Interannual variability of the spring atmospheric heat source over the Tibetan Plateau forced by the North Atlantic SSTA

Abstract The temperature shift over the eastern flank of the Tibetan Plateau is examined using the last 50 yr of Chinese surface station observations. It was found that a strong cooling shift occurs in early spring (March and April) and late summer (July, August, and September) in contrast to the warming shift in other seasons. The cause of the March–April (MA) cooling is investigated in this study. The MA cooling shift on the lee side of the Tibetan Plateau is found to be not a local phenomenon, but rather it is associated with an eastward extension of a cooling signal originating from North Africa that is related to the North Atlantic Oscillation (NAO) in the previous winter. The midtropospheric westerlies over the North Atlantic and North Africa tend to intensify during positive NAO phases. The enhanced westerlies, after passing over the Tibetan Plateau, result in strengthened ascending motion against the lee side of the plateau, which favors the formation of midlevel stratiform clouds. The increased amount of stratus clouds induces a negative net cloud–radiative forcing, which thereby cools the surface air and triggers a positive cloud–temperature feedback. In this way, the cooling signal from the upstream could “jump” over the Tibetan Plateau and leave a footprint on its lee side. The continental stratiform cloud–climate feedback plays a significant role in the amplification of the cooling shift downstream of the Tibetan Plateau.

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Effect of the atmospheric heat source on the development and eastward movement of the Tibetan Plateau vortices

Tellus A Dynamic Meteorology and Oceanography ◽

10.3402/tellusa.v66.24451 ◽

2014 ◽

Vol 66 (1) ◽

pp. 24451 ◽

Cited By ~ 24

Author(s):

Lun Li ◽

Renhe Zhang ◽

Min Wen ◽

Liangke Liu

Keyword(s):

Tibetan Plateau ◽

Heat Source ◽

The Tibetan Plateau ◽

Atmospheric Heat Source ◽

Atmospheric Heat ◽

Tibetan Plateau Vortices

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Interannual Variation of Summer Atmospheric Heat Source over the Tibetan Plateau and the Role of Convection around the Western Maritime Continent

Journal of Climate ◽

10.1175/jcli-d-15-0181.1 ◽

2015 ◽

Vol 29 (1) ◽

pp. 121-138 ◽

Cited By ~ 23

Author(s):

Xingwen Jiang ◽

Yueqing Li ◽

Song Yang ◽

Kun Yang ◽

Junwen Chen

Keyword(s):

Water Vapor ◽

Tibetan Plateau ◽

Heat Source ◽

Interannual Variation ◽

The Tibetan Plateau ◽

The South ◽

Maritime Continent ◽

Southern Boundary ◽

Atmospheric Heat Source ◽

Atmospheric Heat

Abstract The impacts of summer atmospheric heat source over the Tibetan Plateau (TP) on regional climate variation have attracted extensive attention. However, few studies have focused on possible causes of the interannual variation of atmospheric heat source over the TP. Total heat (TH) is generally composed of three components: surface sensible heat, latent heat release of condensation (LH), and radiative convergence. In this study, it is found that interannual variation of summer TH is dominated by LH in the central and eastern TP. The atmospheric circulation patterns associated with the TH over the TP in June are different from those in July and August. Large TH is accompanied by a cyclone centered over the South China Sea in June, which is replaced by an anticyclone in July and August. The interannual variation of July–August TH over the central and eastern TP is significantly affected by convection around the western Maritime Continent (WMC) that modulates the LH over the southeastern TP. Enhanced WMC convection induces an anticyclone to the south of the TP, which favors water vapor transport to the southeastern TP and thus an increase in precipitation. Enhanced convection over the southeastern TP may exert a positive feedback on local precipitation through pumping more water vapor from the southern boundary. Both observations and model simulations indicate that the enhanced WMC convection can induce the anticyclone to the south of the TP and convection–circulation is important for maintenance of the anticyclone.

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Portraying the Impact of the Tibetan Plateau on Global Climate

Journal of Climate ◽

10.1175/jcli-d-18-0734.1 ◽

2020 ◽

Vol 33 (9) ◽

pp. 3565-3583 ◽

Cited By ~ 2

Author(s):

Haijun Yang ◽

Xingchen Shen ◽

Jie Yao ◽

Qin Wen

Keyword(s):

Tibetan Plateau ◽

North Atlantic ◽

Thermohaline Circulation ◽

Global Climate ◽

Tropical Pacific ◽

The Tibetan Plateau ◽

The North ◽

The North Atlantic ◽

The Impact ◽

The Tropical Pacific

AbstractAs the most extensive highland in the world, the Tibetan Plateau (TP) plays an important role in shaping the global climate. Quantifying the effect of the TP on global climate is the first step for a full understanding of the TP’s standing on planet Earth. Through coupled model sensitivity experiments, we draw a panorama of the TP’s global impact in this paper. Our model results show that the absence of the TP would result in a 4°C colder and 10% drier climate in the Northern Hemisphere (NH). The TP has a striking remote effect on the North Atlantic. Removing the TP would enhance the westerlies in the mid- to high latitudes of the NH and weaken the easterlies over the tropical Pacific. More moisture would be relocated from the tropical Pacific to the North Atlantic, shutting down the Atlantic thermohaline circulation, which would eventually result in more than 15°C colder and 20% drier climate over the North Atlantic. Our model results suggest that the presence of the TP may have contributed greatly to the hospitable modern climate in the NH, by promoting the establishment of the thermohaline circulation in the Atlantic, and therefore enhancing the northward ocean heat transport and atmosphere moisture transport across the equator.

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The AMV phase-dependence of the connection between February NAO and March surface air temperature over the Tibetan Plateau

10.5194/egusphere-egu21-9879 ◽

2021 ◽

Author(s):

Jingyi Li ◽

Fei Li ◽

Shengping He ◽

Huijun Wang ◽

Yvan J Orsolini

Keyword(s):

Tibetan Plateau ◽

Air Temperature ◽

Rossby Wave ◽

North Atlantic ◽

Wave Train ◽

Surface Air Temperature ◽

The Tibetan Plateau ◽

The North ◽

Rossby Wave Train ◽

The North Atlantic

<p>The Tibetan Plateau (TP), referred to as the &#8220;Asian water tower&#8221;, contains one of the largest land ice masses on Earth. The local glacier shrinkage and frozen-water storage are strongly affected by variations in surface air temperature over the TP (TPSAT), especially in springtime. This study reveals a distinct out-of-phase connection between the February North Atlantic Oscillation (NAO) and March TPSAT, which is non-stationary and regulated by the warm phase of the Atlantic Multidecadal Variability (AMV+). The results show that during the AMV+, the negative phase of the NAO persists from February to March, and is accompanied by a quasi-stationary Rossby wave train trapped along a northward-shifted subtropical westerly jet stream across Eurasia, inducing an anomalous adiabatic descent that warms the TP. However, during the cold phase of the AMV, the negative NAO does not persist into March. The Rossby wave train propagates along the well-separated polar and subtropical westerly jets, and the NAO&#8722;TPSAT connection is broken. Further investigation suggests that the enhanced synoptic eddy and low-frequency flow (SELF) interaction over the North Atlantic in February and March during the AMV+, caused by the enhanced and southward-shifted storm track, help maintain the NAO anomaly pattern via positive eddy feedback. This study provides a new detailed perspective on the decadal variability of the North Atlantic&#8722;TP connections in late winter&#8722;early spring.</p>

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On the relationship between the early spring Indian Ocean's sea surface temperature (SST) and the Tibetan Plateau atmospheric heat source in summer

Global and Planetary Change ◽

10.1016/j.gloplacha.2018.02.011 ◽

2018 ◽

Vol 164 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Chenxu Ji ◽

Yuanzhi Zhang ◽

Qiuming Cheng ◽

Yu Li ◽

Tingchen Jiang ◽

...

Keyword(s):

Tibetan Plateau ◽

Heat Source ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Early Spring ◽

Sea Surface ◽

The Tibetan Plateau ◽

Atmospheric Heat Source ◽

Atmospheric Heat ◽

The Relationship

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Spring Dust Mass Flux over the Tibetan Plateau during 2007–19 and Connections with North Atlantic SST Variability

Journal of Climate ◽

10.1175/jcli-d-19-0481.1 ◽

2020 ◽

Vol 33 (22) ◽

pp. 9691-9703

Author(s):

Chao Xu ◽

Yaoming Ma ◽

Jiehua Ma ◽

Chao You ◽

Huijun Wang

Keyword(s):

Tibetan Plateau ◽

North Atlantic ◽

Tarim Basin ◽

Mass Flux ◽

The Tibetan Plateau ◽

Indian Peninsula ◽

The North ◽

Dust Mass ◽

The North Atlantic ◽

Spring Dust

AbstractDust is the major aerosol type over the Tibetan Plateau (TP), and the TP plays an important role in forming the spring dust belt across the Northern Hemisphere in the upper troposphere. Estimated spring dust mass flux (DMF) showed a significant declining trend over the TP during 2007–19. The total spring DMF across the TP (TDMFTP) was mainly affected by DMFs over the Tarim Basin, while the spring DMF across the TP in the midtroposphere was also connected with DMFs over the northwest Indian Peninsula and central Asia. Interannual variability of spring TDMFTP was strongly correlated with the North Atlantic winter sea surface temperature (SST) tripole. A cold preceding winter induced by the North Atlantic winter SST tripole over midlatitude Eurasia promotes dust activities in the subsequent spring. The North Atlantic winter SST tripole anomalies persist into the subsequent spring and induce a corresponding atmosphere response. Enhanced atmospheric baroclinicity develops over northwest China and the northern Indian Peninsula during spring, which is attributed to surface thermal forcing induced by the positive winter SST tripole phase. A strong positive North Atlantic winter SST tripole anomaly strengthens the upper-level westerly jets, enhancing airflow toward the TP midtroposphere; together, these circulation patterns cause anomalous cyclonic conditions in the lower troposphere, especially over the Tarim Basin, via the eastward propagation of a Rossby wave train. These atmospheric circulation conditions are likely to increase the frequency of dust occurrence and promote the transport of dust onto the TP.

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