Forecast Study of the Cold December of 2005 in Japan: Role of Rossby Waves and Tropical Convection

DOI Web Site Web Site 被引用文献4件 参考文献27件
  • INABA Morio
    Climate Research Department, Meteorological Research Institute
  • KODERA Kunihiko
    Climate Research Department, Meteorological Research Institute The Solar-Terrestrial Environment Laboratory, Nagoya University

この論文をさがす

抄録

Japan experienced unusually heavy snowfall and low temperatures in December 2005 owing to the cold air advected from Siberia. As a result of this strong and sustained cold surge, record-breaking snowfalls occurred repeatedly along the coast of the Sea of Japan. To determine the cause and to examine the accuracy of numerical forecasts of such unusual weather as well as to investigate the impact of initial and boundary conditions on the forecasts, we conducted one-month ensemble forecasts for December 2005 by changing lower boundary conditions, such as sea-surface temperature (SST) and sea-ice coverage (SIC). Forecasts were initiated every day between November 1 and December 1 to investigate their dependency on initial atmospheric conditions. Our results showed that SST and SIC appeared to have little impact on the forecasts of a cold December in Japan. Instead, high sensitivity to initial atmospheric conditions was found. Almost all forecasts initiated before November 16, 2005 failed to reproduce the cold December; however, those initiated after that date successfully predicted it.<br>By comparing the differences between successful and unsuccessful members for predicting the cold December, we identified the processes producing the cold December of 2005. In the successful forecasts, we found that blocking developed over the North Atlantic in mid-November 2005. When it decayed, the emitted Rossby waves propagated along the subpolar jet across Siberia, inducing a cold surge over Japan. Moreover, the Rossby waves propagating over the Indian sector along the subtropical jet gave rise to intense convection over the Bay of Bengal and the South China Sea, which led to the deepening of a low-pressure trough over Japan. The unusual weather conditions in December have been due to the simultaneous occurrence of these two processes.

収録刊行物

  • 気象集誌. 第2輯

    気象集誌. 第2輯 88 (4), 719-735, 2010

    公益社団法人 日本気象学会

被引用文献 (4)*注記

もっと見る

参考文献 (27)*注記

もっと見る

関連プロジェクト

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ