TY - JOUR
T1 - Impact of Satellite Observations on Forecasting Sudden Stratospheric Warmings
AU - Noguchi, S.
AU - Kuroda, Y.
AU - Mukougawa, H.
AU - Mizuta, R.
AU - Kobayashi, C.
N1 - Funding Information:
This work was partly supported by Grants-in-Aid for Scientific Research (16J09665, 19K14798) from the Japan Society for the Promotion of Science. The JRA-55 family data sets are available on the JMA Data Dissemination System (http://jra.kishou.go.jp/JRA-55/index_en.html) and collaborative organizations (detailed information is available on the JRA-55 website). The numerical data used in this study are available (https://doi.org/10.5281/zenodo.3538978). The GFD-DENNOU Library was used for graphics. We thank two anonymous reviewers for their constructive comments.
Publisher Copyright:
©2020. The Authors.
PY - 2020/3/16
Y1 - 2020/3/16
N2 - The observational impacts of satellite data assimilation on extended-range forecasts of sudden stratospheric warmings (SSWs) are investigated by conducting ensemble forecast experiments. We use two Japanese novel reanalysis products: the Japanese 55-year reanalysis (JRA-55) and its subset that assimilates conventional observations only (JRA-55C). A comparative examination on the reproducibility for SSWs between the two ensemble forecasts reveals that the impact of satellite observations is significant for forecasts starting 5 days before the SSW onset, with 20% less accuracy in the JRA-55C forecasts. Moreover, some of forecasts of vortex-splitting SSWs show a sudden appearance of deep difference, which lasts over a few months in the lower stratosphere and significantly affects the surface climate. These results highlight an important role of mesospheric and upper stratospheric circulations on the onset and development of SSWs.
AB - The observational impacts of satellite data assimilation on extended-range forecasts of sudden stratospheric warmings (SSWs) are investigated by conducting ensemble forecast experiments. We use two Japanese novel reanalysis products: the Japanese 55-year reanalysis (JRA-55) and its subset that assimilates conventional observations only (JRA-55C). A comparative examination on the reproducibility for SSWs between the two ensemble forecasts reveals that the impact of satellite observations is significant for forecasts starting 5 days before the SSW onset, with 20% less accuracy in the JRA-55C forecasts. Moreover, some of forecasts of vortex-splitting SSWs show a sudden appearance of deep difference, which lasts over a few months in the lower stratosphere and significantly affects the surface climate. These results highlight an important role of mesospheric and upper stratospheric circulations on the onset and development of SSWs.
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U2 - 10.1029/2019GL086233
DO - 10.1029/2019GL086233
M3 - Article
AN - SCOPUS:85081716522
SN - 0094-8276
VL - 47
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 5
M1 - e2019GL086233
ER -