| Popis: |
In 2010, the Northern Hemisphere, in particular Russia and Japan, experienced an abnormally hot summer characterized by record-breaking warm temperatures and associated with a strongly positive Arctic Oscillation （AO）, that is, low pressure in the Arctic and high pressure in the midlatitudes. In contrast, the AO index the previous winter and spring （2009/2010） was record-breaking negative. The AO polarity reversal that began in summer 2010 can explain the abnormally hot summer. The AO-related summertime tropical oceanic warm temperature anomaly might have been a remote cause of the formation of blocking highs in the Europe, thus amplifying the positive summertime AO. Understanding of this interseasonal linkage may aid in the long-term prediction of such abnormal summer events. |
