Abstract Several reanalysis data sets are being used for understanding the role of environmental factors controlling tropical cyclones (TCs) evolution. Six sets, namely, European Center Medium‐range Weather Forecast (ECMWF) ERA‐Interim (ERAI) reanalysis, Global System (GFS) analysis, Japan Meteorological Agency's 55‐year projects (JRA55), Modern‐Era Retrospective Analysis Research and Applications, version 2 (MERRA2) NCEP Climate Reanalysis (CFSR), fifth generation ECMWF atmospheric global...

Abstract Northeast India (NEI), the wettest place on Earth, has experienced a rapid decrease in summer monsoon rainfall (about 355 mm) last 36 years (1979–2014), which serious implications ecosystem and livelihood of people this region. However, it is not clear whether observed drying due to anthropogenic activities or linked with global natural variability. A diagnostic model employed estimate amount recycled rainfall, suggests that about 7% total contributed by local moisture recycling...

Abstract Numerical simulations of a thunderstorm event that occurred in the pre‐monsoon season over North‐Eastern region India (NEI) and Bangladesh are performed using Weather Research Forecasting (WRF) Advanced Model (ARW, version 3.8.1). Doppler weather radar indicates severe convective activity lasted for more than 10 hr. These extremely deep clouds with minimum cloud‐top temperature −70 °C at 19 km were triggered by mixing moist air mass transported from Bay Bengal south dry northwest. A...

Kalb-Ramond (KR) gravity is an intriguing model incorporating local Lorentz violation, and black hole (BH) solutions are known to exist. In this study, we investigate some crucial aspects of BHs endowed with a global monopole charge in the self-interacting KR field. Specifically, study quasinormal modes (QNMs) corresponding scalar, electromagnetic, gravitational perturbations; derive rigorous bounds for greybody factors (GBFs); examine sparsity Hawking radiation. The effects parameters...

We analyze warm tachyonic inflation, proposed in the literature, from viewpoint of four-dimensional effective action for tachyon field on a non-BPS D3-brane. find that consistency with observational data density perturbation and validity requires warped compactification. The number background branes which source flux is found to be order 10, contrast 10 14 standard cold inflationary scenario.

Abstract Wormhole solutions in classical general relativity are unstable and hence non traversable. Morris Thorne discovered a traversable wormhole solution that required the energy momentum tensor of matter sources to violate various conditions out purview standard model particle physics. The search for modified theories gravity has been significant interest decades after first published their results as such violations may be avoided theories. This work comprehensively reviews higher...

ABSTRACT A study was carried out to investigate the rain drop size distribution ( DSD ) characteristics during strong bright band SBB ), weak WBB and no NBB regimes of stratiform by using an L‐band wind profiler Joss–Waldvogel disdrometer at Gadanki (13.5 ° N , 79.20 E a tropical station in India. The events with (bright width >0.49 km) are associated larger mean drops D m ground level compared situations. Different shapes raindrop DSDs these three situations suggest different...

ABSTRACT A study is carried out to investigate the spatio‐temporal variation of properties deep convective systems ( DCSs ) and intense IDCSs in association with lightning hail features along their ice microphysical over South Asia. For this purpose 17 years (1998–2014) Tropical Rainfall Measuring Mission TRMM 4 (2007–2010) CloudSat data during premonsoon monsoon seasons are utilized. Significant variability observed region. During both seasons, deepest (top 1%) found land as well ocean...

Recent result of BICEP2, revealing a larger value tensor to scalar ratio (r), has opened up new investigations the in ationary models fit experimental data. The experiment needs reconfirm results, specifically consistency between Planck and BICEP2. On other hand, combined analysis BICEP2 B, including dust polarization uncertainty, brings down upper limit on r. In this note, we reexamine low energy effective theory Chromo Natural ation model its generalization view such observational We find...

Abstract The dynamical downscaling technique is used for the understanding of physical mechanisms associated with atmospheric phenomena. We have developed high‐resolution analysis (6 km) three tropical cyclones (TCs), namely, Phailin (2013), Nilofar (2014), and Chapala (2015) originated over North Indian Ocean using approach. study aimed at identification appropriate methodology generating so that it becomes useful identifying role environmental internal dynamics on intensification processes...

Traversable wormhole solutions in General Relativity require exotic matter sources that violate the null energy condition (NEC), and such behavior maybe avoided modified gravity. In this study, we analyze conditions for static, spherically symmetric traversable Morris-Thorne wormholes a recently proposed viable $f(R)$ gravity model. We numerically considering both constant variable redshift functions, present space-times respecting NEC, supported by phantom energy-like equation of state...

Wormhole solutions in General Relativity (GR) require exotic matter sources that violate the null energy condition (NEC), and it is well-known higher-order modifications of GR some alternative can support wormholes. In this study, we explore possibility formulating traversable wormholes f (R) modified gravity, which perhaps most widely discussed modification GR, with two approaches. First, to investigate effects geometrical constraints on global characteristics, gauge rr–component metric...

In this work, we studied the inflation in context of [Formula: see text] theory gravity. We assumed functional form to be text], where R is Ricci scalar, T trace energy–momentum tensor and model parameter. The cosmological observable parameters like scalar spectral index tensor-to-scalar ratio are estimated for Double-Well potential. found that good agreement with Planck 2018 data. Further, considering vacuum expectation value potential Planckian, observed admissible range parameter which...

Abstract The spatial‐seasonal variation of rainfall contribution by the height spectrum precipitation systems in terms maximum echo top 20 and 40 dBZ (ETH (max) ETH ) is investigated. study carried out during pre‐monsoon (March–May) monsoon (June–September) over continental, coastal oceanic regions South‐Asia. For this purpose, 17 years (1998–2014) TRMM‐PR 4 (2007–2010) CloudSat‐CPR observations are considered. Over continental (coastal/oceanic) regions, relatively deeper (pre‐monsoon)....

It has been shown earlier [Phys. Rev. D 72, 085006 (2005), Phys. 73, 065010 (2006)] that, in the mixed space, there is an unexpected simple relation between any finite temperature graph and its zero counterpart through a multiplicative scalar operator (termed thermal operator) which carries entire dependence. This holds only imaginary time formalism closed path ($\ensuremath{\sigma}=0$) of real (as well as for conjugate $\ensuremath{\sigma}=1$). We study origin this from more fundamental...

The inflationary models developed in presence of a background radiation can be solution to the reheating problem faced by common cold (isentropic) scenario. A D-brane system comprising k Neuvo–Schwarz (NS) 5-branes with transverse circle and BPS D3-branes world volume parallel NS 5-branes, placed at point on diametrically 5-brane has unstable equilibrium D3-brane geometric tachyonic mode associated displacement brane along circle. Cold scenario been studied connection this tachyon [S. Panda,...

In the present work, daily rainfall is simulated over core monsoon region of India by using a feedforward multilayer perceptron (MLP) model. Daily found to be optimally dependent on four concurrent meteorological parameters, namely, geopotential height, specific humidity, zonal, and meridional wind at 1000 mb, 925 850 700 mb pressure levels during 00, 06, 12, 18 Greenwich Mean Time (GMT). The architecture optimized MLP model consists 64 nodes in input layer, 10 hidden 1 node output layer....

In this work, we examined chromo-natural inflation in the context of warm with constant and variable dissipation coefficients. We studied cosmological perturbation theory model obtained scalar tensor power spectra each case. The sources density fluctuations are mainly thermal inflaton field like a general inflationary model. Finally, observables, namely, spectral index tensor-to-scalar ratio calculated. It is found that observables consistent observational Planck 2018 BICEP bounds for...