A CCM simulation of the breakup of the Antarctic polar vortex in the years 1980–2004 under the CCMVal scenarios

Abstract

. The CCM calculations are performed with the two ensemble members for REF1 scenario of the chemistry climate model validation (CCMVal) and the one ensemble member for the REF2 scenario. CCM simulates the development of the ozone hole from 1982 to 2000, as observed with a total ozone mapping spectrometer (TOMS), although the year-to-year variation is different from the observation owing to the internal variability of CCM and the ozone decreasing trends of CCM ozone in the two ensemble members of REF1 are underestimated. The trends in temperature and zonal mean zonal wind are analyzed and compared with the observations. There is consistency among the trends in zonal mean temperature, zonal mean zonal wind, and total ozone, but they differ among the ensemble members and observations. The diabatic heating rates and Eliassen-Palm flux fields are investigated in order to explain the differences. A delay trend in the breakup time of the Antarctic polar vortex is obtained for the period of 1980-1999 in the NCEP/ NCAR and ERA40 data. A similar trend is also obtained from the CCM simulations, with statistical significance in one ensemble member of REF1 and REF2. Because the trends of the observations in the EP flux from the troposphere and its deposition in the lower stratosphere are consistent with an advanced breakup date of the polar vortex and because the trends of the CCM simulations are very small, it is likely that the Antarctic ozone depletion had some effect on the delay during the period 1980 . From 2000, the NCEP/NCAR data show a large variation in breakup time, which makes the delay trend much less important. It is likely that the large variation in wave flux masked the effects of the ozone loss during that period. The two ensemble members of the REF1 simulation do not show such a dramatic change in the trend for the period 2000-2004, whereas REF2 shows a change in the trend for that period.

Diurnal ozone variations in the stratosphere revealed in observations from the Superconducting Submillimeter‐Wave Limb‐Emission Sounder (SMILES) on board the International Space Station (ISS)

“…[16] The MIROC3.2-CTM was developed at the National Institute for Environmental Studies (NIES), Japan, and incorporates the chemical module of CCSR/NIES CCM [Akiyoshi et al, 2009] into the MIROC3.2-GCM. The calculation was performed with horizontal winds nudged toward ERA-Interim reanalysis data [Dee et al, 2011].…”

Influence of lower stratospheric ozone variation on tropospheric temperature and mean meridional circulation in the Northern Hemisphere summer

“…[11] The model used in this study was based on the Center of Climate System Research/National Institute for Environmental Study (CCSR/NIES) atmospheric general circulation model (AGCM) [Akiyoshi et al, 2009] with T42 horizontal resolution and 34 vertical levels. To clarify changes in the dynamical fields due to changes in lower stratospheric ozone, we carried out a sensitivity experiment in which stratospheric ozone was increased by a certain factor over the mid-latitudes.…”

Global high-resolution simulations of tropospheric nitrogen dioxide using CHASER V4.0

“…In Sect. 6, we then discuss the implications of this evaluation and the po-REF-C1SD simulation using NIES CCM (Akiyoshi et al, 2009(Akiyoshi et al, , 2016Morgenstern et al, 2016). Dry and wet (rain out and washout) deposition is calculated based on the resistance-based parameterization (Wesely, 1989) and cumulus convection and large-scale condensation parameterizations, respectively.…”