Search results for "Cloud computing"
showing 10 items of 327 documents
Sensitivities of Amazonian clouds to aerosols and updraft speed
2017
Abstract. The effects of aerosol particles and updraft speed on warm-phase cloud microphysical properties are studied in the Amazon region as part of the ACRIDICON-CHUVA experiment. Here we expand the sensitivity analysis usually found in the literature by concomitantly considering cloud evolution, putting the sensitivity quantifications into perspective in relation to in-cloud processing, and by considering the effects on droplet size distribution (DSD) shape. Our in situ aircraft measurements over the Amazon Basin cover a wide range of particle concentration and thermodynamic conditions, from the pristine regions over coastal and forested areas to the southern Amazon, which is highly poll…
The ACRIDICON-CHUVA campaign: Studying tropical deep convective clouds and precipitation over Amazonia using the new German research aircraft HALO
2016
Abstract Between 1 September and 4 October 2014, a combined airborne and ground-based measurement campaign was conducted to study tropical deep convective clouds over the Brazilian Amazon rain forest. The new German research aircraft, High Altitude and Long Range Research Aircraft (HALO), a modified Gulfstream G550, and extensive ground-based instrumentation were deployed in and near Manaus (State of Amazonas). The campaign was part of the German–Brazilian Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud Systems–Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud Resolving Modeling and to the GPM (Global Precipitatio…
Definition of "banner clouds" based on time lapse movies
2007
Abstract. Banner clouds appear on the leeward side of a mountain and resemble a banner or a flag. This article provides a comprehensive definition of "banner clouds". It is based primarily on an extensive collection of time lapse movies, but previous attempts at an explanation of this phenomenon are also taken into account. The following ingredients are considered essential: the cloud must be attached to the mountain but not appear on the windward side; the cloud must originate from condensation of water vapour contained in the air (rather than consist of blowing snow); the cloud must be persistent; and the cloud must not be of convective nature. The definition is illustrated and discussed …
A Theoretical Study of the Wet Removal of Atmospheric Pollutants. Part III: The Uptake, Redistribution, and Deposition of (NH4)2SO4Particles by a Con…
1988
Abstract Our model for the scavenging of aerosol particles has been coupled with the two-dimensional form of the convective cloud model of Clark and Collaborators. The combined model was then used to simulate a convective warm cloud for the meteorological situation which existed at 1100 LST 12 July 1985 over Hawaii; assuming an aerosol size distribution of maritime number concentration and of mixed composition with (NH4)2SO4 as the soluble compound. A shallow model cloud developed 26 min after the onset of convection leading to moderate rain which began after 45 min and ended after 60 min. Various parameters which characterize the dynamics and micophysics of the cloud, as well as the scaven…
Comparing parameterized versus measured microphysical properties of tropical convective cloud bases during the ACRIDICON–CHUVA campaign
2017
The objective of this study is to validate parameterizations that were recently developed for satellite retrievals of cloud condensation nuclei supersaturation spectra, NCCN(S), at cloud base alongside more traditional parameterizations connecting NCCN(S) with cloud base updrafts and drop concentrations. This was based on the HALO aircraft measurements during the ACRIDICON–CHUVA campaign over the Amazon region, which took place in September 2014. The properties of convective clouds were measured with a cloud combination probe (CCP), a cloud and aerosol spectrometer (CAS-DPOL), and a CCN counter onboard the HALO aircraft. An intercomparison of the cloud drop size distributions (DSDs) and the…
Analysis of variability in divergence and turn-over induced by three idealized convective systems with a 3D cloud resolving model
2020
Abstract. The sensitivity of upper tropospheric and lower stratospheric convective outflows and related divergence fields is analysed using an ensemble of cloud resolving model (CM1) simulations in LES-mode including various physically manipulated simulations for three different convective systems initialized with an idealized trigger. The main goal of this study is to assess to what extend the divergence field depends on cloud microphysical processes, the mode of convection and on the processes of convective momentum transport and moist static energy redistribution. We find that latent heat release (representing the microphysical uncertainty) plays an essential role by explaining much of m…
Costs of Using Hybrid Cloud Infrastructure: Towards a General Framework
2012
Cloud computing infrastructure is a state-of-the-art computing as a utility paradigm, offering individuals and organizations instantly-available and scalable computing capacity. Organizations may deploy the cloud infrastructure in own data centers, as a private cloud, or use the public on-demand cloud infrastructure charged on a pay-per-use basis. The organizations may also adopt a hybrid solution, i.e. use public cloud capacity to complement the resources in the private cloud, e.g. during the periods of rapid growth in the demand. One of the important factors that affect the organizations’ decisions to adopt a hybrid cloud is the total cost of acquiring and managing the infrastructure. In …
Cold-atom thermoelectrics
2013
Two coupled reservoirs of cold atoms can be used as a model system to study the thermoelectric effect. [Also see Report by Brantut et al. ]
A framework for evaluating Internet-of-Things platforms: Application provider viewpoint
2014
Widespread adoption of Internet of Things (IoT) applications assumes a sustainable ecosystem of firms creating, distributing, and using these applications. Such an ecosystem often forms around a platform that implements commonly used functionality and offers it to the members of the ecosystem for creating applications and services. In IoT, such a platform may be materialized in a form of a cloud platform that supports the management of connected devices, and the development and use of the applications based on them. A number of cloud platforms targeting IoT applications are available in the market; to prosper, they need to assist the providers of the IoT applications in designing and develo…