with 1.875 lon*1.875lat horizontal spacing, 19 vertical levels from the surface to 10 hPa. In the control experiment (CTL), 1955-2009 monthly historical SST and SIC were used as the lower boundary condition and run for 55 years, including a 4-year spin-up. To reduce the potential impact of ENSO and NAO signals, 20 weak or neutral ENSO and NAO years (the normalized Niño-3.4 and NAO indices are between -0.7 and 0.7) were selected, including 1958, 1960, 1961, 1966, 1967, 1969, 1974, 1977, 1979, 1980, 1981, 1985, 1987, 1990, 1996, 2000, 2001, 2003, 2004, and 2006. To examine the influence of different types of ENSO on the NAO, we further performed nine sensitivity experiments covering only the period from December 1st to February 28th in the 20 sample years. The sensitivity-minus-CTL differences represent the atmospheric response to the SST anomalies in the different ENSO winters.
The numerical result dataset is too large to
archive, we provided the initial conditions for 20 sample years and the
boundary layer conditions for the different sensitivity experiments. The folder
contains the boundary layer condition for each sensitivity experiment is named after
the experiment name. The initial conditions begin with "rerun".