C AdvT 1000200 hPa diff

Figure 7. Differences between surface albedo Rs = 0.15 and Rs = 0.25 (control run) for (a) July precipitation and winds at 850 hPa (from CN03), (b) the upper tropospheric temperature (from CN03), (c) horizontal advection of temperature — {v • VT) and (d) horizontal advection of moisture — {v • Vq).

Figure 7. Differences between surface albedo Rs = 0.15 and Rs = 0.25 (control run) for (a) July precipitation and winds at 850 hPa (from CN03), (b) the upper tropospheric temperature (from CN03), (c) horizontal advection of temperature — {v • VT) and (d) horizontal advection of moisture — {v • Vq).

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Figure 7. (Continued)

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Figure 7. (Continued)

Tibetan Plateau. This warming associated with the uplift of the Tibetan Plateau enhances the cyclonic monsoon circulation over the Asian continent and induces the westward extent of the Pacific subtropical high. This low-level wind anomaly pattern is similar to the surface albedo experiments in Fig. 7(a). However, the anomalous cyclonic monsoon circulation [Fig. 8(a)] is much stronger and more concentrated than that in Fig. 7(a). The anomalous monsoon circulation did not reach as far west as in the surface albedo experiments. This is due to the more concentrated warm tropos-pheric temperature anomalies. The anomalous monsoon circulation enhances the precipitation over the eastern part of the Asian continent, and reduces the precipitation over the western part of the Asian continent via the IRH mechanism [Figs. 8(c) and 8(d)]. The ventilation effect also suppresses convection over the western part of the Asian continent [Figs. 8(c) and 8(d)]. The westward extent of the subtropical high transports dry air from the Pacific to reduce the precipitation over the southeastern part of the Asian continent and the neighboring oceans, including the South China Sea and the western North Pacific [Fig. 8(d)]. Comparing both the advection terms of temperature and moisture, — (v • Vq) is more important than — (v • VT). The term —(v • Vq) is also responsible for inducing the dipole pattern of the rainfall anomalies over the east coast of the Asia continent (Fig. 8), since their patterns are very similar over this region.

5.3.2. Ocean heat transport

To examine the effects of ocean heat transport, zonally symmetric Q flux anomalies are prescribed with a maximum anomaly at the equator. These Q flux anomalies induce roughly symmetric SST anomalies with maximum negative SST anomalies at the equator [Fig. 9(a)]. The cold SST anomalies create colder tropos-pheric temperature with maximum anomalies at the equator [Fig. 9(b)]. These cold tro-pospheric temperature anomalies increase the meridional gradient of the tropospheric temperature globally, so the responses to the enhanced meridional temperature gradient cover entire continental areas including Eurasia and Africa. Figure 9(c) shows that positive precipitation anomalies extend from East Asia southwestward to Africa. This long positive precipitation anomaly band indicates a northward extent of the monsoon rain zones from Asian to Africa. The corresponding anomalous cyclonic circulation is not only over Eurasia and Africa but also extends farther westward into the Atlantic. The easterly trade winds at lower

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