90. 梅雨前線帯の季節進行と西風ジェット
1 JANUARY 2010 SAMPE AND XIE 119
FIG. 4. Sea level pressure (solid lines at every 2 hPa) and GPCP precipitation (mm day21, shading) for (a) 16 May–14 Jun, (b) 15 Jun–
14 Jul, and (c) 15 Jul–13 Aug; (d)–(f) 500-hPa geopotential height (solid lines at every 30 m) and mean wind speed (m s21, shading). In
(d)–(f) the period is shifted by one day.
with heating, which in turn induces a couplet of a low- a. Thermodynamic balance
level trough and upper-level ridge. To avoid this com-
plication by the convective feedback, we investigate the Following Rodwell and Hoskins (2001), we consider
91. 上昇域と斜面の形
122 上昇域 JOURNAL OF CLIMATE 斜面の形 VOLUME 23
上
下
上
下
FIG. 7. Horizontal advection of temperature (black lines at every 0.2 K day21; negative contours are dashed and zero lines omitted) and
upward vertical pressure velocity (Pa s21, shading) at 500 hPa for (a) 17 May–15 Jun and (c) 16 Jul–14 Aug. (b),(d) As in (a),(c) but for
500-hPa mean horizontal wind (arrows) and its speed (solid lines at every 4 m s21) with 500-hPa temperature (8C, shading).
underlying SST and convective instability decrease, the warm advection along the meiyu-baiu rainband. North
weakening the diabatic enhancement of upward motion. of the Tibetan Plateau, by contrast, the 500-hPa jet runs
The correlation of interannual variability of the ratio southeastward, leading to cold advection over northern
of convective to total precipitation with surface tem- China. The cold advection corresponds to air parcels
92. 実験してみよう！
ある一つの対流による中層加熱だけから，
他の要素が無くても本当に西風ジェットが上昇できるか？
128 JOURNAL OF CLIMATE VOLUME 23
