naa a22 4500 510753531 CHVBK 20180411083113.0 cr unu---uuuuu 180411e20130101xx s 000 0 eng 10.1007/s13131-013-0265-9 doi (NATIONALLICENCE)springer-10.1007/s13131-013-0265-9 Two climate factors in May that affect Korean rainfall in September [Elektronische Daten] [Ki-Seon Choi, Il-Ju Moon] This study revealed a high positive correlation between rainfall in Korea during September and the trade wind (TW)/Arctic Oscillation (AO) index in May that combines two climate factors, low-level TWs and the AO. This correlation was identified on the basis of the difference in the 850 h Pa streamline analysis between the positive and negative phases selected using the combined TW/AO index. In May, the spatial pattern of the anomalous pressure systems is similar to that in the positive AO phase. These anomalous pressure systems continue in June to August (JJA) and September, but the overall spatial distribution shifts a little to the south. Particularly in September, a huge anomalous anticyclone centered over the southeast seas of Japan strengthens inmost of the western north Pacific region and supplies a large volume of warm and humid air to the region near Korea. This characteristic is confirmed by the facts that during the positive TW/AO phase, the subtropical western north Pacific high (SWNPH) is more developed to the north and that the continuous positioning of the upper troposphere jet over Korea from May to September strengthens the anomalous upward flow, bringing warm and humid air to all layers. These factors contribute to increasing September rainfall in Korea during the positive TW/AO phase. Because the SWNPH develops more to the north in the positive phase, tropical cyclones tend to make landfall in Korea frequently, which also plays a positive role in increasing September rainfall in Korea. The above features are also reflected by the differences in average rainfall between the six years that had the highest May Niño 3.4 indices (El Niño phase) and the six years that had the lowest May Niño 3.4 indices (La Niña phase). The Chinese Society of Oceanography and Springer-Verlag Berlin Heidelberg, 2013 anomalous pressure nationallicence Arctic Oscillation nationallicence Korea nationallicence low-level trade wind nationallicence rainfall nationallicence tropical cyclone nationallicence Choi Ki-Seon National Typhoon Center, Korea Meteorological Administration, 699-942, Seogwipo, Republic of Korea aut Moon Il-Ju College of Ocean Science/Ocean and Environment Research Institute, Jeju National University, 690-756, Jeju, Republic of Korea aut Acta Oceanologica Sinica The Chinese Society of Oceanography 32/1(2013-01-01), 32-47 0253-505X 32:1<32 2013 32 13131 https://doi.org/10.1007/s13131-013-0265-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s13131-013-0265-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Choi Ki-Seon National Typhoon Center, Korea Meteorological Administration, 699-942, Seogwipo, Republic of Korea aut NATIONALLICENCE 700 1- Moon Il-Ju College of Ocean Science/Ocean and Environment Research Institute, Jeju National University, 690-756, Jeju, Republic of Korea aut NATIONALLICENCE 773 0- Acta Oceanologica Sinica The Chinese Society of Oceanography 32/1(2013-01-01), 32-47 0253-505X 32:1<32 2013 32 13131 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer