scholarly journals Characteristics of Cloud Systems over the Tibetan Plateau and East China during Boreal Summer

2017 ◽  
Vol 30 (9) ◽  
pp. 3117-3137 ◽  
Author(s):  
Jinghua Chen ◽  
Xiaoqing Wu ◽  
Yan Yin ◽  
Qian Huang ◽  
Hui Xiao
Keyword(s):  
Tibetan Plateau ◽  
Diurnal Cycle ◽  
Convective Cloud ◽  
Radiative Heating ◽  
East China ◽  
Boreal Summer ◽  
The Tibetan Plateau ◽  
Cloud Systems ◽  
Convective Clouds ◽  
Cloud Resolving Model

Constrained by ERA-Interim, a cloud-resolving model is employed to characterize cloud systems over the Tibetan Plateau (TP) and east China. The authors focus on analyzing the role of different physical processes on cloud macro- and microscale properties of the cloud systems, especially convective cloud systems between east China and the TP. It is found that convective clouds over the TP are thinner than over east China. This difference is also reflected in the albedo at the top of the atmosphere, where smaller albedos are found for the clouds over the TP. Furthermore, the lifetimes of the deep cloud systems over the TP are shorter than over east China. For the entire simulated period, the latent heat released by phase transitions contributes the most to the total heating and moisture budget, followed by eddy transport over all regions. In addition, radiative heating also plays a nonnegligible role in the total heating effects over the TP. These results also suggest that the influence of ice phase processes is more important over the TP than east China, especially during deep convective periods. Affected by strong surface heat flux, the cloud-top height of convective clouds over the TP exhibits a diurnal cycle, leading to a diurnal cycle of rainfall.

scholarly journals A zonally-oriented teleconnection pattern induced by heating of the western Tibetan Plateau in boreal summer

2021 ◽  
Author(s):  
Qingquan Li ◽  
Mengchu Zhao ◽  
Song Yang ◽  
Xinyong Shen ◽  
Lili Dong ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Heat Source ◽  
General Circulation ◽  
Numerical Models ◽  
Wave Train ◽  
Teleconnection Pattern ◽  
Radiative Heating ◽  
Boreal Summer ◽  
The Tibetan Plateau ◽  
Circumglobal Teleconnection

AbstractThe thermal effect of the Tibetan Plateau (TP) on the northern hemisphere climate has long been a hot topic of scientific research. However, the global effects of the TP heat source are still unclear. We investigate the teleconnection patterns coincident with the TP heat source in boreal summer using both observational data and numerical models including a linearized baroclinic model and an atmospheric general circulation model. The western TP shows the most intense variability in atmospheric heating and the most active connection to atmospheric circulations. The surface sensible heating component of the western TP heat source is associated with a high-latitude wave train propagating from North Japan to central North America through the Bering Sea and Canada. The radiative heating component is accompanied by a wavenumber-4 wave train over Eurasia. We focus on the global zonally-oriented pattern that is connected with the latent heat release from the western TP, referred to here as the TP–circumglobal teleconnection (TP-CGT). The TP-CGT pattern is triggered by the western TP latent heating in two parts starting from the TP: an eastward-propagating wave train trapped in the westerly jet stream and a westward Rossby wave response. The TP-CGT accounts for above 18% of the total variance of the circumglobal teleconnection pattern and modulates mid-latitude precipitation by superimposition. The western TP is the key region in which diabatic heating can initiate the two atmospheric responses concurrently, and the heating over northeastern Asia or the Indian Peninsula is unable to induce the circumglobal pattern directly. The unique geographical location and strong tropospheric heating also make the western TP as a “transit area” of transferring the indirect impact of the Indian summer monsoon (ISM) to the TP-CGT. These results enhance our understanding of the relationship between the circumglobal teleconnection and the ISM and is helpful for improving the prediction of the circumglobal teleconnection variability.

scholarly journals Resolution Dependency of the Diurnal Cycle of Convective Clouds over the Tibetan Plateau in a Mesoscale Model

2008 ◽  
Vol 86A ◽  
pp. 17-31 ◽  
Author(s):  
Tomonori SATO ◽  
Takao YOSHIKANE ◽  
Masaki SATOH ◽  
Hiroaki MIURA ◽  
Hatsuki FUJINAMI
Keyword(s):  
Tibetan Plateau ◽  
Diurnal Cycle ◽  
Mesoscale Model ◽  
The Tibetan Plateau ◽  
Convective Clouds

scholarly journals Confinement of air in the Asian monsoon anticyclone and pathways of convective air to the stratosphere during the summer season

2020 ◽  
Vol 20 (18) ◽  
pp. 11045-11064 ◽  
Author(s):  
Bernard Legras ◽  
Silvia Bucci
Keyword(s):  
Tibetan Plateau ◽  
Asian Monsoon ◽  
Potential Temperature ◽  
Radiative Heating ◽  
Strong Impact ◽  
The Tibetan Plateau ◽  
Transport Pathways ◽  
Convective Clouds ◽  
The Mean ◽  
High Clouds

Abstract. We study the transport pathways from the top of convective clouds to the lower tropical stratosphere during the Asian monsoon, using a dense cover of Lagrangian trajectories driven by observed clouds and the two reanalyses ERA-Interim and ERA5 with diabatic and kinematic vertical motions. We find that the upward propagation of convective impact is very similar for the kinematic and diabatic trajectories using ERA5, while the two cases strongly differ for ERA-Interim. The parcels that stay confined within the Asian monsoon anticyclone and reach 380 K are mostly of continental origin, while maritime sources dominate when the whole global 380 K surface is considered. Over the continent, the separation of descending and ascending motion occurs at a crossover level near 364 K, which is slightly above the clear-sky zero level of radiative heating rate, except over the Tibetan Plateau. The strong impact of the Tibetan Plateau with respect to its share of high clouds is entirely due to its elevated proportion of high clouds above the crossover. The vertical conduit found in previous studies actually ends where the convective clouds detrain. Subsequent parcel motion is characterized by an ascending spiral that spans the whole anticyclone. The mean age of parcels with respect to convection exhibits a minimum at the centre of the Asian monsoon anticyclone, due to the permanent renewal by fresh convective air, and largest values on the periphery as air spirals out. This contrast is reduced by dilution for increasing altitude. Above 360 K, the confinement can be represented by a simple 1-D process of diabatic advection with loss. The mean loss time is about 13 d and uniform over the range 360 to 420 K, which is compared with a total circulation time of 2 to 3 weeks around the anticyclone. The vertical dilution is consequently exponential with an e-folding potential temperature scale of 15 K (about 3 km). The mechanism is compatible with the appearance of a columnar tracer pattern within the anticyclone. It is noticeable that the tropopause does not exhibit any discontinuity in the transport properties when seen in terms of potential temperature.

scholarly journals Microphysical Properties of Convective Clouds in Summer over the Tibetan Plateau from SNPP/VIIRS Satellite Data

2019 ◽  
Vol 33 (3) ◽  
pp. 433-445
Author(s):  
Zhiguo Yue ◽  
Xing Yu ◽  
Guihua Liu ◽  
Jin Dai ◽  
Yannian Zhu ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Satellite Data ◽  
The Tibetan Plateau ◽  
Convective Clouds ◽  
Microphysical Properties
Sign in / Sign up

Export Citation Format

Share Document