scholarly journals Behavior of predicted convective clouds and precipitation in the high-resolution Unified Model over the Indian summer monsoon region

2017 ◽  
Vol 4 (5) ◽  
pp. 303-313 ◽  
Author(s):  
A. Jayakumar ◽  
Jisesh Sethunadh ◽  
R. Rakhi ◽  
T. Arulalan ◽  
Saji Mohandas ◽  
...  
2016 ◽  
Author(s):  
A. Jayakumar ◽  
Ashu Mamgain ◽  
A. S. Jisesh ◽  
Saji Mohandas ◽  
R. Rakhi ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Elli R. Ronay ◽  
Sebastian F. M. Breitenbach ◽  
Jessica L. Oster

MAUSAM ◽  
2021 ◽  
Vol 70 (4) ◽  
pp. 691-708
Author(s):  
U. C. MOHANTY ◽  
H. P. NAYAK ◽  
P. SINHA ◽  
K. K. OSURI ◽  
D. NIYOGI

2016 ◽  
Author(s):  
Chandan Sarangi ◽  
Sachchida Nand Tripathi ◽  
Vijay P. Kanawade ◽  
Ilan Koren ◽  
D. Sivanand Pai

Abstract. Monsoonal rainfall is the primary source of surface water in India. Using 12 years of in-situ and satellite observations, we examined association of aerosol loading with cloud fraction, cloud top pressure, cloud top temperature, and daily surface rainfall over Indian summer monsoon region (ISMR). The analyses showed positive correlations between aerosol loading and cloud properties as well as rainfall. A decrease in outgoing longwave radiation and increase in reflected shortwave radiation at the top of the atmosphere with an increase in aerosol loading further supported a seminal role of aerosols on cloud systems. Significant perturbation in liquid- and ice-phase microphysics was also evident over ISMR. For the polluted cases, delay in the onset of collision-coalescence processes and enhancement in the condensation efficiency, allows for more condensate mass to be lifted up to the mixed-colder phases. This results in the higher mass concentration of bigger sized ice-phase hydrometeors and, therefore, implies that the delayed rain processes eventually lead to more surface rainfall. Numerical simulation of a typical rainfall event case over ISMR using spectral bin microphysical scheme coupled with Weather Research Forecasting (WRF-SBM) model was also performed. Simulated microphysics also illustrated the initial suppression of warm rain coupled with increase in updraft velocity under high aerosol loading leads to enhanced super-cooled liquid droplets above freezing level and ice-phase hydrometeors, resulting in increased accumulated surface rainfall. Thus, both observational and numerical analysis suggest that high aerosol loading may induce cloud invigoration and thereby increasing surface rainfall over the ISMR. While the meteorological variability influence the strength of the observed positive associations, our results suggest that the persistent aerosol-associated deepening of cloud systems and intensification of surface rain amounts was applicable to all the meteorological sub-regimes over the ISMR. Hence, we believe that these results provide a step forward in our ability to address aerosol-cloud-rainfall associations based on satellite observations over ISMR.


2015 ◽  
Vol 16 (3) ◽  
pp. 346-354 ◽  
Author(s):  
Kandula Venkata Subrahmanyam ◽  
Karanam Kishore Kumar ◽  
Alur Narendra Babu

2021 ◽  
Author(s):  
Xinxin Tang ◽  
Jianping Li ◽  
Huqiang Zhang ◽  
Sen Zhao

Abstract Compared with Global Atmosphere 6 (GA6) of the UK Met Office Unified Model (UM), the dry bias over the Indian monsoon region in Global Atmosphere 7 (GA7) is significantly reduced. However, the physical processes controlling how this reduced dry bias in India influences rainfall teleconnections in the extratropics remain unclear. Thus, in this study, we use Rossby wave tracing in a horizontally nonuniform background flow to investigate how the improved simulation of monsoon rainfall in GA7 compared with GA6 affects extratropical rainfall teleconnections. We find that wave rays emanating from the upper troposphere in the Indian monsoon region first propagate westward, then divide into the Northern Hemisphere (NH) subtropical westerlies over Asia and the Southern Hemisphere (SH) subtropical westerlies. The wave ray trajectories in GA7 in years of strong Indian summer monsoon rainfall (ISMR) are closer to observations than those in GA6. We also find that the upper tropospheric meridional winds over the South Asian monsoon region and western Tibetan Plateau are much better simulated in GA7 than in GA6 owning to the improvement of ISMR and South Asian High (SAH), which leads to a more realistic simulation of the wave rays in GA7. The better simulated circulation teleconnections in GA7 then modulate the vertical motion and moisture transport, and hence affect extratropical rainfall anomalies in the NH and SH. This paper provides new insights for the assessment of tropical–extratropical teleconnections in models.


Sign in / Sign up

Export Citation Format

Share Document