Fig. 3: Mean sea level pressure (MSLP) bias (hPa) as an ensemble mean
over the 5 historical realizations for 1985–2014 compared to ERA5
climatology (Copernicus Climate Change Service (C3S), 2017; Hersbach et
al., 2020) from 1985–2014. (a) DJF, (b) MAM, (c) JJA, (d) SON, (e)
annual mean
Fig. 4 shows zonal means of temperature and zonal wind biases averaged
over the period 1985-2014. In large areas of the troposphere,
temperature biases are smaller than 1 °C. Exceptions are the high
latitudes with larger positive biases in the north and larger negative
biases in the south. Furthermore, in the mid- and high-latitudes there
are negative temperature biases of up to around 3 °C in the lower
stratosphere around 200 hPa. Not surprisingly, the bias pattern looks
very similar to the one from MPIM shown in Müller et al. (2018), their
Fig. 9e. The zonal mean zonal wind is generally well represented
compared to the ERA5 reanalysis data. Biases are mostly smaller than 2
m/s. Exceptions are the tropical stratosphere, the tropical upper
troposphere and the subtropical / mid-latitude stratosphere around 100
hPa and 40-50°N and S. Compared to Müller et al. (2018), their Fig. 9d,
biases are generally similar although the subtropical / mid-latitude
stratosphere areas of strong biases of more than 2 m/s are smaller in
AWI-CM. Furthermore, the negative bias around 60°S extending from 700 to
200 hPa in Müller et al. (2018) does not exist in AWI-CM.
(a) (b)