The development of a sensitive filter radiometer for the Atmospheric Radiation Measurement (ARM) Program has been reported by Platt et al. (1994, 1995). The aim was to develop a reliable and fast instrument that could be used alongside a lidar to obtain near realtime optical properties of clouds, particularly high ice clouds, as they drifted over an ARM Cloud and Radiation Testbed (CART) site a...

Numerical grid imprinting errors have often been observed in global atmospheric models on icosahedral grids. In this paper we analyse the sources of grid imprinting error related to the usual finite volume discretization of the divergence operator. We introduce the concept of alignment of computational cells, and establish that convergence of second order is attained on aligned cells. Moreover,...

In this chapter, we present a GPU-based implementation of a photon transport model that is particularly effective in global illumination of participating media, including atmospheric geometry such as clouds, smoke, and haze, as well as densely placed, translucent surfaces. The model provides the “perfect” GPU application in the sense that the kernel code can be structured to minimize control fl...

This equation comes from more general quasi-geostrophic models of atmospheric and ocean fluid flow ; the scalar θ represents the temperature and u the divergence free velocity field. The mathematical study of the non-dissipative case has first been proposed by Constantin, Majda and Tabak in [5] where it is shown to be an analogue to the 3D Euler equations. The dissipative case has then been stu...

Abstract In this study, sea ice concentration (SIC) budgets were calculated for five ocean-sea reanalyses (CFSR, C-GLORSv7, GLORYS12v1, NEMO-EnKF and ORAS5), in the Southern Ocean compared with observations. Benefiting from assimilation of SIC, reanalysis products display a realistic representation extent as well area. However, when applying SIC budget diagnostics to decompose changes into cont...

Pseudospectral methods are frequently used in the horizontal directions in large-eddy simulation of atmospheric flows. However, the same approach often creates unphysical oscillations for scalar fields if there are horizontal heterogeneities in the sources and/or sinks, as is usual in air pollution problems. A hybrid approach is developed to combine the use of pseudospectral representation of t...

In this chapter, we present a GPU-based implementation of a photon transport model that is particularly effective in global illumination of participating media, including atmospheric geometry such as clouds, smoke, and haze, as well as densely placed, translucent surfaces. The model provides the “perfect” GPU application in the sense that the kernel code can be structured to minimize control fl...

We have discovered that an electrode containing a conical channel with a small angular divergence can transmit into the vacuum almost 100% of an electrospray ion current produced at atmospheric pressure. Our first implementation of such a conical duct, which we term "ConDuct," uses a conductive plastic pipette tip containing an approximately 1.6° divergent channel at its entrance. We observed t...

In recent times, intuitionistic fuzzy sets introduced by Atanassov has been one of the most powerful and flexible approaches for dealing with complex and uncertain situations of real world. In particular, the concept of divergence between intuitionistic fuzzy sets is important since it has applications in various areas such as image segmentation, decision making, medical diagnosis, pattern reco...

Studies on the evolutionary history of ascomycetes in terms of time scale will help to understand historical patterns that shape their biodiversity. Until now most of dating studies of ascomycetes have focused on major events in fungal evolution but not on divergence events within smaller groups of fungi e.g. within Sordariomycetes. We used molecular dating to estimate the time of separation of...