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Real-Time Realistic Illumination and Rendering of Cumulus Clouds

Sassi Abdessamed, Djedi Noureddine, Sassi Amina
2013 The International Journal of Multimedia & Its Applications  
We propose an efficient and computationally inexpensive phenomenological approach for modelling and rendering cumulus clouds, by drawing on several approaches that we combine and extend.  ...  In addition, traditional computer graphics methods involve high amounts of memory and computing resources, which currently limits their realism and speed.  ...  Voss [4] has used a similar method to produce clouds fractals in their scenes. Kaneda [5] also has simulated the anisotropic scattering in clouds and fog, including a case of multiple scattering.  ... 
doi:10.5121/ijma.2013.5503 fatcat:fp4zkdcf3bdblocicta7cw5hh4

Importance of molecular Rayleigh scattering in the enhancement of clear sky reflectance in the vicinity of boundary layer cumulus clouds

Guoyong Wen, Alexander Marshak, Robert F. Cahalan
2008 Journal of Geophysical Research  
Using cloud optical properties and surface albedo derived from ASTER and MODIS, we performed extensive Monte Carlo simulations of radiative transfer in two cumulus scenes in a biomass burning region in  ...  This study focuses on identifying mechanisms responsible for the enhancement of nadir reflectance in clear regions in the vicinity of cumulus clouds, and quantifies the relative importance of each mechanism  ...  Kaufman in aerosol research.  ... 
doi:10.1029/2008jd010592 fatcat:4omjn5utcfhonjd6xfcowmxyiu

Use of Radiative Transfer Equation (RTE) for Estimating Optical Signal Attenuation through Inhomogeneous Clouds

M. Zaman Malik, S. Sheikh Muhammad
2012 2012 10th International Conference on Frontiers of Information Technology  
in cumulus cloud scene.  ...  It has thus become necessary to accurately model the scattering channel and estimate attenuation suffered by the information bearing optical signal traversing the multiple scattering inhomogeneous clouds  ...  Light propagation through cloud is basically a multiple scattering phenomena.  ... 
doi:10.1109/fit.2012.18 dblp:conf/fit/MalikM12 fatcat:d2dn6gnz6vcvbpui5snkk4u2si

Multiple-scaling methods for Monte Carlo simulations of radiative transfer in cloudy atmosphere

Zhen Wang, Shizhi Yang, Yanli Qiao, Shengcheng Cui, Qiang Zhao
2011 Journal of Quantitative Spectroscopy and Radiative Transfer  
The second method could decrease radiance noise to 0.60% for cumulus and accelerate convergence in optically thin regions.  ...  Two multiple-scaling methods for Monte Carlo simulations were derived from integral radiative transfer equation for calculating radiance in cloudy atmosphere accurately and rapidly.  ...  Acknowledgements The authors thank Victor Venema from Meteorological Institute of Bonn University for the high-resolution cloud fields and are grateful to two anonymous reviewers for their useful comments  ... 
doi:10.1016/j.jqsrt.2011.06.019 fatcat:o357jlvgknhc3frwd2q7hu4a54

Mapping cumulus clouds to scale invariant rough surfaces [article]

J. Cheraghalizadeh, S. Tizdast, H. Mohammadzade, M. N. Najafi
2022 arXiv   pre-print
By simulating the light scattering based on a coarse-grained phenomenological model in a two-dimensional cloud, we argue the possible connection of I to the actual cloud thickness.  ...  Motivated by a recent observation on the self-organized criticality of cumulus clouds (Phys.  ...  As explained in the previous section, the scattering of light inside the cumulus clouds follows the Mie scattering theory.  ... 
arXiv:2204.13783v1 fatcat:ch23hlfxbjaj3hgdd6edlepuqi

Page 393 of Astronomy and Astrophysics Vol. 214, Issue 1-2 [page]

1989 Astronomy and Astrophysics  
Computational procedure We have made multiple scattering calculations for a homogen- eous semi-infinite atmosphere using the phase functions specified in the preceding section.  ...  0.8175 0.707 0.67663 0.403382 Venus 0.761 Saturn 0.620 Maritime haze, 4=0.7 ym Cumulus cloud, 4=0.7 um Clouds of Jupiter, A=0.64 um Clouds of Venus, 4=0.782 ym Clouds of Saturn, 4=0.64 ym ¥ TT TTTT¥T]  ... 

A Numerical Study of Effects of Radiation on Deep Convective Warm Based Cumulus Cloud Development with a 3-D Radiative Transfer Model

Tianyu Zhang, Jiming Sun, Yi Yang
2020 Atmosphere  
The effects of radiation heating and cooling on cumulus cloud development have been the focus of considerable attention for many years.  ...  This study focuses on 3D cloud-radiative interactions in an inhomogeneous cloud field in a large eddy simulation, and the results suggest that compared with the widely used 1D radiative solver in WRF,  ...  In addition, the horizontal transmission and multiple scattering can also cause radiation disturbance in noncloudy regions.  ... 
doi:10.3390/atmos11111187 fatcat:k5wph65p7bdankwy6dklgl7yrq

Significance of multidimensional radiative transfer effects measured in surface fluxes at an Antarctic coastline

Dan Lubin
2002 Journal of Geophysical Research  
under the region's natural variability in cloud cover.  ...  1] At a coastal high-latitude site, multiple reflection of photons between the high albedo surface and an overlying cloud can enhance the downwelling shortwave flux out over the adjacent open water to  ...  UV and visible radiation by conservative scattering clouds which results from differential extinction due to Rayleigh scattering.  ... 
doi:10.1029/2001jd002030 fatcat:nrgo7nl7a5dn5owzic7dlqadku

A survey of modeling, rendering and animation of clouds in computer graphics

Prashant Goswami
2020 The Visual Computer  
Clouds play an important role in enhancing the realism of outdoor scenes in computer graphics (CG).  ...  Realistic cloud generation is a challenging task, which entails processes such as modeling, photorealistic rendering and simulation of the clouds.  ...  The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material.  ... 
doi:10.1007/s00371-020-01953-y fatcat:l5aa44bkzre2bpxqu2xanhvzha

Interactive multiple anisotropic scattering in clouds

Antoine Bouthors, Fabrice Neyret, Nelson Max, Eric Bruneton, Cyril Crassin
2008 Proceedings of the 2008 symposium on Interactive 3D graphics and games - SI3D '08  
We propose an algorithm for the real time realistic simulation of multiple anisotropic scattering of light in a volume.  ...  Our approach consists of estimating the energy transport from the illuminated cloud surface to the rendered cloud pixel for each separate order of multiple scattering.  ...  orders. 6 Estimating light transport in clouds 6.1 Multiple scattering Considering a given cloud pixel to be rendered (corresponding to a location p in the cloud), for each scattering order we look for  ... 
doi:10.1145/1342250.1342277 dblp:conf/si3d/BouthorsNMBC08 fatcat:ou57ohtkyvhcthhqwj6ygsaglq

Dendritic Patterns in Tropical Cumulus: An Observational Analysis

Stephen D. Nicholls, George S. Young
2007 Monthly Weather Review  
Individual cumulus clouds in these dendritic formations are arranged in a compound, hierarchical branching pattern in which each element of the pattern takes the form of a Y-shaped cloud line.  ...  From these sample cases, it was found that dendritic patterns in shallow cumulus occurred over warm tropical oceans in response to cold air advection.  ...  Margaret LeMone and two anonymous reviewers for contributing their varied insights on the mechanisms responsible for inducing mesoscale structure in shallow convection.  ... 
doi:10.1175/mwr3379.1 fatcat:3dsrkfmae5gj7awzsaewf4mcey

High-Performance Rendering of Realistic Cumulus Clouds Using Pre-computed Lighting [article]

Egor Yusov
2014 High Performance Graphics  
We present a new method for rendering realistic cumulus clouds in real time. The clouds in our approach consist of randomly rotated and scaled copies of a single reference particle.  ...  During the pre-processing, we pre-compute optical depth, single and multiple scattering inside the reference particle for every camera position, orientation and light direction, and store the information  ...  Accurately modeling multiple scattering in the cloud is prohibitively expensive, even for off-line renderers.  ... 
doi:10.2312/hpg.20141101 fatcat:w2vxk4jgazbvzciiyu2xn53wye

CLOUD CLASSIFICATION FOR GROUND-BASED SKY IMAGE USING RANDOM FOREST

X. Wan, J. Du
2020 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In this paper, a novel cloud detection method for ground-based sky images is proposed.  ...  Then, Random Forest with this feature set is used to classify different types of cloud and clear sky. The experimental results show that cumulus and cirrus clouds can be identified from sky images.  ...  As a result, the clouds in this region are always classified as cumulus.  ... 
doi:10.5194/isprs-archives-xliii-b3-2020-835-2020 fatcat:wrxmsoqqh5dfpnuzynbnl66xc4

Entrainment-mixing parameterization in shallow cumuli and effects of secondary mixing events

Chun-Song Lu, Yan-Gang Liu, Sheng-Jie Niu
2014 Chinese Science Bulletin  
These results are similar to those in the stratocumulus clouds, but proved valid for the first time in observed cumulus clouds.  ...  Parameterization of entrainment-mixing processes in cumulus clouds is critical to improve cloud parameterization in models, but is still at its infancy.  ...  The scatter of the correlations in observed cumulus clouds is also expected.  ... 
doi:10.1007/s11434-013-0097-1 fatcat:bmouxragabfxhenfhia2sumw5i

MODTRAN Cloud and Multiple Scattering Upgrades with Application to AVIRIS

A. Berk, L.S. Bernstein, G.P. Anderson, P.K. Acharya, D.C. Robertson, J.H. Chetwynd, S.M. Adler-Golden
1998 Remote Sensing of Environment  
comprised of many components, as illustrated in Figure 1 . com AFB, Massachusetts Typically, the quantity to be determined from these mea-  ...  The tions, especially in the presence of clouds and thick aeroaccuracy of MODTRAN, typically 2-5% in transmittance sols, and for multiple scattering in regions of strong (Bernstein et al., 1996a; Anderson  ...  In Proceedings of tion scattering from clouds and aerosols.  ... 
doi:10.1016/s0034-4257(98)00045-5 fatcat:aapixkurhfhenh5lmfrest6g2y
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