Cloud access to interoperable IVOA-compliant VOSpace storage
NASA Astrophysics Data System (ADS)
Bertocco, S.; Dowler, P.; Gaudet, S.; Major, B.; Pasian, F.; Taffoni, G.
2018-07-01
Handling, processing and archiving the huge amount of data produced by the new generation of experiments and instruments in Astronomy and Astrophysics are among the more exciting challenges to address in designing the future data management infrastructures and computing services. We investigated the feasibility of a data management and computation infrastructure, available world-wide, with the aim of merging the FAIR data management provided by IVOA standards with the efficiency and reliability of a cloud approach. Our work involved the Canadian Advanced Network for Astronomy Research (CANFAR) infrastructure and the European EGI federated cloud (EFC). We designed and deployed a pilot data management and computation infrastructure that provides IVOA-compliant VOSpace storage resources and wide access to interoperable federated clouds. In this paper, we detail the main user requirements covered, the technical choices and the implemented solutions and we describe the resulting Hybrid cloud Worldwide infrastructure, its benefits and limitations.
University of Wisconsin Cirrus Remote Sensing Pilot Experiment
NASA Technical Reports Server (NTRS)
Ackerman, Steven A.; Eloranta, Ed W.; Grund, Chris J.; Knuteson, Robert O.; Revercomb, Henry E.; Smith, William L.; Wylie, Donald P.
1993-01-01
During the period of 26 October 1989 through 6 December 1989 a unique complement of measurements was made at the University of Wisconsin-Madison to study the radiative properties of cirrus clouds. Simultaneous observations were obtained from a scanning lidar, two interferometers, a high spectral resolution lidar, geostationary and polar orbiting satellites, radiosonde launches, and a whole-sky imager. This paper describes the experiment, the instruments deployed, and, as an example, the data collected during one day of the experiment.
Instrumentation for surveying the lower part of the atmosphere in extremes conditions
NASA Astrophysics Data System (ADS)
Gobinddass, Marie-Line; Molinie, Jack; Richard, Sandrine; Jean-Louis, Sabrina
To observe atmospheric phenomena such as clouds, precipitation and wind in order to understand how they form and evolve meteorologists use few instruments which allows to measure parameters as temperature, pressure and humidity. In the specific case of Kourou region where the French Space Agency is located the environment and safeguard group works on protecting biodiversity in and around the center. By considering a few scientific challenges in atmospheric science one of the main topics of this work consists on the understanding of the fluctuation of the atmosphere due to natural or industrials perturbations. We have considered a few experiences with many instruments in a large space of more than 1200 km per square. To differentiate and try to quantify industrial cloud from natural cloud or from natural atmosphere, the idea of using a drone has been experimented. The ratio of the cost of such experimentation with the relevance of the results which can be obtained will be discussed here. It is necessary to take into account the turbulence in the atmosphere due to industrial acid cloud or hot cloud. Finally, instead of taking the risk of having airbone measurements with a pilot we have thought of the tetherball due to it lower cost and for security reason. The technical experiment and few type of results will be presented here.
NASA Technical Reports Server (NTRS)
1996-01-01
On this tenth day of the STS-75 mission, the flight crew, Cmdr. Andrew Allen, Pilot Scott Horowitz, Payload Cmdr. Franklin Chang-Diaz, Payload Specialist Umberto Guidoni (Italy), and Missions Specialists Jeffrey Hoffman, Maurizio Cheli (ESA), and Claude Nicollier (ESA), are shown performing middeck and Microgravity lab experiments, including the Material pour l'Etude des Phenomenes Interessant la Solidification sur Terre et en Orbite (MEPHISTO) experiment, as well as some material burn tests. Earth views include cloud cover and horizon shots.
A pilot study of distributed knowledge management and clinical decision support in the cloud.
Dixon, Brian E; Simonaitis, Linas; Goldberg, Howard S; Paterno, Marilyn D; Schaeffer, Molly; Hongsermeier, Tonya; Wright, Adam; Middleton, Blackford
2013-09-01
Implement and perform pilot testing of web-based clinical decision support services using a novel framework for creating and managing clinical knowledge in a distributed fashion using the cloud. The pilot sought to (1) develop and test connectivity to an external clinical decision support (CDS) service, (2) assess the exchange of data to and knowledge from the external CDS service, and (3) capture lessons to guide expansion to more practice sites and users. The Clinical Decision Support Consortium created a repository of shared CDS knowledge for managing hypertension, diabetes, and coronary artery disease in a community cloud hosted by Partners HealthCare. A limited data set for primary care patients at a separate health system was securely transmitted to a CDS rules engine hosted in the cloud. Preventive care reminders triggered by the limited data set were returned for display to clinician end users for review and display. During a pilot study, we (1) monitored connectivity and system performance, (2) studied the exchange of data and decision support reminders between the two health systems, and (3) captured lessons. During the six month pilot study, there were 1339 patient encounters in which information was successfully exchanged. Preventive care reminders were displayed during 57% of patient visits, most often reminding physicians to monitor blood pressure for hypertensive patients (29%) and order eye exams for patients with diabetes (28%). Lessons learned were grouped into five themes: performance, governance, semantic interoperability, ongoing adjustments, and usability. Remote, asynchronous cloud-based decision support performed reasonably well, although issues concerning governance, semantic interoperability, and usability remain key challenges for successful adoption and use of cloud-based CDS that will require collaboration between biomedical informatics and computer science disciplines. Decision support in the cloud is feasible and may be a reasonable path toward achieving better support of clinical decision-making across the widest range of health care providers. Published by Elsevier B.V.
NASA Technical Reports Server (NTRS)
Kinne, S.; Wiscombe, Warren; Einaudi, Franco (Technical Monitor)
2001-01-01
Understanding the effect of aerosol on cloud systems is one of the major challenges in atmospheric and climate research. Local studies suggest a multitude of influences on cloud properties. Yet the overall effect on cloud albedo, a critical parameter in climate simulations, remains uncertain. NASA's Triana mission will provide, from its EPIC multi-spectral imager, simultaneous data on aerosol properties and cloud reflectivity. With Triana's unique position in space these data will be available not only globally but also over the entire daytime, well suited to accommodate the often short lifetimes of aerosol and investigations around diurnal cycles. This pilot study explores the ability to detect relationships between aerosol properties and cloud reflectivity with sophisticated statistical methods. Sample results using data from the EOS Terra platform to simulate Triana are presented.
2011-08-01
5 Figure 4 Architetural diagram of running Blender on Amazon EC2 through Nimbis...classification of streaming data. Example input images (top left). All digit prototypes (cluster centers) found, with size proportional to frequency (top...Figure 4 Architetural diagram of running Blender on Amazon EC2 through Nimbis 1 http
NASA Astrophysics Data System (ADS)
Jung, Eunsil; Albrecht, Bruce A.; Feingold, Graham; Jonsson, Haflidi H.; Chuang, Patrick; Donaher, Shaunna L.
2016-07-01
Shallow marine cumulus clouds are by far the most frequently observed cloud type over the Earth's oceans; but they are poorly understood and have not been investigated as extensively as stratocumulus clouds. This study describes and discusses the properties and variations of aerosol, cloud, and precipitation associated with shallow marine cumulus clouds observed in the North Atlantic trades during a field campaign (Barbados Aerosol Cloud Experiment- BACEX, March-April 2010), which took place off Barbados where African dust periodically affects the region. The principal observing platform was the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter (TO) research aircraft, which was equipped with standard meteorological instruments, a zenith pointing cloud radar and probes that measured aerosol, cloud, and precipitation characteristics.The temporal variation and vertical distribution of aerosols observed from the 15 flights, which included the most intense African dust event during all of 2010 in Barbados, showed a wide range of aerosol conditions. During dusty periods, aerosol concentrations increased substantially in the size range between 0.5 and 10 µm (diameter), particles that are large enough to be effective giant cloud condensation nuclei (CCN). The 10-day back trajectories showed three distinct air masses with distinct vertical structures associated with air masses originating in the Atlantic (typical maritime air mass with relatively low aerosol concentrations in the marine boundary layer), Africa (Saharan air layer), and mid-latitudes (continental pollution plumes). Despite the large differences in the total mass loading and the origin of the aerosols, the overall shapes of the aerosol particle size distributions were consistent, with the exception of the transition period.The TO was able to sample many clouds at various phases of growth. Maximum cloud depth observed was less than ˜ 3 km, while most clouds were less than 1 km deep. Clouds tend to precipitate when the cloud is thicker than 500-600 m. Distributions of cloud field characteristics (depth, radar reflectivity, Doppler velocity, precipitation) were well identified in the reflectivity-velocity diagram from the cloud radar observations. Two types of precipitation features were observed for shallow marine cumulus clouds that may impact boundary layer differently: first, a classic cloud-base precipitation where precipitation shafts were observed to emanate from the cloud base; second, cloud-top precipitation where precipitation shafts emanated mainly near the cloud tops, sometimes accompanied by precipitation near the cloud base. The second type of precipitation was more frequently observed during the experiment. Only 42-44 % of the clouds sampled were non-precipitating throughout the entire cloud layer and the rest of the clouds showed precipitation somewhere in the cloud, predominantly closer to the cloud top.
2012-05-01
cloud computing 17 NASA Nebula Platform • Cloud computing pilot program at NASA Ames • Integrates open-source components into seamless, self...Mission support • Education and public outreach (NASA Nebula , 2010) 18 NSF Supported Cloud Research • Support for Cloud Computing in...Mell, P. & Grance, T. (2011). The NIST Definition of Cloud Computing. NIST Special Publication 800-145 • NASA Nebula (2010). Retrieved from
NASA Astrophysics Data System (ADS)
Roberts, Greg; Calmer, Radiance; Sanchez, Kevin; Cayez, Grégoire; Nicoll, Kerianne; Hashimshoni, Eyal; Rosenfeld, Daniel; Ansmann, Albert; Sciare, Jean; Ovadneite, Jurgita; Bronz, Murat; Hattenberger, Gautier; Preissler, Jana; Buehl, Johannes; Ceburnis, Darius; O'Dowd, Colin
2016-04-01
Clouds are omnipresent in earth's atmosphere and constitute an important role in regulating the radiative budget of the planet. However, the response of clouds to climate change remains uncertain, in particular, with respect to aerosol-cloud interactions and feedback mechanisms between the biosphere and atmosphere. Aerosol-cloud interactions and their feedbacks are the main themes of the European project FP7 BACCHUS (Impact of Biogenic versus Anthropogenic Emissions on Clouds and Climate: towards a Holistic Understanding). The National Center for Meteorological Research (CNRM-GAME, Toulouse, France) conducted airborne experiments in Cyprus and Ireland in March and August 2015 respectively to link ground-based and satellite observations. Multiple RPAS (remotely piloted aircraft systems) were instrumented for a specific scientific focus to characterize the vertical distribution of aerosol, cloud microphysical properties, radiative fluxes, 3D wind vectors and meteorological state parameters. Flights below and within clouds were coordinated with satellite overpasses to perform 'top-down' closure of cloud micro-physical properties. Measurements of cloud condensation nuclei spectra at the ground-based site have been used to determine cloud microphyical properties using wind vectors and meteorological parameters measured by the RPAS at cloud base. These derived cloud properties have been validated by in-situ RPAS measurements in the cloud and compared to those derived by the Suomi-NPP satellite. In addition, RPAS profiles in Cyprus observed the layers of dust originating from the Arabian Peninsula and the Sahara Desert. These profiles generally show a well-mixed boundary layer and compare well with ground-based LIDAR observations.
NASA Astrophysics Data System (ADS)
Kröhnert, M.; Anderson, R.; Bumberger, J.; Dietrich, P.; Harpole, W. S.; Maas, H.-G.
2018-05-01
Grassland ecology experiments in remote locations requiring quantitative analysis of the biomass in defined plots are becoming increasingly widespread, but are still limited by manual sampling methodologies. To provide a cost-effective automated solution for biomass determination, several photogrammetric techniques are examined to generate 3D point cloud representations of plots as a basis, to estimate aboveground biomass on grassland plots, which is a key ecosystem variable used in many experiments. Methods investigated include Structure from Motion (SfM) techniques for camera pose estimation with posterior dense matching as well as the usage of a Time of Flight (TOF) 3D camera, a laser light sheet triangulation system and a coded light projection system. In this context, plants of small scales (herbage) and medium scales are observed. In the first pilot study presented here, the best results are obtained by applying dense matching after SfM, ideal for integration into distributed experiment networks.
Chemical Processing of Organics within Clouds: Pilot Study at Whiteface Mountain in Upstate NY
NASA Astrophysics Data System (ADS)
Lance, S.; Carlton, A. G.; Barth, M. C.; Schwab, J. J.; Minder, J. R.; Freedman, J. M.; Zhang, J.; Brandt, R. E.; Casson, P.; Brewer, M.; Orlowski, D.; Christiansen, A.
2017-12-01
Aqueous chemical processing within cloud and fog water has been identified as a key process in the formation of secondary organic aerosol (SOA) mass, which is found abundantly throughout the troposphere. Yet, significant uncertainty remains regarding the organic chemical reactions taking place within clouds and the conditions under which those reactions occur. Routine longterm measurements from the Whiteface Mountain (WFM) Research Observatory in upstate NY provide a unique and broad view of regional air quality relevant to the formation of particulate matter within clouds, largely due to the fact that the summit of WFM is within non-precipitating clouds 30-50% in summertime and the site is undisturbed by local sources. An NSF-funded Cloud Chemistry Workshop in Sept 2016 brought together key researchers at WFM to lay out the most pertinent scientific questions relevant to heterogeneous chemistry occurring within fogs and clouds and to discuss preliminary model intercomparisons. The workshop culminated in a plan to coordinate chemical analyses of cloud water samples focused on chemical constituents thought to be most relevant for SOA formation. Workshop participants also recommended that a pilot study be conducted at WFM to better characterize the meteorological conditions, airflow patterns and clouds intercepting the site, in preparation for future intensive field operations focused on the chemical processing of organics within clouds. This presentation will highlight the experimental design and preliminary observations from the pilot study taking place at WFM in August 2017. Upwind below-cloud measurements of aerosol CCN activation efficiency, size distribution and chemical composition will be compared with similar measurements made at the summit. Under certain conditions, we anticipate that aerosols measured at the summit between cloud events will be representative of cloud droplet residuals recently detrained from the frequent shallow cumulus intercepting the summit. Wind LIDAR and radiosonde observations will be used to link the below-cloud and summit observations. These pre- and post- `cloud processed' aerosols will also be compared with the chemical composition of cloud water samples to evaluate changes to the organic partitioning in the aqueous and aerosol phases.
Lidar Studies of Extinction in Clouds in the ECLIPS Project
NASA Technical Reports Server (NTRS)
Martin, C.; Platt, R.; Young, Stuart A.; Patterson, Graeme P.
1992-01-01
The Experimental Cloud Lidar Pilot Study (ECLIPS) project has now had two active phases in 1989 and 1991. A number of laboratories around the world have taken part in the study. The observations have yielded new data on cloud height and structure, and have yielded some useful new information on the retrieval of cloud optical properties, together with the uncertainties involved. Clouds have a major impact on the climate of the earth. They have the effect of reducing the mean surface temperature from 30 C for a cloudless planet to a value of about 15 C for present cloud conditions. However, it is not at all certain how clouds would react to a change in the planetary temperature in the event of climate change due to a radiative forcing from greenhouse gases. Clouds both reflect out sunlight (negative feedback) and enhance the greenhouse effect (positive feedback), but the ultimate sign of cloud feedback is unknown. Because of these uncertainties, campaigns to study clouds intensely were initiated. The International Satellite Cloud Climatology (ISCPP) and the FIRE Campaigns (cirrus and stratocumulus) are examples. The ECLIPS was set up similarly to the above experiments to obtain information specifically on cloud base, but also cloud top (where possible), optical properties, and cloud structure. ECLIPS was designed to allow as many laboratories as possible globally to take part to get the largest range of clouds. It involves observations with elastic backscatter lidar, supported by infrared fluxes at the ground and radiosonde data, as basic instrumentation. More complex experiments using beam filter radiometers, solar pyranometers, and satellite data and often associated with other campaigns were also encouraged to join ECLIPS. Two periods for observation were chosen, Sep. - Dec. 1989 and Apr. - Jul. 1992 into which investigators were requested to fit 30 days of observations. These would be either continuous, or arranged to coincide with NOAA satellite overpasses to obtain AVHRR data. The distribution of the ECLIPS international effort as in 1991 is shown. The main gaps in the global distribution are in the tropics and the Southern Hemisphere.
Stratocumulus Precipitation and Entrainment Experiment (SPEE) Field Campaign Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Albrecht, Bruce; Ghate, Virendra; CADeddu, Maria
2016-06-01
The scientific focus of this project was to examine precipitation and entrainment processes in marine stratocumulus clouds. The entrainment studies focused on characterizing cloud turbulence at cloud top using Doppler cloud radar observations. The precipitation studies focused on characterizing the precipitation and the macroscopic properties (cloud thickness, and liquid water path) of the clouds. This project will contribute to the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s overall objective of providing the remote-sensing observations needed to improve the representation of key cloud processes in climate models. It will be of direct relevance to the componentsmore » of ARM dealing with entrainment and precipitation processes in stratiform clouds. Further, the radar observing techniques that will be used in this study were developed using ARM Southern Great Plains (SGP) facility observations under Atmospheric System Research (ASR) support. The observing systems operating automatously from a site located just north of the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) aircraft hangar in Marina, California during the period of 1 May to 4 November 2015 included: 1. Microwave radiometer: ARM Microwave Radiometer, 3-Channel (MWR3C) with channels centered at 23.834, 30, and 89 GHz; supported by Dr. Maria Cadeddu. 2. Cloud Radar: CIRPAS 95 GHz Frequency Modulated Continuous Wave (FMCW) Cloud Radar (Centroid Frequency Chirp Rate [CFCR]); operations overseen by Drs. Ghate and Albrecht. 3. Ceilometer: Vaisala CK-14; operations overseen by Drs. Ghate and Albrecht.« less
The Experimental Cloud Lidar Pilot Study (ECLIPS) for cloud-radiation research
NASA Technical Reports Server (NTRS)
Platt, C. M.; Young, S. A.; Carswell, A. I.; Pal, S. R.; Mccormick, M. P.; Winker, D. M.; Delguasta, M.; Stefanutti, L.; Eberhard, W. L.; Hardesty, M.
1994-01-01
The Experimental Cloud Lidar Pilot Study (ECLIPS) was initiated to obtain statistics on cloud-base height, extinction, optical depth, cloud brokenness, and surface fluxes. Two observational phases have taken place, in October-December 1989 and April-July 1991, with intensive 30-day periods being selected within the two time intervals. Data are being archived at NASA Langley Research Center and, once there, are readily available to the international scientific community. This article describes the scale of the study in terms of its international involvement and in the range of data being recorded. Lidar observations of cloud height and backscatter coefficient have been taken from a number of ground-based stations spread around the globe. Solar shortwave and infrared longwave fluxes and infrared beam radiance have been measured at the surface wherever possible. The observations have been tailored to occur around the overpass times of the NOAA weather satellites. This article describes in some detail the various retrieval methods used to obtain results on cloud-base height, extinction coefficient, and infrared emittance, paying particular attention to the uncertainties involved.
14 CFR 91.129 - Operations in Class D airspace.
Code of Federal Regulations, 2014 CFR
2014-01-01
...) Unless required by the applicable distance-from-cloud criteria, each pilot operating a large or turbine... applicable distance-from-cloud criteria requires glide path interception closer in, operate that airplane at... required by the prescribed departure procedure for that airport or the applicable distance from clouds...
14 CFR 91.129 - Operations in Class D airspace.
Code of Federal Regulations, 2013 CFR
2013-01-01
...) Unless required by the applicable distance-from-cloud criteria, each pilot operating a large or turbine... applicable distance-from-cloud criteria requires glide path interception closer in, operate that airplane at... required by the prescribed departure procedure for that airport or the applicable distance from clouds...
14 CFR 91.129 - Operations in Class D airspace.
Code of Federal Regulations, 2012 CFR
2012-01-01
...) Unless required by the applicable distance-from-cloud criteria, each pilot operating a large or turbine... applicable distance-from-cloud criteria requires glide path interception closer in, operate that airplane at... required by the prescribed departure procedure for that airport or the applicable distance from clouds...
14 CFR 91.129 - Operations in Class D airspace.
Code of Federal Regulations, 2011 CFR
2011-01-01
...) Unless required by the applicable distance-from-cloud criteria, each pilot operating a large or turbine... applicable distance-from-cloud criteria requires glide path interception closer in, operate that airplane at... required by the prescribed departure procedure for that airport or the applicable distance from clouds...
The pointing errors of geosynchronous satellites
NASA Technical Reports Server (NTRS)
Sikdar, D. N.; Das, A.
1971-01-01
A study of the correlation between cloud motion and wind field was initiated. Cloud heights and displacements were being obtained from a ceilometer and movie pictures, while winds were measured from pilot balloon observations on a near-simultaneous basis. Cloud motion vectors were obtained from time-lapse cloud pictures, using the WINDCO program, for 27, 28 July, 1969, in the Atlantic. The relationship between observed features of cloud clusters and the ambient wind field derived from cloud trajectories on a wide range of space and time scales is discussed.
Clouds, Aerosols, and Precipitation in the Marine Boundary Layer: An Arm Mobile Facility Deployment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Robert; Wyant, Matthew; Bretherton, Christopher S.
The Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) deployment at Graciosa Island in the Azores generated a 21 month (April 2009-December 2010) comprehensive dataset documenting clouds, aerosols and precipitation using the Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF). The scientific aim of the deployment is to gain improved understanding of the interactions of clouds, aerosols and precipitation in the marine boundary layer. Graciosa Island straddles the boundary between the subtropics and midlatitudes in the Northeast Atlantic Ocean, and consequently experiences a great diversity of meteorological and cloudiness conditions. Low clouds are the dominant cloud type, with stratocumulusmore » and cumulus occurring regularly. Approximately half of all clouds contained precipitation detectable as radar echoes below the cloud base. Radar and satellite observations show that clouds with tops from 1- 11 km contribute more or less equally to surface-measured precipitation at Graciosa. A wide range of aerosol conditions was sampled during the deployment consistent with the diversity of sources as indicated by back trajectory analysis. Preliminary findings suggest important two-way interactions between aerosols and clouds at Graciosa, with aerosols affecting light precipitation and cloud radiative properties while being controlled in part by precipitation scavenging. The data from at Graciosa are being compared with short-range forecasts made a variety of models. A pilot analysis with two climate and two weather forecast models shows that they reproduce the observed time-varying vertical structure of lower-tropospheric cloud fairly well, but the cloud-nucleating aerosol concentrations less well. The Graciosa site has been chosen to be a permanent fixed ARM site that became operational in October 2013.« less
Clouds, aerosol, and precipitation in the Marine Boundary Layer: An ARM mobile facility deployment
Wood, Robert; Luke, Ed; Wyant, Matthew; ...
2014-04-27
The Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) deployment at Graciosa Island in the Azores generated a 21-month (April 2009-December 2010) comprehensive dataset documenting clouds, aerosols, and precipitation using the Atmospheric Radiation Measurement Program (ARM) Mobile Facility (AMF). The scientific aim of the deployment is to gain improved understanding of the interactions of clouds, aerosols, and precipitation in the marine boundary layer. Graciosa Island straddles the boundary between the subtropics and midlatitudes in the Northeast Atlantic Ocean and consequently experiences a great diversity of meteorological and cloudiness conditions. Low clouds are the dominant cloud type, with stratocumulusmore » and cumulus occurring regularly. Approximately half of all clouds contained precipitation detectable as radar echoes below the cloud base. Radar and satellite observations show that clouds with tops from 1-11 km contribute more or less equally to surface-measured precipitation at Graciosa. A wide range of aerosol conditions was sampled during the deployment consistent with the diversity of sources as indicated by back-trajectory analysis. Preliminary findings suggest important two-way interactions between aerosols and clouds at Graciosa, with aerosols affecting light precipitation and cloud radiative properties while being controlled in part by precipitation scavenging.The data from Graciosa are being compared with short-range forecasts made with a variety of models. A pilot analysis with two climate and two weather forecast models shows that they reproduce the observed time-varying vertical structure of lower-tropospheric cloud fairly well but the cloud-nucleating aerosol concentrations less well. The Graciosa site has been chosen to be a permanent fixed ARM site that became operational in October 2013.« less
Clouds, Aerosols, and Precipitation in the Marine Boundary Layer: An Arm Mobile Facility Deployment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Robert; Wyant, Matthew; Bretherton, Christopher S.
The Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) 38 deployment at Graciosa Island in the Azores generated a 21 month (April 2009-December 2010) 39 comprehensive dataset documenting clouds, aerosols and precipitation using the Atmospheric 40 Radiation Measurement (ARM) Mobile Facility (AMF). The scientific aim of the deployment is 41 to gain improved understanding of the interactions of clouds, aerosols and precipitation in the 42 marine boundary layer. 43 Graciosa Island straddles the boundary between the subtropics and midlatitudes in the 44 Northeast Atlantic Ocean, and consequently experiences a great diversity of meteorological and 45 cloudiness conditions. Lowmore » clouds are the dominant cloud type, with stratocumulus and cumulus 46 occurring regularly. Approximately half of all clouds contained precipitation detectable as radar 47 echoes below the cloud base. Radar and satellite observations show that clouds with tops from 1-48 11 km contribute more or less equally to surface-measured precipitation at Graciosa. A wide 49 range of aerosol conditions was sampled during the deployment consistent with the diversity of 50 sources as indicated by back trajectory analysis. Preliminary findings suggest important two-way 51 interactions between aerosols and clouds at Graciosa, with aerosols affecting light precipitation 52 and cloud radiative properties while being controlled in part by precipitation scavenging. 53 The data from at Graciosa are being compared with short-range forecasts made a variety 54 of models. A pilot analysis with two climate and two weather forecast models shows that they 55 reproduce the observed time-varying vertical structure of lower-tropospheric cloud fairly well, 56 but the cloud-nucleating aerosol concentrations less well. The Graciosa site has been chosen to 57 be a long-term ARM site that became operational in October 2013.« less
NASA Technical Reports Server (NTRS)
1995-01-01
On this fifth day of the STS-73 sixteen day mission, the crew Cmdr. Kenneth Bowersox, Pilot Kent Rominger, Payload Specialists Albert Sacco and Fred Leslie, and Mission Specialists Kathryn Thornton, Catherine 'Cady' Coleman, and Michael Lopez-Alegria are shown performing several of the spaceborne experiments onboard the United States Microgravity Lab-2 (USML-2). These experiments are downlinked to Mission Control from the Spacelab using the High-Packed Digital Television (HI-PAC) systems onboard the Shuttle. The experiments shown include the Drop Physics Module (DPM) experiment, the Surface Tension Driven Convection Experiment (STDCE), the Protein Crystal Growth (PCG) experiment, and a Hand-Held Diffusion Test Cell experiment. Lopez-Alegria is interviewed in Spanish by two Spanish radio show hosts. Earth views include cloud cover, the Earth's horizon and atmospheric boundary layers, and several oceans.
NASA Technical Reports Server (NTRS)
Page, William A.
1982-01-01
The following six papers report preliminary results obtained from a field experiment designed to study the role of tropical cumulo-nimbus clouds in the transfer of water vapor from the troposphere to the stratosphere over the region of Panama. The measurements were made utilizing special NOAA enhanced IR satellite images, radiosonde-ozonesondes and a NASA U-2 aircraft carrying. nine experiments. The experiments were provided by a group of NASA, NOAA, industry, and university scientists. Measurements included atmospheric humidity, air and cloud top temperatures, atmospheric tracer constituents, cloud particle characteristics and cloud morphology. The aircraft made a total of eleven flights from August 30 through September 18, 1980, from Howard Air Force Base, Panama; the pilots obtained horizontal and vertical profiles in and near convectively active regions and flew around and over cumulo-nimbus towers and through the extended anvils in the stratosphere. Cumulo-nimbus clouds in the tropics appear to play an important role in upward water vapor transport and may represent the principal source influencing the stratospheric water vapor budget. The clouds provide strong vertical circulation in the troposphere, mixing surface air and its trace materials (water vapor, CFM's sulfur compounds, etc.) quickly up to the tropopause. It is usually assumed that large scale mean motions or eddy scale motions transport the trace materials through the tropopause and into the stratosphere where they are further dispersed and react with other stratospheric constituents. The important step between the troposphere and stratosphere for water vapor appears to depend upon the processes occurring at or near the tropopause at the tops of the cumulo-nimbus towers. Several processes have been sugested: (1) The highest towers penetrate the tropopause and carry water in the form of small ice particles directly into the stratosphere. (2) Water vapor from the tops of the cumulonimbus clouds is transported somehow through the tropopause, the vapor pressure being controlled by the temperature at the tops of the clouds; the dryness of the stratosphere could be explained if most of the transport occurs in connection with very high clouds in regions with very high and cold tropopause. (3) Cumulo-nimbus anvils act as terrestrial-radiation shields allowing the ice particle temperatures near cloud tops to cool radiatively below the supersaturation point; this cooling would cause a vapor deposition on the ice particles which will settle out and thus act as water scavengers. The experiment was designed to collect information on these detailed physical processes near and above the tropopause in order to assess their importance and the role they play in controlling stratospheric water vapor humidity.
Factors Influencing the Adoption of Cloud Storage by Information Technology Decision Makers
ERIC Educational Resources Information Center
Wheelock, Michael D.
2013-01-01
This dissertation uses a survey methodology to determine the factors behind the decision to adopt cloud storage. The dependent variable in the study is the intent to adopt cloud storage. Four independent variables are utilized including need, security, cost-effectiveness and reliability. The survey includes a pilot test, field test and statistical…
Genomic Data Commons and Genomic Cloud Pilots - Google Hangout
Join us for a live, moderated discussion about two NCI efforts to expand access to cancer genomics data: the Genomic Data Commons and Genomic Cloud Pilots. NCI subject matters experts will include Louis M. Staudt, M.D., Ph.D., Director Center for Cancer Genomics, Warren Kibbe, Ph.D., Director, NCI Center for Biomedical Informatics and Information Technology, and moderated by Anthony Kerlavage, Ph.D., Chief, Cancer Informatics Branch, Center for Biomedical Informatics and Information Technology. We welcome your questions before and during the Hangout on Twitter using the hashtag #AskNCI.
"Black cloud" vs. "white cloud" physicians - Myth or reality in apheresis medicine?
Pham, Huy P; Raju, Dheeraj; Jiang, Ning; Williams, Lance A
2017-08-01
Many practitioners believe in the phenomenon of either being labeled a "black cloud" or "white cloud" while on-call. A "white-cloud" physician is one who usually gets fewer cases. A "black-cloud" is one who often has more cases. It is unclear if the designation is only superstitious or if there is some merit. Our aim is to objectively assess this phenomenon in apheresis medicine at our center. A one-year prospective study from 12/2014 to 11/2015 was designed to evaluate the number of times apheresis physicians and nurses were involved with emergent apheresis procedures between the hours from 10 PM and 7 AM. Other parameters collected include the names of the physician, apheresis nurse, type of emergent apheresis procedure, day of the week, and season of the year. During the study period, 32 emergent procedures (or "black-cloud" events) occurred. The median time between two consecutive events was 8 days (range: 1-34 days). We found no statistically significant association between the "black-cloud" events and attending physicians, nurses, day of the week, or season of the year by Chi-square and Fisher's analyses. However, exploratory analysis using association rule demonstrated that "black-cloud" events were more likely to happen on Thursday (2.19 times), with attending physician 2 (1.18 times), and during winter (1.15 times). The results of this pilot study may support the common perception that some physicians or nurses are either "black cloud" or "white cloud". A larger, multi-center study population is needed to validate the results of this pilot study. © 2016 Wiley Periodicals, Inc.
Clouds, Aerosol, and Precipitation in the Marine Boundary Layer: An ARM Mobile Facility Deployment
NASA Technical Reports Server (NTRS)
Wood, Robert; Wyant, Matthew; Bretherton, Christopher S.; Remillard, Jasmine; Kollias, Pavlos; Fletcher, Jennifer; Stemmler, Jayson; de Szoeke, Simone; Yuter, Sandra; Miller, Matthew;
2015-01-01
Capsule: A 21-month deployment to Graciosa Island in the northeastern Atlantic Ocean is providing an unprecedented record of the clouds, aerosols and meteorology in a poorly-sampled remote marine environment The Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) deployment at Graciosa Island in the Azores generated a 21 month (April 2009- December 2010) comprehensive dataset documenting clouds, aerosols and precipitation using the Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF). The scientific aim of the deployment is to gain improved understanding of the interactions of clouds, aerosols and precipitation in the marine boundary layer. Graciosa Island straddles the boundary between the subtropics and midlatitudes in the Northeast Atlantic Ocean, and consequently experiences a great diversity of meteorological and cloudiness conditions. Low clouds are the dominant cloud type, with stratocumulus and cumulus occurring regularly. Approximately half of all clouds contained precipitation detectable as radar echoes below the cloud base. Radar and satellite observations show that clouds with tops from 1- 11 km contribute more or less equally to surface-measured precipitation at Graciosa. A wide range of aerosol conditions was sampled during the deployment consistent with the diversity of sources as indicated by back trajectory analysis. Preliminary findings suggest important two-way interactions between aerosols and clouds at Graciosa, with aerosols affecting light precipitation and cloud radiative properties while being controlled in part by precipitation scavenging. The data from at Graciosa are being compared with short-range forecasts made a variety of models. A pilot analysis with two climate and two weather forecast models shows that they reproduce the observed time-varying vertical structure of lower-tropospheric cloud fairly well, but the cloud-nucleating aerosol concentrations less well. The Graciosa site has been chosen to be a permanent fixed ARM site that became operational in October 2013.
NASA Astrophysics Data System (ADS)
Calmer, Radiance; Roberts, Gregory C.; Preissler, Jana; Sanchez, Kevin J.; Derrien, Solène; O'Dowd, Colin
2018-05-01
The importance of vertical wind velocities (in particular positive vertical wind velocities or updrafts) in atmospheric science has motivated the need to deploy multi-hole probes developed for manned aircraft in small remotely piloted aircraft (RPA). In atmospheric research, lightweight RPAs ( < 2.5 kg) are now able to accurately measure atmospheric wind vectors, even in a cloud, which provides essential observing tools for understanding aerosol-cloud interactions. The European project BACCHUS (impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding) focuses on these specific interactions. In particular, vertical wind velocity at cloud base is a key parameter for studying aerosol-cloud interactions. To measure the three components of wind, a RPA is equipped with a five-hole probe, pressure sensors, and an inertial navigation system (INS). The five-hole probe is calibrated on a multi-axis platform, and the probe-INS system is validated in a wind tunnel. Once mounted on a RPA, power spectral density (PSD) functions and turbulent kinetic energy (TKE) derived from the five-hole probe are compared with sonic anemometers on a meteorological mast. During a BACCHUS field campaign at Mace Head Atmospheric Research Station (Ireland), a fleet of RPAs was deployed to profile the atmosphere and complement ground-based and satellite observations of physical and chemical properties of aerosols, clouds, and meteorological state parameters. The five-hole probe was flown on straight-and-level legs to measure vertical wind velocities within clouds. The vertical velocity measurements from the RPA are validated with vertical velocities derived from a ground-based cloud radar by showing that both measurements yield model-simulated cloud droplet number concentrations within 10 %. The updraft velocity distributions illustrate distinct relationships between vertical cloud fields in different meteorological conditions.
NASA Technical Reports Server (NTRS)
Gerrard, Andrew J.; Kane, Timothy J.; Eckermann, Stephen D.; Thayer, Jeffrey P.
2004-01-01
We conducted gravity wave ray-tracing experiments within an atmospheric region centered near the ARCLITE lidar system at Sondrestrom, Greenland (67N, 310 deg E), in efforts to understand lidar observations of both upper stratospheric gravity wave activity and mesospheric clouds during August 1996 and the summer of 2001. The ray model was used to trace gravity waves through realistic three-dimensional daily-varying background atmospheres in the region, based on forecasts and analyses in the troposphere and stratosphere and climatologies higher up. Reverse ray tracing based on upper stratospheric lidar observations at Sondrestrom was also used to try to objectively identify wave source regions in the troposphere. A source spectrum specified by reverse ray tracing experiments in early August 1996 (when atmospheric flow patterns produced enhanced transmission of waves into the upper stratosphere) yielded model results throughout the remainder of August 1996 that agreed best with the lidar observations. The model also simulated increased vertical group propagation of waves between 40 km and 80 km due to intensifying mean easterlies, which allowed many of the gravity waves observed at 40 km over Sondrestrom to propagate quasi-vertically from 40-80 km and then interact with any mesospheric clouds at 80 km near Sondrestrom, supporting earlier experimentally-inferred correlations between upper stratospheric gravity wave activity and mesospheric cloud backscatter from Sondrestrom lidar observations. A pilot experiment of real-time runs with the model in 2001 using weather forecast data as a low-level background produced less agreement with lidar observations. We believe this is due to limitations in our specified tropospheric source spectrum, the use of climatological winds and temperatures in the upper stratosphere and mesosphere, and missing lidar data from important time periods.
The Namibia Early Flood Warning System, A CEOS Pilot Project
NASA Technical Reports Server (NTRS)
Mandl, Daniel; Frye, Stuart; Cappelaere, Pat; Sohlberg, Robert; Handy, Matthew; Grossman, Robert
2012-01-01
Over the past year few years, an international collaboration has developed a pilot project under the auspices of Committee on Earth Observation Satellite (CEOS) Disasters team. The overall team consists of civilian satellite agencies. For this pilot effort, the development team consists of NASA, Canadian Space Agency, Univ. of Maryland, Univ. of Colorado, Univ. of Oklahoma, Ukraine Space Research Institute and Joint Research Center(JRC) for European Commission. This development team collaborates with regional , national and international agencies to deliver end-to-end disaster coverage. In particular, the team in collaborating on this effort with the Namibia Department of Hydrology to begin in Namibia . However, the ultimate goal is to expand the functionality to provide early warning over the South Africa region. The initial collaboration was initiated by United Nations Office of Outer Space Affairs and CEOS Working Group for Information Systems and Services (WGISS). The initial driver was to demonstrate international interoperability using various space agency sensors and models along with regional in-situ ground sensors. In 2010, the team created a preliminary semi-manual system to demonstrate moving and combining key data streams and delivering the data to the Namibia Department of Hydrology during their flood season which typically is January through April. In this pilot, a variety of moderate resolution and high resolution satellite flood imagery was rapidly delivered and used in conjunction with flood predictive models in Namibia. This was collected in conjunction with ground measurements and was used to examine how to create a customized flood early warning system. During the first year, the team made use of SensorWeb technology to gather various sensor data which was used to monitor flood waves traveling down basins originating in Angola, but eventually flooding villages in Namibia. The team made use of standardized interfaces such as those articulated under the Open Cloud Consortium (OGC) Sensor Web Enablement (SWE) set of web services was good [1][2]. However, it was discovered that in order to make a system like this functional, there were many performance issues. Data sets were large and located in a variety of location behind firewalls and had to be accessed across open networks, so security was an issue. Furthermore, the network access acted as bottleneck to transfer map products to where they are needed. Finally, during disasters, many users and computer processes act in parallel and thus it was very easy to overload the single string of computers stitched together in a virtual system that was initially developed. To address some of these performance issues, the team partnered with the Open Cloud Consortium (OCC) who supplied a Computation Cloud located at the University of Illinois at Chicago and some manpower to administer this Cloud. The Flood SensorWeb [3] system was interfaced to the Cloud to provide a high performance user interface and product development engine. Figure 1 shows the functional diagram of the Flood SensorWeb. Figure 2 shows some of the functionality of the Computation Cloud that was integrated. A significant portion of the original system was ported to the Cloud and during the past year, technical issues were resolved which included web access to the Cloud, security over the open Internet, beginning experiments on how to handle surge capacity by using the virtual machines in the cloud in parallel, using tiling techniques to render large data sets as layers on map, interfaces to allow user to customize the data processing/product chain and other performance enhancing techniques. The conclusion reached from the effort and this presentation is that defining the interoperability standards in a small fraction of the work. For example, once open web service standards were defined, many users could not make use of the standards due to security restrictions. Furthermore, once an interoperable sysm is functional, then a surge of users can render a system unusable, especially in the disaster domain.
STS-69 Flight Day 3 Highlights
NASA Technical Reports Server (NTRS)
1995-01-01
On the third day of the STS-69 mission, the flight crew (Cmdr. Dave Walker, Pilot Ken Cockrell, and Mission Specialists Jim Voss, Mike Gernhardt, and Jim Newman) test the Orbital Maneuvering System and prepare for the retrieval of the SPARTAN satellite with a checkout procedure of the space shuttle's robot arm. Physiological and chemical experiments on fluid dynamics are conducted as part of the Sea Lab project. Urine and blood samples from the crew are collected and studied under microgravity conditions, and a slime mold experiment is conducted to determine the properties of motion, growth, and chemistry in zero gravity conditions. Earth views include cloud cover, a hurricane, and a close-up of its eye.
PILOT: optical performance and end-to-end characterisation
NASA Astrophysics Data System (ADS)
Longval, Y.; Misawa, R.; Ade, P.; André, Y.; de Bernardis, P.; Bousquet, F.; Bouzit, M.; Buttice, V.; Charra, M.; Crane, B.; Dubois, J. P.; Engel, C.; Griffin, M.; Hargrave, P.; Leriche, B.; Maestre, S.; Marty, C.; Marty, W.; Masi, S.; Mot, B.; Narbonne, J.; Pajot, F.; Pisano, G.; Ponthieu, N.; Ristorcelli, I.; Rodriguez, L.; Roudil, G.; Simonella, O.; Salatino, M.; Savini, G.; Tucker, C.; Bernard, J.-P.
2017-11-01
PILOT (Polarized Instrument for the Long-wavelength Observations of the Tenuous ISM), is a balloon-borne astronomy experiment dedicated to study the polarization of dust emission from the diffuse ISM in our Galaxy [1]. The observations of PILOT have two major scientific objectives. Firstly, they will allow us to constrain the large-scale geometry of the magnetic field in our Galaxy and to study in details the alignment properties of dust grains with respect to the magnetic field. In this domain, the measurements of PILOT will complement those of the Planck satellite at longer wavelengths. In particular, they will bring information at a better angular resolution, which is critical in crowded regions such as the Galactic plane. They will allow us to better understand how the magnetic field is shaping the ISM material on large scale in molecular clouds, and the role it plays in the gravitational collapse leading to star formation. Secondly, the PILOT observations will allow us to measure for the first time the polarized dust emission towards the most diffuse regions of the sky, where the measurements are the most easily interpreted in terms of the physics of dust. In this particular domain, PILOT will play a role for future CMB missions similar to that played by the Archeops experiment for Planck. The results of PILOT will allow us to gain knowledge about the magnetic properties of dust grains and about the structure of the magnetic field in the diffuse ISM that is necessary to a precise foreground subtraction in future polarized CMB measurements. The PILOT measurements, combined with those of Planck at longer wavelengths, will therefore allow us to further constrain the dust models. The outcome of such studies will likely impact the instrumental and technical choices for the future space missions dedicated to CMB polarization. The PILOT instrument will allow observations in two photometric channels at wavelengths 240 μm and 550 μm, with an angular resolution of a few arcminutes. We will make use of large format bolometer arrays, developed for the PACS instrument on board the Herschel satellite. With 1024 detectors per photometric channel and photometric band optimized for the measurement of dust emission, PILOT is likely to become the most sensitive experiment for this type of measurements. The PILOT experiment will take advantage of the large gain in sensitivity allowed by the use of large format, filled bolometer arrays at frequencies more favorable to the detection of dust emission. This paper presents the optical design, optical characterization and its performance. We begin with a presentation of the instrument and the optical system and then we summarise the main optical tests performed. In section III, we present preliminary end-to-end test results.
NASA Astrophysics Data System (ADS)
Krinitskiy, Mikhail; Sinitsyn, Alexey; Gulev, Sergey
2014-05-01
Cloud fraction is a critical parameter for the accurate estimation of short-wave and long-wave radiation - one of the most important surface fluxes over sea and land. Massive estimates of the total cloud cover as well as cloud amount for different layers of clouds are available from visual observations, satellite measurements and reanalyses. However, these data are subject of different uncertainties and need continuous validation against highly accurate in-situ measurements. Sky imaging with high resolution fish eye camera provides an excellent opportunity for collecting cloud cover data supplemented with additional characteristics hardly available from routine visual observations (e.g. structure of cloud cover under broken cloud conditions, parameters of distribution of cloud dimensions). We present operational automatic observational package which is based on fish eye camera taking sky images with high resolution (up to 1Hz) in time and a spatial resolution of 968x648px. This spatial resolution has been justified as an optimal by several sensitivity experiments. For the use of the package at research vessel when the horizontal positioning becomes critical, a special extension of the hardware and software to the package has been developed. These modules provide the explicit detection of the optimal moment for shooting. For the post processing of sky images we developed a software realizing the algorithm of the filtering of sunburn effect in case of small and moderate could cover and broken cloud conditions. The same algorithm accurately quantifies the cloud fraction by analyzing color mixture for each point and introducing the so-called "grayness rate index" for every pixel. The accuracy of the algorithm has been tested using the data collected during several campaigns in 2005-2011 in the North Atlantic Ocean. The collection of images included more than 3000 images for different cloud conditions supplied with observations of standard parameters. The system is fully autonomous and has a block for digital data collection at the hard disk. The system has been tested for a wide range of open ocean cloud conditions and we will demonstrate some pilot results of data processing and physical interpretation of fractional cloud cover estimation.
NIH Data Commons Pilot Phase | Informatics Technology for Cancer Research (ITCR)
The NIH, under the BD2K program, will be launching a Data Commons Pilot Phase to test ways to store, access and share Findable, Accessible, Interoperable and Reusable (FAIR) biomedical data and associated tools in the cloud. The NIH Data Commons Pilot Phase is expected to span fiscal years 2017-2020, with an estimated total budget of approximately $55.5 Million, pending available funds.
14 CFR Appendix I to Part 141 - Additional Aircraft Category and/or Class Rating Course
Code of Federal Regulations, 2010 CFR
2010-01-01
.... (b) For a private pilot certificate, the following aeronautical knowledge areas must be included in a... Aviation Administration for private pilot privileges, limitations, and flight operations; (2) Safe and..., including knowledge and effects of fronts, frontal characteristics, cloud formations, icing, and upper-air...
14 CFR Appendix I to Part 141 - Additional Aircraft Category and/or Class Rating Course
Code of Federal Regulations, 2011 CFR
2011-01-01
.... (b) For a private pilot certificate, the following aeronautical knowledge areas must be included in a... Aviation Administration for private pilot privileges, limitations, and flight operations; (2) Safe and..., including knowledge and effects of fronts, frontal characteristics, cloud formations, icing, and upper-air...
NASA Astrophysics Data System (ADS)
Hill, C. N.; Schools, H.; Research Team Members
2012-12-01
This presentation will report on a classroom pilot study in which we teamed with school teachers in four middle school classes to develop and deploy course modules that connect the real-world to virtual forms of laboratory experiments.The broad goal is to help students realize that seemingly complex Earth system processes can be connected to basic properties of the planet and that this can be illustrated through idealized experiment. Specifically the presentation will describe virtual modules based on on-demand cloud computing technologies that allow students to test the notion that pole equator gradients in radiative forcing together with rotation can explain characteristic patterns of flow in the atmosphere. The module developed aligns with new Massachusetts science standard requirements regarding understanding of weather and climate processes. These new standards emphasize an appreciation of differential solar heating and a qualitative understanding of the significance of rotation. In our preliminary classroom pilot studies we employed pre and post evaluation tests to establish that the modules had increased student knowledge of phenomenology and terms. We will describe the results of these tests as well as results from anecdotal measures of student response. This pilot study suggests that one way to help make Earth science concepts more tractable to a wider audience is through virtual experiments that distill phenomena down, but still retain enough detail that students can see the connection to the real world. Modern computer technology and developments in research models appear to provide an opportunity for more work in this area. We will describe some follow-up possibilities that we envisage.
The Cloud Area Padovana: from pilot to production
NASA Astrophysics Data System (ADS)
Andreetto, P.; Costa, F.; Crescente, A.; Dorigo, A.; Fantinel, S.; Fanzago, F.; Sgaravatto, M.; Traldi, S.; Verlato, M.; Zangrando, L.
2017-10-01
The Cloud Area Padovana has been running for almost two years. This is an OpenStack-based scientific cloud, spread across two different sites: the INFN Padova Unit and the INFN Legnaro National Labs. The hardware resources have been scaled horizontally and vertically, by upgrading some hypervisors and by adding new ones: currently it provides about 1100 cores. Some in-house developments were also integrated in the OpenStack dashboard, such as a tool for user and project registrations with direct support for the INFN-AAI Identity Provider as a new option for the user authentication. In collaboration with the EU-funded Indigo DataCloud project, the integration with Docker-based containers has been experimented with and will be available in production soon. This computing facility now satisfies the computational and storage demands of more than 70 users affiliated with about 20 research projects. We present here the architecture of this Cloud infrastructure, the tools and procedures used to operate it. We also focus on the lessons learnt in these two years, describing the problems that were found and the corrective actions that had to be applied. We also discuss about the chosen strategy for upgrades, which combines the need to promptly integrate the OpenStack new developments, the demand to reduce the downtimes of the infrastructure, and the need to limit the effort requested for such updates. We also discuss how this Cloud infrastructure is being used. In particular we focus on two big physics experiments which are intensively exploiting this computing facility: CMS and SPES. CMS deployed on the cloud a complex computational infrastructure, composed of several user interfaces for job submission in the Grid environment/local batch queues or for interactive processes; this is fully integrated with the local Tier-2 facility. To avoid a static allocation of the resources, an elastic cluster, based on cernVM, has been configured: it allows to automatically create and delete virtual machines according to the user needs. SPES, using a client-server system called TraceWin, exploits INFN’s virtual resources performing a very large number of simulations on about a thousand nodes elastically managed.
2010-09-01
first, fol- lowed by detailed analysis, finishing with a recap of the same conclusions. In technical terms, this cognitively primes11 the reader and...lowering ceiling, clouds, fog, rain, rising cloud tops, merging cloud layers) b) icing c) thunderstorms d) turbulence 11 In cognitive priming... stylistic differences in the way pilots tend to handle weather. In fact, each group seems to have problems with the exact worst category of weather with
Global positioning system supported pilot's display
NASA Technical Reports Server (NTRS)
Scott, Marshall M., Jr.; Erdogan, Temel; Schwalb, Andrew P.; Curley, Charles H.
1991-01-01
The hardware, software, and operation of the Microwave Scanning Beam Landing System (MSBLS) Flight Inspection System Pilot's Display is discussed. The Pilot's Display is used in conjunction with flight inspection tests that certify the Microwave Scanning Beam Landing System used at Space Shuttle landing facilities throughout the world. The Pilot's Display was developed for the pilot of test aircraft to set up and fly a given test flight path determined by the flight inspection test engineers. This display also aids the aircraft pilot when hazy or cloud cover conditions exist that limit the pilot's visibility of the Shuttle runway during the flight inspection. The aircraft position is calculated using the Global Positioning System and displayed in the cockpit on a graphical display.
Design of a small laser ceilometer and visibility measuring device for helicopter landing sites
NASA Astrophysics Data System (ADS)
Streicher, Jurgen; Werner, Christian; Dittel, Walter
2004-01-01
Hardware development for remote sensing costs a lot of time and money. A virtual instrument based on software modules was developed to optimise a small visibility and cloud base height sensor. Visibility is the parameter describing the turbidity of the atmosphere. This can be done either by a mean value over a path measured by a transmissometer or for each point of the atmosphere like the backscattered intensity of a range resolved lidar measurement. A standard ceilometer detects the altitude of clouds by using the runtime of the laser pulse and the increasing intensity of the back scattered light when hitting the boundary of a cloud. This corresponds to hard target range finding, but with a more sensitive detection. The output of a standard ceilometer is in case of cloud coverage the altitude of one or more layers. Commercial cloud sensors are specified to track cloud altitude at rather large distances (100 m up to 10 km) and are therefore big and expensive. A virtual instrument was used to calculate the system parameters for a small system for heliports at hospitals and landing platforms under visual flight rules (VFR). Helicopter pilots need information about cloud altitude (base not below 500 feet) and/or the visibility conditions (visual range not lower than 600m) at the destinated landing point. Private pilots need this information too when approaching a non-commercial airport. Both values can be measured automatically with the developed small and compact prototype, at the size of a shoebox for a reasonable price.
Weather Avoidance Guidelines for NASA Global Hawk High-Altitude UAS
NASA Technical Reports Server (NTRS)
Cecil, Daniel J.; Zipser, Edward J.; Velden, Chris; Monette, Sarah; Heymsfield, Gerry; Braun, Scott; Newman, Paul; Black, Pete; Black, Michael; Dunion, Jason
2014-01-01
NASA operates two Global Hawk unmanned aircraft systems for Earth Science research projects. In particular, they are used in the Hurricane and Severe Storm Sentinel (HS3) project during 2012, 2013, and 2014 to take measurements from the environment around tropical cyclones, and from directly above tropical cyclones. There is concern that strict adherence to the weather avoidance rules used in 2012 may sacrifice the ability to observe important science targets. We have proposed modifications to these weather avoidance rules that we believe will improve the ability to observe science targets without compromising aircraft safety. The previous guidelines, used in 2012, specified: Do not approach thunderstorms within 25 nm during flight at FL500 or below. When flying above FL500: Do not approach reported lightning within 25NM in areas where cloud tops are reported at FL500 or higher. Aircraft should maintain at least 10000 ft vertical separation from reported lightning if cloud tops are below FL500. No over-flight of cumulus tops higher than FL500. No flight into forecast or reported icing conditions. No flight into forecast or reported moderate or severe turbulence Based on past experience with high-altitude flights over tropical cyclones, we have recommended changing this guidance to: Do not approach thunderstorms within 25 nm during flight at FL500 or below. Aircraft should maintain at least 5000 ft vertical separation from significant convective cloud tops except: a) When cloud tops above FL500: In the event of reported significant lightning activity or indicators of significant overshooting tops, do not approach within 10-25 nm, depending on pilot discretion and advice from Mission Scientist. b) When cloud tops are below FL500, maintain 10000 ft separation from reported significant lightning or indicators of significant overshooting tops. No flight into forecasted or reported icing conditions. No flight into forecasted or reported moderate or severe turbulence The key changes have to do with overflight of high convective cloud tops and those producing lightning. Experience shows that most tropical oceanic convection (including that in tropical cyclones) is relatively gentle even if the cloud tops are quite high, and can be safely overflown. Exceptions are convective elements producing elevated lightning flash rates (more than just the occasional flash, which would trigger avoidance under the previous rules) and significant overshooting cloud tops.
NASA Technical Reports Server (NTRS)
Chambers, Lin H.; Young, David F.; Barkstrom, Bruce R.; Wielicki, Bruce A.
1997-01-01
The first Clouds and the Earth's Radiant Energy System (CERES) instrument will be launched on the Tropical Rainfall Measuring Mission (TRMM) spacecraft from a Japanese launch site in November 1997. This instrument is a follow-on to the Earth Radiation Budget Experiment (ERBE) begun in the 1980's. The instrument will measure the radiation budget - incoming and outgoing radiant energy - of the Earth. It will establish a baseline and look for climatic trends. The major feature of interest is clouds, which play a very strong role in regulating our climate. CERES will identify clear and cloudy regions and determine cloud physical and microphysical properties using imager data from a companion instrument. Validation efforts for the remote sensing algorithms will be intensive. As one component of the validation, the S'COOL (Students' Cloud Observations On-Line) project will involve school children from around the globe in making ground truth measurements at the time of a CERES overpass. Their observations will be collected at the NASA Langley Distributed Active Archive Center (DAAC) and made available over the Internet for educational purposes as well as for use by the CERES Science Team in validation efforts. Pilot testing of the S'COOL project began in January 1997 with two local schools in Southeastern Virginia and one remote site in Montana. This experience is helping guide the development of the S'COOL project. National testing is planned for April 1997, international testing for July 1997, and global testing for October 1997. In 1998, when the CERES instrument is operational, a global observer network should be in place providing useful information to the scientists and learning opportunities to the students.
Aircraft Weather Mitigation for the Next Generation Air Transportation System
NASA Technical Reports Server (NTRS)
Stough, H. Paul, III
2007-01-01
Atmospheric effects on aviation are described by Mahapatra (1999) as including (1) atmospheric phenomena involving air motion - wind shear and turbulence; (2) hydrometeorological phenomena - rain, snow and hail; (3) aircraft icing; (4) low visibility; and (5) atmospheric electrical phenomena. Aircraft Weather Mitigation includes aircraft systems (e.g. airframe, propulsion, avionics, controls) that can be enacted (by a pilot, automation or hybrid systems) to suppress and/or prepare for the effects of encountered or unavoidable weather or to facilitate a crew operational decision-making process relative to weather. Aircraft weather mitigation can be thought of as a continuum (Figure 1) with the need to avoid all adverse weather at one extreme and the ability to safely operate in all weather conditions at the other extreme. Realistic aircraft capabilities fall somewhere between these two extremes. The capabilities of small general aviation aircraft would be expected to fall closer to the "Avoid All Adverse Weather" point, and the capabilities of large commercial jet transports would fall closer to the "Operate in All Weather Conditions" point. The ability to safely operate in adverse weather conditions is dependent upon the pilot s capabilities (training, total experience and recent experience), the airspace in which the operation is taking place (terrain, navigational aids, traffic separation), the capabilities of the airport (approach guidance, runway and taxiway lighting, availability of air traffic control), as well as the capabilities of the airplane. The level of mitigation may vary depending upon the type of adverse weather. For example, a small general aviation airplane may be equipped to operate "in the clouds" without outside visual references, but not be equipped to prevent airframe ice that could be accreted in those clouds.
Pilot Judgment Training and Evaluation. Volume 3.
1982-06-01
Information Manual. 3-1 8. Flight computer . _ 9. Basic navigation: aeronautical charts (sectional and world 4- aeronautical charts); airspace... clouds , traffic, etc., when you needed to and still maintained the course. 4-13 I___________________ -- -I ~ =~- I- -- INSTRUCTOR LESSON PLAN PART I...maintain basic VFR. PART III Observable Behavior Sought: The student will make proper diversions from clouds to maintain basic VFR. PART IV Reinforcements
A cloud based tool for knowledge exchange on local scale flood risk.
Wilkinson, M E; Mackay, E; Quinn, P F; Stutter, M; Beven, K J; MacLeod, C J A; Macklin, M G; Elkhatib, Y; Percy, B; Vitolo, C; Haygarth, P M
2015-09-15
There is an emerging and urgent need for new approaches for the management of environmental challenges such as flood hazard in the broad context of sustainability. This requires a new way of working which bridges disciplines and organisations, and that breaks down science-culture boundaries. With this, there is growing recognition that the appropriate involvement of local communities in catchment management decisions can result in multiple benefits. However, new tools are required to connect organisations and communities. The growth of cloud based technologies offers a novel way to facilitate this process of exchange of information in environmental science and management; however, stakeholders need to be engaged with as part of the development process from the beginning rather than being presented with a final product at the end. Here we present the development of a pilot Local Environmental Virtual Observatory Flooding Tool. The aim was to develop a cloud based learning platform for stakeholders, bringing together fragmented data, models and visualisation tools that will enable these stakeholders to make scientifically informed environmental management decisions at the local scale. It has been developed by engaging with different stakeholder groups in three catchment case studies in the UK and a panel of national experts in relevant topic areas. However, these case study catchments are typical of many northern latitude catchments. The tool was designed to communicate flood risk in locally impacted communities whilst engaging with landowners/farmers about the risk of runoff from the farmed landscape. It has been developed iteratively to reflect the needs, interests and capabilities of a wide range of stakeholders. The pilot tool combines cloud based services, local catchment datasets, a hydrological model and bespoke visualisation tools to explore real time hydrometric data and the impact of flood risk caused by future land use changes. The novel aspects of the pilot tool are; the co-evolution of tools on a cloud based platform with stakeholders, policy and scientists; encouraging different science disciplines to work together; a wealth of information that is accessible and understandable to a range of stakeholders; and provides a framework for how to approach the development of such a cloud based tool in the future. Above all, stakeholders saw the tool and the potential of cloud technologies as an effective means to taking a whole systems approach to solving environmental issues. This sense of community ownership is essential in order to facilitate future appropriate and acceptable land use management decisions to be co-developed by local catchment communities. The development processes and the resulting pilot tool could be applied to local catchments globally to facilitate bottom up catchment management approaches. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
NASA Astrophysics Data System (ADS)
Casey, K. S.; Hausman, S. A.
2016-02-01
In the last year, the NOAA National Oceanographic Data Center (NODC) and its siblings, the National Climatic Data Center and National Geophysical Data Center, were merged into one organization, the NOAA National Centers for Environmental Information (NCEI). Combining its expertise under one management has helped NCEI accelerate its efforts to embrace and integrate private, public, and hybrid cloud environments into its range of data stewardship services. These services span a range of tiers, from basic, long-term preservation and access, through enhanced access and scientific quality control, to authoritative product development and international-level services. Throughout these tiers of stewardship, partnerships and pilot projects have been launched to identify technological and policy-oriented challenges, to establish solutions to these problems, and to highlight success stories for emulation during operational integration of the cloud into NCEI's data stewardship activities. Some of these pilot activities including data storage, access, and reprocessing in Amazon Web Services, the OneStop data discovery and access framework project, and a set of Cooperative Research and Development Agreements under the Big Data Project with Amazon, Google, IBM, Microsoft, and the Open Cloud Consortium. Progress in these efforts will be highlighted along with a future vision of how NCEI could leverage hybrid cloud deployments and federated systems across NOAA to enable effective data stewardship for its oceanographic, atmospheric, climatic, and geophysical Big Data.
Diagnosing turbulence for research aircraft safety using open source toolkits
NASA Astrophysics Data System (ADS)
Lang, T. J.; Guy, N.
Open source software toolkits have been developed and applied to diagnose in-cloud turbulence in the vicinity of Earth science research aircraft, via analysis of ground-based Doppler radar data. Based on multiple retrospective analyses, these toolkits show promise for detecting significant turbulence well prior to cloud penetrations by research aircraft. A pilot study demonstrated the ability to provide mission scientists turbulence estimates in near real time during an actual field campaign, and thus these toolkits are recommended for usage in future cloud-penetrating aircraft field campaigns.
NASA Technical Reports Server (NTRS)
Haggerty, Julie; McDonough, Frank; Black, Jennifer; Landott, Scott; Wolff, Cory; Mueller, Steven; Minnis, Patrick; Smith, William, Jr.
2008-01-01
Operational products used by the U.S. Federal Aviation Administration to alert pilots of hazardous icing provide nowcast and short-term forecast estimates of the potential for the presence of supercooled liquid water and supercooled large droplets. The Current Icing Product (CIP) system employs basic satellite-derived information, including a cloud mask and cloud top temperature estimates, together with multiple other data sources to produce a gridded, three-dimensional, hourly depiction of icing probability and severity. Advanced satellite-derived cloud products developed at the NASA Langley Research Center (LaRC) provide a more detailed description of cloud properties (primarily at cloud top) compared to the basic satellite-derived information used currently in CIP. Cloud hydrometeor phase, liquid water path, cloud effective temperature, and cloud top height as estimated by the LaRC algorithms are into the CIP fuzzy logic scheme and a confidence value is determined. Examples of CIP products before and after the integration of the LaRC satellite-derived products will be presented at the conference.
NASA Technical Reports Server (NTRS)
1995-01-01
On this fifteenth day of the STS-73 sixteen day mission, the crew Cmdr. Kenneth Bowersox, Pilot Kent Rominger, Payload Specialists Albert Sacco and Fred Leslie, and Mission Specialists Kathryn Thornton, Catherine 'Cady' Coleman, and Michael Lopez-Alegria are shown hosting an in-orbit interview with various newspaper reporters from Johnson Space Center, Kennedy Space Center, and Marshall Space Flight Center via satellite hookup. The astronauts were asked questions regarding the status of the United States Microgravity Lab-2 (USML-2) experiments, their personal goals regarding their involvement in the mission, their future in the space program, and general questions about living in space. Earth views included cloud cover and a tropical storm.
STS-69 flight day 6 highlights
NASA Astrophysics Data System (ADS)
1995-09-01
After being awakened by the Beatles song, 'A Hard Days Night', the flightcrew of the STS-69 mission, Cmdr. Dave Walker, Pilot Ken Cockrell, and Mission Specialists Jim Voss, Jim Newman, and Mike Gernhardt, began their sixth day in orbit by monitoring the free orbiting Wake Shield Facility (WSF). Later Cmdr. Walker conducted an interview with television reporters from Atlanta and Boston, answering questions about the mission and general questions about NASA's space program. The crew filmed a video fo themselves performing daily routines (eating, shaving, exercising), as well as some of the physiological experiments, and shuttle equipment maintenance and checkout. One of the secondary experiments included the Commercial Generic Bioprocessing Apparatus-7 (CGBA-7), which served as an incubator and experiment station for a variety of tests (agricultural, pharmaceutical, biomedical, and environmental). Earth views included some cloud cover, the Gulf of Mexico, Texas, and the Atlantic Ocean.
STS-69 Flight Day 6 Highlights
NASA Technical Reports Server (NTRS)
1995-01-01
After being awakened by the Beatles song, 'A Hard Days Night', the flightcrew of the STS-69 mission, Cmdr. Dave Walker, Pilot Ken Cockrell, and Mission Specialists Jim Voss, Jim Newman, and Mike Gernhardt, began their sixth day in orbit by monitoring the free orbiting Wake Shield Facility (WSF). Later Cmdr. Walker conducted an interview with television reporters from Atlanta and Boston, answering questions about the mission and general questions about NASA's space program. The crew filmed a video for themselves performing daily routines (eating, shaving, exercising), as well as some of the physiological experiments, and shuttle equipment maintenance and checkout. One of the secondary experiments included the Commercial Generic Bioprocessing Apparatus-7 (CGBA-7), which served as an incubator and experiment station for a variety of tests (agricultural, pharmaceutical, biomedical, and environmental). Earth views included some cloud cover, the Gulf of Mexico, Texas, and the Atlantic Ocean.
A novel mobile-cloud system for capturing and analyzing wheelchair maneuvering data: A pilot study.
Fu, Jicheng; Jones, Maria; Liu, Tao; Hao, Wei; Yan, Yuqing; Qian, Gang; Jan, Yih-Kuen
2016-01-01
The purpose of this pilot study was to provide a new approach for capturing and analyzing wheelchair maneuvering data, which are critical for evaluating wheelchair users' activity levels. We proposed a mobile-cloud (MC) system, which incorporated the emerging mobile and cloud computing technologies. The MC system employed smartphone sensors to collect wheelchair maneuvering data and transmit them to the cloud for storage and analysis. A k-nearest neighbor (KNN) machine-learning algorithm was developed to mitigate the impact of sensor noise and recognize wheelchair maneuvering patterns. We conducted 30 trials in an indoor setting, where each trial contained 10 bouts (i.e., periods of continuous wheelchair movement). We also verified our approach in a different building. Different from existing approaches that require sensors to be attached to wheelchairs' wheels, we placed the smartphone into a smartphone holder attached to the wheelchair. Experimental results illustrate that our approach correctly identified all 300 bouts. Compared to existing approaches, our approach was easier to use while achieving similar accuracy in analyzing the accumulated movement time and maximum period of continuous movement (p > 0.8). Overall, the MC system provided a feasible way to ease the data collection process and generated accurate analysis results for evaluating activity levels.
A Novel Mobile-Cloud System for Capturing and Analyzing Wheelchair Maneuvering Data: A Pilot Study
Fu, Jicheng; Jones, Maria; Liu, Tao; Hao, Wei; Yan, Yuqing; Qian, Gang; Jan, Yih-Kuen
2016-01-01
The purpose of this pilot study was to provide a new approach for capturing and analyzing wheelchair maneuvering data, which are critical for evaluating wheelchair users’ activity levels. We proposed a mobile-cloud (MC) system, which incorporated the emerging mobile and cloud computing technologies. The MC system employed smartphone sensors to collect wheelchair maneuvering data and transmit them to the cloud for storage and analysis. A K-Nearest-Neighbor (KNN) machine-learning algorithm was developed to mitigate the impact of sensor noise and recognize wheelchair maneuvering patterns. We conducted 30 trials in an indoor setting, where each trial contained 10 bouts (i.e., periods of continuous wheelchair movement). We also verified our approach in a different building. Different from existing approaches that require sensors to be attached to wheelchairs’ wheels, we placed the smartphone into a smartphone holder attached to the wheelchair. Experimental results illustrate that our approach correctly identified all 300 bouts. Compared to existing approaches, our approach was easier to use while achieving similar accuracy in analyzing the accumulated movement time and maximum period of continuous movement (p > 0.8). Overall, the MC system provided a feasible way to ease the data collection process, and generated accurate analysis results for evaluating activity levels. PMID:26479684
Simulation evaluation of a speed-guidance law for Harrier approach transitions
NASA Technical Reports Server (NTRS)
Merrick, Vernon K.; Moralez, Ernesto; Stortz, Michael W.; Hardy, Gordon H.; Gerdes, Ronald M.
1991-01-01
An exponential-deceleration speed guidance law is formulated which mimics the technique currently used by Harrier pilots to perform decelerating approaches to a hover. This guidance law was tested along with an existing two-step constant deceleration speed guidance law, using a fixed-base piloted simulator programmed to represent a YAV-8B Harrier. Decelerating approaches to a hover at a predetermined station-keeping point were performed along a straight (-3 deg glideslope) path in headwinds up to 40 knots and turbulence up to 6 ft./sec. Visibility was fixed at one-quarter nautical mile and 100 ft. cloud ceiling. Three Harrier pilots participated in the experiment. Handling qualities with the aircraft equipped with the standard YAV-8B rate damped attitude stability augmentation system were adequate (level 2) using either speed guidance law. However, the exponential deceleration speed guidance law was rated superior to the constant-deceleration speed guidance law by a Cooper-Harper handling qualities rating of about one unit independent of the level of wind and turbulence. Replacing the attitude control system of the YAV-8B with a high fidelity model following attitude flight controller increased the approach accuracy and reduced the pilot workload. With one minor exception, the handling qualities for the approach were rated satisfactory (level 1). It is concluded that the exponential deceleration speed guidance law is the most cost effective.
Tracking Clouds on Venus using Venus Express Data
NASA Astrophysics Data System (ADS)
Pertzborn, Rosalyn; Limaye, Sanjay; Markiewicz, Wojciech; Jasmin, Tommy; Udgaonkar, Nishant
2014-05-01
In the US, a growing emphasis has been placed on the development of inclusive and authentic educational experiences which promote active participation by the K-12 learning community as well as the general public in NASA's earth and space science research activities. In the face of growing national and international budgetary constraints which present major challenges across all scientific research organizations around the world, the need for scientific communities to dramatically improve strategies for effective public engagement experiences, demonstrating the relevance of earth and space science research contributions to the citizenry, have become paramount. This presentation will provide an introduction to the online Venus Express Cloud tracking applet, an overview of feedback from educational users based on classroom/pilot implementation efforts, as well as the concept's potential viability for the promotion of expanded public participation in the analysis of data in future planetary exploration and research activities, nationally and internationally. Acknowledgements: We wish to acknowledge the contributions of Mr. Nishant Udgaonkar, a summer intern with the S.N. Bose Scholars Program, sponsored by the Science and Engineering Board, Department of Science and Technology, Government of India, the Indo-U.S. Science and Technology Forum, and the University of Wisconsin-Madison. We also wish to acknowledge the Space Science and Engineering Center as well as NASA for supporting this project.
The analysis of polar clouds from AVHRR satellite data using pattern recognition techniques
NASA Technical Reports Server (NTRS)
Smith, William L.; Ebert, Elizabeth
1990-01-01
The cloud cover in a set of summertime and wintertime AVHRR data from the Arctic and Antarctic regions was analyzed using a pattern recognition algorithm. The data were collected by the NOAA-7 satellite on 6 to 13 Jan. and 1 to 7 Jul. 1984 between 60 deg and 90 deg north and south latitude in 5 spectral channels, at the Global Area Coverage (GAC) resolution of approximately 4 km. This data embodied a Polar Cloud Pilot Data Set which was analyzed by a number of research groups as part of a polar cloud algorithm intercomparison study. This study was intended to determine whether the additional information contained in the AVHRR channels (beyond the standard visible and infrared bands on geostationary satellites) could be effectively utilized in cloud algorithms to resolve some of the cloud detection problems caused by low visible and thermal contrasts in the polar regions. The analysis described makes use of a pattern recognition algorithm which estimates the surface and cloud classification, cloud fraction, and surface and cloudy visible (channel 1) albedo and infrared (channel 4) brightness temperatures on a 2.5 x 2.5 deg latitude-longitude grid. In each grid box several spectral and textural features were computed from the calibrated pixel values in the multispectral imagery, then used to classify the region into one of eighteen surface and/or cloud types using the maximum likelihood decision rule. A slightly different version of the algorithm was used for each season and hemisphere because of differences in categories and because of the lack of visible imagery during winter. The classification of the scene is used to specify the optimal AVHRR channel for separating clear and cloudy pixels using a hybrid histogram-spatial coherence method. This method estimates values for cloud fraction, clear and cloudy albedos and brightness temperatures in each grid box. The choice of a class-dependent AVHRR channel allows for better separation of clear and cloudy pixels than does a global choice of a visible and/or infrared threshold. The classification also prevents erroneous estimates of large fractional cloudiness in areas of cloudfree snow and sea ice. The hybrid histogram-spatial coherence technique and the advantages of first classifying a scene in the polar regions are detailed. The complete Polar Cloud Pilot Data Set was analyzed and the results are presented and discussed.
1984-10-07
41G-39-044 (5-13 Oct 1984) --- "Flatirons", cumulonimbus clouds that have flattened out at a high altitude, the result of rapidly rising moist air. At a given altitude, depending on the temperature, wind, and humidity, the cloud mass can no longer rise and the wind aloft shears the cloud. Central Nigeria, an area in which tropical rain forest gives way to dryer savannah lands, lies beneath a layer a heavy haze and smoke. The crew consisted of astronauts Robert L. Crippen, commander; Jon A. McBride, pilot; mission specialist's Kathryn D. Sullivan, Sally K. Ride, and David D. Leestma; Canadian astronaut Marc Garneau, and Paul D. Scully-Power, payload specialist's.
NASA Technical Reports Server (NTRS)
Curry, J. A.; Hobbs, P. V.; King, M. D.; Randall, D. A.; Minnis, P.; Issac, G. A.; Pinto, J. O.; Uttal, T.; Bucholtz, A.; Cripe, D. G.;
1998-01-01
An overview is given of the First ISCCP Regional Experiment (FIRE) Arctic Clouds Experiment that was conducted in the Arctic during April through July, 1998. The principal goal of the field experiment was to gather the data needed to examine the impact of arctic clouds on the radiation exchange between the surface, atmosphere, and space, and to study how the surface influences the evolution of boundary layer clouds. The observations will be used to evaluate and improve climate model parameterizations of cloud and radiation processes, satellite remote sensing of cloud and surface characteristics, and understanding of cloud-radiation feedbacks in the Arctic. The experiment utilized four research aircraft that flew over surface-based observational sites in the Arctic Ocean and Barrow, Alaska. In this paper we describe the programmatic and science objectives of the project, the experimental design (including research platforms and instrumentation), conditions that were encountered during the field experiment, and some highlights of preliminary observations, modelling, and satellite remote sensing studies.
2012-07-01
discomfort. Extreme turbulence could cause physical injuries to pilot/ passengers who are not wearing seat belts. Clear Air Turbulence (CAT) CAT... passengers who are not wearing seat belts. Generally caused by wind shear in the atmosphere where no clouds are present. Mountain Waves Fast...ways in which our analyses could inform the design of information systems. NextGen, in its mature state, envisions pilots having control over
Sorooshian, Armin; MacDonald, Alexander B; Dadashazar, Hossein; Bates, Kelvin H; Coggon, Matthew M; Craven, Jill S; Crosbie, Ewan; Hersey, Scott P; Hodas, Natasha; Lin, Jack J; Negrón Marty, Arnaldo; Maudlin, Lindsay C; Metcalf, Andrew R; Murphy, Shane M; Padró, Luz T; Prabhakar, Gouri; Rissman, Tracey A; Shingler, Taylor; Varutbangkul, Varuntida; Wang, Zhen; Woods, Roy K; Chuang, Patrick Y; Nenes, Athanasios; Jonsson, Haflidi H; Flagan, Richard C; Seinfeld, John H
2018-02-27
Airborne measurements of meteorological, aerosol, and stratocumulus cloud properties have been harmonized from six field campaigns during July-August months between 2005 and 2016 off the California coast. A consistent set of core instruments was deployed on the Center for Interdisciplinary Remotely-Piloted Aircraft Studies Twin Otter for 113 flight days, amounting to 514 flight hours. A unique aspect of the compiled data set is detailed measurements of aerosol microphysical properties (size distribution, composition, bioaerosol detection, hygroscopicity, optical), cloud water composition, and different sampling inlets to distinguish between clear air aerosol, interstitial in-cloud aerosol, and droplet residual particles in cloud. Measurements and data analysis follow documented methods for quality assurance. The data set is suitable for studies associated with aerosol-cloud-precipitation-meteorology-radiation interactions, especially owing to sharp aerosol perturbations from ship traffic and biomass burning. The data set can be used for model initialization and synergistic application with meteorological models and remote sensing data to improve understanding of the very interactions that comprise the largest uncertainty in the effect of anthropogenic emissions on radiative forcing.
Sorooshian, Armin; MacDonald, Alexander B.; Dadashazar, Hossein; Bates, Kelvin H.; Coggon, Matthew M.; Craven, Jill S.; Crosbie, Ewan; Hersey, Scott P.; Hodas, Natasha; Lin, Jack J.; Negrón Marty, Arnaldo; Maudlin, Lindsay C.; Metcalf, Andrew R.; Murphy, Shane M.; Padró, Luz T.; Prabhakar, Gouri; Rissman, Tracey A.; Shingler, Taylor; Varutbangkul, Varuntida; Wang, Zhen; Woods, Roy K.; Chuang, Patrick Y.; Nenes, Athanasios; Jonsson, Haflidi H.; Flagan, Richard C.; Seinfeld, John H.
2018-01-01
Airborne measurements of meteorological, aerosol, and stratocumulus cloud properties have been harmonized from six field campaigns during July-August months between 2005 and 2016 off the California coast. A consistent set of core instruments was deployed on the Center for Interdisciplinary Remotely-Piloted Aircraft Studies Twin Otter for 113 flight days, amounting to 514 flight hours. A unique aspect of the compiled data set is detailed measurements of aerosol microphysical properties (size distribution, composition, bioaerosol detection, hygroscopicity, optical), cloud water composition, and different sampling inlets to distinguish between clear air aerosol, interstitial in-cloud aerosol, and droplet residual particles in cloud. Measurements and data analysis follow documented methods for quality assurance. The data set is suitable for studies associated with aerosol-cloud-precipitation-meteorology-radiation interactions, especially owing to sharp aerosol perturbations from ship traffic and biomass burning. The data set can be used for model initialization and synergistic application with meteorological models and remote sensing data to improve understanding of the very interactions that comprise the largest uncertainty in the effect of anthropogenic emissions on radiative forcing. PMID:29485627
NASA Astrophysics Data System (ADS)
Sorooshian, Armin; MacDonald, Alexander B.; Dadashazar, Hossein; Bates, Kelvin H.; Coggon, Matthew M.; Craven, Jill S.; Crosbie, Ewan; Hersey, Scott P.; Hodas, Natasha; Lin, Jack J.; Negrón Marty, Arnaldo; Maudlin, Lindsay C.; Metcalf, Andrew R.; Murphy, Shane M.; Padró, Luz T.; Prabhakar, Gouri; Rissman, Tracey A.; Shingler, Taylor; Varutbangkul, Varuntida; Wang, Zhen; Woods, Roy K.; Chuang, Patrick Y.; Nenes, Athanasios; Jonsson, Haflidi H.; Flagan, Richard C.; Seinfeld, John H.
2018-02-01
Airborne measurements of meteorological, aerosol, and stratocumulus cloud properties have been harmonized from six field campaigns during July-August months between 2005 and 2016 off the California coast. A consistent set of core instruments was deployed on the Center for Interdisciplinary Remotely-Piloted Aircraft Studies Twin Otter for 113 flight days, amounting to 514 flight hours. A unique aspect of the compiled data set is detailed measurements of aerosol microphysical properties (size distribution, composition, bioaerosol detection, hygroscopicity, optical), cloud water composition, and different sampling inlets to distinguish between clear air aerosol, interstitial in-cloud aerosol, and droplet residual particles in cloud. Measurements and data analysis follow documented methods for quality assurance. The data set is suitable for studies associated with aerosol-cloud-precipitation-meteorology-radiation interactions, especially owing to sharp aerosol perturbations from ship traffic and biomass burning. The data set can be used for model initialization and synergistic application with meteorological models and remote sensing data to improve understanding of the very interactions that comprise the largest uncertainty in the effect of anthropogenic emissions on radiative forcing.
NASA Astrophysics Data System (ADS)
Karlsson, K.
2010-12-01
The EUMETSAT CMSAF project (www.cmsaf.eu) compiles climatological datasets from various satellite sources with emphasis on the use of EUMETSAT-operated satellites. However, since climate monitoring primarily has a global scope, also datasets merging data from various satellites and satellite operators are prepared. One such dataset is the CMSAF historic GAC (Global Area Coverage) dataset which is based on AVHRR data from the full historic series of NOAA-satellites and the European METOP satellite in mid-morning orbit launched in October 2006. The CMSAF GAC dataset consists of three groups of products: Macroscopical cloud products (cloud amount, cloud type and cloud top), cloud physical products (cloud phase, cloud optical thickness and cloud liquid water path) and surface radiation products (including surface albedo). Results will be presented and discussed for all product groups, including some preliminary inter-comparisons with other datasets (e.g., PATMOS-X, MODIS and CloudSat/CALIPSO datasets). A background will also be given describing the basic methodology behind the derivation of all products. This will include a short historical review of AVHRR cloud processing and resulting AVHRR applications at SMHI. Historic GAC processing is one of five pilot projects selected by the SCOPE-CM (Sustained Co-Ordinated Processing of Environmental Satellite data for Climate Monitoring) project organised by the WMO Space programme. The pilot project is carried out jointly between CMSAF and NOAA with the purpose of finding an optimal GAC processing approach. The initial activity is to inter-compare results of the CMSAF GAC dataset and the NOAA PATMOS-X dataset for the case when both datasets have been derived using the same inter-calibrated AVHRR radiance dataset. The aim is to get further knowledge of e.g. most useful multispectral methods and the impact of ancillary datasets (for example from meteorological reanalysis datasets from NCEP and ECMWF). The CMSAF project is currently defining plans for another five years (2012-2017) of operations and development. New GAC reprocessing efforts are planned and new methodologies will be tested. Central questions here will be how to increase the quantitative use of the products through improving error and uncertainty estimates and how to compile the information in a way to allow meaningful and efficient ways of using the data for e.g. validation of climate model information.
Preparatory studies of zero-g cloud drop coalescence experiment
NASA Technical Reports Server (NTRS)
Telford, J. W.; Keck, T. S.
1979-01-01
Experiments to be performed in a weightless environment in order to study collision and coalescence processes of cloud droplets are described. Rain formation in warm clouds, formation of larger cloud drops, ice and water collision processes, and precipitation in supercooled clouds are among the topics covered.
[Sensory illusions in hang-gliding].
Bousquet, F; Bizeau, A; Resche-Rigon, P; Taillemite, J P; De Rotalier
1997-01-01
Sensory illusions in hang-gliding and para-gliding. Hang-gliding and para-gliding are at the moment booming sports. Sensory illusions are physiological phenomena sharing the wrong perception of the pilote's real position in space. These phenomena are very familiar to aeroplane pilotes, they can also be noticed on certain conditions with hang-gliding pilotes. There are many and various sensory illusions, but only illusions of vestibular origin will be dealt with in this article. Vestibular physiology is reminded with the working principle of a semicircular canal. Physiology and laws of physics explain several sensory illusions, especially when the pilote loses his visual landmarks: flying through a cloud, coriolis effect. Also some specific stages of hang-gliding foster those phenomena: spiraling downwards, self-rotation, following an asymetric closing of the parachute, spin on oneself. Therefore a previous briefing for the pilotes seems necessary.
NASA Astrophysics Data System (ADS)
Ritzman, Jaclyn M.
The objective of the Wyoming Weather Modification Pilot Project is to evaluate the effect of glaciogenic seeding on wintertime precipitation over two co-located barriers in southeast Wyoming. Orographic clouds are to be targeted if they meet strict criteria. An analysis of the impact of seeding requires knowledge of the amount of precipitation that fell from seedable clouds. This amount of precipitation was determined by applying the strict seeding criteria to an eight-year simulation from the Weather Research and Forecasting model at 4-km horizontal resolution. Results from the analysis from the model suggested that the fraction of seedable precipitation was 35.1% (35.5%) over the Sierra Madre and Medicine Bow mountain ranges from 2000-2008. This fraction decreases to 23.2% (23.0%) under a warmer, future climate scenario over the Sierra Madres (Medicine Bows).
NASA Technical Reports Server (NTRS)
Schlesinger, R. E.
1984-01-01
The present investigation is concerned with results from an initial set of comparative experiments in a project which utilize a three-dimensional convective storm model. The modeling results presented are related to four comparative experiments, designated Cases A through D. One of two scientific questions considered involves the dynamical processes, either near the cloud top or well within the cloud interior, which contribute to organize cloud thermal patterns such as those revealed by IR satellite imagery for some storms having strong internal cloud-scale rotation. The second question is concerned with differences, in cloud-top height and temperature field characteristics, between thunderstorms with and without significant internal cloud-scale rotation. The four experiments A-D are compared with regard to both interior and cloud-top configurations in the context of the second question. A particular strong-shear experiment, Case B, is analyzed to address question one.
Evidence for Natural Variability in Marine Stratocumulus Cloud Properties Due to Cloud-Aerosol
NASA Technical Reports Server (NTRS)
Albrecht, Bruce; Sharon, Tarah; Jonsson, Haf; Minnis, Patrick; Minnis, Patrick; Ayers, J. Kirk; Khaiyer, Mandana M.
2004-01-01
In this study, aircraft observations from the Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter are used to characterize the variability in drizzle, cloud, and aerosol properties associated with cloud rifts and the surrounding solid clouds observed off the coast of California. A flight made on 16 July 1999 provided measurements directly across an interface between solid and rift cloud conditions. Aircraft instrumentation allowed for measurements of aerosol, cloud droplet, and drizzle spectra. CCN concentrations were measured in addition to standard thermodynamic variables and the winds. A Forward Scatter Spectrometer Probe (FSSP) measured size distribution of cloud-sized droplets. A Cloud Imaging Probe (CIP) was used to measure distributions of drizzle-sized droplets. Aerosol distributions were obtained from a Cloud Aerosol Scatterprobe (CAS). The CAS probe measured aerosols, cloud droplets and drizzle-sized drops; for this study. The CAS probe was used to measure aerosols in the size range of 0.5 micron - 1 micron. Smaller aerosols were characterized using an Ultrafine Condensation Particle Counter (CPC) sensor. The CPC was used to measure particles with diameters greater than 0.003 micron. By subtracting different count concentrations measured with the CPC, this probe was capable of identifying ultrafine particles those falling in the size range of 3 nanometers - 7 nanometers that are believed to be associated with new particle production.
The impact of parametrized convection on cloud feedback.
Webb, Mark J; Lock, Adrian P; Bretherton, Christopher S; Bony, Sandrine; Cole, Jason N S; Idelkadi, Abderrahmane; Kang, Sarah M; Koshiro, Tsuyoshi; Kawai, Hideaki; Ogura, Tomoo; Roehrig, Romain; Shin, Yechul; Mauritsen, Thorsten; Sherwood, Steven C; Vial, Jessica; Watanabe, Masahiro; Woelfle, Matthew D; Zhao, Ming
2015-11-13
We investigate the sensitivity of cloud feedbacks to the use of convective parametrizations by repeating the CMIP5/CFMIP-2 AMIP/AMIP + 4K uniform sea surface temperature perturbation experiments with 10 climate models which have had their convective parametrizations turned off. Previous studies have suggested that differences between parametrized convection schemes are a leading source of inter-model spread in cloud feedbacks. We find however that 'ConvOff' models with convection switched off have a similar overall range of cloud feedbacks compared with the standard configurations. Furthermore, applying a simple bias correction method to allow for differences in present-day global cloud radiative effects substantially reduces the differences between the cloud feedbacks with and without parametrized convection in the individual models. We conclude that, while parametrized convection influences the strength of the cloud feedbacks substantially in some models, other processes must also contribute substantially to the overall inter-model spread. The positive shortwave cloud feedbacks seen in the models in subtropical regimes associated with shallow clouds are still present in the ConvOff experiments. Inter-model spread in shortwave cloud feedback increases slightly in regimes associated with trade cumulus in the ConvOff experiments but is quite similar in the most stable subtropical regimes associated with stratocumulus clouds. Inter-model spread in longwave cloud feedbacks in strongly precipitating regions of the tropics is substantially reduced in the ConvOff experiments however, indicating a considerable local contribution from differences in the details of convective parametrizations. In both standard and ConvOff experiments, models with less mid-level cloud and less moist static energy near the top of the boundary layer tend to have more positive tropical cloud feedbacks. The role of non-convective processes in contributing to inter-model spread in cloud feedback is discussed. © 2015 The Authors.
The impact of parametrized convection on cloud feedback
Webb, Mark J.; Lock, Adrian P.; Bretherton, Christopher S.; Bony, Sandrine; Cole, Jason N. S.; Idelkadi, Abderrahmane; Kang, Sarah M.; Koshiro, Tsuyoshi; Kawai, Hideaki; Ogura, Tomoo; Roehrig, Romain; Shin, Yechul; Mauritsen, Thorsten; Sherwood, Steven C.; Vial, Jessica; Watanabe, Masahiro; Woelfle, Matthew D.; Zhao, Ming
2015-01-01
We investigate the sensitivity of cloud feedbacks to the use of convective parametrizations by repeating the CMIP5/CFMIP-2 AMIP/AMIP + 4K uniform sea surface temperature perturbation experiments with 10 climate models which have had their convective parametrizations turned off. Previous studies have suggested that differences between parametrized convection schemes are a leading source of inter-model spread in cloud feedbacks. We find however that ‘ConvOff’ models with convection switched off have a similar overall range of cloud feedbacks compared with the standard configurations. Furthermore, applying a simple bias correction method to allow for differences in present-day global cloud radiative effects substantially reduces the differences between the cloud feedbacks with and without parametrized convection in the individual models. We conclude that, while parametrized convection influences the strength of the cloud feedbacks substantially in some models, other processes must also contribute substantially to the overall inter-model spread. The positive shortwave cloud feedbacks seen in the models in subtropical regimes associated with shallow clouds are still present in the ConvOff experiments. Inter-model spread in shortwave cloud feedback increases slightly in regimes associated with trade cumulus in the ConvOff experiments but is quite similar in the most stable subtropical regimes associated with stratocumulus clouds. Inter-model spread in longwave cloud feedbacks in strongly precipitating regions of the tropics is substantially reduced in the ConvOff experiments however, indicating a considerable local contribution from differences in the details of convective parametrizations. In both standard and ConvOff experiments, models with less mid-level cloud and less moist static energy near the top of the boundary layer tend to have more positive tropical cloud feedbacks. The role of non-convective processes in contributing to inter-model spread in cloud feedback is discussed. PMID:26438278
STS-69 Flight Day 9 Video File
NASA Technical Reports Server (NTRS)
1995-01-01
The song, 'He's A Tramp', from the Walt Disney cartoon movie, 'Lady and the Tramp', awakened the astronauts, Cmdr. Dave Walker, Pilot Ken Cockrell, and Mission Specialists Jim Voss, Jim Newman, and Mike Gernhardt, on the ninth day of the STS-69 mission. The Wake Shield Facility (WSF) was again unberthed from the shuttle cargo bay and , using the shuttle's robot arm, held over the side of the shuttle for five hours where it collected data on the electrical field build-up around the spacecraft as part of the Charging Hazards and Wake Studies Experiment (CHAWS). Voss and Gernhardt rehearsed their Extravehicular Activity (EVA) spacewalk, which was planned for the next day. Earth views included cloud cover, a hurricane, and its eye.
STS-69 flight day 9 highlights
NASA Astrophysics Data System (ADS)
1995-09-01
The song, 'He's A Tramp', from the Walt Disney cartoon movie, 'Lady and the Tramp', awakened the astronauts, Cmdr. Dave Walker, Pilot Ken Cockrell, and Mission Specialists Jim Voss, Jim Newman, and Mike Gernhardt, on the ninth day of the STS-69 mission. The Wake Shield Facility (WSF) was again unberthed from the shuttle cargo bay and , using the shuttle's robot arm, held over the side of the shuttle for five hours where it collected data on the electrical field build-up around the spacecraft as part of the Charging Hazards and Wake Studies Experiment (CHAWS). Voss and Gernhardt rehearsed their Extravehicular Activity (EVA) spacewalk, which was planned for the next day. Earth views included cloud cover, a hurricane, and its eye.
An Analysis of Cloud Computing with Amazon Web Services for the Atmospheric Science Data Center
NASA Astrophysics Data System (ADS)
Gleason, J. L.; Little, M. M.
2013-12-01
NASA science and engineering efforts rely heavily on compute and data handling systems. The nature of NASA science data is such that it is not restricted to NASA users, instead it is widely shared across a globally distributed user community including scientists, educators, policy decision makers, and the public. Therefore NASA science computing is a candidate use case for cloud computing where compute resources are outsourced to an external vendor. Amazon Web Services (AWS) is a commercial cloud computing service developed to use excess computing capacity at Amazon, and potentially provides an alternative to costly and potentially underutilized dedicated acquisitions whenever NASA scientists or engineers require additional data processing. AWS desires to provide a simplified avenue for NASA scientists and researchers to share large, complex data sets with external partners and the public. AWS has been extensively used by JPL for a wide range of computing needs and was previously tested on a NASA Agency basis during the Nebula testing program. Its ability to support the Langley Science Directorate needs to be evaluated by integrating it with real world operational needs across NASA and the associated maturity that would come with that. The strengths and weaknesses of this architecture and its ability to support general science and engineering applications has been demonstrated during the previous testing. The Langley Office of the Chief Information Officer in partnership with the Atmospheric Sciences Data Center (ASDC) has established a pilot business interface to utilize AWS cloud computing resources on a organization and project level pay per use model. This poster discusses an effort to evaluate the feasibility of the pilot business interface from a project level perspective by specifically using a processing scenario involving the Clouds and Earth's Radiant Energy System (CERES) project.
Cloud microphysical background for the Israel-4 cloud seeding experiment
NASA Astrophysics Data System (ADS)
Freud, Eyal; Koussevitzky, Hagai; Goren, Tom; Rosenfeld, Daniel
2015-05-01
The modest amount of rainfall in Israel occurs in winter storms that bring convective clouds from the Mediterranean Sea when the cold post frontal air interacts with its relatively warm surface. These clouds were seeded in the Israel-1 and Israel-2 cloud glaciogenic seeding experiments, which have shown statistically significant positive effect of added rainfall of at least 13% in northern Israel, whereas the Israel-3 experiment showed no added rainfall in the south. This was followed by operational seeding in the north since 1975. The lack of physical evidence for the causes of the positive effects in the north caused a lack of confidence in the statistical results and led to the Israel-4 randomized seeding experiment in northern Israel. This experiment started in the winter of 2013/14. The main difference from the previous experiments is the focus on the orographic clouds in the catchment of the Sea of Galilee. The decision to commence the experiment was partially based on evidence supporting the existence of seeding potential, which is reported here. Aircraft and satellite microphysical and dynamic measurements of the clouds document the critical roles of aerosols, especially sea spray, on cloud microstructure and precipitation forming processes. It was found that the convective clouds over sea and coastal areas are naturally seeded hygroscopically by sea spray and develop precipitation efficiently. The diminution of the large sea spray aerosols farther inland along with the increase in aerosol concentrations causes the clouds to develop precipitation more slowly. The short time available for the precipitation forming processes in super-cooled orographic clouds over the Golan Heights farthest inland represents the best glaciogenic seeding potential.
Analysis of the Meteorology Associated with the 1998 NASA Glenn Twin Otter Icing Flights
NASA Technical Reports Server (NTRS)
Bernstein, Ben C.
2000-01-01
This document contains a basic analysis of the meteorology associated with the NASA Glenn Twin Otter icing encounters between December 1997 and March 1998. The purpose of this analysis is to provide a meteorological context for the aircraft data collected during these flights. For each case, the following data elements are presented: (1) A brief overview of the Twin Otter encounter, including locations, liquid water contents, temperatures and microphysical makeup of the clouds and precipitation aloft, (2) Upper-air charts, providing hand-analyzed locations of lows, troughs, ridges, saturated/unsaturated air, temperatures, warm/cold advection, and jet streams, (3) Balloon-borne soundings, providing vertical profiles of temperature, moisture and winds, (4) Infrared and visible satellite data, providing cloud locations and cloud top temperature, (5) 3-hourly surface charts, providing hand-analyzed locations of lows, highs, fronts, precipitation (including type) and cloud cover, (6) Hourly, regional radar mosaics, providing fine resolution of the locations of precipitation (including intensity and type), pilot reports of icing (including intensity and type), surface observations of precipitation type and Twin Otter tracks for a one hour window centered on the time of the radar data, and (7) Hourly plots of icing pilot reports, providing the icing intensity, icing type, icing altitudes and aircraft type. Outages occurred in nearly every dataset at some point. All relevant data that was available is presented here. All times are in UTC and all heights are in feet above mean sea level (MSL).
The ISB Cancer Genomics Cloud: A Flexible Cloud-Based Platform for Cancer Genomics Research.
Reynolds, Sheila M; Miller, Michael; Lee, Phyliss; Leinonen, Kalle; Paquette, Suzanne M; Rodebaugh, Zack; Hahn, Abigail; Gibbs, David L; Slagel, Joseph; Longabaugh, William J; Dhankani, Varsha; Reyes, Madelyn; Pihl, Todd; Backus, Mark; Bookman, Matthew; Deflaux, Nicole; Bingham, Jonathan; Pot, David; Shmulevich, Ilya
2017-11-01
The ISB Cancer Genomics Cloud (ISB-CGC) is one of three pilot projects funded by the National Cancer Institute to explore new approaches to computing on large cancer datasets in a cloud environment. With a focus on Data as a Service, the ISB-CGC offers multiple avenues for accessing and analyzing The Cancer Genome Atlas, TARGET, and other important references such as GENCODE and COSMIC using the Google Cloud Platform. The open approach allows researchers to choose approaches best suited to the task at hand: from analyzing terabytes of data using complex workflows to developing new analysis methods in common languages such as Python, R, and SQL; to using an interactive web application to create synthetic patient cohorts and to explore the wealth of available genomic data. Links to resources and documentation can be found at www.isb-cgc.org Cancer Res; 77(21); e7-10. ©2017 AACR . ©2017 American Association for Cancer Research.
NASA Astrophysics Data System (ADS)
Marlton, Graeme; Harrison, Giles; Nicoll, Keri; Williams, Paul
2017-04-01
This work describes the instrument development, characterisation and data analysis from 51 radiosondes specially equipped with accelerometers to measure atmospheric turbulence. Turbulence is hazardous to aircraft as it cannot be observed in advance. It is estimated that turbulence costs the airline industry millions of US dollars a year through damage to aircraft and injuries to passengers and crew. To avoid turbulence pilots and passengers rely on Clear Air Turbulence forecasts, which have limited skill. One limitation in this area is lack of quantitative unbiased observations. The main source of turbulence observations is from commercial airline pilot reports, which are subjective, biased by the size of aircraft and pilot experience. This work seeks to improve understanding of turbulence through a standardised method of turbulence observations amenable throughout the troposphere. A sensing package has been developed to measure the acceleration of the radiosonde as it swings in response to turbulent agitation of its carrier balloon. The accelerometer radiosonde has been compared against multiple turbulence remote sensing methods to characterise its measurements including calibration with Doppler lidar eddy dissipation rate in the boundary layer. A further relationship has been found by comparison with the spectral width of a Mesospheric, Stratospheric and Tropospheric (MST) radar. From the full dataset of accelerometer sonde ascents a standard deviation of 5 m s-2 is defined as a threshold for significant turbulence. The dataset spans turbulence generated in meteorological phenomena such as jet streams, clouds and in the presence of convection. The analysis revealed that 77% of observed turbulence could be explained by the aforementioned phenomena. In jet streams, turbulence generation was often caused by horizontal processes such as deformation. In convection, turbulence is found to form when CAPE >150 J kg-1. Deeper clouds were found to be more turbulent due to the increased intensity of in-cloud processes. The accelerometer data were used to verify the skill of turbulence diagnostics, in order to assess which diagnostics are best at forecasting turbulence. It was found using a Receiver Operating Characteristics curve analysis that turbulence diagnostics calculated using ECMWF high resolution data that featured wind speed, deformation and relative vorticity advection predicted turbulence best with area under curve values of 0.7,0.66 and 0.62 respectively. This work provides a new, safe and inexpensive method to retrieve in-situ information about the turbulent structure of the atmosphere. It can inform the aviation industry through identifying turbulence generation regions and assess which predictive diagnostics are the most skilful.
The Awareness and Challenges of Cloud Computing Adoption on Tertiary Education in Malaysia
NASA Astrophysics Data System (ADS)
Hazreeni Hamzah, Nor; Mahmud, Maziah; Zukri, Shamsunarnie Mohamed; Yaacob, Wan Fairos Wan; Yacob, Jusoh
2017-09-01
This preliminary study aims to investigate the awareness of the adoption of cloud computing among the academicians in tertiary education in Malaysia. Besides, this study also want to explore the possible challenges faced by the academician while adopting this new technology. The pilot study was done on 40 lecturers in Universiti Teknologi MARA Kampus Kota Bharu (UiTMKB) by using self administered questionnaire. The results found that almost half (40 percent) were not aware on the existing of cloud computing in teaching and learning (T&L) process. The challenges confronting the adoption of cloud computing are data insecurity, data insecurity, unsolicited advertisement, lock-in, reluctance to eliminate staff positions, privacy concerns, reliability challenge, regulatory compliance concerns/user control and institutional culture/resistance to change in technology. This possible challenges can be factorized in two major factors which were security and dependency factor and user control and mentality factor.
NASA Astrophysics Data System (ADS)
Wobrock, Wolfram; Flossmann, Andrea I.; Monier, Marie; Pichon, Jean-Marc; Cortez, Laurent; Fournol, Jean-François; Schwarzenböck, Alfons; Mertes, Stephan; Heintzenberg, Jost; Laj, Paolo; Orsi, Giordano; Ricci, Loretta; Fuzzi, Sandro; Brink, Harry Ten; Jongejan, Piet; Otjes, René
The second field campaign of the Cloud Ice Mountain Experiment (CIME) project took place in February 1998 on the mountain Puy de Dôme in the centre of France. The content of residual aerosol particles, of H 2O 2 and NH 3 in cloud droplets was evaluated by evaporating the drops larger than 5 μm in a Counterflow Virtual Impactor (CVI) and by measuring the residual particle concentration and the released gas content. The same trace species were studied behind a round jet impactor for the complementary interstitial aerosol particles smaller than 5 μm diameter. In a second step of experiments, the ambient supercooled cloud was converted to a mixed phase cloud by seeding the cloud with ice particles by the gas release from pressurised gas bottles. A comparison between the physical and chemical characteristics of liquid drops and ice particles allows a study of the fate of the trace constituents during the presence of ice crystals in the cloud. In the present paper, an overview is given of the CIME 98 experiment and the instrumentation deployed. The meteorological situation during the experiment was analysed with the help of a cloud scale model. The microphysics processes and the behaviour of the scavenged aerosol particles before and during seeding are analysed with the detailed microphysical model ExMix. The simulation results agreed well with the observations and confirmed the assumption that the Bergeron-Findeisen process was dominating during seeding and was influencing the partitioning of aerosol particles between drops and ice crystals. The results of the CIME 98 experiment give an insight on microphysical changes, redistribution of aerosol particles and cloud chemistry during the Bergeron-Findeisen process when acting also in natural clouds.
NASA Astrophysics Data System (ADS)
Wilkinson, Mark; Beven, Keith; Brewer, Paul; El-khatib, Yehia; Gemmell, Alastair; Haygarth, Phil; Mackay, Ellie; Macklin, Mark; Marshall, Keith; Quinn, Paul; Stutter, Marc; Thomas, Nicola; Vitolo, Claudia
2013-04-01
Today's world is dominated by a wide range of informatics tools that are readily available to a wide range of stakeholders. There is growing recognition that the appropriate involvement of local communities in land and water management decisions can result in multiple environmental, economic and social benefits. Therefore, local stakeholder groups are increasingly being asked to participate in decision making alongside policy makers, government agencies and scientists. As such, addressing flooding issues requires new ways of engaging with the catchment and its inhabitants at a local level. To support this, new tools and approaches are required. The growth of cloud based technologies offers new novel ways to facilitate this process of exchange of information in earth sciences. The Environmental Virtual Observatory Pilot project (EVOp) is a new initiative from the UK Natural Environment Research Council (NERC) designed to deliver proof of concept for new tools and approaches to support the challenges as outlined above (http://www.evo-uk.org/). The long term vision of the Environmental Virtual Observatory is to: • Make environmental data more visible and accessible to a wide range of potential users including public good applications; • Provide tools to facilitate the integrated analysis of data, greater access to added knowledge and expert analysis and visualisation of the results; • Develop new, added-value knowledge from public and private sector data assets to help tackle environmental challenges. As part of the EVO pilot, an interactive cloud based tool has been developed with local stakeholders. The Local Landscape Visualisation Tool attempts to communicate flood risk in local impacted communities. The tool has been developed iteratively to reflect the needs, interests and capabilities of a wide range of stakeholders. This tool (assessable via a web portal) combines numerous cloud based tools and services, local catchment datasets, hydrological models and novel visualisation techniques. This pilot tool has been developed by engaging with different stakeholder groups in three catchments in the UK; the Afon Dyfi (Wales), the River Tarland (Scotland) and the River Eden (England). Stakeholders were interested in accessing live data in their catchments and looking at different land use change scenarios on flood peaks. Visualisation tools have been created which offer access to real time data (such as river level, rainfall and webcam images). Other tools allow land owners to use cloud based models (example presented here uses Topmodel, a rainfall-runoff model, on a custom virtual machine image on Amazon web services) and local datasets to explore future land use scenarios, allowing them to understand the associated flood risk. Different ways to communicate model uncertainty are currently being investigated and discussed with stakeholders. In summary the pilot project has had positive feedback and has evolved into two unique parts; a web based map tool and a model interface tool. Users can view live data from different sources, combine different data types together (data mash-up), develop local scenarios for land use and flood risk and exploit the dynamic, elastic cloud modelling capability. This local toolkit will reside within a wider EVO platform that will include national and global datasets, models and state of the art cloud computer systems.
Atmospheric Science Data Center
2013-01-23
FIRE III ACE Data Sets The First International Satellite Cloud ... Regional Experiment (FIRE) - Arctic Cloud Experiment (ACE) was conducted April through July of 1998. It was held in conjunction with ... Heat Budget of the Arctic Ocean (SHEBA) Experiment. The FIRE-ACE focused on all aspects of Arctic cloud systems. The main facility was ...
NASA Astrophysics Data System (ADS)
Wan, Junwei; Chen, Hongyan; Zhao, Jing
2017-08-01
According to the requirements of real-time, reliability and safety for aerospace experiment, the single center cloud computing technology application verification platform is constructed. At the IAAS level, the feasibility of the cloud computing technology be applied to the field of aerospace experiment is tested and verified. Based on the analysis of the test results, a preliminary conclusion is obtained: Cloud computing platform can be applied to the aerospace experiment computing intensive business. For I/O intensive business, it is recommended to use the traditional physical machine.
NASA Technical Reports Server (NTRS)
Shie, C.-L.; Tao, W.-K.; Hou, A.; Lin, X.
2006-01-01
The GCE (Goddard Cumulus Ensemble) model, which has been developed and improved at NASA Goddard Space Flight Center over the past two decades, is considered as one of the finer and state-of-the-art CRMs (Cloud Resolving Models) in the research community. As the chosen CRM for a NASA Interdisciplinary Science (IDS) Project, GCE has recently been successfully upgraded into an MPI (Message Passing Interface) version with which great improvement has been achieved in computational efficiency, scalability, and portability. By basically using the large-scale temperature and moisture advective forcing, as well as the temperature, water vapor and wind fields obtained from TRMM (Tropical Rainfall Measuring Mission) field experiments such as SCSMEX (South China Sea Monsoon Experiment) and KWAJEX (Kwajalein Experiment), our recent 2-D and 3-D GCE simulations were able to capture detailed convective systems typical of the targeted (simulated) regions. The GEOS-3 [Goddard EOS (Earth Observing System) Version-3] reanalysis data have also been proposed and successfully implemented for usage in the proposed/performed GCE long-term simulations (i.e., aiming at producing massive simulated cloud data -- Cloud Library) in compensating the scarcity of real field experimental data in both time and space (location). Preliminary 2-D or 3-D pilot results using GEOS-3 data have generally showed good qualitative agreement (yet some quantitative difference) with the respective numerical results using the SCSMEX observations. The first objective of this paper is to ensure the GEOS-3 data quality by comparing the model results obtained from several pairs of simulations using the real observations and GEOS-3 reanalysis data. The different large-scale advective forcing obtained from these two kinds of resources (i.e., sounding observations and GEOS-3 reanalysis) has been considered as a major critical factor in producing various model results. The second objective of this paper is therefore to investigate and present such an impact of large-scale forcing on various modeled quantities (such as hydrometeors, rainfall, and etc.). A third objective is to validate the overall GCE 3-D model performance by comparing the numerical results with sounding observations, as well as available satellite retrievals.
Feasibility study of a zero-gravity (orbital) atmospheric cloud physics experiments laboratory
NASA Technical Reports Server (NTRS)
Hollinden, A. B.; Eaton, L. R.
1972-01-01
A feasibility and concepts study for a zero-gravity (orbital) atmospheric cloud physics experiment laboratory is discussed. The primary objective was to define a set of cloud physics experiments which will benefit from the near zero-gravity environment of an orbiting spacecraft, identify merits of this environment relative to those of groundbased laboratory facilities, and identify conceptual approaches for the accomplishment of the experiments in an orbiting spacecraft. Solicitation, classification and review of cloud physics experiments for which the advantages of a near zero-gravity environment are evident are described. Identification of experiments for potential early flight opportunities is provided. Several significant accomplishments achieved during the course of this study are presented.
Proceedings of the Second Pilot Climate Data System Workshop
NASA Technical Reports Server (NTRS)
1986-01-01
The proceedings of the workshop held on January 29 and 30, 1986 are discussed. Data management, satellite radiance data, clouds, ultraviolet flux variations in the upper atmosphere, rainfall during El Nino events, and the use of optical disks are among the topics covered.
Astronaut John Young in shadow of Lunar Module behind ultraviolet camera
1972-04-22
AS16-114-18439 (22 April 1972) --- Astronaut Charles M. Duke Jr., lunar module pilot, stands in the shadow of the Lunar Module (LM) behind the ultraviolet (UV) camera which is in operation. This photograph was taken by astronaut John W. Young, commander, during the mission's second extravehicular activity (EVA). The UV camera's gold surface is designed to maintain the correct temperature. The astronauts set the prescribed angles of azimuth and elevation (here 14 degrees for photography of the large Magellanic Cloud) and pointed the camera. Over 180 photographs and spectra in far-ultraviolet light were obtained showing clouds of hydrogen and other gases and several thousand stars. The United States flag and Lunar Roving Vehicle (LRV) are in the left background. While astronauts Young and Duke descended in the Apollo 16 Lunar Module (LM) "Orion" to explore the Descartes highlands landing site on the moon, astronaut Thomas K. Mattingly II, command module pilot, remained with the Command and Service Modules (CSM) "Casper" in lunar orbit.
Astronaut Charles M. Duke, Jr., in shadow of Lunar Module behind ultraviolet camera
NASA Technical Reports Server (NTRS)
1972-01-01
Astronaut Charles M. Duke, Jr., lunar module pilot, stands in the shadow of the Lunar Module (LM) behind the ultraviolet (UV) camera which is in operation. This photograph was taken by astronaut John W. Young, mission commander, during the mission's second extravehicular activity (EVA-2). The UV camera's gold surface is designed to maintain the correct temperature. The astronauts set the prescribed angles of azimuth and elevation (here 14 degrees for photography of the large Magellanic Cloud) and pointed the camera. Over 180 photographs and spectra in far-ultraviolet light were obtained showing clouds of hydrogen and other gases and several thousand stars. The United States flag and Lunar Roving Vehicle (LRV) are in the left background. While astronauts Young and Duke descended in the Apollo 16 Lunar Module (lm) 'Orion' to explore the Descartes highlands landing site on the Moon, astronaut Thomas K. Mattingly II, command module pilot, remained with the Command and Service Modules (csm) 'Casper' in lunar orbit.
STS-111 Flight Day 2 Highlights
NASA Technical Reports Server (NTRS)
2002-01-01
On Flight Day 2 of STS-111, the crew of Endeavour (Kenneth Cockrell, Commander; Paul Lockhart, Pilot; Franklin Chang-Diaz, Mission Specialist; Philippe Perrin, Mission Specialist) and the Expedition 5 crew (Valery Korzun, Commander; Peggy Whitson, Flight Engineer; Sergei Treschev, Flight Engineer), having successfully entered orbit around the Earth, begin to maneuver towards the International Space Station (ISS), where the Expedition 5 crew will replace the Expedition 4 crew. Live video is shown of the Earth from several vantage points aboard the Shuttle. The center-line camera, which will allow Shuttle pilots to align the docking apparatus with that on the ISS, provides footage of the Earth. Chang-Diaz participates in an interview, in Spanish, conducted from the ground via radio communications, with Cockrell also appearing. Footage of the Earth includes: Daytime video of the Eastern United States with some cloud cover as Endeavour passes over the Florida panhandle, Georgia, and the Carolinas; Daytime video of Lake Michigan unobscured by cloud cover; Nighttime low-light camera video of Madrid, Spain.
Atmospheric microphysical experiments on an orbital platform
NASA Technical Reports Server (NTRS)
Eaton, L. R.
1974-01-01
The Zero-Gravity Atmospheric Cloud Physics Laboratory is a Shuttle/Spacelab payload which will be capable of performing a large range of microphysics experiments. This facility will complement terrestrial cloud physics research by allowing many experiments to be performed which cannot be accomplished within the confines of a terrestrial laboratory. This paper reviews the general Cloud Physics Laboratory concept and the experiment scope. The experimental constraints are given along with details of the proposed equipment. Examples of appropriate experiments range from three-dimensional simulation of the earth and planetary atmosphere and of ocean circulation to cloud electrification processes and the effects of atmospheric pollution materials on microphysical processes.
Three Dimensional Modeling Analysis of the Transpacific Transport of Aerosols During PACDEX
NASA Astrophysics Data System (ADS)
Carmichael, G. R.; Adhikary, B.; Hatch, C.; Kulkarni, S.; Moen, J.; Mena, M.
2007-12-01
Mineral dust and aerosols emitted from Asia are known to traverse long distances across the Pacific Ocean and can reach North America within a few days. A pilot field study, the PACific Dust Experiment (PACDEX), was carried out in April and May of 2007, during the peak East Asian dust emission season. The NSF/NCAR-HIAPER (High Performance Instrumented Airborne Platform for Environmental Research) platform allowed for sampling the evolution of mineral aerosol/pollution plumes and their physical and chemical characteristics as they traverse the Pacific Ocean and interact with the Pacific cloud systems en route to North America in both the upper and lower troposphere. A comprehensive 3-dimensional regional-scale model developed at The University of Iowa (Sulfur Transport dEposition Model, STEM) has been used for the analysis of aerosol interactions to help define key measurement strategies during the mission and to help interpret observations from the HIAPER platform. In this study we will present model aerosol distribution inter-comparison with cloud fields and aircraft observations. Model analysis provides further insight into cloud/pollution/dust interactions as East Asian emissions transit the Pacific Ocean en route to North America. Trajectory analysis and emission markers are used to help understand the air mass history and aerosol aging processes of the aerosols sampled by the HIAPER platform. Estimates of the fluxes of aerosol dust, BC and sulfate due to transpacific transport will also be presented.
Analysis of the Meteorology Associated with the 1997 NASA Glenn Twin Otter Icing Events
NASA Technical Reports Server (NTRS)
Bernstein, Ben C.
2000-01-01
This part of the document contains an analysis of the meteorology associated with the premier icing encounters from the January-March 1997 NASA Twin Otter dataset. The purpose of this analysis is to provide a meteorological context for the aircraft data collected during these flights. For each case, the following data elements are presented: (1) A detailed discussion of the Twin Otter encounter, including locations, liquid water contents, temperatures and microphysical makeup of the clouds and precipitation aloft, (2) Upper-air charts, providing hand-analyzed locations of lows, troughs, ridges, saturated/unsaturated air, temperatures, warm/cold advection, and jet streams, (3) Balloon-borne soundings, providing vertical profiles of temperature, moisture and winds, (4) Infrared satellite data, providing cloud locations and cloud top temperature, (5) 3-hourly surface charts, providing hand-analyzed locations of lows, highs, fronts, precipitation (including type) and cloud cover, (6) Hourly plots of icing pilot reports, providing the icing intensity, icing type, icing altitudes and aircraft type, (7) Hourly, regional radar mosaics, providing fine resolution of the locations of precipitation (including intensity and type), pilot reports of icing (including intensity and type), surface observations of precipitation type and Twin Otter tracks for a one hour window centered on the time of the radar data, and (8) Plots of data from individual NEXRAD radars at times and elevation angles that have been matched to Twin Otter flight locations. Outages occurred in nearly every dataset at some point. All relevant data that was available is presented here. All times are in UTC and all heights are in feet above mean sea level (MSL).
A Molecular Line Survey around Orion at Low Frequencies with the MWA
NASA Astrophysics Data System (ADS)
Tremblay, C. D.; Jones, P. A.; Cunningham, M.; Hurley-Walker, N.; Jordan, C. H.; Tingay, S. J.
2018-06-01
The low-frequency sky may reveal some of the secrets yet to be discovered. Until recently, molecules had never been detected within interstellar clouds at frequencies below 700 MHz. Following the pilot survey toward the Galactic center at 103–133 MHz with the Murchison Widefield Array, we surveyed 400 deg2 centered on the Orion KL nebula from 99 to 170 MHz. Orion is a nearby region of active star formation and known to be a chemically rich environment. In this paper, we present tentative detections of nitric oxide and its isotopologues, singularly deuterated formic acid, molecular oxygen, and several unidentified transitions. The three identified molecules are particularly interesting, as laboratory experiments have suggested that these molecules are precursors to the formation of amines.
NASA Technical Reports Server (NTRS)
1996-01-01
On this second day of the STS-72 mission, the flight crew, Cmdr. Brian Duffy, Pilot Brent W. Jett, and Mission Specialists Leroy Chiao, Daniel T. Barry, Winston E. Scott, and Koichi Wakata (NASDA), awakened to music from the motion picture 'Star Wars.' The crew performed a systems checkout, prepared for the retrieval of the Japanese Space Flyer Unit (SFU), tested the spacesuits for the EVA, and activated some of the secondary experiments. An in-orbit news interview was conducted with the crew via satellite downlinking. Questions asked ranged from the logistics of the mission to the avoidance procedures the Endeavour Orbiter performed to miss hitting the inactive Air Force satellite, nicknamed 'Misty' (MSTI). Earth views included cloud cover, several storm systems, and various land masses with several views of the shuttle's open cargo bay in the foreground.
Contrasting cloud composition between coupled and decoupled marine boundary layer clouds
NASA Astrophysics Data System (ADS)
Wang, Zhen; Mora Ramirez, Marco; Dadashazar, Hossein; MacDonald, Alex B.; Crosbie, Ewan; Bates, Kelvin H.; Coggon, Matthew M.; Craven, Jill S.; Lynch, Peng; Campbell, James R.; Azadi Aghdam, Mojtaba; Woods, Roy K.; Jonsson, Haflidi; Flagan, Richard C.; Seinfeld, John H.; Sorooshian, Armin
2016-10-01
Marine stratocumulus clouds often become decoupled from the vertical layer immediately above the ocean surface. This study contrasts cloud chemical composition between coupled and decoupled marine stratocumulus clouds for dissolved nonwater substances. Cloud water and droplet residual particle composition were measured in clouds off the California coast during three airborne experiments in July-August of separate years (Eastern Pacific Emitted Aerosol Cloud Experiment 2011, Nucleation in California Experiment 2013, and Biological and Oceanic Atmospheric Study 2015). Decoupled clouds exhibited significantly lower air-equivalent mass concentrations in both cloud water and droplet residual particles, consistent with reduced cloud droplet number concentration and subcloud aerosol (Dp > 100 nm) number concentration, owing to detachment from surface sources. Nonrefractory submicrometer aerosol measurements show that coupled clouds exhibit higher sulfate mass fractions in droplet residual particles, owing to more abundant precursor emissions from the ocean and ships. Consequently, decoupled clouds exhibited higher mass fractions of organics, nitrate, and ammonium in droplet residual particles, owing to effects of long-range transport from more distant sources. Sodium and chloride dominated in terms of air-equivalent concentration in cloud water for coupled clouds, and their mass fractions and concentrations exceeded those in decoupled clouds. Conversely, with the exception of sea-salt constituents (e.g., Cl, Na, Mg, and K), cloud water mass fractions of all species examined were higher in decoupled clouds relative to coupled clouds. Satellite and Navy Aerosol Analysis and Prediction System-based reanalysis data are compared with each other, and the airborne data to conclude that limitations in resolving boundary layer processes in a global model prevent it from accurately quantifying observed differences between coupled and decoupled cloud composition.
The cloud chamber as a field diagnostic tool
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clark, A
1967-10-19
This document presents the Pros and Cons of using a cloud chamber for field use. Historical aspects are briefly discussed. A cloud chamber experiment on Midi Mist is described. Plans for fielding an experiment on Hupmobile are presented.
Shallow cumulus rooted in photosynthesis
NASA Astrophysics Data System (ADS)
Vila-Guerau Arellano, J.; Ouwersloot, H.; Horn, G.; Sikma, M.; Jacobs, C. M.; Baldocchi, D.
2014-12-01
We investigate the interaction between plant evapotranspiration, controlled by photosynthesis (for a low vegetation cover by C3 and C4 grasses), and the moist thermals that are responsible for the formation and development of shallow cumulus clouds (SCu). We perform systematic numerical experiments at fine spatial scales using large-eddy simulations explicitly coupled to a plant-physiology model. To break down the complexity of the vegetation-atmospheric system at the diurnal scales, we design the following experiments with increasing complexity: (a) clouds that are transparent to radiation, (b) clouds that shade the surface from the incoming shortwave radiation and (c) plant stomata whose apertures react with an adjustment in time to cloud perturbations. The shading by SCu leads to a strong spatial variability in photosynthesis and the surface energy balance. As a result, experiment (b) simulates SCu that are characterized by less extreme and less skewed values of the liquid water path and cloud-base height. These findings are corroborated by the calculation of characteristics lengths scales of the thermals and clouds using autocorrelation and spectral analysis methods. We find that experiments (a) and (b) are characterized by similar cloud cover evolution, but different cloud population characteristics. Experiment (b), including cloud shading, is characterized by smaller clouds, but closer to each other. By performing a sensitivity analysis on the exchange of water vapor and carbon dioxide at the canopy level, we show that the larger water-use efficiency of C4 grass leads to two opposing effects that directly influence boundary-layer clouds: the thermals below the clouds are more vigorous and deeper driven by a larger buoyancy surface flux (positive effect), but are characterized by less moisture content (negative effect). We conclude that under the investigated mid-latitude atmospheric and well-watered soil conditions, SCu over C4 grass fields is characterized by larger cloud cover and an enhanced liquid water path compared to C3 grass fields.
Design and Implementation of a Cloud Computing Adoption Decision Tool: Generating a Cloud Road.
Bildosola, Iñaki; Río-Belver, Rosa; Cilleruelo, Ernesto; Garechana, Gaizka
2015-01-01
Migrating to cloud computing is one of the current enterprise challenges. This technology provides a new paradigm based on "on-demand payment" for information and communication technologies. In this sense, the small and medium enterprise is supposed to be the most interested, since initial investments are avoided and the technology allows gradual implementation. However, even if the characteristics and capacities have been widely discussed, entry into the cloud is still lacking in terms of practical, real frameworks. This paper aims at filling this gap, presenting a real tool already implemented and tested, which can be used as a cloud computing adoption decision tool. This tool uses diagnosis based on specific questions to gather the required information and subsequently provide the user with valuable information to deploy the business within the cloud, specifically in the form of Software as a Service (SaaS) solutions. This information allows the decision makers to generate their particular Cloud Road. A pilot study has been carried out with enterprises at a local level with a two-fold objective: to ascertain the degree of knowledge on cloud computing and to identify the most interesting business areas and their related tools for this technology. As expected, the results show high interest and low knowledge on this subject and the tool presented aims to readdress this mismatch, insofar as possible.
Design and Implementation of a Cloud Computing Adoption Decision Tool: Generating a Cloud Road
Bildosola, Iñaki; Río-Belver, Rosa; Cilleruelo, Ernesto; Garechana, Gaizka
2015-01-01
Migrating to cloud computing is one of the current enterprise challenges. This technology provides a new paradigm based on “on-demand payment” for information and communication technologies. In this sense, the small and medium enterprise is supposed to be the most interested, since initial investments are avoided and the technology allows gradual implementation. However, even if the characteristics and capacities have been widely discussed, entry into the cloud is still lacking in terms of practical, real frameworks. This paper aims at filling this gap, presenting a real tool already implemented and tested, which can be used as a cloud computing adoption decision tool. This tool uses diagnosis based on specific questions to gather the required information and subsequently provide the user with valuable information to deploy the business within the cloud, specifically in the form of Software as a Service (SaaS) solutions. This information allows the decision makers to generate their particular Cloud Road. A pilot study has been carried out with enterprises at a local level with a two-fold objective: to ascertain the degree of knowledge on cloud computing and to identify the most interesting business areas and their related tools for this technology. As expected, the results show high interest and low knowledge on this subject and the tool presented aims to readdress this mismatch, insofar as possible. PMID:26230400
Integration of High-Performance Computing into Cloud Computing Services
NASA Astrophysics Data System (ADS)
Vouk, Mladen A.; Sills, Eric; Dreher, Patrick
High-Performance Computing (HPC) projects span a spectrum of computer hardware implementations ranging from peta-flop supercomputers, high-end tera-flop facilities running a variety of operating systems and applications, to mid-range and smaller computational clusters used for HPC application development, pilot runs and prototype staging clusters. What they all have in common is that they operate as a stand-alone system rather than a scalable and shared user re-configurable resource. The advent of cloud computing has changed the traditional HPC implementation. In this article, we will discuss a very successful production-level architecture and policy framework for supporting HPC services within a more general cloud computing infrastructure. This integrated environment, called Virtual Computing Lab (VCL), has been operating at NC State since fall 2004. Nearly 8,500,000 HPC CPU-Hrs were delivered by this environment to NC State faculty and students during 2009. In addition, we present and discuss operational data that show that integration of HPC and non-HPC (or general VCL) services in a cloud can substantially reduce the cost of delivering cloud services (down to cents per CPU hour).
Cloud Migration Experiment Configuration and Results
2017-12-01
ARL-TR-8248 ● DEC 2017 US Army Research Laboratory Cloud Migration Experiment Configuration and Results by Michael De Lucia...or reconstruction of the document. ARL-TR-8248 ● DEC 2017 US Army Research Laboratory Cloud Migration Experiment Configuration...and Results by Michael De Lucia Computational and Information Sciences Directorate, ARL Justin Wray and Steven S Collmann ICF International
Wind estimates from cloud motions: Phase 1 of an in situ aircraft verification experiment
NASA Technical Reports Server (NTRS)
Hasler, A. F.; Shenk, W. E.; Skillman, W.
1974-01-01
An initial experiment was conducted to verify geostationary satellite derived cloud motion wind estimates with in situ aircraft wind velocity measurements. Case histories of one-half hour to two hours were obtained for 3-10km diameter cumulus cloud systems on 6 days. Also, one cirrus cloud case was obtained. In most cases the clouds were discrete enough that both the cloud motion and the ambient wind could be measured with the same aircraft Inertial Navigation System (INS). Since the INS drift error is the same for both the cloud motion and wind measurements, the drift error subtracts out of the relative motion determinations. The magnitude of the vector difference between the cloud motion and the ambient wind at the cloud base averaged 1.2 m/sec. The wind vector at higher levels in the cloud layer differed by about 3 m/sec to 5 m/sec from the cloud motion vector.
NASA Technical Reports Server (NTRS)
Wilcox, Eric M.; Roberts, Greg; Ramanathan, V.
2006-01-01
Aerosols over the Northeastern Pacific Ocean enhance the cloud drop number concentration and reduce the drop size for marine stratocumulus and cumulus clouds. These microphysical effects result in brighter clouds, as evidenced by a combination of aircraft and satellite observations. In-situ measurements from the Cloud Indirect Forcing Experiment (CIFEX) indicate that the mean cloud drop number concentration in low clouds over the polluted marine boundary layer is greater by 53/cu cm compared to clean clouds, and the mean cloud drop effective radius is smaller by 4 microns. We link these in-situ measurements of cloud modification by aerosols, for the first time, with collocated satellite broadband radiative flux observations from the Clouds and the Earth's Radiant Energy System (CERES) to show that these microphysical effects of aerosols enhance the top-of-atmosphere cooling by -9.9+/-4.3 W/sq m for overcast conditions.
Could geoengineering research help answer one of the biggest questions in climate science?
NASA Astrophysics Data System (ADS)
Wood, Robert; Ackerman, Thomas; Rasch, Philip; Wanser, Kelly
2017-07-01
Anthropogenic aerosol impacts on clouds constitute the largest source of uncertainty in quantifying the radiative forcing of climate, and hinders our ability to determine Earth's climate sensitivity to greenhouse gas increases. Representation of aerosol-cloud interactions in global models is particularly challenging because these interactions occur on typically unresolved scales. Observational studies show influences of aerosol on clouds, but correlations between aerosol and clouds are insufficient to constrain aerosol forcing because of the difficulty in separating aerosol and meteorological impacts. In this commentary, we argue that this current impasse may be overcome with the development of approaches to conduct control experiments whereby aerosol particle perturbations can be introduced into patches of marine low clouds in a systematic manner. Such cloud perturbation experiments constitute a fresh approach to climate science and would provide unprecedented data to untangle the effects of aerosol particles on cloud microphysics and the resulting reflection of solar radiation by clouds. The control experiments would provide a critical test of high-resolution models that are used to develop an improved representation aerosol-cloud interactions needed to better constrain aerosol forcing in global climate models.
14 CFR 61.57 - Recent flight experience: Pilot in command.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Recent flight experience: Pilot in command....57 Recent flight experience: Pilot in command. (a) General experience. (1) Except as provided in paragraph (e) of this section, no person may act as a pilot in command of an aircraft carrying passengers or...
14 CFR 61.57 - Recent flight experience: Pilot in command.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Recent flight experience: Pilot in command....57 Recent flight experience: Pilot in command. (a) General experience. (1) Except as provided in paragraph (e) of this section, no person may act as a pilot in command of an aircraft carrying passengers or...
14 CFR 61.57 - Recent flight experience: Pilot in command.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Recent flight experience: Pilot in command....57 Recent flight experience: Pilot in command. (a) General experience. (1) Except as provided in paragraph (e) of this section, no person may act as a pilot in command of an aircraft carrying passengers or...
14 CFR 61.57 - Recent flight experience: Pilot in command.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Recent flight experience: Pilot in command....57 Recent flight experience: Pilot in command. (a) General experience. (1) Except as provided in paragraph (e) of this section, no person may act as a pilot in command of an aircraft carrying passengers or...
14 CFR 61.57 - Recent flight experience: Pilot in command.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Recent flight experience: Pilot in command....57 Recent flight experience: Pilot in command. (a) General experience. (1) Except as provided in paragraph (e) of this section, no person may act as a pilot in command of an aircraft carrying passengers or...
NASA Astrophysics Data System (ADS)
Rasch, Philip J.; Wood, Robert; Ackerman, Thomas P.
2017-04-01
Anthropogenic aerosol impacts on clouds constitute the largest source of uncertainty in radiative forcing of climate, confounding estimates of climate sensitivity to increases in greenhouse gases. Projections of future warming are also thus strongly dependent on estimates of aerosol effects on clouds. I will discuss the opportunities for improving estimates of aerosol effects on clouds from controlled field experiments where aerosol with well understood size, composition, amount, and injection altitude could be introduced to deliberately change cloud properties. This would allow scientific investigation to be performed in a manner much closer to a lab environment, and facilitate the use of models to predict cloud responses ahead of time, testing our understanding of aerosol cloud interactions.
Additional confirmation of the validity of laboratory simulation of cloud radiances
NASA Technical Reports Server (NTRS)
Davis, J. M.; Cox, S. K.
1986-01-01
The results of a laboratory experiment are presented that provide additional verification of the methodology adopted for simulation of the radiances reflected from fields of optically thick clouds using the Cloud Field Optical Simulator (CFOS) at Colorado State University. The comparison of these data with their theoretically derived counterparts indicates that the crucial mechanism of cloud-to-cloud radiance field interaction is accurately simulated in the CFOS experiments and adds confidence to the manner in which the optical depth is scaled.
Learning and Design with Online Real-Time Collaboration
ERIC Educational Resources Information Center
Stevenson, Michael; Hedberg, John G.
2013-01-01
This paper explores the use of emerging Cloud technologies that support real-time online collaboration. It considers the extent to which these technologies can be leveraged to develop complex skillsets supporting interaction between multiple learners in online spaces. In a pilot study that closely examines how groups of learners translate two…
NASA Technical Reports Server (NTRS)
Eaton, L. R.; Greco, E. V.
1973-01-01
The experiment program definition and preliminary laboratory concept studies on the zero G cloud physics laboratory are reported. This program involves the definition and development of an atmospheric cloud physics laboratory and the selection and delineations of a set of candidate experiments that must utilize the unique environment of zero gravity or near zero gravity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McFarquhar, Greg
We proposed to analyze in-situ cloud data collected during ARM/ASR field campaigns to create databases of cloud microphysical properties and their uncertainties as needed for the development of improved cloud parameterizations for models and remote sensing retrievals, and for evaluation of model simulations and retrievals. In particular, we proposed to analyze data collected over the Southern Great Plains (SGP) during the Mid-latitude Continental Convective Clouds Experiment (MC3E), the Storm Peak Laboratory Cloud Property Validation Experiment (STORMVEX), the Small Particles in Cirrus (SPARTICUS) Experiment and the Routine AAF Clouds with Low Optical Water Depths (CLOWD) Optical Radiative Observations (RACORO) field campaign,more » over the North Slope of Alaska during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) and the Mixed-Phase Arctic Cloud Experiment (M-PACE), and over the Tropical Western Pacific (TWP) during The Tropical Warm Pool International Cloud Experiment (TWP-ICE), to meet the following 3 objectives; derive statistical databases of single ice particle properties (aspect ratio AR, dominant habit, mass, projected area) and distributions of ice crystals (size distributions SDs, mass-dimension m-D, area-dimension A-D relations, mass-weighted fall speeds, single-scattering properties, total concentrations N, ice mass contents IWC), complete with uncertainty estimates; assess processes by which aerosols modulate cloud properties in arctic stratus and mid-latitude cumuli, and quantify aerosol’s influence in context of varying meteorological and surface conditions; and determine how ice cloud microphysical, single-scattering and fall-out properties and contributions of small ice crystals to such properties vary according to location, environment, surface, meteorological and aerosol conditions, and develop parameterizations of such effects.In this report we describe the accomplishments that we made on all 3 research objectives.« less
NASA Astrophysics Data System (ADS)
Shane, Nancy R.
The purpose of this study was to determine how a pilot's educational background, aeronautical experience and recency of experience relate to their performance during initial training at a regional airline. Results show that variables in pilots' educational background, aeronautical experience and recency of experience do predict performance in training. The most significant predictors include years since graduation from college, multi-engine time, total time and whether or not a pilot had military flying experience. Due to the pilot shortage, the pilots entering regional airline training classes since August 2013 have varied backgrounds, aeronautical experience and recency of experience. As explained by Edward Thorndike's law of exercise and the law of recency, pilots who are actively using their aeronautical knowledge and exercising their flying skills should exhibit strong performance in those areas and pilots who have not been actively using their aeronautical knowledge and exercising their flying skills should exhibit degraded performance in those areas. Through correlation, chi-square and multiple regression analysis, this study tests this theory as it relates to performance in initial training at a regional airline.
Photogrammetric retrieval of volcanic ash cloud top height from SEVIRI and MODIS
NASA Astrophysics Data System (ADS)
Zakšek, Klemen; Hort, Matthias; Zaletelj, Janez; Langmann, Bärbel
2013-04-01
Even if erupting in remote areas, volcanoes can have a significant impact on the modern society due to volcanic ash dispersion in the atmosphere. The ash does not affect merely air traffic - its transport in the atmosphere and its deposition on land and in the oceans may also significantly influence the climate through modifications of atmospheric CO2. The emphasis of this contribution is the retrieval of volcanic ash plume height (ACTH). ACTH is important information especially for air traffic but also to predict ash transport and to estimate the mass flux of the ejected material. ACTH is usually estimated from ground measurements, pilot reports, or satellite remote sensing. But ground based instruments are often not available at remote volcanoes and also the pilots reports are a matter of chance. Volcanic ash cloud top height (ACTH) can be monitored on the global level using satellite remote sensing. The most often used method compares brightness temperature of the cloud with the atmospheric temperature profile. Because of uncertainties of this method (unknown emissivity of the ash cloud, tropopause, etc.) we propose photogrammetric methods based on the parallax between data retrieved from geostationary (SEVIRI) and polar orbiting satellites (MODIS). The parallax is estimated using automatic image matching in three level image pyramids. The procedure works well if the data from both satellites are retrieved nearly simultaneously. MODIS does not retrieve the data at exactly the same time as SEVIRI. To compensate for advection we use two sequential SEVIRI images (one before and one after the MODIS retrieval) and interpolate the cloud position from SEVIRI data to the time of MODIS retrieval. ACTH is then estimated by intersection of corresponding lines-of-view from MODIS and interpolated SEVIRI data. The proposed method was tested using MODIS band 1 and SEVIRI HRV band for the case of the Eyjafjallajökull eruption in April 2010. The parallax between MODIS and SEVIRI data can reach over 30 km which implies ACTH of more than 12 km. The accuracy of ACTH was estimated to 0.6 km. The limitation of this procedure is that it has difficulties with automatic image matching if the ash cloud is not opaque.
Toward Measuring Galactic Dense Molecular Gas Properties and 3D Distribution with Hi-GAL
NASA Astrophysics Data System (ADS)
Zetterlund, Erika; Glenn, Jason; Maloney, Phil
2016-01-01
The Herschel Space Observatory's submillimeter dust continuum survey Hi-GAL provides a powerful new dataset for characterizing the structure of the dense interstellar medium of the Milky Way. Hi-GAL observed a 2° wide strip covering the entire 360° of the Galactic plane in broad bands centered at 70, 160, 250, 350, and 500 μm, with angular resolution ranging from 10 to 40 arcseconds. We are adapting a molecular cloud clump-finding algorithm and a distance probability density function distance-determination method developed for the Bolocam Galactic Plane Survey (BGPS) to the Hi-GAL data. Using these methods we expect to generate a database of 105 cloud clumps, derive distance information for roughly half the clumps, and derive precise distances for approximately 20% of them. With five-color photometry and distances, we will measure the cloud clump properties, such as luminosities, physical sizes, and masses, and construct a three-dimensional map of the Milky Way's dense molecular gas distribution.The cloud clump properties and the dense gas distribution will provide critical ground truths for comparison to theoretical models of molecular cloud structure formation and galaxy evolution models that seek to emulate spiral galaxies. For example, such models cannot resolve star formation and use prescriptive recipes, such as converting a fixed fraction of interstellar gas to stars at a specified interstellar medium density threshold. The models should be compared to observed dense molecular gas properties and galactic distributions.As a pilot survey to refine the clump-finding and distance measurement algorithms developed for BGPS, we have identified molecular cloud clumps in six 2° × 2° patches of the Galactic plane, including one in the inner Galaxy along the line of sight through the Molecular Ring and the termination of the Galactic bar and one toward the outer Galaxy. Distances have been derived for the inner Galaxy clumps and compared to Bolocam Galactic Plane Survey results. We present the pilot survey clump catalog, distances, clump properties, and a comparison to BGPS.
NASA Technical Reports Server (NTRS)
Hollinden, A. B.; Eaton, L. R.; Vaughan, W. W.
1972-01-01
The first results of an ongoing preliminary-concept and detailed-feasibility study of a zero-gravity earth-orbital cloud physics research facility are reviewed. Current planning and thinking are being shaped by two major conclusions of this study: (1) there is a strong requirement for and it is feasible to achieve important and significant research in a zero-gravity cloud physics facility; and (2) some very important experiments can be accomplished with 'off-the-shelf' type hardware by astronauts who have no cloud-physics background; the most complicated experiments may require sophisticated observation and motion subsystems and the astronaut may need graduate level cloud physics training; there is a large number of experiments whose complexity varies between these two extremes.
NASA Technical Reports Server (NTRS)
Greco, R. V.; Eaton, L. R.; Wilkinson, H. C.
1974-01-01
The work is summarized which was accomplished from January 1974 to October 1974 for the Zero-Gravity Atmospheric Cloud Physics Laboratory. The definition and development of an atmospheric cloud physics laboratory and the selection and delineation of candidate experiments that require the unique environment of zero gravity or near zero gravity are reported. The experiment program and the laboratory concept for a Spacelab payload to perform cloud microphysics research are defined. This multimission laboratory is planned to be available to the entire scientific community to utilize in furthering the basic understanding of cloud microphysical processes and phenomenon, thereby contributing to improved weather prediction and ultimately to provide beneficial weather control and modification.
Konishi, Yuki; Hayashi, Hiroaki; Takegami, Kazuki; Fukuda, Ikuma; Ueno, Junji
2014-01-01
A cloud chamber is a detector that can visualize the tracks of charged particles. Hayashi, et al. suggested a visualization experiment in which X-rays generated by diagnostic X-ray equipment were directed into a cloud chamber; however, there was a problem in that the wall of the cloud chamber scattered the incoming X-rays. In this study, we developed a new cloud chamber with entrance windows. Because these windows are made of thin film, we were able to direct the X-rays through them without contamination by scattered X-rays from the cloud chamber wall. We have newly proposed an experiment in which beta-particles emitted from radioisotopes are directed into a cloud chamber. We place shielding material in the cloud chamber and visualize the various shielding effects seen with the material positioned in different ways. During the experiment, electrons scattered in the air were measured quantitatively using GM counters. We explained the physical phenomena in the cloud chamber using Monte Carlo simulation code EGS5. Because electrons follow a tortuous path in air, the shielding material must be placed appropriately to be able to effectively block their emissions. Visualization of the tracks of charged particles in this experiment proved effective for instructing not only trainee radiological technologists but also different types of healthcare professionals.
Downward shortwave surface irradiance from 17 sites for the FIRE/SRB Wisconsin experiment
NASA Technical Reports Server (NTRS)
Whitlock, Charles H.; Hay, John E.; Robinson, David A.; Cox, Stephen K.; Wardle, David I.; Lecroy, Stuart R.
1990-01-01
A field experiment was conducted in Wisconsin during Oct. to Nov. 1986 for purposes of both intensive cirrus cloud measurments and SRB algorithm validation activities. The cirrus cloud measurements were part of the FIRE. Tables are presented which show data from 17 sites in the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment/Surface Radiation Budget (FIRE/SRB) Wisconsin experiment region. A discussion of intercomparison results and calibration inconsistencies is also included.
NASA Astrophysics Data System (ADS)
Freer, J. E.; Bloomfield, J. P.; Johnes, P. J.; MacLeod, C.; Reaney, S.
2010-12-01
There are many challenges in developing effective and integrated catchment management solutions for hydrology and water quality issues. Such solutions should ideally build on current scientific evidence to inform policy makers and regulators and additionally allow stakeholders to take ownership of local and/or national issues, in effect bringing together ‘communities of practice’. A strategy being piloted in the UK as the Pilot Virtual Observatory (pVO), funded by NERC, is to demonstrate the use of cyber-infrastructure and cloud computing resources to investigate better methods of linking data and models and to demonstrate scenario analysis for research, policy and operational needs. The research will provide new ways the scientific and stakeholder communities come together to exploit current environmental information, knowledge and experience in an open framework. This poster presents the project scope and methodologies for the pVO work dealing with national modelling of hydrology and macro-nutrient biogeochemistry. We evaluate the strategies needed to robustly benchmark our current predictive capability of these resources through ensemble modelling. We explore the use of catchment similarity concepts to understand if national monitoring programs can inform us about the behaviour of catchments. We discuss the challenges to applying these strategies in an open access and integrated framework and finally we consider the future for such virtual observatory platforms for improving the way we iteratively improve our understanding of catchment science.
14 CFR 135.247 - Pilot qualifications: Recent experience.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Pilot qualifications: Recent experience... Flight Crewmember Requirements § 135.247 Pilot qualifications: Recent experience. (a) No certificate holder may use any person, nor may any person serve, as pilot in command of an aircraft carrying...
14 CFR 135.247 - Pilot qualifications: Recent experience.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Pilot qualifications: Recent experience... Flight Crewmember Requirements § 135.247 Pilot qualifications: Recent experience. (a) No certificate holder may use any person, nor may any person serve, as pilot in command of an aircraft carrying...
NASA Technical Reports Server (NTRS)
Starr, D. OC.; Cox, S. K.
1985-01-01
A simplified cirrus cloud model is presented which may be used to investigate the role of various physical processes in the life cycle of a cirrus cloud. The model is a two-dimensional, time-dependent, Eulerian numerical model where the focus is on cloud-scale processes. Parametrizations are developed to account for phase changes of water, radiative processes, and the effects of microphysical structure on the vertical flux of ice water. The results of a simulation of a thin cirrostratus cloud are given. The results of numerical experiments performed with the model are described in order to demonstrate the important role of cloud-scale processes in determining the cloud properties maintained in response to larger scale forcing. The effects of microphysical composition and radiative processes are considered, as well as their interaction with thermodynamic and dynamic processes within the cloud. It is shown that cirrus clouds operate in an entirely different manner than liquid phase stratiform clouds.
Cloud Statistics for NASA Climate Change Studies
NASA Technical Reports Server (NTRS)
Wylie, Donald P.
1999-01-01
The Principal Investigator participated in two field experiments and developed a global data set on cirrus cloud frequency and optical depth to aid the development of numerical models of climate. Four papers were published under this grant. The accomplishments are summarized: (1) In SUCCESS (SUbsonic aircraft: Contrail & Cloud Effects Special Study) the Principal Investigator aided weather forecasters in the start of the field program. A paper also was published on the clouds studied in SUCCESS and the use of the satellite stereographic technique to distinguish cloud forms and heights of clouds. (2) In SHEBA (Surface Heat Budget in the Arctic) FIRE/ACE (Arctic Cloud Experiment) the Principal Investigator provided daily weather and cloud forecasts for four research aircraft crews, NASA's ER-2, UCAR's C-130, University of Washington's Convert 580, and the Canadian Atmospheric Environment Service's Convert 580. Approximately 105 forecasts were written. The Principal Investigator also made daily weather summaries with calculations of air trajectories for 54 flight days in the experiment. The trajectories show where the air sampled during the flights came from and will be used in future publications to discuss the origin and history of the air and clouds sampled by the aircraft. A paper discussing how well the FIRE/ACE data represent normal climatic conditions in the arctic is being prepared. (3) The Principal Investigator's web page became the source of information for weather forecasting by the scientists on the SHEBA ship. (4) Global Cirrus frequency and optical depth is a continuing analysis of global cloud cover and frequency distribution are being made from the NOAA polar orbiting weather satellites. This analysis is sensitive to cirrus clouds because of the radiative channels used. During this grant three papers were published which describe cloud frequencies, their optical properties and compare the Wisconsin FM Cloud Analysis to other global cloud data such as the International Satellite Cloud Climatology Program (ISCCP) and the Stratospheric Aerosol and Gas Experiment (SAGE). A summary of eight years of HIRS data will be published in late 1998. Important information from this study are: 1) cirrus clouds cover most of the earth, 2) they are found about 40% of the time globally, 3) in the tropics cirrus cloud frequencies are even higher, from 80-100%, 4) there is slight evidence that cirnis cloud cover is increasing in the northern hemisphere at about 0.5% per year, and 5) cirrus clouds have an average infrared transmittance of about 40% of the terrestrial radiation. (5) Global Cloud Frequency Statistics published on the Principal Investigator's web page have been used in the planning of the future CRYSTAL experiment and have been used for refinements of a global numerical model operated at the Colorado State University.
Proceedings of a Workshop on Polar Stratospheric Clouds: Their Role in Atmospheric Processes
NASA Technical Reports Server (NTRS)
Hamill, P. (Editor); Mcmaster, L. R. (Editor)
1984-01-01
The potential role of polar stratospheric clouds in atmospheric processes was assessed. The observations of polar stratospheric clouds with the Nimbus 7 SAM II satellite experiment were reviewed and a preliminary analysis of their formation, impact on other remote sensing experiments, and potential impact on climate were presented. The potential effect of polar stratospheric clouds on climate, radiation balance, atmospheric dynamics, stratospheric chemistry and water vapor budget, and cloud microphysics was assessed. Conclusions and recommendations, a synopsis of materials and complementary material to support those conclusions and recommendations are presented.
A numerical cloud model for the support of laboratory experimentation
NASA Technical Reports Server (NTRS)
Hagen, D. E.
1979-01-01
A numerical cloud model is presented which can describe the evolution of a cloud starting from moist aerosol-laden air through the diffusional growth regime. The model is designed for the direct support of cloud chamber laboratory experimentation, i.e., experiment preparation, real-time control and data analysis. In the model the thermodynamics is uncoupled from the droplet growth processes. Analytic solutions for the cloud droplet growth equations are developed which can be applied in most laboratory situations. The model is applied to a variety of representative experiments.
14 CFR 121.439 - Pilot qualification: Recent experience.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Pilot qualification: Recent experience. 121... Pilot qualification: Recent experience. (a) No certificate holder may use any person nor may any person serve as a required pilot flight crewmember, unless within the preceding 90 days, that person has made...
14 CFR 121.439 - Pilot qualification: Recent experience.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Pilot qualification: Recent experience. 121... Pilot qualification: Recent experience. (a) No certificate holder may use any person nor may any person serve as a required pilot flight crewmember, unless within the preceding 90 days, that person has made...
14 CFR 125.285 - Pilot qualifications: Recent experience.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Pilot qualifications: Recent experience... Requirements § 125.285 Pilot qualifications: Recent experience. (a) No certificate holder may use any person, nor may any person serve, as a required pilot flight crewmember unless within the preceding 90...
14 CFR 125.285 - Pilot qualifications: Recent experience.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Pilot qualifications: Recent experience... Requirements § 125.285 Pilot qualifications: Recent experience. (a) No certificate holder may use any person, nor may any person serve, as a required pilot flight crewmember unless within the preceding 90...
Cruise Report: South China Sea Upper Slope Sand Dunes Project, May 8-14, 2013
2013-06-01
survey of the experimental area in 2012, a pilot experiment in 2013, and the main experiment in 2014. The pilot experiment was carried out during May...8-14 using two Taiwanese research vessels, R/V OCEAN RESEARCHER 5 (OR5) and R/V OCEAN RESEARCHER 2 (OR2). The pilot experiment successfully...design as well as logistical planning for the main experiment . This cruise report documents the operations during the pilot experiment and the data
NASA Technical Reports Server (NTRS)
Purgold, Gerald C.; Wheeler, Robert J.; Whitlock, Charles H.
1992-01-01
Tables and figures are presented which show local site observations of cloud fractions, the number of cloud layers, direction of movement, and precipitation data collected during the FIRE (First ISCCP Regional Experiment) Phase 2 Cirrus Intensive Field Observations (IFO) conducted in Coffeyville, Kansas during November and December, 1991. Selected data are also presented at the times of the TIROS Operational Vertical Sounder (TOVS) satellite overpass. Several major scientific projects have used surface-based observations of clouds to compare directly with those being observed from satellites. Characterizing the physical properties of clouds is extremely useful in obtaining a more accurate analysis of the effect of clouds and their movements on weather and climate. It is the purpose of this paper to report data collected during the FIRE Phase 2 IFO experiment and to provide a brief history of such a surface-based system and the technical information required for recording local cloud parameters.
NASA Technical Reports Server (NTRS)
Minnis, Patrick; Smith, William L., Jr.; Bedka, Kristopher M.; Nguyen, Louis; Palikonda, Rabindra; Hong, Gang; Trepte, Qing Z.; Chee, Thad; Scarino, Benjamin; Spangenberg, Douglas A.;
2014-01-01
Cloud properties determined from satellite imager radiances provide a valuable source of information for nowcasting and weather forecasting. In recent years, it has been shown that assimilation of cloud top temperature, optical depth, and total water path can increase the accuracies of weather analyses and forecasts. Aircraft icing conditions can be accurately diagnosed in near--real time (NRT) retrievals of cloud effective particle size, phase, and water path, providing valuable data for pilots. NRT retrievals of surface skin temperature can also be assimilated in numerical weather prediction models to provide more accurate representations of solar heating and longwave cooling at the surface, where convective initiation. These and other applications are being exploited more frequently as the value of NRT cloud data become recognized. At NASA Langley, cloud properties and surface skin temperature are being retrieved in near--real time globally from both geostationary (GEO) and low--earth orbiting (LEO) satellite imagers for weather model assimilation and nowcasting for hazards such as aircraft icing. Cloud data from GEO satellites over North America are disseminated through NCEP, while those data and global LEO and GEO retrievals are disseminated from a Langley website. This paper presents an overview of the various available datasets, provides examples of their application, and discusses the use of the various datasets downstream. Future challenges and areas of improvement are also presented.
NASA Astrophysics Data System (ADS)
Minnis, P.; Smith, W., Jr.; Bedka, K. M.; Nguyen, L.; Palikonda, R.; Hong, G.; Trepte, Q.; Chee, T.; Scarino, B. R.; Spangenberg, D.; Sun-Mack, S.; Fleeger, C.; Ayers, J. K.; Chang, F. L.; Heck, P. W.
2014-12-01
Cloud properties determined from satellite imager radiances provide a valuable source of information for nowcasting and weather forecasting. In recent years, it has been shown that assimilation of cloud top temperature, optical depth, and total water path can increase the accuracies of weather analyses and forecasts. Aircraft icing conditions can be accurately diagnosed in near-real time (NRT) retrievals of cloud effective particle size, phase, and water path, providing valuable data for pilots. NRT retrievals of surface skin temperature can also be assimilated in numerical weather prediction models to provide more accurate representations of solar heating and longwave cooling at the surface, where convective initiation. These and other applications are being exploited more frequently as the value of NRT cloud data become recognized. At NASA Langley, cloud properties and surface skin temperature are being retrieved in near-real time globally from both geostationary (GEO) and low-earth orbiting (LEO) satellite imagers for weather model assimilation and nowcasting for hazards such as aircraft icing. Cloud data from GEO satellites over North America are disseminated through NCEP, while those data and global LEO and GEO retrievals are disseminated from a Langley website. This paper presents an overview of the various available datasets, provides examples of their application, and discusses the use of the various datasets downstream. Future challenges and areas of improvement are also presented.
Discovery touches down after successful mission STS-95
NASA Technical Reports Server (NTRS)
1998-01-01
Orbiter Discovery touches down in a cloud of smoke on runway 33 at the Shuttle Landing Facility. Discovery returns to Earth with its crew of seven after successfully completing mission STS-95, lasting nearly nine days and 3.6 million miles. The crew members are Mission Commander Curtis L. Brown Jr., Pilot Steven W. Lindsey, Mission Specialist Scott E. Parazynski, Mission Specialist Stephen K. Robinson, Payload Specialist John H. Glenn Jr., senator from Ohio, Mission Specialist Pedro Duque, with the European Space Agency (ESA), and Payload Specialist Chiaki Mukai, with the National Space Development Agency of Japan (NASDA). The mission included research payloads such as the Spartan solar- observing deployable spacecraft, the Hubble Space Telescope Orbital Systems Test Platform, the International Extreme Ultraviolet Hitchhiker, as well as the SPACEHAB single module with experiments on space flight and the aging process.
NASA Astrophysics Data System (ADS)
Smith, William L., Jr.
The threat for aircraft icing in clouds is a significant hazard that routinely impacts aviation operations. Accurate diagnoses and forecasts of aircraft icing conditions requires identifying the location and vertical distribution of clouds with super-cooled liquid water (SLW) droplets, as well as the characteristics of the droplet size distribution. Traditional forecasting methods rely on guidance from numerical models and conventional observations, neither of which currently resolve cloud properties adequately on the optimal scales needed for aviation. Satellite imagers provide measurements over large areas with high spatial resolution that can be interpreted to identify the locations and characteristics of clouds, including features associated with adverse weather and storms. This thesis develops new techniques for interpreting cloud products derived from satellite data to infer the flight icing threat to aircraft in a wide range of cloud conditions. For unobscured low clouds, the icing threat is determined using empirical relationships developed from correlations between satellite imager retrievals of liquid water path and droplet size with icing conditions reported by pilots (PIREPS). For deep ice over water cloud systems, ice and liquid water content profiles are derived by using the imager cloud properties to constrain climatological information on cloud vertical structure and water phase obtained apriori from radar and lidar observations, and from cloud model analyses. Retrievals of the SLW content embedded within overlapping clouds are mapped to the icing threat using guidance from an airfoil modeling study. Compared to PIREPS, the satellite icing detection and intensity accuracies are found to be about 90% and 70%, respectively. Mean differences between the imager IWC retrievals with those from CloudSat and Calipso are less than 30%. This level of closure in the cloud water budget can only be achieved by correcting for errors in the imager retrievals due to the simplifying but poor assumption that deep optically thick clouds are single-phase and vertically homogeneous. When applied to geostationary satellite data, the profiling method provides a real-time characterization of clouds in 4-D. This research should improve the utility of satellite imager data for quantitatively diagnosing and predicting clouds and their effects in weather and climate applications.
NASA Technical Reports Server (NTRS)
Nguyen, Louis; Minnis, Patrick; Spangenberg, Douglas A.; Nordeen, Michele L.; Palikonda, Rabindra; Khaiyer, Mandana M.; Gultepe, Ismail; Reehorst, Andrew L.
2004-01-01
Satellites are ideal for continuous monitoring of aircraft icing conditions in many situations over extensive areas. The satellite imager data are used to diagnose a number of cloud properties that can be used to develop icing intensity indices. Developing and validating these indices requires comparison with objective "cloud truth" data in addition to conventional pilot reports (PIREPS) of icing conditions. Minnis et al. examined the relationships between PIREPS icing and satellite-derived cloud properties. The Atlantic-THORPEX Regional Campaign (ATReC) and the second Alliance Icing Research Study (AIRS-II) field programs were conducted over the northeastern USA and southeastern Canada during late 2003 and early 2004. The aircraft and surface measurements are concerned primarily with the icing characteristics of clouds and, thus, are ideal for providing some validation information for the satellite remote sensing product. This paper starts the process of comparing cloud properties and icing indices derived from the Geostationary Operational Environmental Satellite (GOES) with the aircraft in situ measurements of several cloud properties during campaigns and some of the The comparisons include cloud phase, particle size, icing intensity, base and top altitudes, temperatures, and liquid water path. The results of this study are crucial for developing a more reliable and objective icing product from satellite data. This icing product, currently being derived from GOES data over the USA, is an important complement to more conventional products based on forecasts, and PIREPS.
NASA Technical Reports Server (NTRS)
Hasler, A. F.; Shenk, W. E.; Skillman, W. C.
1975-01-01
Low level aircraft equipped with Inertial Navigation Systems (INS) were used to define the vertical extent and horizontal motion of a cloud and to measure the ambient wind field. A high level aircraft, also equipped with an INS, took photographs to describe the horizontal extent of the cloud field and to measure cloud motion. The aerial photographs were also used to make a positive identification in a satellite picture of the cloud observed by the low level aircraft. The experiment was conducted over the tropical oceans in the vicinity of Florida, Puerto Rico, Panama and in the Western Gulf of Mexico. Results for tropical cumulus clouds indicate excellent agreement between the cloud motion and the wind at the cloud base. The magnitude of the vector difference between the cloud motion and the cloud base wind is less than 1.3 m/sec for 67% of the cases with track lengths of 1 hour or longer. The cirrus cloud motions agreed best with the mean wind in the cloud layer with a vector difference of about 1.6 m/sec.
Use of Cloud Computing to Calibrate a Highly Parameterized Model
NASA Astrophysics Data System (ADS)
Hayley, K. H.; Schumacher, J.; MacMillan, G.; Boutin, L.
2012-12-01
We present a case study using cloud computing to facilitate the calibration of a complex and highly parameterized model of regional groundwater flow. The calibration dataset consisted of many (~1500) measurements or estimates of static hydraulic head, a high resolution time series of groundwater extraction and disposal rates at 42 locations and pressure monitoring at 147 locations with a total of more than one million raw measurements collected over a ten year pumping history, and base flow estimates at 5 surface water monitoring locations. This modeling project was undertaken to assess the sustainability of groundwater withdrawal and disposal plans for insitu heavy oil extraction in Northeast Alberta, Canada. The geological interpretations used for model construction were based on more than 5,000 wireline logs collected throughout the 30,865 km2 regional study area (RSA), and resulted in a model with 28 slices, and 28 hydro stratigraphic units (average model thickness of 700 m, with aquifers ranging from a depth of 50 to 500 m below ground surface). The finite element FEFLOW model constructed on this geological interpretation had 331,408 nodes and required 265 time steps to simulate the ten year transient calibration period. This numerical model of groundwater flow required 3 hours to run on a on a server with two, 2.8 GHz processers and 16 Gb. RAM. Calibration was completed using PEST. Horizontal and vertical hydraulic conductivity as well as specific storage for each unit were independent parameters. For the recharge and the horizontal hydraulic conductivity in the three aquifers with the most transient groundwater use, a pilot point parameterization was adopted. A 7*7 grid of pilot points was defined over the RSA that defined a spatially variable horizontal hydraulic conductivity or recharge field. A 7*7 grid of multiplier pilot points that perturbed the more regional field was then superimposed over the 3,600 km2 local study area (LSA). The pilot point multipliers were implemented so a higher resolution of spatial variability could be obtained where there was a higher density of observation data. Five geologic boundaries were modeled with a specified flux boundary condition and the transfer rate was used as an adjustable parameter for each of these boundaries. This parameterization resulted in 448 parameters for calibration. In the project planning stage it was estimated that the calibration might require as much 15,000 hours (1.7 years) of computing. In an effort to complete the calibration in a timely manner, the inversion was parallelized and implemented on as many as 250 computing nodes located on Amazon's EC2 servers. The results of the calibration provided a better fit to the data than previous efforts with homogenous parameters, and the highly parameterized approach facilitated subspace Monte Carlo analysis for predictive uncertainty. This scale of cloud computing is relatively new for the hydrogeology community and at the time of implementation it was believed to be the first implementation of FEFLOW model at this scale. While the experience provided several challenges, the implementation was successful and provides some valuable learning for future efforts.
Helix Nebula and CERN: A Symbiotic approach to exploiting commercial clouds
NASA Astrophysics Data System (ADS)
Barreiro Megino, Fernando H.; Jones, Robert; Kucharczyk, Katarzyna; Medrano Llamas, Ramón; van der Ster, Daniel
2014-06-01
The recent paradigm shift toward cloud computing in IT, and general interest in "Big Data" in particular, have demonstrated that the computing requirements of HEP are no longer globally unique. Indeed, the CERN IT department and LHC experiments have already made significant R&D investments in delivering and exploiting cloud computing resources. While a number of technical evaluations of interesting commercial offerings from global IT enterprises have been performed by various physics labs, further technical, security, sociological, and legal issues need to be address before their large-scale adoption by the research community can be envisaged. Helix Nebula - the Science Cloud is an initiative that explores these questions by joining the forces of three European research institutes (CERN, ESA and EMBL) with leading European commercial IT enterprises. The goals of Helix Nebula are to establish a cloud platform federating multiple commercial cloud providers, along with new business models, which can sustain the cloud marketplace for years to come. This contribution will summarize the participation of CERN in Helix Nebula. We will explain CERN's flagship use-case and the model used to integrate several cloud providers with an LHC experiment's workload management system. During the first proof of concept, this project contributed over 40.000 CPU-days of Monte Carlo production throughput to the ATLAS experiment with marginal manpower required. CERN's experience, together with that of ESA and EMBL, is providing a great insight into the cloud computing industry and highlighted several challenges that are being tackled in order to ease the export of the scientific workloads to the cloud environments.
NASA Technical Reports Server (NTRS)
Rango, A.
1978-01-01
Major snow zones of the western U.S. were selected to test the capability of satellite systems for mapping snowcover in various snow, cloud, climatic, and vegetation regimes. Different satellite snowcover analysis methods used in each area are described along with results.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-05
... Command Experience; Airmen Online Services; Confirmation of Effective Date AGENCY: Federal Aviation... flight experience requirements do not apply to a pilot in command who is employed by a commuter or on-demand operator if the pilot in command is in compliance with the specific pilot in command...
Cloud/climate sensitivity experiments
NASA Technical Reports Server (NTRS)
Roads, J. O.; Vallis, G. K.; Remer, L.
1982-01-01
A study of the relationships between large-scale cloud fields and large scale circulation patterns is presented. The basic tool is a multi-level numerical model comprising conservation equations for temperature, water vapor and cloud water and appropriate parameterizations for evaporation, condensation, precipitation and radiative feedbacks. Incorporating an equation for cloud water in a large-scale model is somewhat novel and allows the formation and advection of clouds to be treated explicitly. The model is run on a two-dimensional, vertical-horizontal grid with constant winds. It is shown that cloud cover increases with decreased eddy vertical velocity, decreased horizontal advection, decreased atmospheric temperature, increased surface temperature, and decreased precipitation efficiency. The cloud field is found to be well correlated with the relative humidity field except at the highest levels. When radiative feedbacks are incorporated and the temperature increased by increasing CO2 content, cloud amounts decrease at upper-levels or equivalently cloud top height falls. This reduces the temperature response, especially at upper levels, compared with an experiment in which cloud cover is fixed.
Relationship between Recent Flight Experience and Pilot Error General Aviation Accidents
NASA Astrophysics Data System (ADS)
Nilsson, Sarah J.
Aviation insurance agents and fixed-base operation (FBO) owners use recent flight experience, as implied by the 90-day rule, to measure pilot proficiency in physical airplane skills, and to assess the likelihood of a pilot error accident. The generally accepted premise is that more experience in a recent timeframe predicts less of a propensity for an accident, all other factors excluded. Some of these aviation industry stakeholders measure pilot proficiency solely by using time flown within the past 90, 60, or even 30 days, not accounting for extensive research showing aeronautical decision-making and situational awareness training decrease the likelihood of a pilot error accident. In an effort to reduce the pilot error accident rate, the Federal Aviation Administration (FAA) has seen the need to shift pilot training emphasis from proficiency in physical airplane skills to aeronautical decision-making and situational awareness skills. However, current pilot training standards still focus more on the former than on the latter. The relationship between pilot error accidents and recent flight experience implied by the FAA's 90-day rule has not been rigorously assessed using empirical data. The intent of this research was to relate recent flight experience, in terms of time flown in the past 90 days, to pilot error accidents. A quantitative ex post facto approach, focusing on private pilots of single-engine general aviation (GA) fixed-wing aircraft, was used to analyze National Transportation Safety Board (NTSB) accident investigation archival data. The data were analyzed using t-tests and binary logistic regression. T-tests between the mean number of hours of recent flight experience of tricycle gear pilots involved in pilot error accidents (TPE) and non-pilot error accidents (TNPE), t(202) = -.200, p = .842, and conventional gear pilots involved in pilot error accidents (CPE) and non-pilot error accidents (CNPE), t(111) = -.271, p = .787, indicate there is no statistically significant relationship between groups. Binary logistic regression indicate that recent flight experience does not reliably distinguish between pilot error and non-pilot error accidents for TPE/TNPE, chi2 = 0.040 (df=1, p = .841) and CPE/CNPE, chi2= 0.074 (df =1, p = .786). Future research could focus on different pilot populations, and to broaden the scope, analyze several years of data.
NASA Astrophysics Data System (ADS)
Breed, D.; Bruintjes, R.; Jensen, T.; Salazar, V.; Fowler, T.
2005-12-01
During the winter and summer seasons of 2001 and 2002, data were collected to assess the efficacy of cloud seeding to enhance precipitation in the United Arab Emirates (UAE). The results of the feasibility study concluded: 1) that winter clouds in the UAE rarely produced conditions amenable to hygroscopic cloud seeding; 2) that summer convective clouds developed often enough, particularly over the Oman Mountains (e.g., the Hajar Mountains along the eastern UAE border and into Oman) to justify a randomized seeding experiment; 3) that collecting quantitative radar observations continues to be a complex but essential part of evaluating a cloud seeding experiment; 4) that successful flight operations would require solving several logistical issues; and 5) that several scientific questions would need to be studied in order to fully evaluate the efficacy and feasibility of hygroscopic cloud seeding, including cloud physical responses, radar-derived rainfall estimates as related to rainfall at the ground, and hydrological impacts. Based on these results, the UAE program proceeded through the design and implemention of a randomized hygroscopic cloud seeding experiment during the summer seasons to statistically quantify the potential for cloud seeding to enhance rainfall, specifically over the UAE and Oman Mountains, while collecting concurrent and separate physical measurements to support the statistical results and provide substantiation for the physical hypothesis. The randomized seeding experiment was carried out over the summers of 2003 and 2004, and a total of 134 cases were treated over the two summer seasons, of which 96 met the analysis criteria established in the experimental design of the program. The statistical evaluation of these cases yielded largely inconclusive results. Evidence will show that the thermodynamic profile had a large influence on storm characteristics and on precipitation development. This in turn provided a confounding factor in the conduct of the seeding experiment, particularly in the lateness of treatment in the storm cycle. The prevalence of capping inversions and the sensitivity of clouds to the level of the inversions as well as to wind shear will be shown using several data sets (soundings, aircraft, radar, numerical models). Concurrent physical measurements with the randomized experiment provided new insights into the physical processes of precipitation that developed in summertime convective clouds over the UAE that in turn helped in the interpretation of the statistical results.
Variability of Aerosol and its Impact on Cloud Properties Over Different Cities of Pakistan
NASA Astrophysics Data System (ADS)
Alam, Khan
Interaction between aerosols and clouds is the subject of considerable scientific research, due to the importance of clouds in controlling climate. Aerosols vary in time in space and can lead to variations in cloud microphysics. This paper is a pilot study to examine the temporal and spatial variation of aerosol particles and their impact on different cloud optical properties in the territory of Pakistan using the Moderate resolution Imaging Spectroradiometer (MODIS) on board NASA's Terra satellite data and Multi-angle Imaging Spectroradiometer (MISR) data. We also use Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model for trajectory analysis to obtain origin of air masses in order to understand the spatial and temporal variability of aerosol concentrations. We validate data of MODIS and MISR by using linear correlation and regression analysis, which shows that there is an excellent agreement between data of these instruments. Seasonal study of Aerosol Optical Depth (AOD) shows that maximum value is found in monsoon season (June-August) over all study areas. We analyze the relationships between aerosol optical depth (AOD) and some cloud parameters like water vapor (WV), cloud fraction (CF), cloud top temperature (CTT) and cloud top pressure (CTP). We construct the regional correlation maps and time series plots for aerosol and cloud parameters mandatory for the better understanding of aerosol-cloud interaction. Our analyses show that there is a strong positive correlation between AOD and water vapor in all cities. The correlation between AOD and CF is positive for the cities where the air masses are moist while the correlation is negative for cities where air masses are relatively dry and with lower aerosol abundance. It shows that these correlations depend on meteorological conditions. Similarly as AOD increases Cloud Top Pressure (CTP) is decreasing while Cloud Top Temperature (CTT) is increasing. Key Words: MODIS, MISR, HYSPLIT, AOD, CF, CTP, CTT
Recent observations of lightning discharges from the top of a thundercloud into the clear air above
NASA Technical Reports Server (NTRS)
Vaughan, O. H., Jr.; Vonnegut, B.
1988-01-01
A letter of inquiry to a magazine read by airplane pilots has elicited 15 new observations of a rare form of lightning that comes out of the cloud top, goes up vertically, and terminates in the clear air above. These confirm previous observations showing that this phenomenon usually occurs above very large and energetic thunderclouds. However, small clouds with tops at 15,000 feet have been observed to have this rare form of lightning also. One of the more spectacular observations was made over the severe storm that produced the devastating Xenia, Ohio, tornadoes of April 1965.
NASA Astrophysics Data System (ADS)
Popke, Dagmar; Bony, Sandrine; Mauritsen, Thorsten; Stevens, Bjorn
2015-04-01
Model simulations with state-of-the-art general circulation models reveal a strong disagreement concerning the simulated regional precipitation patterns and their changes with warming. The deviating precipitation response even persists when reducing the model experiment complexity to aquaplanet simulation with forced sea surface temperatures (Stevens and Bony, 2013). To assess feedbacks between clouds and radiation on precipitation responses we analyze data from 5 models performing the aquaplanet simulations of the Clouds On Off Klima Intercomparison Experiment (COOKIE), where the interaction of clouds and radiation is inhibited. Although cloud radiative effects are then disabled, the precipitation patterns among models are as diverse as with cloud radiative effects switched on. Disentangling differing model responses in such simplified experiments thus appears to be key to better understanding the simulated regional precipitation in more standard configurations. By analyzing the local moisture and moist static energy budgets in the COOKIE experiments we investigate likely causes for the disagreement among models. References Stevens, B. & S. Bony: What Are Climate Models Missing?, Science, 2013, 340, 1053-1054
Final Technical Report for Grant # DE-FG02-06ER64169
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dr. Beat Schmid, PI
2007-07-13
The Atmospheric Radiation Measurement (ARM) program is funding this project to improve the methodology of ground-based remote sensing of the vertical distribution of aerosol and cloud optical properties, and their effect on atmospheric radiative transfer. Remotely-sensed and in situ observed aerosol, cloud physical, and optical properties collected during the May 2003 Aerosol Intensive Operational Period (AIOP) and the Aerosol Lidar Validation Experiment (ALIVE), conducted from September 11-22, 2005, are the basis for the investigation. We have used ground-based lidar, airborne sunphotometer and in situ measurements and other data to evaluate the vertical profile of aerosol properties. We have been pursuingmore » research in the following three areas: (1) Aerosol Best Estimate Product--Sensitivity Study: ARM is developing an Aerosol Best Estimate (ABE) Value Added Product (VAP) to provide aerosol optical properties at all times and heights above its sites. The ABE is used as input for the Broadband Heating Rate Profile (BBHRP) VAP, whose output will be used to evaluate the radiative treatment of aerosols and clouds in climate models. ARM has a need to assess how much detail is required for the ABE and if a useful ABE can be derived for the tropical and arctic climate research facilities (CRFs) where only limited aerosol information in the vertical is available. We have been determining the sensitivity of BBHRP to the vertical profile of aerosol optical properties used in ABE. (2) Vertically Resolved Aerosol and Cloud Radiative Properties over the Southern Great Plains (SGP): The AIOP delivered an unprecedented airborne radiometric and in situ data set related to aerosols and clouds. The Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS's) Twin Otter aircraft carried solar pointing, up- and down-looking radiometers (spectral and broadband, visible, and infrared) with the uplooking radiometers mounted on a stabilized platform. We are performing an integrated analysis of the largely unexploited radiometric data set to provide observation-based quantification of the effect of aerosols and clouds on the radiation field. We will link aerosol and cloud properties measured in situ with the observed radiative fluxes using radiative transfer models. This over-determined dataset will provide validation of the BBHRP VAP. (3) Integrated Analysis of Data from the Aerosol Lidar Validation Experiment: The ABE VAP relies on continuous lidar observations to provide the vertical distribution of the aerosols above the ARM sites. The goal of ALIVE, conducted in September 2005, was the validation of the aerosol extinction profiles obtained from the SGP Raman lidar, which has been recently refurbished/updated, and the Micro Pulse Lidar, for which a new algorithm to retrieve aerosol profiles has recently been developed, using the National Aeronautics and Space Administration (NASA) Ames Airborne Tracking 14 channel Sun photometer. We are performing and publishing the integrated analysis of the ALIVE data set.« less
NASA Technical Reports Server (NTRS)
Ackerman, Thomas P.; Lin, Ruei-Fong
1993-01-01
The radiation field over a broken stratocumulus cloud deck is simulated by the Monte Carlo method. We conducted four experiments to investigate the main factor for the observed shortwave reflectively over the FIRE flight 2 leg 5, in which reflectivity decreases almost linearly from the cloud center to cloud edge while the cloud top height and the brightness temperature remain almost constant through out the clouds. From our results, the geometry effect, however, did not contribute significantly to what has been observed. We found that the variation of the volume extinction coefficient as a function of its relative position in the cloud affects the reflectivity efficiently. Additional check of the brightness temperature of each experiment also confirms this conclusion. The cloud microphysical data showed some interesting features. We found that the cloud droplet spectrum is nearly log-normal distributed when the clouds were solid. However, whether the shift of cloud droplet spectrum toward the larger end is not certain. The decrease of number density from cloud center to cloud edges seems to have more significant effects on the optical properties.
Integration of cloud-based storage in BES III computing environment
NASA Astrophysics Data System (ADS)
Wang, L.; Hernandez, F.; Deng, Z.
2014-06-01
We present an on-going work that aims to evaluate the suitability of cloud-based storage as a supplement to the Lustre file system for storing experimental data for the BES III physics experiment and as a backend for storing files belonging to individual members of the collaboration. In particular, we discuss our findings regarding the support of cloud-based storage in the software stack of the experiment. We report on our development work that improves the support of CERN' s ROOT data analysis framework and allows efficient remote access to data through several cloud storage protocols. We also present our efforts providing the experiment with efficient command line tools for navigating and interacting with cloud storage-based data repositories both from interactive sessions and grid jobs.
14 CFR 121.439 - Pilot qualification: Recent experience.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Pilot qualification: Recent experience. 121... Pilot qualification: Recent experience. Link to an amendment published at 78 FR 67841, Nov. 12, 2013. (a... qualification: Recent experience. (f) Deviation authority based upon designation of related aircraft in...
NASA Technical Reports Server (NTRS)
Hunt, R. J.; Wu, S. T.
1976-01-01
The general objectives of the Zero-Gravity Atmospheric Cloud Physics Laboratory Program are to improve the level of knowledge in atmospheric cloud research by placing at the disposal of the terrestrial-bound atmospheric cloud physicist a laboratory that can be operated in the environment of zero-gravity or near zero-gravity. This laboratory will allow studies to be performed without mechanical, aerodynamic, electrical, or other techniques to support the object under study. The inhouse analysis of the Skylab 3 and 4 experiments in dynamics of oscillations, rotations, collisions and coalescence of water droplets under low gravity-environment is presented.
The 1980 stratospheric-tropospheric exchange experiment
NASA Technical Reports Server (NTRS)
Margozzi, A. P. (Editor)
1983-01-01
Data are presented from the Stratospheric-Tropospheric Water Vapor Exchange Experiment. Measurements were made during 11 flights of the NASA U-2 aircraft which provided data from horizontal traverser and samplings in and about the tops of extensive cirrus-anvil clouds produced by overshooting cumulus turrets. Aircraft measurements were made of water vapor, ozone, ambient and cloud top temperature, fluorocarbons, nitrous oxide, nitric acid, aerosols, and ice crystal populations. Balloonsondes were flown about twice daily providing data on ozone, wind fields, pressure and temperature to altitudes near 30 km. Satellite photography provided detailed cloud and cloud top temperature information. Descriptions of individual experiments and detailed compilations of all results are provided.
Atmospheric Science Data Center
2014-03-18
... Regional Experiment (FIRE) - Arctic Cloud Experiment (ACE) was conducted April through July of 1998. It was held in conjunction with ... Heat Budget of the Arctic Ocean (SHEBA) Experiment. The FIRE-ACE focused on all aspects of Arctic cloud systems. The main facility was ...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-04
...--Intersection of Cloud Computing and Mobility Forum and Workshop AGENCY: National Institute of Standards and.../intersection-of-cloud-and-mobility.cfm . SUPPLEMENTARY INFORMATION: NIST hosted six prior Cloud Computing Forum... interoperability, portability, and security, discuss the Federal Government's experience with cloud computing...
CERN Computing in Commercial Clouds
NASA Astrophysics Data System (ADS)
Cordeiro, C.; Field, L.; Garrido Bear, B.; Giordano, D.; Jones, B.; Keeble, O.; Manzi, A.; Martelli, E.; McCance, G.; Moreno-García, D.; Traylen, S.
2017-10-01
By the end of 2016 more than 10 Million core-hours of computing resources have been delivered by several commercial cloud providers to the four LHC experiments to run their production workloads, from simulation to full chain processing. In this paper we describe the experience gained at CERN in procuring and exploiting commercial cloud resources for the computing needs of the LHC experiments. The mechanisms used for provisioning, monitoring, accounting, alarming and benchmarking will be discussed, as well as the involvement of the LHC collaborations in terms of managing the workflows of the experiments within a multicloud environment.
The Mixed-Phase Arctic Cloud Experiment (M-PACE)
NASA Technical Reports Server (NTRS)
Verlinde, J.; Harrington, J. Y.; McFarquhar, G. M.; Yannuzzi, V. T.; Avramov, A.; Greenberg, S.; Johnson, N.; Zhang, G.; Poellot, M. R.; Mather, J. H.;
2007-01-01
The Mixed-Phase Arctic Cloud Experiment (M-PACE) was conducted September 27 through October 22, 2004 on the North Slope of Alaska. The primary objective was to collect a data set suitable to study interactions between microphysics, dynamics and radiative transfer in mixed-phase Arctic clouds. Observations taken during the 1997/1998 Surface Heat and Energy Budget of the Arctic (SHEBA) experiment revealed that Arctic clouds frequently consist of one (or more) liquid layers precipitating ice. M-PACE sought to investigate the physical processes of these clouds utilizing two aircraft (an in situ aircraft to characterize the microphysical properties of the clouds and a remote sensing aircraft to constraint the upwelling radiation) over the Department of Energy s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) on the North Slope of Alaska. The measurements successfully documented the microphysical structure of Arctic mixed-phase clouds, with multiple in situ profiles collected in both single-layer and multi-layer clouds over two ground-based remote sensing sites. Liquid was found in clouds with temperatures down to -30 C, the coldest cloud top temperature below -40 C sampled by the aircraft. Remote sensing instruments suggest that ice was present in low concentrations, mostly concentrated in precipitation shafts, although there are indications of light ice precipitation present below the optically thick single-layer clouds. The prevalence of liquid down to these low temperatures could potentially be explained by the relatively low measured ice nuclei concentrations.
On the remote sensing of cloud properties from satellite infrared sounder data
NASA Technical Reports Server (NTRS)
Yeh, H. Y. M.
1984-01-01
A method for remote sensing of cloud parameters by using infrared sounder data has been developed on the basis of the parameterized infrared transfer equation applicable to cloudy atmospheres. The method is utilized for the retrieval of the cloud height, amount, and emissivity in 11 micro m region. Numerical analyses and retrieval experiments have been carried out by utilizing the synthetic sounder data for the theoretical study. The sensitivity of the numerical procedures to the measurement and instrument errors are also examined. The retrieved results are physically discussed and numerically compared with the model atmospheres. Comparisons reveal that the recovered cloud parameters agree reasonably well with the pre-assumed values. However, for cases when relatively thin clouds and/or small cloud fractional cover within a field of view are present, the recovered cloud parameters show considerable fluctuations. Experiments on the proposed algorithm are carried out utilizing High Resolution Infrared Sounder (HIRS/2) data of NOAA 6 and TIROS-N. Results of experiments show reasonably good comparisons with the surface reports and GOES satellite images.
NASA Technical Reports Server (NTRS)
Goodman, S. J.; Christian, H. J.; Boccippio, D. J.; Koshak, W. J.; Cecil, D. J.; Arnold, James E. (Technical Monitor)
2002-01-01
The ThOR mission uses a lightning mapping sensor in geostationary Earth orbit to provide continuous observations of thunderstorm activity over the Americas and nearby oceans. The link between lightning activity and cloud updrafts is the basis for total lightning observations indicating the evolving convective intensification and decay of storms. ThOR offers a national operational demonstration of the utility of real-time total lightning mapping for earlier and more reliable identification of potentially severe and hazardous storms. Regional pilot projects have already demonstrated that the dominance in-cloud lightning and increasing in-cloud lash rates are known to precede severe weather at the surface by tens of minutes. ThOR is currently planned for launch in 2005 on a commercial or research satellite. Real-time data will be provided to selected NWS Weather Forecast Offices and National Centers (EMC/AWC/SPC) for evaluation.
NASA Astrophysics Data System (ADS)
Feltz, Wayne; Griffin, Sarah; Velden, Christopher; Zipser, Ed; Cecil, Daniel; Braun, Scott
2017-04-01
The purpose of this presentation is to identify in-flight hazards to high-altitude aircraft, namely the Global Hawk. The Global Hawk was used during Septembers 2012-2016 as part of two NASA funded Hurricane Sentinel-3 field campaigns to over-fly hurricanes in the Atlantic Ocean. This talk identifies the cause of severe turbulence experienced over Hurricane Emily (2005) and how a combination of NOAA funded GOES-R algorithm derived cloud top heights/tropical overshooting tops using GOES-13/SEVIRI imager radiances, and lightning information are used to identify areas of potential turbulence for near real-time navigation decision support. Several examples will demonstrate how the Global Hawk pilots remotely received and used real-time satellite derived cloud and lightning detection information to keep the aircraft safely above clouds and avoid regions of potential turbulence.
14 CFR 61.313 - What aeronautical experience must I have to apply for a sport pilot certificate?
Code of Federal Regulations, 2010 CFR
2010-01-01
... apply for a sport pilot certificate? 61.313 Section 61.313 Aeronautics and Space FEDERAL AVIATION... GROUND INSTRUCTORS Sport Pilots § 61.313 What aeronautical experience must I have to apply for a sport... aeronautical experience you must have to apply for a sport pilot certificate: If you are applying for a sport...
Homomorphic encryption experiments on IBM's cloud quantum computing platform
NASA Astrophysics Data System (ADS)
Huang, He-Liang; Zhao, You-Wei; Li, Tan; Li, Feng-Guang; Du, Yu-Tao; Fu, Xiang-Qun; Zhang, Shuo; Wang, Xiang; Bao, Wan-Su
2017-02-01
Quantum computing has undergone rapid development in recent years. Owing to limitations on scalability, personal quantum computers still seem slightly unrealistic in the near future. The first practical quantum computer for ordinary users is likely to be on the cloud. However, the adoption of cloud computing is possible only if security is ensured. Homomorphic encryption is a cryptographic protocol that allows computation to be performed on encrypted data without decrypting them, so it is well suited to cloud computing. Here, we first applied homomorphic encryption on IBM's cloud quantum computer platform. In our experiments, we successfully implemented a quantum algorithm for linear equations while protecting our privacy. This demonstration opens a feasible path to the next stage of development of cloud quantum information technology.
Accident rates for novice glider pilots vs. pilots with experience.
Jarvis, Steve; Harris, Don
2007-12-01
It is a popular notion in gliding that newly soloed pilots have a low accident rate. The intention of this study was to review the support for such a hypothesis from literature and to explore it using UK accident totals and measures of flying exposure. Log sheets from UK gliding clubs were used to estimate flying exposure for inexperienced glider pilots. This was used along with accident data and annual flight statistics for the period 2004-2006 in order to estimate accident rates that could be compared between the pilot groups. The UK accident rate for glider pilots from 2004-2006 was 1 accident in every 3534 launches and 1590 flying hours. The lowest estimated rate for pilots with up to 1 h of experience was 1 accident every 976 launches and 149 h flown. For pilots with up to 10 h of experience the figures were 1 accident in 1274 launches and 503 h. From 2004-2006 UK glider pilots with 10 h or less experience in command had twice the number of accidents per launch and three times as many accidents per hour flown than average for UK glider pilots. Pilots with only 1 h of experience or less were involved in at least 10 times the number of accidents per hour flown than the UK average and had more than 3.5 times the number of accidents per launch.
2015-06-01
embassy bombings in Kenya and Tanzania that killed 225 people. An Islamist spokesman claimed that many nomadic tribesmen, including children, were...remained in the single digits . In September of 2011, Press TV, which is an Iranian news organization, claimed that there had been over 80 drone strikes
Structures observed on the spot radiance fields during the FIRE experiment
NASA Technical Reports Server (NTRS)
Seze, Genevieve; Smith, Leonard; Desbois, Michel
1990-01-01
Three Spot images taken during the FIRE experiment on stratocumulus are analyzed. From this high resolution data detailed observations of the true cloud radiance field may be made. The structure and inhomogeneity of these radiance fields hold important implications for the radiation budget, while the fine scale structure in radiance field provides information on cloud dynamics. Wieliki and Welsh, and Parker et al., have quantified the inhomogeneities of the cumulus clouds through a careful examination of the distribution of cloud (and hole) size as functions of an effective cloud diameter and radiance threshold. Cahalan (1988) has compared for different cloud types of (stratocumulus, fair weather cumulus, convective clouds in the ITCZ) the distributions of clouds (and holes) sizes, the relation between the size and the perimeter of these clouds (and holes), and examining the possibility of scale invariance. These results are extended from LANDSAT resolution (57 m and 30 m) to the Spot resolution (10 m) resolution in the case of boundary layer clouds. Particular emphasis is placed on the statistics of zones of high and low reflectivity as a function of a threshold reflectivity.
Report on the Radar/PIREP Cloud Top Discrepancy Study
NASA Technical Reports Server (NTRS)
Wheeler, Mark M.
1997-01-01
This report documents the results of the Applied Meteorology Unit's (AMU) investigation of inconsistencies between pilot reported cloud top heights and weather radar indicated echo top heights (assumed to be cloud tops) as identified by the 45 Weather Squadron (45WS). The objective for this study is to document and understand the differences in echo top characteristics as displayed on both the WSR-88D and WSR-74C radars and cloud top heights reported by the contract weather aircraft in support of space launch operations at Cape Canaveral Air Station (CCAS), Florida. These inconsistencies are of operational concern since various Launch Commit Criteria (LCC) and Flight Rules (FR) in part describe safe and unsafe conditions as a function of cloud thickness. Some background radar information was presented. Scan strategies for the WSR-74C and WSR-88D were reviewed along with a description of normal radar beam propagation influenced by the Effective Earth Radius Model. Atmospheric conditions prior to and leading up to both launch operations were detailed. Through the analysis of rawinsonde and radar data, atmospheric refraction or bending of the radar beam was identified as the cause of the discrepancies between reported cloud top heights by the contract weather aircraft and those as identified by both radars. The atmospheric refraction caused the radar beam to be further bent toward the Earth than normal. This radar beam bending causes the radar target to be displayed erroneously, with higher cloud top heights and a very blocky or skewed appearance.
Guffanti, Marianne; Schneider, David J.; Wallace, Kristi L.; Hall, Tony; Bensimon, Dov R.; Salinas, Leonard J.
2010-01-01
The extensive volcanic cloud from Kasatochi's 2008 eruption caused widespread disruptions to aviation operations along Pacific oceanic, Canadian, and U.S. air routes. Based on aviation hazard warnings issued by the National Oceanic and Atmospheric Administration, U.S. Geological Survey, the Federal Aviation Administration, and Meteorological Service of Canada, air carriers largely avoided the volcanic cloud over a 5 day period by route modifications and flight cancellations. Comparison of time coincident GOES thermal infrared (TIR) data for ash detection with Ozone Monitoring Instrument (OMI) ultraviolet data for SO2 detection shows congruent areas of ash and gas in the volcanic cloud in the 2 days following onset of ash production. After about 2.5 days, the area of SO2 detected by OMI was more extensive than the area of ash indicated by TIR data, indicating significant ash depletion by fall out had occurred. Pilot reports of visible haze at cruise altitudes over Canada and the northern United States suggested that SO2 gas had converted to sulfate aerosols. Uncertain about the hazard potential of the aging cloud, airlines coped by flying over, under, or around the observed haze layer. Samples from a nondamaging aircraft encounter with Kasatochi's nearly 3 day old cloud contained volcanic silicate particles, confirming that some fine ash is present in predominantly gas clouds. The aircraft's exposure to ash was insufficient to cause engine damage; however, slightly damaging encounters with volcanic clouds from eruptions of Reventador in 2002 and Hekla in 2000 indicate the possibility of lingering hazards associated with old and/or diffuse volcanic clouds.
NASA Astrophysics Data System (ADS)
Kodama, C.; Noda, A. T.; Satoh, M.
2012-06-01
This study presents an assessment of three-dimensional structures of hydrometeors simulated by the NICAM, global nonhydrostatic atmospheric model without cumulus parameterization, using multiple satellite data sets. A satellite simulator package (COSP: the CFMIP Observation Simulator Package) is employed to consistently compare model output with ISCCP, CALIPSO, and CloudSat satellite observations. Special focus is placed on high thin clouds, which are not observable in the conventional ISCCP data set, but can be detected by the CALIPSO observations. For the control run, the NICAM simulation qualitatively captures the geographical distributions of the high, middle, and low clouds, even though the horizontal mesh spacing is as coarse as 14 km. The simulated low cloud is very close to that of the CALIPSO low cloud. Both the CloudSat observations and NICAM simulation show a boomerang-type pattern in the radar reflectivity-height histogram, suggesting that NICAM realistically simulates the deep cloud development process. A striking difference was found in the comparisons of high thin cirrus, showing overestimated cloud and higher cloud top in the model simulation. Several model sensitivity experiments are conducted with different cloud microphysical parameters to reduce the model-observation discrepancies in high thin cirrus. In addition, relationships among clouds, Hadley circulation, outgoing longwave radiation and precipitation are discussed through the sensitivity experiments.
Development of a New Model for Accurate Prediction of Cloud Water Deposition on Vegetation
NASA Astrophysics Data System (ADS)
Katata, G.; Nagai, H.; Wrzesinsky, T.; Klemm, O.; Eugster, W.; Burkard, R.
2006-12-01
Scarcity of water resources in arid and semi-arid areas is of great concern in the light of population growth and food shortages. Several experiments focusing on cloud (fog) water deposition on the land surface suggest that cloud water plays an important role in water resource in such regions. A one-dimensional vegetation model including the process of cloud water deposition on vegetation has been developed to better predict cloud water deposition on the vegetation. New schemes to calculate capture efficiency of leaf, cloud droplet size distribution, and gravitational flux of cloud water were incorporated in the model. Model calculations were compared with the data acquired at the Norway spruce forest at the Waldstein site, Germany. High performance of the model was confirmed by comparisons of calculated net radiation, sensible and latent heat, and cloud water fluxes over the forest with measurements. The present model provided a better prediction of measured turbulent and gravitational fluxes of cloud water over the canopy than the Lovett model, which is a commonly used cloud water deposition model. Detailed calculations of evapotranspiration and of turbulent exchange of heat and water vapor within the canopy and the modifications are necessary for accurate prediction of cloud water deposition. Numerical experiments to examine the dependence of cloud water deposition on the vegetation species (coniferous and broad-leaved trees, flat and cylindrical grasses) and structures (Leaf Area Index (LAI) and canopy height) are performed using the presented model. The results indicate that the differences of leaf shape and size have a large impact on cloud water deposition. Cloud water deposition also varies with the growth of vegetation and seasonal change of LAI. We found that the coniferous trees whose height and LAI are 24 m and 2.0 m2m-2, respectively, produce the largest amount of cloud water deposition in all combinations of vegetation species and structures in the experiments.
Modeled Impact of Cirrus Cloud Increases Along Aircraft Flight Paths
NASA Technical Reports Server (NTRS)
Rind, David; Lonergan, P.; Shah, K.
1999-01-01
The potential impact of contrails and alterations in the lifetime of background cirrus due to subsonic airplane water and aerosol emissions has been investigated in a set of experiments using the GISS GCM connected to a q-flux ocean. Cirrus clouds at a height of 12-15km, with an optical thickness of 0.33, were input to the model "x" percentage of clear-sky occasions along subsonic aircraft flight paths, where x is varied from .05% to 6%. Two types of experiments were performed: one with the percentage cirrus cloud increase independent of flight density, as long as a certain minimum density was exceeded; the other with the percentage related to the density of fuel expenditure. The overall climate impact was similar with the two approaches, due to the feedbacks of the climate system. Fifty years were run for eight such experiments, with the following conclusions based on the stable results from years 30-50 for each. The experiments show that adding cirrus to the upper troposphere results in a stabilization of the atmosphere, which leads to some decrease in cloud cover at levels below the insertion altitude. Considering then the total effect on upper level cloud cover (above 5 km altitude), the equilibrium global mean temperature response shows that altering high level clouds by 1% changes the global mean temperature by 0.43C. The response is highly linear (linear correlation coefficient of 0.996) for high cloud cover changes between 0. 1% and 5%. The effect is amplified in the Northern Hemisphere, more so with greater cloud cover change. The temperature effect maximizes around 10 km (at greater than 40C warming with a 4.8% increase in upper level clouds), again more so with greater warming. The high cloud cover change shows the flight path influence most clearly with the smallest warming magnitudes; with greater warming, the model feedbacks introduce a strong tropical response. Similarly, the surface temperature response is dominated by the feedbacks, and shows little geographical relationship to the high cloud input. Considering whether these effects would be observable, changing upper level cloud cover by as little as 0.4% produces warming greater than 2 standard deviations in the Microwave Sounding Unit (MSU) channels 4, 2 and 2r, in flight path regions and in the subtropics. Despite the simplified nature of these experiments, the results emphasize the sensitivity of the modeled climate to high level cloud cover changes, and thus the potential ability of aircraft to influence climate by altering clouds in the upper troposphere.
Cloud Processing of Secondary Organic Aerosol from Isoprene and Methacrolein Photooxidation.
Giorio, Chiara; Monod, Anne; Brégonzio-Rozier, Lola; DeWitt, Helen Langley; Cazaunau, Mathieu; Temime-Roussel, Brice; Gratien, Aline; Michoud, Vincent; Pangui, Edouard; Ravier, Sylvain; Zielinski, Arthur T; Tapparo, Andrea; Vermeylen, Reinhilde; Claeys, Magda; Voisin, Didier; Kalberer, Markus; Doussin, Jean-François
2017-10-12
Aerosol-cloud interaction contributes to the largest uncertainties in the estimation and interpretation of the Earth's changing energy budget. The present study explores experimentally the impacts of water condensation-evaporation events, mimicking processes occurring in atmospheric clouds, on the molecular composition of secondary organic aerosol (SOA) from the photooxidation of methacrolein. A range of on- and off-line mass spectrometry techniques were used to obtain a detailed chemical characterization of SOA formed in control experiments in dry conditions, in triphasic experiments simulating gas-particle-cloud droplet interactions (starting from dry conditions and from 60% relative humidity (RH)), and in bulk aqueous-phase experiments. We observed that cloud events trigger fast SOA formation accompanied by evaporative losses. These evaporative losses decreased SOA concentration in the simulation chamber by 25-32% upon RH increase, while aqueous SOA was found to be metastable and slowly evaporated after cloud dissipation. In the simulation chamber, SOA composition measured with a high-resolution time-of-flight aerosol mass spectrometer, did not change during cloud events compared with high RH conditions (RH > 80%). In all experiments, off-line mass spectrometry techniques emphasize the critical role of 2-methylglyceric acid as a major product of isoprene chemistry, as an important contributor to the total SOA mass (15-20%) and as a key building block of oligomers found in the particulate phase. Interestingly, the comparison between the series of oligomers obtained from experiments performed under different conditions show a markedly different reactivity. In particular, long reaction times at high RH seem to create the conditions for aqueous-phase processing to occur in a more efficient manner than during two relatively short cloud events.
NASA Technical Reports Server (NTRS)
Li, Xiao-Fan; Sui, C.-H.; Lau, K.-M.; Tao, W.-K.
2004-01-01
Prognostic cloud schemes are increasingly used in weather and climate models in order to better treat cloud-radiation processes. Simplifications are often made in such schemes for computational efficiency, like the scheme being used in the National Centers for Environment Prediction models that excludes some microphysical processes and precipitation-radiation interaction. In this study, sensitivity tests with a 2D cloud resolving model are carried out to examine effects of the excluded microphysical processes and precipitation-radiation interaction on tropical thermodynamics and cloud properties. The model is integrated for 10 days with the imposed vertical velocity derived from the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment. The experiment excluding the depositional growth of snow from cloud ice shows anomalous growth of cloud ice and more than 20% increase of fractional cloud cover, indicating that the lack of the depositional snow growth causes unrealistically large mixing ratio of cloud ice. The experiment excluding the precipitation-radiation interaction displays a significant cooling and drying bias. The analysis of heat and moisture budgets shows that the simulation without the interaction produces more stable upper troposphere and more unstable mid and lower troposphere than does the simulation with the interaction. Thus, the suppressed growth of ice clouds in upper troposphere and stronger radiative cooling in mid and lower troposphere are responsible for the cooling bias, and less evaporation of rain associated with the large-scale subsidence induces the drying in mid and lower troposphere.
NASA Astrophysics Data System (ADS)
Oschlisniok, J.; Tellmann, S.; Pätzold, M.; Häusler, B.; Andert, T.; Bird, M.; Remus, S.
2012-09-01
The planet Venus is shrouded within a roughly 20 km thick cloud layer, which extends from the lower to the middle atmosphere (ca. 50 - 70 km). While the clouds are mostly composed of sulfuric acid droplets, a haze layer of sulfuric acid vapor exists below the clouds. Within the cloud and the sub - cloud region Radio signal strength variations (intensity scintillations) caused by atmospheric waves and a decrease in the signal intensity caused by absorption by H2SO4 are observed by radio occultation experiments. The Venus Express spacecraft is orbiting Venus since 2006. The Radio Science Experiment VeRa probes the atmosphere with radio signals at 3.6 cm (XBand) and 13 cm (S-Band) wavelengths. The disturbance of the radio signal intensity is used to investigate the cloud region with respect to atmospheric waves. The absorption of the signal is used to determine the abundance of H2SO4 near the cloud base. This way a detailed study of the H2SO4 abundance within the cloud and sub - cloud region is possible. Results from the intensity scintillations within the cloud deck are presented and compared with gravity wave studies based on temperature variations inferred from VeRa soundings. Vertical absorptivity profiles and resulting sulfuric acid vapor profiles are presented and compared with previous missions. A distinct latitudinal dependence and a southern northern symmetry are clearly visible.
A Computational Fluid Dynamic Model for a Novel Flash Ironmaking Process
NASA Astrophysics Data System (ADS)
Perez-Fontes, Silvia E.; Sohn, Hong Yong; Olivas-Martinez, Miguel
A computational fluid dynamic model for a novel flash ironmaking process based on the direct gaseous reduction of iron oxide concentrates is presented. The model solves the three-dimensional governing equations including both gas-phase and gas-solid reaction kinetics. The turbulence-chemistry interaction in the gas-phase is modeled by the eddy dissipation concept incorporating chemical kinetics. The particle cloud model is used to track the particle phase in a Lagrangian framework. A nucleation and growth kinetics rate expression is adopted to calculate the reduction rate of magnetite concentrate particles. Benchmark experiments reported in the literature for a nonreacting swirling gas jet and a nonpremixed hydrogen jet flame were simulated for validation. The model predictions showed good agreement with measurements in terms of gas velocity, gas temperature and species concentrations. The relevance of the computational model for the analysis of a bench reactor operation and the design of an industrial-pilot plant is discussed.
1998-11-07
Orbiter Discovery touches down in a cloud of smoke on runway 33 at the Shuttle Landing Facility. Main gear touchdown was at 12:04 p.m. EST, landing on orbit 135. Discovery returns to Earth with its crew of seven after successfully completing mission STS-95, lasting nearly nine days and 3.6 million miles. The crew members are Mission Commander Curtis L. Brown Jr.; Pilot Steven W. Lindsey; Mission Specialist Scott E. Parazynski; Mission Specialist Stephen K. Robinson; Payload Specialist John H. Glenn Jr., a senator from Ohio; Mission Specialist Pedro Duque of Spain, with the European Space Agency (ESA); and Payload Specialist Chiaki Mukai, M.D., with the National Space Development Agency of Japan (NASDA). The mission included research payloads such as the Spartan solar-observing deployable spacecraft, the Hubble Space Telescope Orbital Systems Test Platform, the International Extreme Ultraviolet Hitchhiker, as well as the SPACEHAB single module with experiments on space flight and the aging process
14 CFR 121.439 - Pilot qualification: Recent experience.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Pilot qualification: Recent experience. 121.439 Section 121.439 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Pilot qualification: Recent experience. (a) No certificate holder may use any person nor may any person...
14 CFR 121.439 - Pilot qualification: Recent experience.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Pilot qualification: Recent experience. 121.439 Section 121.439 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Pilot qualification: Recent experience. (a) No certificate holder may use any person nor may any person...
14 CFR 125.285 - Pilot qualifications: Recent experience.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Pilot qualifications: Recent experience. 125.285 Section 125.285 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Requirements § 125.285 Pilot qualifications: Recent experience. (a) No certificate holder may use any person...
14 CFR 125.285 - Pilot qualifications: Recent experience.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Pilot qualifications: Recent experience. 125.285 Section 125.285 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Requirements § 125.285 Pilot qualifications: Recent experience. (a) No certificate holder may use any person...
14 CFR 125.285 - Pilot qualifications: Recent experience.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Pilot qualifications: Recent experience. 125.285 Section 125.285 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Requirements § 125.285 Pilot qualifications: Recent experience. (a) No certificate holder may use any person...
Homogeneous Freezing of Water Droplets and its Dependence on Droplet Size
NASA Astrophysics Data System (ADS)
Schmitt, Thea; Möhler, Ottmar; Höhler, Kristina; Leisner, Thomas
2014-05-01
The formulation and parameterisation of microphysical processes in tropospheric clouds, such as phase transitions, is still a challenge for weather and climate models. This includes the homogeneous freezing of supercooled water droplets, since this is an important process in deep convective systems, where almost pure water droplets may stay liquid until homogeneous freezing occurs at temperatures around 238 K. Though the homogeneous ice nucleation in supercooled water is considered to be well understood, recent laboratory experiments with typical cloud droplet sizes showed one to two orders of magnitude smaller nucleation rate coefficients than previous literature results, including earlier results from experiments with single levitated water droplets and from cloud simulation experiments at the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) facility. This motivated us to re-analyse homogeneous droplet freezing experiments conducted during the previous years at the AIDA cloud chamber. This cloud chamber has a volume of 84m3 and operates under atmospherically relevant conditions within wide ranges of temperature, pressure and humidity, whereby investigations of both tropospheric mixed-phase clouds and cirrus clouds can be realised. By controlled adiabatic expansions, the ascent of an air parcel in the troposphere can be simulated. According to our new results and their comparison to the results from single levitated droplet experiments, the homogeneous freezing of water droplets seems to be a volume-dependent process, at least for droplets as small as a few micrometers in diameter. A contribution of surface induced freezing can be ruled out, in agreement to previous conclusions from the single droplet experiments. The obtained volume nucleation rate coefficients are in good agreement, within error bars, with some previous literature data, including our own results from earlier AIDA experiments, but they do not agree with recently published lower volume nucleation rate coefficients. This contribution will show the results from the re-analysis of AIDA homogeneous freezing experiments with pure water droplets and will discuss the comparison to the literature data.
14 CFR 61.313 - What aeronautical experience must I have to apply for a sport pilot certificate?
Code of Federal Regulations, 2011 CFR
2011-01-01
... apply for a sport pilot certificate? 61.313 Section 61.313 Aeronautics and Space FEDERAL AVIATION... GROUND INSTRUCTORS Sport Pilots § 61.313 What aeronautical experience must I have to apply for a sport... apply for a sport pilot certificate: If you are applying for a sport pilot certificate with . . . Then...
NASA Technical Reports Server (NTRS)
Minnis, Patrick; Alvarez, Joseph M.; Young, David F.; Sassen, Kenneth; Grund, Christian J.
1990-01-01
The First ISCCP Regional Experiment (FIRE) Cirrus Intensive Field Observations (IFO) provide an opportunity to examine the relationships between the satellite observed radiances and various parameters which describe the bulk properties of clouds, such as cloud amount and cloud top height. Lidar derived cloud altitude data, radiosonde data, and satellite observed radiances are used to examine the relationships between visible reflectance, infrared emittance, and cloud top temperatures for cirrus clouds.
Insitu aircraft verification of the quality of satellite cloud winds over oceanic regions
NASA Technical Reports Server (NTRS)
Hasler, A. F.; Skillman, W. C.
1979-01-01
A five year aircraft experiment to verify the quality of satellite cloud winds over oceans using in situ aircraft inertial navigation system wind measurements is presented. The final results show that satellite measured cumulus cloud motions are very good estimators of the cloud base wind for trade wind and subtropical high regions. The average magnitude of the vector differences between the cloud motion and the cloud base wind is given. For cumulus clouds near frontal regions, the cloud motion agreed best with the mean cloud layer wind. For a very limited sample, cirrus cloud motions also most closely followed the mean wind in the cloud layer.
NASA Technical Reports Server (NTRS)
Wu, M.-L.
1985-01-01
In order to develop the remote sensing techniques to infer cloud physical parameters, a multispectral cloud radiometer (MCR) was mounted on a NASA high-altitude aircraft in conjunction with the Cooperative Convective Precipitation Experiment in 1981. The MCR has seven spectral channels, of which three are centered near windows associated with water vapor bands in the near infrared, two are centered near the oxygen A band at 0.76 microns, one is centered at the 1.14-micron water vapor band, and one is centered in the thermal infrared. The reflectance and temperature measured on May 31, 1981, are presented together with theoretical calculations. The results indicate that the MCR produces quality measurements. Therefore several cloud parameters can be derived with good accuracy. The parameters are the cloud-scaled optical thickness, cloud top pressure, volume scattering coefficient, particle thermodynamic phase, effective mean particle size, and cloud-top temperature.
75 FR 6164 - New Pilot Certification Requirements for Air Carrier Operations
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-08
... flightcrew eligibility, training, and qualification requirements should be increased for commercial pilots.... House of Representatives passed bill H.R. 3371, the Airline Safety and Pilot Training and Improvement..., practical training/experience, and experience in a crew environment, are also important. A pilot's skills...
Gustafson, William Jr; Vogelmann, Andrew; Endo, Satoshi; Toto, Tami; Xiao, Heng; Li, Zhijin; Cheng, Xiaoping; Kim, Jinwon; Krishna, Bhargavi
2015-08-31
The Alpha 2 release is the second release from the LASSO Pilot Phase that builds upon the Alpha 1 release. Alpha 2 contains additional diagnostics in the data bundles and focuses on cases from spring-summer 2016. A data bundle is a unified package consisting of LASSO LES input and output, observations, evaluation diagnostics, and model skill scores. LES input include model configuration information and forcing data. LES output includes profile statistics and full domain fields of cloud and environmental variables. Model evaluation data consists of LES output and ARM observations co-registered on the same grid and sampling frequency. Model performance is quantified by skill scores and diagnostics in terms of cloud and environmental variables.
What Goes Up Must Come Down: The Lifecycle of Convective Clouds (492nd Brookhaven Lecture)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jensen, Michael
Some clouds look like cotton balls and others like anvils. Some bring rain, some snow and sleet, and others, just shade. But, whether big and billowy or dark and stormy, clouds affect far more than the weather each day. Armed with measurements of clouds’ updrafts and downdrafts—which resemble airflow in a convection oven—and many other atmospheric interactions, scientists from Brookhaven Lab and other institutions around the world are developing models that are crucial for understanding Earth’s climate and forecasting future climate change. During his lecture, Dr. Jensen provides an overview of the importance of clouds in the Earth’s climate systemmore » before explaining how convective clouds form, grow, and dissipate. His discussion includes findings from the Midlatitude Continental Convective Clouds Experiment (MC3E), a major collaborative experiment between U.S. Department of Energy (DOE) and NASA scientists to document precipitation, clouds, winds, and moisture in 3-D for a holistic view of convective clouds and their environment.« less
Commissioning the CERN IT Agile Infrastructure with experiment workloads
NASA Astrophysics Data System (ADS)
Medrano Llamas, Ramón; Harald Barreiro Megino, Fernando; Kucharczyk, Katarzyna; Kamil Denis, Marek; Cinquilli, Mattia
2014-06-01
In order to ease the management of their infrastructure, most of the WLCG sites are adopting cloud based strategies. In the case of CERN, the Tier 0 of the WLCG, is completely restructuring the resource and configuration management of their computing center under the codename Agile Infrastructure. Its goal is to manage 15,000 Virtual Machines by means of an OpenStack middleware in order to unify all the resources in CERN's two datacenters: the one placed in Meyrin and the new on in Wigner, Hungary. During the commissioning of this infrastructure, CERN IT is offering an attractive amount of computing resources to the experiments (800 cores for ATLAS and CMS) through a private cloud interface. ATLAS and CMS have joined forces to exploit them by running stress tests and simulation workloads since November 2012. This work will describe the experience of the first deployments of the current experiment workloads on the CERN private cloud testbed. The paper is organized as follows: the first section will explain the integration of the experiment workload management systems (WMS) with the cloud resources. The second section will revisit the performance and stress testing performed with HammerCloud in order to evaluate and compare the suitability for the experiment workloads. The third section will go deeper into the dynamic provisioning techniques, such as the use of the cloud APIs directly by the WMS. The paper finishes with a review of the conclusions and the challenges ahead.
NASA Technical Reports Server (NTRS)
Pickering, Kenneth E.; Thompson, Anne M.; Tao, Wei-Kuo; Simpson, Joanne; Scala, John R.
1991-01-01
The role of convection was examined in trace gas transport and ozone production in a tropical dry season squall line sampled on August 3, 1985, during NASA Global Tropospheric Experiment/Amazon Boundary Layer Experiment 2A (NASA GTE/ABLE 2A) in Amazonia, Brazil. Two types of analyses were performed. Transient effects within the cloud are examined with a combination of two-dimensional cloud and one-dimensional photochemical modeling. Tracer analyses using the cloud model wind fields yield a series of cross sections of NO(x), CO, and O3 distribution during the lifetime of the cloud; these fields are used in the photochemical model to compute the net rate of O3 production. At noon, when the cloud was mature, the instantaneous ozone production potential in the cloud is between 50 and 60 percent less than in no-cloud conditions due to reduced photolysis and cloud scavenging of radicals. Analysis of cloud inflows and outflows is used to differentiate between air that is undisturbed and air that has been modified by the storm. These profiles are used in the photochemical model to examine the aftereffects of convective redistribution in the 24-hour period following the storm. Total tropospheric column O3 production changed little due to convection because so little NO(x) was available in the lower troposphere. However, the integrated O3 production potential in the 5- to 13-km layer changed from net destruction to net production as a result of the convection. The conditions of the August 3, 1985, event may be typical of the early part of the dry season in Amazonia, when only minimal amounts of pollution from biomass burning have been transported into the region.
NASA Astrophysics Data System (ADS)
Chambers, L. H.; Taylor, J.; Ellis, T. D.; McCrea, S.; Rogerson, T. M.; Falcon, P.
2016-12-01
In 1997, NASA's Clouds and the Earth's Radiant Energy System (CERES) team began engaging K-12 schools as ground truth observers of clouds. CERES seeks to understand cloud effects on Earth's energy budget; thus accurate detection and characterization of clouds is key. While satellite remote sensing provides global information about clouds, it is limited in time and resolution. Ground observers, on the other hand, can observe clouds at any time of day (and sometimes night), and can see small and thin clouds that are challenging to detect from space. In 2006, two active sensing satellites, CloudSat and CALIPSO, were launched into the A-Train, which already contained 2 CERES instruments on the Aqua spacecraft. The CloudSat team also engaged K-12 schools to observe clouds, through The GLOBE Program, with a specialized observation protocol customized for the narrow radar swath. While providing valuable data for satellite assessment, these activities also engage participants in accessible, authentic science that gets people outdoors, helps them develop observation skills, and is friendly to all ages. The effort has evolved substantially since 1997, adopting new technology to provide a more compelling experience to citizen observers. Those who report within 15 minutes of the passage of a wide range of satellites (Terra, Aqua, CloudSat, CALIPSO, NPP, as well as a number of geostationary satellites) are sent a satellite image centered on their location and are invited to extend the experience beyond simple observation to include analysis of the two different viewpoints. Over the years these projects have collected large amounts of cloud observations from every continent and ocean basin on Earth. A number of studies have been conducted comparing the ground observations to the satellite results. This presentation will provide an overview of those results and also describe plans for a coordinated, thematic cloud observation and data analysis activity going forward.
Antiparticle cloud temperatures for antihydrogen experiments
NASA Astrophysics Data System (ADS)
Bianconi, A.; Charlton, M.; Lodi Rizzini, E.; Mascagna, V.; Venturelli, L.
2017-07-01
A simple rate-equation description of the heating and cooling of antiparticle clouds under conditions typical of those found in antihydrogen formation experiments is developed and analyzed. We include single-particle collisional, radiative, and cloud expansion effects and, from the modeling calculations, identify typical cooling phenomena and trends and relate these to the underlying physics. Some general rules of thumb of use to experimenters are derived.
Cloud computing and validation of expandable in silico livers.
Ropella, Glen E P; Hunt, C Anthony
2010-12-03
In Silico Livers (ISLs) are works in progress. They are used to challenge multilevel, multi-attribute, mechanistic hypotheses about the hepatic disposition of xenobiotics coupled with hepatic responses. To enhance ISL-to-liver mappings, we added discrete time metabolism, biliary elimination, and bolus dosing features to a previously validated ISL and initiated re-validated experiments that required scaling experiments to use more simulated lobules than previously, more than could be achieved using the local cluster technology. Rather than dramatically increasing the size of our local cluster we undertook the re-validation experiments using the Amazon EC2 cloud platform. So doing required demonstrating the efficacy of scaling a simulation to use more cluster nodes and assessing the scientific equivalence of local cluster validation experiments with those executed using the cloud platform. The local cluster technology was duplicated in the Amazon EC2 cloud platform. Synthetic modeling protocols were followed to identify a successful parameterization. Experiment sample sizes (number of simulated lobules) on both platforms were 49, 70, 84, and 152 (cloud only). Experimental indistinguishability was demonstrated for ISL outflow profiles of diltiazem using both platforms for experiments consisting of 84 or more samples. The process was analogous to demonstration of results equivalency from two different wet-labs. The results provide additional evidence that disposition simulations using ISLs can cover the behavior space of liver experiments in distinct experimental contexts (there is in silico-to-wet-lab phenotype similarity). The scientific value of experimenting with multiscale biomedical models has been limited to research groups with access to computer clusters. The availability of cloud technology coupled with the evidence of scientific equivalency has lowered the barrier and will greatly facilitate model sharing as well as provide straightforward tools for scaling simulations to encompass greater detail with no extra investment in hardware.
NASA Astrophysics Data System (ADS)
Loro, Stephen Lee
This study was designed to examine moon illumination, moon angle, cloud cover, sky glow, and Night Vision Goggle (NVG) flight performance to determine possible effects. The research was a causal-comparative design. The sample consisted of 194 Fort Rucker Initial Entry Rotary Wing NVG flight students being observed by 69 NVG Instructor Pilots. The students participated in NVG flight training from September 1992 through January 1993. Data were collected using a questionnaire. Observations were analyzed using a Kruskal-Wallis one-way analysis of variance and a Wilcox matched pairs signed-ranks test for difference. Correlations were analyzed using Pearson's r. The analyses results indicated that performance at high moon illumination levels is superior to zero moon illumination, and in most task maneuvers, superior to >0%--50% moon illumination. No differences were found in performance at moon illumination levels above 50%. Moon angle had no effect on night vision goggle flight performance. Cloud cover and sky glow have selective effects on different maneuvers. For most task maneuvers, cloud cover does not affect performance. Overcast cloud cover had a significant effect on seven of the 14 task maneuvers. Sky glow did not affect eight out of 14 task maneuvers at any level of sky glow.
Interaction of a supernova shock with two interstellar clouds
NASA Astrophysics Data System (ADS)
Hansen, J. F.; McKee, C. F.
2005-10-01
The interaction of supernova shocks and interstellar clouds is an important astrophysical phenomenon since it can result in stellar and planetary formation. Our experiments attempt to simulate this mass-loading as it occurs when a shock passes through interstellar clouds. We drive a strong shock using a 5 kJ laser into a foam-filled cylinder with embedded Al spheres (diameter D=120 μm) simulating interstellar clouds. The density ratio between Al and foam is ˜9. We have previously reported on the interaction between shock and a single cloud, and the ensuing Kelvin-Helmholtz and Widnall instabilities. We now report on experiments under way in which two clouds are placed side by side. Cloud separation (center to center) is either 1.2xD or 1.5xD. Initial results for 1.2xD show that cloud material merges and travels further downstream than in the single cloud case. For 1.5xD, material does not merge, but the clouds tilt toward each other. Work performed under the auspices of the Department of Energy by the Lawrence Livermore National Laboratory under contract number W-7405-ENG-48.
Cloud Infrastructure & Applications - CloudIA
NASA Astrophysics Data System (ADS)
Sulistio, Anthony; Reich, Christoph; Doelitzscher, Frank
The idea behind Cloud Computing is to deliver Infrastructure-as-a-Services and Software-as-a-Service over the Internet on an easy pay-per-use business model. To harness the potentials of Cloud Computing for e-Learning and research purposes, and to small- and medium-sized enterprises, the Hochschule Furtwangen University establishes a new project, called Cloud Infrastructure & Applications (CloudIA). The CloudIA project is a market-oriented cloud infrastructure that leverages different virtualization technologies, by supporting Service-Level Agreements for various service offerings. This paper describes the CloudIA project in details and mentions our early experiences in building a private cloud using an existing infrastructure.
ERIC Educational Resources Information Center
Kahn, Russell L.
2013-01-01
This article develops and applies an analytic matrix for searching and using Web 2.0 resources along a learning continuum based on learning styles. This continuum applies core concepts of cognitive psychology, which places an emphasis on internal processes, such as motivation, thinking, attitudes, and reflection. A pilot study found that access to…
The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6.
NASA Technical Reports Server (NTRS)
Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro; Bony, Sandrine; Bretherton, Christopher S.; Chadwick, Robin; Chepfer, Helene; Douville, Herve; Good, Peter; Kay, Jennifer E.;
2017-01-01
The primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud-climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. However, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions 'How does the Earth system respond to forcing?' and 'What are the origins and consequences of systematic model biases?' and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity. A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in precipitation) and their uncertainties in coupled models arise from the combination of different aspects of CO2 forcing and sea surface warming? CFMIP also proposes a number of additional model outputs in the CMIP DECK, CMIP6 Historical and CMIP6 CFMIP experiments, including COSP simulator outputs and process diagnostics to address the following questions. 1. How well do clouds and other relevant variables simulated by models agree with observations? 2. What physical processes and mechanisms are important for a credible simulation of clouds, cloud feedbacks and cloud adjustments in climate models? 3. Which models have the most credible representations of processes relevant to the simulation of clouds? 4. How do clouds and their changes interact with other elements of the climate system?
Cloud chamber experiments on the origin of ice crystal complexity in cirrus clouds
NASA Astrophysics Data System (ADS)
Schnaiter, Martin; Järvinen, Emma; Vochezer, Paul; Abdelmonem, Ahmed; Wagner, Robert; Jourdan, Olivier; Mioche, Guillaume; Shcherbakov, Valery N.; Schmitt, Carl G.; Tricoli, Ugo; Ulanowski, Zbigniew; Heymsfield, Andrew J.
2016-04-01
This study reports on the origin of small-scale ice crystal complexity and its influence on the angular light scattering properties of cirrus clouds. Cloud simulation experiments were conducted at the AIDA (Aerosol Interactions and Dynamics in the Atmosphere) cloud chamber of the Karlsruhe Institute of Technology (KIT). A new experimental procedure was applied to grow and sublimate ice particles at defined super- and subsaturated ice conditions and for temperatures in the -40 to -60 °C range. The experiments were performed for ice clouds generated via homogeneous and heterogeneous initial nucleation. Small-scale ice crystal complexity was deduced from measurements of spatially resolved single particle light scattering patterns by the latest version of the Small Ice Detector (SID-3). It was found that a high crystal complexity dominates the microphysics of the simulated clouds and the degree of this complexity is dependent on the available water vapor during the crystal growth. Indications were found that the small-scale crystal complexity is influenced by unfrozen H2SO4 / H2O residuals in the case of homogeneous initial ice nucleation. Angular light scattering functions of the simulated ice clouds were measured by the two currently available airborne polar nephelometers: the polar nephelometer (PN) probe of Laboratoire de Métérologie et Physique (LaMP) and the Particle Habit Imaging and Polar Scattering (PHIPS-HALO) probe of KIT. The measured scattering functions are featureless and flat in the side and backward scattering directions. It was found that these functions have a rather low sensitivity to the small-scale crystal complexity for ice clouds that were grown under typical atmospheric conditions. These results have implications for the microphysical properties of cirrus clouds and for the radiative transfer through these clouds.
NASA Astrophysics Data System (ADS)
Chern, J. D.; Tao, W. K.; Lang, S. E.; Matsui, T.; Mohr, K. I.
2014-12-01
Four six-month (March-August 2014) experiments with the Goddard Multi-scale Modeling Framework (MMF) were performed to study the impacts of different Goddard one-moment bulk microphysical schemes and large-scale forcings on the performance of the MMF. Recently a new Goddard one-moment bulk microphysics with four-ice classes (cloud ice, snow, graupel, and frozen drops/hail) has been developed based on cloud-resolving model simulations with large-scale forcings from field campaign observations. The new scheme has been successfully implemented to the MMF and two MMF experiments were carried out with this new scheme and the old three-ice classes (cloud ice, snow graupel) scheme. The MMF has global coverage and can rigorously evaluate microphysics performance for different cloud regimes. The results show MMF with the new scheme outperformed the old one. The MMF simulations are also strongly affected by the interaction between large-scale and cloud-scale processes. Two MMF sensitivity experiments with and without nudging large-scale forcings to those of ERA-Interim reanalysis were carried out to study the impacts of large-scale forcings. The model simulated mean and variability of surface precipitation, cloud types, cloud properties such as cloud amount, hydrometeors vertical profiles, and cloud water contents, etc. in different geographic locations and climate regimes are evaluated against GPM, TRMM, CloudSat/CALIPSO satellite observations. The Goddard MMF has also been coupled with the Goddard Satellite Data Simulation Unit (G-SDSU), a system with multi-satellite, multi-sensor, and multi-spectrum satellite simulators. The statistics of MMF simulated radiances and backscattering can be directly compared with satellite observations to assess the strengths and/or deficiencies of MMF simulations and provide guidance on how to improve the MMF and microphysics.
Introducing Cloud Computing Topics in Curricula
ERIC Educational Resources Information Center
Chen, Ling; Liu, Yang; Gallagher, Marcus; Pailthorpe, Bernard; Sadiq, Shazia; Shen, Heng Tao; Li, Xue
2012-01-01
The demand for graduates with exposure in Cloud Computing is on the rise. For many educational institutions, the challenge is to decide on how to incorporate appropriate cloud-based technologies into their curricula. In this paper, we describe our design and experiences of integrating Cloud Computing components into seven third/fourth-year…
Evaluating the Usage of Cloud-Based Collaboration Services through Teamwork
ERIC Educational Resources Information Center
Qin, Li; Hsu, Jeffrey; Stern, Mel
2016-01-01
With the proliferation of cloud computing for both organizational and educational use, cloud-based collaboration services are transforming how people work in teams. The authors investigated the determinants of the usage of cloud-based collaboration services including teamwork quality, computer self-efficacy, and prior experience, as well as its…
Cloud Technology May Widen Genomic Bottleneck - TCGA
Computational biologist Dr. Ilya Shmulevich suggests that renting cloud computing power might widen the bottleneck for analyzing genomic data. Learn more about his experience with the Cloud in this TCGA in Action Case Study.
A Weibull distribution accrual failure detector for cloud computing.
Liu, Jiaxi; Wu, Zhibo; Wu, Jin; Dong, Jian; Zhao, Yao; Wen, Dongxin
2017-01-01
Failure detectors are used to build high availability distributed systems as the fundamental component. To meet the requirement of a complicated large-scale distributed system, accrual failure detectors that can adapt to multiple applications have been studied extensively. However, several implementations of accrual failure detectors do not adapt well to the cloud service environment. To solve this problem, a new accrual failure detector based on Weibull Distribution, called the Weibull Distribution Failure Detector, has been proposed specifically for cloud computing. It can adapt to the dynamic and unexpected network conditions in cloud computing. The performance of the Weibull Distribution Failure Detector is evaluated and compared based on public classical experiment data and cloud computing experiment data. The results show that the Weibull Distribution Failure Detector has better performance in terms of speed and accuracy in unstable scenarios, especially in cloud computing.
GATECloud.net: a platform for large-scale, open-source text processing on the cloud.
Tablan, Valentin; Roberts, Ian; Cunningham, Hamish; Bontcheva, Kalina
2013-01-28
Cloud computing is increasingly being regarded as a key enabler of the 'democratization of science', because on-demand, highly scalable cloud computing facilities enable researchers anywhere to carry out data-intensive experiments. In the context of natural language processing (NLP), algorithms tend to be complex, which makes their parallelization and deployment on cloud platforms a non-trivial task. This study presents a new, unique, cloud-based platform for large-scale NLP research--GATECloud. net. It enables researchers to carry out data-intensive NLP experiments by harnessing the vast, on-demand compute power of the Amazon cloud. Important infrastructural issues are dealt with by the platform, completely transparently for the researcher: load balancing, efficient data upload and storage, deployment on the virtual machines, security and fault tolerance. We also include a cost-benefit analysis and usage evaluation.
Investigation of methods to produce a uniform cloud of fuel particles in a flame tube
NASA Technical Reports Server (NTRS)
Siegert, Clifford E.; Pla, Frederic G.; Rubinstein, Robert; Niezgoda, Thomas F.; Burns, Robert J.; Johnson, Jerome A.
1990-01-01
The combustion of a uniform, quiescent cloud of 30-micron fuel particles in a flame tube was proposed as a space-based, low-gravity experiment. The subject is the normal- and low-gravity testing of several methods to produce such a cloud, including telescoping propeller fans, air pumps, axial and quadrature acoustical speakers, and combinations of these devices. When operated in steady state, none of the methods produced an acceptably uniform cloud (+ or - 5 percent of the mean concentration), and voids in the cloud were clearly visible. In some cases, severe particle agglomeration was observed; however, these clusters could be broken apart by a short acoustic burst from an axially in-line speaker. Analyses and experiments reported elsewhere suggest that transient, acoustic mixing methods can enhance cloud uniformity while minimizing particle agglomeration.
NASA Astrophysics Data System (ADS)
Panitkin, Sergey; Barreiro Megino, Fernando; Caballero Bejar, Jose; Benjamin, Doug; Di Girolamo, Alessandro; Gable, Ian; Hendrix, Val; Hover, John; Kucharczyk, Katarzyna; Medrano Llamas, Ramon; Love, Peter; Ohman, Henrik; Paterson, Michael; Sobie, Randall; Taylor, Ryan; Walker, Rodney; Zaytsev, Alexander; Atlas Collaboration
2014-06-01
The computing model of the ATLAS experiment was designed around the concept of grid computing and, since the start of data taking, this model has proven very successful. However, new cloud computing technologies bring attractive features to improve the operations and elasticity of scientific distributed computing. ATLAS sees grid and cloud computing as complementary technologies that will coexist at different levels of resource abstraction, and two years ago created an R&D working group to investigate the different integration scenarios. The ATLAS Cloud Computing R&D has been able to demonstrate the feasibility of offloading work from grid to cloud sites and, as of today, is able to integrate transparently various cloud resources into the PanDA workload management system. The ATLAS Cloud Computing R&D is operating various PanDA queues on private and public resources and has provided several hundred thousand CPU days to the experiment. As a result, the ATLAS Cloud Computing R&D group has gained a significant insight into the cloud computing landscape and has identified points that still need to be addressed in order to fully utilize this technology. This contribution will explain the cloud integration models that are being evaluated and will discuss ATLAS' learning during the collaboration with leading commercial and academic cloud providers.
Pilot Domain Task Experience in Night Fatal Helicopter Emergency Medical Service Accidents.
Aherne, Bryan B; Zhang, Chrystal; Newman, David G
2016-06-01
In the United States, accident and fatality rates in helicopter emergency medical service (HEMS) operations increase significantly under nighttime environmentally hazardous operational conditions. Other studies have found pilots' total flight hours unrelated to HEMS accident outcomes. Many factors affect pilots' decision making, including their experience. This study seeks to investigate whether pilot domain task experience (DTE) in HEMS plays a role against likelihood of accidents at night when hazardous operational conditions are entered. There were 32 flights with single pilot nighttime fatal HEMS accidents between 1995 and 2013 with findings of controlled flight into terrain (CFIT) and loss of control (LCTRL) due to spatial disorientation (SD) identified. The HEMS DTE of the pilots were compared with industry survey data. Of the pilots, 56% had ≤2 yr of HEMS experience and 9% had >10 yr of HEMS experience. There were 21 (66%) accidents that occurred in non-visual flight rules (VFR) conditions despite all flights being required to be conducted under VFR. There was a statistically significant increase in accident rates in pilots with <2 and <4 yr HEMS DTE and a statistically significant decrease in accident rates in pilots with >10 yr HEMS DTE. HEMS DTE plays a preventive role against the likelihood of a night operational accident. Pilots with limited HEMS DTE are more likely to make a poor assessment of hazardous conditions at night, and this will place HEMS flight crew at high risk in the VFR night domain.
NASA Astrophysics Data System (ADS)
Sanchez, Kevin J.; Roberts, Gregory C.; Calmer, Radiance; Nicoll, Keri; Hashimshoni, Eyal; Rosenfeld, Daniel; Ovadnevaite, Jurgita; Preissler, Jana; Ceburnis, Darius; O'Dowd, Colin; Russell, Lynn M.
2017-08-01
Top-down and bottom-up aerosol-cloud shortwave radiative flux closures were conducted at the Mace Head Atmospheric Research Station in Galway, Ireland, in August 2015. This study is part of the BACCHUS (Impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding) European collaborative project, with the goal of understanding key processes affecting aerosol-cloud shortwave radiative flux closures to improve future climate predictions and develop sustainable policies for Europe. Instrument platforms include ground-based unmanned aerial vehicles (UAVs)1 and satellite measurements of aerosols, clouds and meteorological variables. The ground-based and airborne measurements of aerosol size distributions and cloud condensation nuclei (CCN) concentration were used to initiate a 1-D microphysical aerosol-cloud parcel model (ACPM). UAVs were equipped for a specific science mission, with an optical particle counter for aerosol distribution profiles, a cloud sensor to measure cloud extinction or a five-hole probe for 3-D wind vectors. UAV cloud measurements are rare and have only become possible in recent years through the miniaturization of instrumentation. These are the first UAV measurements at Mace Head. ACPM simulations are compared to in situ cloud extinction measurements from UAVs to quantify closure in terms of cloud shortwave radiative flux. Two out of seven cases exhibit sub-adiabatic vertical temperature profiles within the cloud, which suggests that entrainment processes affect cloud microphysical properties and lead to an overestimate of simulated cloud shortwave radiative flux. Including an entrainment parameterization and explicitly calculating the entrainment fraction in the ACPM simulations both improved cloud-top radiative closure. Entrainment reduced the difference between simulated and observation-derived cloud-top shortwave radiative flux (δRF) by between 25 and 60 W m-2. After accounting for entrainment, satellite-derived cloud droplet number concentrations (CDNCs) were within 30 % of simulated CDNC. In cases with a well-mixed boundary layer, δRF is no greater than 20 W m-2 after accounting for cloud-top entrainment and up to 50 W m-2 when entrainment is not taken into account. In cases with a decoupled boundary layer, cloud microphysical properties are inconsistent with ground-based aerosol measurements, as expected, and δRF is as high as 88 W m-2, even high (> 30 W m-2) after accounting for cloud-top entrainment. This work demonstrates the need to take in situ measurements of aerosol properties for cases where the boundary layer is decoupled as well as consider cloud-top entrainment to accurately model stratocumulus cloud radiative flux. 1The regulatory term for UAV is remotely piloted aircraft (RPA).
NASA Astrophysics Data System (ADS)
1995-09-01
The highlights of the STS-70 mission are presented in this video. The flight crew consisted of Cmdr. John Hendricks, Pilot Kevin Kregel, Flight Engineer Nancy Curie, and Mission Specialists Dr. Don Thomas and Dr. Mary Ellen Weber. The mission's primary objective was the deployment of the 7th Tracking Data and Relay Satellite (TDRS), which will provide a communication, tracking, telemetry, data acquisition, and command services space-based network system essential to low Earth orbital spacecraft. Secondary mission objectives included activating and studying the Physiological and Anatomical Rodent Experiment/National Institutes of Health-Rodents (PARE/NIH-R), The Bioreactor Demonstration System (BDS), the Commercial Protein Crystal Growth (CPCG) studies, the Space Tissue Loss/National Institutes of Health-Cells (STL/NIH-C) experiment, the Biological Research in Canisters (BRIC) experiment, Shuttle Amateur Radio Experiment-2 (SAREX-2), the Visual Function Tester-4 (VFT-4), the Hand-Held, Earth Oriented, Real-Time, Cooperative, User-Friendly, Location-Targeting and Environmental System (HERCULES), the Microcapsules in Space-B (MIS-B) experiment, the Windows Experiment (WINDEX), the Radiation Monitoring Equipment-3 (RME-3), and the Military Applications of Ship Tracks (MAST) experiment. There was an in-orbit dedication ceremony by the spacecrew and the newly Integrated Mission Control Center to commemorate the Center's integration. The STS-70 mission was the first mission monitored by this new control center. Earth views included the Earth's atmosphere, a sunrise over the Earth's horizon, several views of various land masses, some B/W lightning shots, some cloud cover, and a tropical storm.
Daniel M. Johnson; William K. Smith
2008-01-01
The high altitude spruce-fir (Abies fraseri (Pursh) Poiret.-Picea rubens Sarg.) forests of the southern Appalachian Mountains, USA, experience frequent cloud immersion. Recent studies indicate that cloud bases may have risen over the past 30 years, resulting in less frequent forest cloud immersion, and that further increases in cloud base height are...
The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6
Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro; ...
2017-01-01
Our primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud–climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. But, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions Howmore » does the Earth system respond to forcing? and What are the origins and consequences of systematic model biases? and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity.A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO 2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO 2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in precipitation) and their uncertainties in coupled models arise from the combination of different aspects of CO 2 forcing and sea surface warming?CFMIP also proposes a number of additional model outputs in the CMIP DECK, CMIP6 Historical and CMIP6 CFMIP experiments, including COSP simulator outputs and process diagnostics to address the following questions. How well do clouds and other relevant variables simulated by models agree with observations?What physical processes and mechanisms are important for a credible simulation of clouds, cloud feedbacks and cloud adjustments in climate models?Which models have the most credible representations of processes relevant to the simulation of clouds?How do clouds and their changes interact with other elements of the climate system?« less
The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6
DOE Office of Scientific and Technical Information (OSTI.GOV)
Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro
Our primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud–climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. But, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions Howmore » does the Earth system respond to forcing? and What are the origins and consequences of systematic model biases? and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity.A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO 2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO 2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in precipitation) and their uncertainties in coupled models arise from the combination of different aspects of CO 2 forcing and sea surface warming?CFMIP also proposes a number of additional model outputs in the CMIP DECK, CMIP6 Historical and CMIP6 CFMIP experiments, including COSP simulator outputs and process diagnostics to address the following questions. How well do clouds and other relevant variables simulated by models agree with observations?What physical processes and mechanisms are important for a credible simulation of clouds, cloud feedbacks and cloud adjustments in climate models?Which models have the most credible representations of processes relevant to the simulation of clouds?How do clouds and their changes interact with other elements of the climate system?« less
Norwegian Young Sea Ice Experiment (N-ICE) Field Campaign Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walden, V. P.; Hudson, S. R.; Cohen, L.
The Norwegian Young Sea Ice (N-ICE) experiment was conducted aboard the R/V Lance research vessel from January through June 2015. The primary purpose of the experiment was to better understand thin, first-year sea ice. This includes understanding of how different components of the Arctic system affect sea ice, but also how changing sea ice affects the system. A major part of this effort is to characterize the atmospheric conditions throughout the experiment. A micropulse lidar (MPL) (S/N: 108) was deployed from the U.S. Department of Energy’s (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility as part of the atmospheric suitemore » of instruments. The MPL operated successfully throughout the entire experiment, acquiring data from 21 January 2015 through 23 June 2015. The MPL was the essential instrument for determining the phase (water, ice or mixed) of the lower-level clouds over the sea ice. Data obtained from the MPL during the N-ICE experiment show large cloud fractions over young, thin Arctic sea ice from January through June 2015 (north of Svalbard). The winter season was characterized by frequent synoptic storms and large fluctuations in the near-surface temperature. There was much less synoptic activity in spring and summer as the near-surface temperature rose to 0 C. The cloud fraction was lower in winter (60%) than in the spring and summer (80%). Supercooled liquid clouds were observed for most of the deployment, appearing first in mid-February. Spring and summer clouds were characterized by low, thick, uniform clouds.« less
Volcanic plumes fast detection: a methodological proposal for an integrated approach
NASA Astrophysics Data System (ADS)
Bernabeo, R. Alberto; Tositti, Laura; Brattich, Erika
2017-04-01
The behaviour of erupting volcanoes ranges from the quiet, steady effusion of lava to highly explosive eruptions. Therefore volcanic eruptions may present a direct threat to the safety of aircraft in flight and major operational difficulties at aerodromes and in airspaces located downwind the resulting volcanic ash cloud, in particular when eruptions are of high intensity and/or prolonged. Since volcanic ash clouds and gases are not displayed on either airborne or ATC radar and are extremely difficult to identify at night, pilots must rely on reports from air traffic controllers and from other pilots to determine the location of an ash cloud or gases. As a result, there is a clear need to develop extra tools enabling the timely on-board sensing of volcanic plumes for the sake of safety purposes. Large scale eruptions may eject many cubic kilometres of glass particles and pulverized rock (volcanic ash) as well as corrosive/hazardous gases high into the atmosphere, potentially over a wide area for timescales ranging from hours to weeks or even months. Volcanic ash consists mostly of sharp-edged, hard glass particles and pulverized rock. It is very abrasive and, being largely composed of siliceous materials, has a melting temperature below the operating temperature of modern turbine engines at cruise thrust. A volcanic plume in fact contains a complex mixture of water vapour, sulphur dioxide (producing sulphuric acid as a result of gas-to particle conversions reaction catalysed by iron in cloud droplets), chlorine and other halogens, and trace elements which are highly reactive and may interact with the mineral particles to produce corrosive effects hazardous to both airframes and human health. Remotely piloted aircraft system (RPAS) or Unmanned aerial vehicles (UAV) are slowly becoming efficient platforms - with dedicated miniaturized sensors that can be used in scientific/commercial remote sensing applications - and are of fundamental support to the planning, running and control of the territory in which public safety is or may be at risk, and with reference to all those subjects that require a continuous cyclical process of observation, evaluation and interpretation. At the same time, a better knowledge of the chemical properties of volcanic emissions is a must for the future expansion foreseen in the next coming years in air transportation, for the health hazards that a volcanic ash cloud poses around the world and for a better understanding of the reduction already observed in GPS/GNSS satellite signals anytime a volcanic cloud covers the sky (thus obscuring the signal used by the navigation systems of modern aircraft), with associated safety risks. In this paper we propose a multitasking experimental approach based on the integrated use of remote sensing, aerosol sampling and chemical speciation together with the use of drones/tethered balloons equipped with aerosol sensors aimed at providing all the information which have been collected partially so far. The study will also collect information about the 3D distribution of all the aerosol properties described before with the aim of determining and helping the vertical resolution of data from remote sensing.
Code of Federal Regulations, 2010 CFR
2010-01-01
... apply for a flight instructor certificate with a sport pilot rating? 61.411 Section 61.411 Aeronautics... CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Flight Instructors With a Sport Pilot Rating... sport pilot rating? Use the following table to determine the experience you must have for each aircraft...
Code of Federal Regulations, 2011 CFR
2011-01-01
... apply for a flight instructor certificate with a sport pilot rating? 61.411 Section 61.411 Aeronautics... CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Flight Instructors With a Sport Pilot Rating... sport pilot rating? Use the following table to determine the experience you must have for each aircraft...
Impact of gender, age and experience of pilots on general aviation accidents.
Bazargan, Massoud; Guzhva, Vitaly S
2011-05-01
General aviation (GA) accounts for more than 82% of all air transport-related accidents and air transport-related fatalities in the U.S. In this study, we conduct a series of statistical analyses to investigate the significance of a pilot's gender, age and experience in influencing the risk for pilot errors and fatalities in GA accidents. There is no evidence from the Chi-square tests and logistic regression models that support the likelihood of an accident caused by pilot error to be related to pilot gender. However, evidence is found that male pilots, those older than 60 years of age, and with more experience, are more likely to be involved in a fatal accident. Copyright © 2010 Elsevier Ltd. All rights reserved.
AceCloud: Molecular Dynamics Simulations in the Cloud.
Harvey, M J; De Fabritiis, G
2015-05-26
We present AceCloud, an on-demand service for molecular dynamics simulations. AceCloud is designed to facilitate the secure execution of large ensembles of simulations on an external cloud computing service (currently Amazon Web Services). The AceCloud client, integrated into the ACEMD molecular dynamics package, provides an easy-to-use interface that abstracts all aspects of interaction with the cloud services. This gives the user the experience that all simulations are running on their local machine, minimizing the learning curve typically associated with the transition to using high performance computing services.
NASA Technical Reports Server (NTRS)
Starr, David O'C.; Benedetti, Angela; Boehm, Matt; Brown, Philip R. A.; Gierens, Klaus M.; Girard, Eric; Giraud, Vincent; Jakob, Christian; Jensen, Eric
2000-01-01
The GEWEX Cloud System Study (GCSS, GEWEX is the Global Energy and Water Cycle Experiment) is a community activity aiming to promote development of improved cloud parameterizations for application in the large-scale general circulation models (GCMs) used for climate research and for numerical weather prediction. The GCSS strategy is founded upon the use of cloud-system models (CSMs). These are "process" models with sufficient spatial and temporal resolution to represent individual cloud elements, but spanning a wide range of space and time scales to enable statistical analysis of simulated cloud systems. GCSS also employs single-column versions of the parametric cloud models (SCMs) used in GCMs. GCSS has working groups on boundary-layer clouds, cirrus clouds, extratropical layer cloud systems, precipitating deep convective cloud systems, and polar clouds.
Simple Cloud Chambers Using Gel Ice Packs
ERIC Educational Resources Information Center
Kamata, Masahiro; Kubota, Miki
2012-01-01
Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…
Wood, Robert; Ackerman, Thomas; Rasch, Philip J.; ...
2017-06-22
Anthropogenic aerosol impacts on clouds constitute the largest source of uncertainty in quantifying the radiative forcing of climate, and hinders our ability to determine Earth's climate sensitivity to greenhouse gas increases. Representation of aerosol–cloud interactions in global models is particularly challenging because these interactions occur on typically unresolved scales. Observational studies show influences of aerosol on clouds, but correlations between aerosol and clouds are insufficient to constrain aerosol forcing because of the difficulty in separating aerosol and meteorological impacts. In this commentary, we argue that this current impasse may be overcome with the development of approaches to conduct control experimentsmore » whereby aerosol particle perturbations can be introduced into patches of marine low clouds in a systematic manner. Such cloud perturbation experiments constitute a fresh approach to climate science and would provide unprecedented data to untangle the effects of aerosol particles on cloud microphysics and the resulting reflection of solar radiation by clouds. Here, the control experiments would provide a critical test of high-resolution models that are used to develop an improved representation aerosol–cloud interactions needed to better constrain aerosol forcing in global climate models.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Robert; Ackerman, Thomas; Rasch, Philip J.
Anthropogenic aerosol impacts on clouds constitute the largest source of uncertainty in quantifying the radiative forcing of climate, and hinders our ability to determine Earth's climate sensitivity to greenhouse gas increases. Representation of aerosol–cloud interactions in global models is particularly challenging because these interactions occur on typically unresolved scales. Observational studies show influences of aerosol on clouds, but correlations between aerosol and clouds are insufficient to constrain aerosol forcing because of the difficulty in separating aerosol and meteorological impacts. In this commentary, we argue that this current impasse may be overcome with the development of approaches to conduct control experimentsmore » whereby aerosol particle perturbations can be introduced into patches of marine low clouds in a systematic manner. Such cloud perturbation experiments constitute a fresh approach to climate science and would provide unprecedented data to untangle the effects of aerosol particles on cloud microphysics and the resulting reflection of solar radiation by clouds. Here, the control experiments would provide a critical test of high-resolution models that are used to develop an improved representation aerosol–cloud interactions needed to better constrain aerosol forcing in global climate models.« less
NASA Technical Reports Server (NTRS)
Green, Carolyn J.; Chambers, Lin H.
1998-01-01
The Students Clouds Observations On-Line or S'COOL project was piloted in 1997. It was created with the idea of using students to serve as one component of the validation for the Clouds and the Earth's Radiant Energy System (CERES) instrument which was launched with the Tropical Rainfall Measuring Mission (TRMM) in November, 1997. As part of NASA's Earth Science Enterprise CERES is interested in the role clouds play in regulating our climate. Over thirty schools became involved in the initial thrust of the project. The CERES instrument detects the location of clouds and identifies their physical properties. S'COOL students coordinate their ground truth observations with the exact overpass of the satellite at their location. Their findings regarding cloud type, height, fraction and opacity as well as surface conditions are then reported to the NASA Langley Distributed Active Archive Center (DAAC). The data is then accessible to both the CERES team for validation and to schools for educational application via the Internet. By March of 1998 ninety-three schools, in nine countries had enrolled in the S'COOL project. Joining the United States participants were from schools in Australia, Canada, France, Germany, Norway, Spain, Sweden, and Switzerland. The project is gradually becoming the global project envisioned by the project s creators. As students obtain the requested data useful for the scientists, it was hoped that students with guidance from their instructors would have opportunity and motivation to learn more about clouds and atmospheric science as well.
A Weibull distribution accrual failure detector for cloud computing
Wu, Zhibo; Wu, Jin; Zhao, Yao; Wen, Dongxin
2017-01-01
Failure detectors are used to build high availability distributed systems as the fundamental component. To meet the requirement of a complicated large-scale distributed system, accrual failure detectors that can adapt to multiple applications have been studied extensively. However, several implementations of accrual failure detectors do not adapt well to the cloud service environment. To solve this problem, a new accrual failure detector based on Weibull Distribution, called the Weibull Distribution Failure Detector, has been proposed specifically for cloud computing. It can adapt to the dynamic and unexpected network conditions in cloud computing. The performance of the Weibull Distribution Failure Detector is evaluated and compared based on public classical experiment data and cloud computing experiment data. The results show that the Weibull Distribution Failure Detector has better performance in terms of speed and accuracy in unstable scenarios, especially in cloud computing. PMID:28278229
In-Situ Data for Microphysical Retrievals: TC4, 2007
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mace, Gerald
This data set is derived from measurements collected in situ by the NASA DC8 during the Tropical Cloud Climate Composition Coupling Experiment (TC4) that was conducted during July and August, 2007 (Toon et al., 2010). During this experiment the DC8 was based in San Jose, Costa Rica and sampled clouds in the maritime region of the Eastern Pacific and adjoining continental areas. The primary objective of the DC8 during this deployment was to sample ice clouds associated with convective activity. While the vast majority of the data are from ice-phase clouds that have recent association with convection, other types ofmore » clouds such as boundary layer clouds and active convection were also sampled and are represented in this data set. The derived data set, as compiled in this delivery, includes approximately 15,000 5-second averaged measurements collected by the NASA DC8.« less
Symptoms of fatigue and coping strategies in maritime pilotage.
Chambers, Timothy P; Main, Luana C
2015-01-01
Little is known regarding the symptoms of fatigue that maritime pilots experience during shift work. Moreover, the strategies these individuals use to cope with the onset of fatigue are also unknown. The current study explored the symptoms of fatigue and coping strategies experienced by maritime pilots when on-shift. Fifty maritime pilots were recruited via an advertisement in the national association's quarterly newsletter (Mage = 51.42; SD = 9.81). Participants responded to a modified version of the questionnaire used with aviation pilots that assessed overall fatigue, and the symptoms pilots associated with fatigue on duty. Methods pilots used to cope with fatigue before shift and when on the bridge were also assessed. There were significant effects for pilot vitality on 4 categories of fatigue: cognitive dysfunction; emotional disturbance; mean physical effects; and sleepiness. There were no significant effects for vitality on any of the self-reported coping strategy factors. The findings indicated that maritime pilots experience a variety of physical, behavioural, and cognitive fatigue symptoms when on shift. Some of these symptoms are similar to those reported by aviation pilots. However, unlike aviation pilots, maritime pilots reported utilising self-sufficient coping strategies to deal with the experience of fatigue.
Techniques for the measurements of the line of sight velocity of high altitude Barium clouds
NASA Technical Reports Server (NTRS)
Mende, S. B.
1981-01-01
It is demonstrated that for maximizing the scientific output of future ion cloud release experiments a new type of instrument is required which will measure the line of sight velocity of the ion cloud by the Doppler Technique. A simple instrument was constructed using a 5 cm diameter solid Fabry-Perot etalon coupled to a low light level integrating television camera. It was demonstrated that the system has both the sensitivity and spectral resolution for the detection of ion clouds and the measurement of their line of sight Doppler velocity. The tests consisted of (1) a field experiment using a rocket barium cloud release to check the sensitivity, (2) laboratory experiments to show the spectral resolving capabilities of the system. The instrument was found to be operational if the source was brighter than about 1 kilorayleigh and it had a wavelength resolution much better than .2A which corresponds to about 12 km/sec or an acceleration potential of 100 volts.
Transitioning ISR architecture into the cloud
NASA Astrophysics Data System (ADS)
Lash, Thomas D.
2012-06-01
Emerging cloud computing platforms offer an ideal opportunity for Intelligence, Surveillance, and Reconnaissance (ISR) intelligence analysis. Cloud computing platforms help overcome challenges and limitations of traditional ISR architectures. Modern ISR architectures can benefit from examining commercial cloud applications, especially as they relate to user experience, usage profiling, and transformational business models. This paper outlines legacy ISR architectures and their limitations, presents an overview of cloud technologies and their applications to the ISR intelligence mission, and presents an idealized ISR architecture implemented with cloud computing.
NASA Technical Reports Server (NTRS)
Vali, G.
1982-01-01
A low gravity experiment to assess the effect of the presence of supercooled cloud droplets on the diffusional growth rate of ice crystals is described. The theoretical work and the feasibility studies are summarized. The nucleation of ice crystals in supercooled clouds is also discussed.
Analytical study of the Atmospheric Cloud Physics Laboratory (ACPL) experiments
NASA Technical Reports Server (NTRS)
Davis, M. H.
1977-01-01
The design specifications of the research laboratory as a Spacelab facility are discussed along with the types of planned experiments. These include cloud formation, freezing and scavenging, and electrical phenomena. A summary of the program conferences is included.
NASA Astrophysics Data System (ADS)
Shiobara, M.; Takano, T.; Okamoto, H.; Yabuki, M.
2015-12-01
Clouds and aerosols are key elements having a potential to change climate by their radiative effects on the energy balance in the global climate system. In the Arctic, we have been continuing ground-based remote-sensing measurements for clouds and aerosols using a sky-radiometer, a micro-pulse lidar (MPL) and an all-sky camera in Ny-Ålesund (78.9N, 11.9E), Svalbard since early 2000's. In addition to such regular operations, several new measurements have been performed with a polarization MPL since August 2013, a 95GHz Doppler cloud radar since September 2013, and a dual frequency microwave radiometer since June 2014. An intensive field experiment for cloud-aerosol-radiation interaction study named A-CARE (PI: J. Ukita) was conducted for water clouds in the period of 23 June - 13 July 2014 and for mixed phase clouds in the period of 30 March - 23 April 2015 in Ny-Alesund. The experiment consisted of ground-based remote-sensing and in-situ cloud microphysics measurements. In this paper, preliminary results from these remote-sensing measurements will be presented, particularly in regard to physical characteristics of Arctic clouds based on radar-lidar collocated observation in Ny-Ålesund.
Design of laboratory experiments to study radiation-driven implosions
Keiter, P. A.; Trantham, M.; Malamud, G.; ...
2017-02-03
The interstellar medium is heterogeneous with dense clouds amid an ambient medium. Radiation from young OB stars asymmetrically irradiate the dense clouds. Bertoldi (1989) developed analytic formulae to describe possible outcomes of these clouds when irradiated by hot, young stars. One of the critical parameters that determines the cloud’s fate is the number of photon mean free paths in the cloud. For the extreme cases where the cloud size is either much greater than or much less than one mean free path, the radiation transport should be well understood. However, as one transitions between these limits, the radiation transport ismore » much more complex and is a challenge to solve with many of the current radiation transport models implemented in codes. In this paper, we present the design of laboratory experiments that use a thermal source of x-rays to asymmetrically irradiate a low-density plastic foam sphere. The experiment will vary the density and hence the number of mean free paths of the sphere to study the radiation transport in different regimes. Finally, we have developed dimensionless parameters to relate the laboratory experiment to the astrophysical system and we show that we can perform the experiment in the same transport regime.« less
Measurement of optical blurring in a turbulent cloud chamber
NASA Astrophysics Data System (ADS)
Packard, Corey D.; Ciochetto, David S.; Cantrell, Will H.; Roggemann, Michael C.; Shaw, Raymond A.
2016-10-01
Earth's atmosphere can significantly impact the propagation of electromagnetic radiation, degrading the performance of imaging systems. Deleterious effects of the atmosphere include turbulence, absorption and scattering by particulates. Turbulence leads to blurring, while absorption attenuates the energy that reaches imaging sensors. The optical properties of aerosols and clouds also impact radiation propagation via scattering, resulting in decorrelation from unscattered light. Models have been proposed for calculating a point spread function (PSF) for aerosol scattering, providing a method for simulating the contrast and spatial detail expected when imaging through atmospheres with significant aerosol optical depth. However, these synthetic images and their predicating theory would benefit from comparison with measurements in a controlled environment. Recently, Michigan Technological University (MTU) has designed a novel laboratory cloud chamber. This multiphase, turbulent "Pi Chamber" is capable of pressures down to 100 hPa and temperatures from -55 to +55°C. Additionally, humidity and aerosol concentrations are controllable. These boundary conditions can be combined to form and sustain clouds in an instrumented laboratory setting for measuring the impact of clouds on radiation propagation. This paper describes an experiment to generate mixing and expansion clouds in supersaturated conditions with salt aerosols, and an example of measured imagery viewed through the generated cloud is shown. Aerosol and cloud droplet distributions measured during the experiment are used to predict scattering PSF and MTF curves, and a methodology for validating existing theory is detailed. Measured atmospheric inputs will be used to simulate aerosol-induced image degradation for comparison with measured imagery taken through actual cloud conditions. The aerosol MTF will be experimentally calculated and compared to theoretical expressions. The key result of this study is the proposal of a closure experiment for verification of theoretical aerosol effects using actual clouds in a controlled laboratory setting.
Cloud and boundary layer structure over San Nicolas Island during FIRE
NASA Technical Reports Server (NTRS)
Albrecht, Bruce A.; Fairall, Christopher W.; Syrett, William J.; Schubert, Wayne H.; Snider, Jack B.
1990-01-01
The temporal evolution of the structure of the marine boundary layer and of the associated low-level clouds observed in the vicinity of the San Nicolas Island (SNI) is defined from data collected during the First ISCCP Regional Experiment (FIRE) Marine Stratocumulus Intense Field Observations (IFO) (July 1 to 19). Surface, radiosonde, and remote-sensing measurements are used for this analysis. Sounding from the Island and from the ship Point Sur, which was located approximately 100 km northwest of SNI, are used to define variations in the thermodynamic structure of the lower-troposphere on time scales of 12 hours and longer. Time-height sections of potential temperature and equivalent potential temperature clearly define large-scale variations in the height and the strength of the inversion and periods where the conditions for cloud-top entrainment instability (CTEI) are met. Well defined variations in the height and the strength of the inversion were associated with a Cataline Eddy that was present at various times during the experiment and with the passage of the remnants of a tropical cyclone on July 18. The large-scale variations in the mean thermodynamic structure at SNI correlate well with those observed from the Point Sur. Cloud characteristics are defined for 19 days of the experiment using data from a microwave radiometer, a cloud ceilometer, a sodar, and longwave and shortwave radiometers. The depth of the cloud layer is estimated by defining inversion heights from the sodar reflectivity and cloud-base heights from a laser ceilometer. The integrated liquid water obtained from NOAA's microwave radiometer is compared with the adiabatic liquid water content that is calculated by lifting a parcel adiabatically from cloud base. In addition, the cloud structure is characterized by the variability in cloud-base height and in the integrated liquid water.
NASA Astrophysics Data System (ADS)
Riebeek Kohl, H.; Low, R.; Boger, R. A.; Schwerin, T. G.; Janney, D. W.
2017-12-01
The spread of disease vectors, including mosquitoes, is an increasingly significant global environmental issue driven by a warming climate. In 2017, the GLOBE Observer Program launched a new citizen science initiative to map mosquito habitats using the free GLOBE Observer App for smart phones and tablets. The app guides people to identify mosquito larvae and breeding sites, and then once documented, to eliminate or treat the site to prevent further breeding. It also gives citizen scientists the option to identify the mosquito larvae species to determine whether it is one of three genera that potentially could transmit Zika, dengue fever, yellow fever, chikungunya, and other diseases. This data is uploaded to an international database that is freely available to the public and science community. GLOBE Observer piloted the initiative with educators in the United States, Brazil, and Peru, and it is now open for global participation. This presentation will discuss lessons learned in the pilot phase as well as plans to implement the initiative worldwide in partnership with science museums and science centers. GLOBE Observer is the non-student citizen science arm of the Global Learning and Observations to Benefit the Environment (GLOBE) Program, a long-standing, international science and education program that provides students and citizen scientists with the opportunity to participate in data collection and the scientific process, and contribute meaningfully to our understanding of the Earth system and global environment. GLOBE Observer data collection also includes cloud cover and cloud type and land cover/land use (in late 2017).
The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6
NASA Astrophysics Data System (ADS)
Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro; Bony, Sandrine; Bretherton, Christopher S.; Chadwick, Robin; Chepfer, Hélène; Douville, Hervé; Good, Peter; Kay, Jennifer E.; Klein, Stephen A.; Marchand, Roger; Medeiros, Brian; Pier Siebesma, A.; Skinner, Christopher B.; Stevens, Bjorn; Tselioudis, George; Tsushima, Yoko; Watanabe, Masahiro
2017-01-01
The primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud-climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. However, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions How does the Earth system respond to forcing?
and What are the origins and consequences of systematic model biases?
and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity.A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in precipitation) and their uncertainties in coupled models arise from the combination of different aspects of CO2 forcing and sea surface warming?CFMIP also proposes a number of additional model outputs in the CMIP DECK, CMIP6 Historical and CMIP6 CFMIP experiments, including COSP simulator outputs and process diagnostics to address the following questions.
How well do clouds and other relevant variables simulated by models agree with observations?
What physical processes and mechanisms are important for a credible simulation of clouds, cloud feedbacks and cloud adjustments in climate models?
Which models have the most credible representations of processes relevant to the simulation of clouds?
How do clouds and their changes interact with other elements of the climate system?
Meteorological Input to General Aviation Pilot Training
NASA Technical Reports Server (NTRS)
Colomy, J. R.
1979-01-01
The meteorological education of general aviation pilots is discussed in terms of the definitions and concepts of learning and good educational procedures. The effectiveness of the metoeorological program in the training of general aviations pilots is questioned. It is suggested that flight instructors provide real experience during low ceilings and visibilities, and that every pilot receiving an instrument rating should experience real instrument flight.
Factors Controlling the Properties of Multi-Phase Arctic Stratocumulus Clouds
NASA Technical Reports Server (NTRS)
Fridlind, Ann; Ackerman, Andrew; Menon, Surabi
2005-01-01
The 2004 Multi-Phase Arctic Cloud Experiment (M-PACE) IOP at the ARM NSA site focused on measuring the properties of autumn transition-season arctic stratus and the environmental conditions controlling them, including concentrations of heterogeneous ice nuclei. Our work aims to use a large-eddy simulation (LES) code with embedded size-resolved aerosol and cloud microphysics to identify factors controlling multi-phase arctic stratus. Our preliminary simulations of autumn transition-season clouds observed during the 1994 Beaufort and Arctic Seas Experiment (BASE) indicated that low concentrations of ice nuclei, which were not measured, may have significantly lowered liquid water content and thereby stabilized cloud evolution. However, cloud drop concentrations appeared to be virtually immune to changes in liquid water content, indicating an active Bergeron process with little effect of collection on drop number concentration. We will compare these results with preliminary simulations from October 8-13 during MPACE. The sensitivity of cloud properties to uncertainty in other factors, such as large-scale forcings and aerosol profiles, will also be investigated. Based on the LES simulations with M-PACE data, preliminary results from the NASA GlSS single-column model (SCM) will be used to examine the sensitivity of predicted cloud properties to changing cloud drop number concentrations for multi-phase arctic clouds. Present parametrizations assumed fixed cloud droplet number concentrations and these will be modified using M-PACE data.
NASA Technical Reports Server (NTRS)
Starr, David OC.; Benedetti, Angela; Boehm, Matt; Brown, Philip R. A.; Gierens, Klaus M.; Girard, Eric; Giraud, Vincent; Jakob, Christian; Jensen, Eric; Khvorostyanov, Vitaly;
2000-01-01
The GEWEX Cloud System Study (GCSS, GEWEX is the Global Energy and Water Cycle Experiment) is a community activity aiming to promote development of improved cloud parameterizations for application in the large-scale general circulation models (GCMs) used for climate research and for numerical weather prediction (Browning et al, 1994). The GCSS strategy is founded upon the use of cloud-system models (CSMs). These are "process" models with sufficient spatial and temporal resolution to represent individual cloud elements, but spanning a wide range of space and time scales to enable statistical analysis of simulated cloud systems. GCSS also employs single-column versions of the parametric cloud models (SCMs) used in GCMs. GCSS has working groups on boundary-layer clouds, cirrus clouds, extratropical layer cloud systems, precipitating deep convective cloud systems, and polar clouds.
NASA Technical Reports Server (NTRS)
1981-01-01
The performance of the technology exhibited significant proportion estimation errors, specifically, high mean error in both corn and soybeans area estimation. The data systems, technical approaches, and data assessment of the pilot experiment were reviewed. Results of proportion estimations procedure performance evaluations, and sensitivity evaluations are presented. The role of the pilot experiment in foreign technology development is discussed.
Artificial ionospheric modification: The Metal Oxide Space Cloud experiment
NASA Astrophysics Data System (ADS)
Caton, Ronald G.; Pedersen, Todd R.; Groves, Keith M.; Hines, Jack; Cannon, Paul S.; Jackson-Booth, Natasha; Parris, Richard T.; Holmes, Jeffrey M.; Su, Yi-Jiun; Mishin, Evgeny V.; Roddy, Patrick A.; Viggiano, Albert A.; Shuman, Nicholas S.; Ard, Shaun G.; Bernhardt, Paul A.; Siefring, Carl L.; Retterer, John; Kudeki, Erhan; Reyes, Pablo M.
2017-05-01
Clouds of vaporized samarium (Sm) were released during sounding rocket flights from the Reagan Test Site, Kwajalein Atoll in May 2013 as part of the Metal Oxide Space Cloud (MOSC) experiment. A network of ground-based sensors observed the resulting clouds from five locations in the Republic of the Marshall Islands. Of primary interest was an examination of the extent to which a tailored radio frequency (RF) propagation environment could be generated through artificial ionospheric modification. The MOSC experiment consisted of launches near dusk on two separate evenings each releasing 6 kg of Sm vapor at altitudes near 170 km and 180 km. Localized plasma clouds were generated through a combination of photoionization and chemi-ionization (Sm + O → SmO+ + e-) processes producing signatures visible in optical sensors, incoherent scatter radar, and in high-frequency (HF) diagnostics. Here we present an overview of the experiment payloads, document the flight characteristics, and describe the experimental measurements conducted throughout the 2 week launch window. Multi-instrument analysis including incoherent scatter observations, HF soundings, RF beacon measurements, and optical data provided the opportunity for a comprehensive characterization of the physical, spectral, and plasma density composition of the artificial plasma clouds as a function of space and time. A series of companion papers submitted along with this experimental overview provide more detail on the individual elements for interested readers.
Holtzapple, R. L.; Billing, M. G.; Campbell, R. C.; ...
2016-04-11
Electron cloud related emittance dilution and instabilities of bunch trains limit the performance of high intensity circular colliders. One of the key goals of the Cornell electron-positron storage ring Test Accelerator (CesrTA) research program is to improve our understanding of how the electron cloud alters the dynamics of bunches within the train. Single bunch beam diagnostics have been developed to measure the beam spectra, vertical beam size, two important dynamical effects of beams interacting with the electron cloud, for bunch trains on a turn-by-turn basis. Experiments have been performed at CesrTA to probe the interaction of the electron cloud withmore » stored positron bunch trains. The purpose of these experiments was to characterize the dependence of beam-electron cloud interactions on the machine parameters such as bunch spacing, vertical chromaticity, and bunch current. The beam dynamics of the stored beam, in the presence of the electron cloud, was quantified using: 1) a gated beam position monitor (BPM) and spectrum analyzer to measure the bunch-by-bunch frequency spectrum of the bunch trains, 2) an x-ray beam size monitor to record the bunch-by-bunch, turn-by-turn vertical size of each bunch within the trains. In this study we report on the observations from these experiments and analyze the effects of the electron cloud on the stability of bunches in a train under many different operational conditions.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Minnis, Patrick
2013-06-28
During the period, March 1997 – February 2006, the Principal Investigator and his research team co-authored 47 peer-reviewed papers and presented, at least, 138 papers at conferences, meetings, and workshops that were supported either in whole or in part by this agreement. We developed a state-of-the-art satellite cloud processing system that generates cloud properties over the Atmospheric Radiation (ARM) surface sites and surrounding domains in near-real time and outputs the results on the world wide web in image and digital formats. When the products are quality controlled, they are sent to the ARM archive for further dissemination. These products andmore » raw satellite images can be accessed at http://cloudsgate2.larc.nasa.gov/cgi-bin/site/showdoc?docid=4&cmd=field-experiment-homepage&exp=ARM and are used by many in the ARM science community. The algorithms used in this system to generate cloud properties were validated and improved by the research conducted under this agreement. The team supported, at least, 11 ARM-related or supported field experiments by providing near-real time satellite imagery, cloud products, model results, and interactive analyses for mission planning, execution, and post-experiment scientific analyses. Comparisons of cloud properties derived from satellite, aircraft, and surface measurements were used to evaluate uncertainties in the cloud properties. Multiple-angle satellite retrievals were used to determine the influence of cloud structural and microphysical properties on the exiting radiation field.« less
NASA Astrophysics Data System (ADS)
Holtzapple, R. L.; Billing, M. G.; Campbell, R. C.; Dugan, G. F.; Flanagan, J.; McArdle, K. E.; Miller, M. I.; Palmer, M. A.; Ramirez, G. A.; Sonnad, K. G.; Totten, M. M.; Tucker, S. L.; Williams, H. A.
2016-04-01
Electron cloud related emittance dilution and instabilities of bunch trains limit the performance of high intensity circular colliders. One of the key goals of the Cornell electron-positron storage ring Test Accelerator (CesrTA) research program is to improve our understanding of how the electron cloud alters the dynamics of bunches within the train. Single bunch beam diagnotics have been developed to measure the beam spectra, vertical beam size, two important dynamical effects of beams interacting with the electron cloud, for bunch trains on a turn-by-turn basis. Experiments have been performed at CesrTA to probe the interaction of the electron cloud with stored positron bunch trains. The purpose of these experiments was to characterize the dependence of beam-electron cloud interactions on the machine parameters such as bunch spacing, vertical chromaticity, and bunch current. The beam dynamics of the stored beam, in the presence of the electron cloud, was quantified using: 1) a gated beam position monitor (BPM) and spectrum analyzer to measure the bunch-by-bunch frequency spectrum of the bunch trains; 2) an x-ray beam size monitor to record the bunch-by-bunch, turn-by-turn vertical size of each bunch within the trains. In this paper we report on the observations from these experiments and analyze the effects of the electron cloud on the stability of bunches in a train under many different operational conditions.
Pan, Tao; Liu, Chunyan; Zeng, Xinying; Xin, Qiao; Xu, Meiying; Deng, Yangwu; Dong, Wei
2017-06-01
A recent work has shown that hydrophobic organic compounds solubilized in the micelle phase of some nonionic surfactants present substrate toxicity to microorganisms with increasing bioavailability. However, in cloud point systems, biotoxicity is prevented, because the compounds are solubilized into a coacervate phase, thereby leaving a fraction of compounds with cells in a dilute phase. This study extends the understanding of the relationship between substrate toxicity and bioavailability of hydrophobic organic compounds solubilized in nonionic surfactant micelle phase and cloud point system. Biotoxicity experiments were conducted with naphthalene and phenanthrene in the presence of mixed nonionic surfactants Brij30 and TMN-3, which formed a micelle phase or cloud point system at different concentrations. Saccharomyces cerevisiae, unable to degrade these compounds, was used for the biotoxicity experiments. Glucose in the cloud point system was consumed faster than in the nonionic surfactant micelle phase, indicating that the solubilized compounds had increased toxicity to cells in the nonionic surfactant micelle phase. The results were verified by subsequent biodegradation experiments. The compounds were degraded faster by PAH-degrading bacterium in the cloud point system than in the micelle phase. All these results showed that biotoxicity of the hydrophobic organic compounds increases with bioavailability in the surfactant micelle phase but remains at a low level in the cloud point system. These results provide a guideline for the application of cloud point systems as novel media for microbial transformation or biodegradation.
Cloud computing and validation of expandable in silico livers
2010-01-01
Background In Silico Livers (ISLs) are works in progress. They are used to challenge multilevel, multi-attribute, mechanistic hypotheses about the hepatic disposition of xenobiotics coupled with hepatic responses. To enhance ISL-to-liver mappings, we added discrete time metabolism, biliary elimination, and bolus dosing features to a previously validated ISL and initiated re-validated experiments that required scaling experiments to use more simulated lobules than previously, more than could be achieved using the local cluster technology. Rather than dramatically increasing the size of our local cluster we undertook the re-validation experiments using the Amazon EC2 cloud platform. So doing required demonstrating the efficacy of scaling a simulation to use more cluster nodes and assessing the scientific equivalence of local cluster validation experiments with those executed using the cloud platform. Results The local cluster technology was duplicated in the Amazon EC2 cloud platform. Synthetic modeling protocols were followed to identify a successful parameterization. Experiment sample sizes (number of simulated lobules) on both platforms were 49, 70, 84, and 152 (cloud only). Experimental indistinguishability was demonstrated for ISL outflow profiles of diltiazem using both platforms for experiments consisting of 84 or more samples. The process was analogous to demonstration of results equivalency from two different wet-labs. Conclusions The results provide additional evidence that disposition simulations using ISLs can cover the behavior space of liver experiments in distinct experimental contexts (there is in silico-to-wet-lab phenotype similarity). The scientific value of experimenting with multiscale biomedical models has been limited to research groups with access to computer clusters. The availability of cloud technology coupled with the evidence of scientific equivalency has lowered the barrier and will greatly facilitate model sharing as well as provide straightforward tools for scaling simulations to encompass greater detail with no extra investment in hardware. PMID:21129207
Results of the Thailand Warm-Cloud Hygroscopic Particle Seeding Experiment.
NASA Astrophysics Data System (ADS)
Silverman, Bernard A.; Sukarnjanaset, Wathana
2000-07-01
A randomized, warm-rain enhancement experiment was carried out during 1995-98 in the Bhumibol catchment area in northwestern Thailand. The experiment was conducted in accordance with a randomized, floating single-target design. The seeding targets were semi-isolated, warm convective clouds, contained within a well-defined experimental unit, that, upon qualification, were selected for seeding or not seeding with calcium chloride particles in a random manner. The seeding was done by dispensing the calcium chloride particles at an average rate of 21 kg km1 per seeding pass into the updrafts of growing warm convective clouds (about 1-2 km above cloud base) that have not yet developed or, at most, have just started to develop a precipitation radar echo. The experiment was carried out by the Bureau of Royal Rainmaking and Agricultural Aviation (BRRAA) of the Ministry of Agriculture and Cooperatives as part of its Applied Atmospheric Resources Research Program, Phase 2.During the 4 yr of the experiment, a total of 67 experimental units (34 seeded and 33 nonseeded units) were qualified in accordance with the experimental design. Volume-scan data from a 10-cm Doppler radar at 5-min intervals were used to track each experimental unit, from which various radar-estimated properties of the experimental units were obtained. The statistical evaluation of the experiment was based on a rerandomization analysis of the single ratio of seeded to unseeded experimental unit lifetime properties. In 1997, the BRRAA acquired two sophisticated King Air 350 cloud-physics aircraft, providing the opportunity to obtain physical measurements of the aerosol characteristics of the environment in which the warm clouds grow, of the hydrometeor characteristics of seeded and unseeded clouds, and of the calcium chloride seeding plume dimensions and particle size distribution-information directly related to the effectiveness of the seeding conceptual model that was not directly available up to then.The evaluation of the Thailand warm-rain enhancement experiment has provided statistically significant evidence and supporting physical evidence that the seeding of warm convective clouds with calcium chloride particles produced more rain than was produced by their unseeded counterparts. An exploratory analysis of the time evolution of the seeding effects resulted in a significant revision to the seeding conceptual model.
Cloud-based NEXRAD Data Processing and Analysis for Hydrologic Applications
NASA Astrophysics Data System (ADS)
Seo, B. C.; Demir, I.; Keem, M.; Goska, R.; Weber, J.; Krajewski, W. F.
2016-12-01
The real-time and full historical archive of NEXRAD Level II data, covering the entire United States from 1991 to present, recently became available on Amazon cloud S3. This provides a new opportunity to rebuild the Hydro-NEXRAD software system that enabled users to access vast amounts of NEXRAD radar data in support of a wide range of research. The system processes basic radar data (Level II) and delivers radar-rainfall products based on the user's custom selection of features such as space and time domain, river basin, rainfall product space and time resolution, and rainfall estimation algorithms. The cloud-based new system can eliminate prior challenges faced by Hydro-NEXRAD data acquisition and processing: (1) temporal and spatial limitation arising from the limited data storage; (2) archive (past) data ingestion and format conversion; and (3) separate data processing flow for the past and real-time Level II data. To enhance massive data processing and computational efficiency, the new system is implemented and tested for the Iowa domain. This pilot study begins by ingesting rainfall metadata and implementing Hydro-NEXRAD capabilities on the cloud using the new polarimetric features, as well as the existing algorithm modules and scripts. The authors address the reliability and feasibility of cloud computation and processing, followed by an assessment of response times from an interactive web-based system.
Ignition of Combustible Dust Clouds by Strong Capacitive Electric Sparks of Short Discharge Times
NASA Astrophysics Data System (ADS)
Eckhoff, Rolf K.
2017-10-01
It has been known for more than half a century that the discharge times of capacitive electric sparks can influence the minimum ignition energies of dust clouds substantially. Experiments by various workers have shown that net electric-spark energies for igniting explosive dust clouds in air were reduced by a factor of the order of 100 when spark discharge times were increased from a few μs to 0.1-1 ms. Experiments have also shown that the disturbance of the dust cloud by the shock/blast wave emitted by "short" spark discharges is a likely reason for this. The disturbance increases with increasing spark energy. In this paper a hitherto unpublished comprehensive study of this problem is presented. The work was performed about 50 years ago, using sparks of comparatively high energies (strong sparks). Lycopodium was used as test dust. The experiments were conducted in a brass vessel of 1 L volume. A transient dust cloud was generated in the vessel by a blast of compressed air. Synchronization of appearance of dust cloud and spark discharge was obtained by breaking the spark gap down by the dust cloud itself. This may in fact also be one possible synchronization mechanism in accidental industrial dust explosions initiated by electrostatic sparks. The experimental results for various spark energies were expressed as the probability of ignition, based on 100 replicate experiments, as a function of the nominal dust concentration. All probabilities obtained were 0%
DOT National Transportation Integrated Search
2012-03-01
"The current experiment was intended to examine the effect of sensory information on pilot reactions to system : failures within a UAS control station simulation. This research also investigated the level of automation used in : controlling the aircr...
Wang, Weiguo; Liu, Xiaohong; Xie, Shaocheng; ...
2009-07-23
Here, cloud properties have been simulated with a new double-moment microphysics scheme under the framework of the single-column version of NCAR Community Atmospheric Model version 3 (CAM3). For comparison, the same simulation was made with the standard single-moment microphysics scheme of CAM3. Results from both simulations compared favorably with observations during the Tropical Warm Pool–International Cloud Experiment by the U.S. Department of Energy Atmospheric Radiation Measurement Program in terms of the temporal variation and vertical distribution of cloud fraction and cloud condensate. Major differences between the two simulations are in the magnitude and distribution of ice water content within themore » mixed-phase cloud during the monsoon period, though the total frozen water (snow plus ice) contents are similar. The ice mass content in the mixed-phase cloud from the new scheme is larger than that from the standard scheme, and ice water content extends 2 km further downward, which is in better agreement with observations. The dependence of the frozen water mass fraction on temperature from the new scheme is also in better agreement with available observations. Outgoing longwave radiation (OLR) at the top of the atmosphere (TOA) from the simulation with the new scheme is, in general, larger than that with the standard scheme, while the surface downward longwave radiation is similar. Sensitivity tests suggest that different treatments of the ice crystal effective radius contribute significantly to the difference in the calculations of TOA OLR, in addition to cloud water path. Numerical experiments show that cloud properties in the new scheme can respond reasonably to changes in the concentration of aerosols and emphasize the importance of correctly simulating aerosol effects in climate models for aerosol-cloud interactions. Further evaluation, especially for ice cloud properties based on in-situ data, is needed.« less
NASA Technical Reports Server (NTRS)
Wang, J.; Biasca, R.; Liewer, P. C.
1996-01-01
Although the existence of the critical ionization velocity (CIV) is known from laboratory experiments, no agreement has been reached as to whether CIV exists in the natural space environment. In this paper we move towards more realistic models of CIV and present the first fully three-dimensional, electromagnetic particle-in-cell Monte-Carlo collision (PIC-MCC) simulations of typical space-based CIV experiments. In our model, the released neutral gas is taken to be a spherical cloud traveling across a magnetized ambient plasma. Simulations are performed for neutral clouds with various sizes and densities. The effects of the cloud parameters on ionization yield, wave energy growth, electron heating, momentum coupling, and the three-dimensional structure of the newly ionized plasma are discussed. The simulations suggest that the quantitative characteristics of momentum transfers among the ion beam, neutral cloud, and plasma waves is the key indicator of whether CIV can occur in space. The missing factors in space-based CIV experiments may be the conditions necessary for a continuous enhancement of the beam ion momentum. For a typical shaped charge release experiment, favorable CIV conditions may exist only in a very narrow, intermediate spatial region some distance from the release point due to the effects of the cloud density and size. When CIV does occur, the newly ionized plasma from the cloud forms a very complex structure due to the combined forces from the geomagnetic field, the motion induced emf, and the polarization. Hence the detection of CIV also critically depends on the sensor location.
Demerouti, Evangelia; Veldhuis, Wouter; Coombes, Claire; Hunter, Rob
2018-06-18
In this study among airline pilots, we aim to uncover the work characteristics (job demands and resources) and the outcomes (job crafting, happiness and simulator training performance) that are related to burnout for this occupational group. Using a large sample of airline pilots, we showed that 40% of the participating pilots experience high burnout. In line with Job Demands-Resources theory, job demands were detrimental for simulator training performance because they made pilots more exhausted and less able to craft their job, whereas job resources had a favourable effect because they reduced feelings of disengagement and increased job crafting. Moreover, burnout was negatively related to pilots' happiness with life. These findings highlight the importance of psychosocial factors and health for valuable outcomes for both pilots and airlines. Practitioner Summary: Using an online survey among the members of a European pilots' professional association, we examined the relationship between psychosocial factors (work characteristics, burnout) and outcomes (simulator training performance, happiness). Forty per cent of the participating pilots experience high burnout. Job demands were detrimental, whereas job resources were favourable for simulator training performance/happiness. Twitter text: 40% of airline pilots experience burnout and psychosocial work factors and burnout relate to performance at pilots' simulator training.
NASA Technical Reports Server (NTRS)
Luo, Yali; Xu, Kuan-Man; Morrison, Hugh; McFarquhar, Greg M.; Wang, Zhien; Zhang, Gong
2007-01-01
A cloud-resolving model (CRM) is used to simulate the multiple-layer mixed-phase stratiform (MPS) clouds that occurred during a three-and-a-half day subperiod of the Department of Energy-Atmospheric Radiation Measurement Program s Mixed-Phase Arctic Cloud Experiment (M-PACE). The CRM is implemented with an advanced two-moment microphysics scheme, a state-of-the-art radiative transfer scheme, and a complicated third-order turbulence closure. Concurrent meteorological, aerosol, and ice nucleus measurements are used to initialize the CRM. The CRM is prescribed by time-varying large-scale advective tendencies of temperature and moisture and surface turbulent fluxes of sensible and latent heat. The CRM reproduces the occurrences of the single- and double-layer MPS clouds as revealed by the M-PACE observations. However, the simulated first cloud layer is lower and the second cloud layer thicker compared to observations. The magnitude of the simulated liquid water path agrees with that observed, but its temporal variation is more pronounced than that observed. As in an earlier study of single-layer cloud, the CRM also captures the major characteristics in the vertical distributions and temporal variations of liquid water content (LWC), total ice water content (IWC), droplet number concentration and ice crystal number concentration (nis) as suggested by the aircraft observations. However, the simulated mean values differ significantly from the observed. The magnitude of nis is especially underestimated by one order of magnitude. Sensitivity experiments suggest that the lower cloud layer is closely related to the surface fluxes of sensible and latent heat; the upper cloud layer is probably initialized by the large-scale advective cooling/moistening and maintained through the strong longwave (LW) radiative cooling near the cloud top which enhances the dynamical circulation; artificially turning off all ice-phase microphysical processes results in an increase in LWP by a factor of 3 due to interactions between the excessive LW radiative cooling and extra cloud water; heating caused by phase change of hydrometeors could affect the LWC and cloud top height by partially canceling out the LW radiative cooling. It is further shown that the resolved dynamical circulation appears to contribute more greatly to the evolution of the MPS cloud layers than the parameterized subgrid-scale circulation.
Cloud cover determination in polar regions from satellite imagery
NASA Technical Reports Server (NTRS)
Barry, R. G.; Key, J. R.; Maslanik, J. A.
1988-01-01
The principal objectives of this project are: (1) to develop suitable validation data sets to evaluate the effectiveness of the International Satellite Cloud Climatology Project (ISCCP) operational algorithm for cloud retrieval in polar regions and to validate model simulations of polar cloud cover; (2) to identify limitations of current procedures for varying atmospheric surface conditions, and to explore potential means to remedy them using textural classifiers; and (3) to compare synoptic cloud data from a control run experiment of the GISS climate model II with typical observed synoptic cloud patterns.
NASA Astrophysics Data System (ADS)
Mhashilkar, Parag; Tiradani, Anthony; Holzman, Burt; Larson, Krista; Sfiligoi, Igor; Rynge, Mats
2014-06-01
Scientific communities have been in the forefront of adopting new technologies and methodologies in the computing. Scientific computing has influenced how science is done today, achieving breakthroughs that were impossible to achieve several decades ago. For the past decade several such communities in the Open Science Grid (OSG) and the European Grid Infrastructure (EGI) have been using GlideinWMS to run complex application workflows to effectively share computational resources over the grid. GlideinWMS is a pilot-based workload management system (WMS) that creates on demand, a dynamically sized overlay HTCondor batch system on grid resources. At present, the computational resources shared over the grid are just adequate to sustain the computing needs. We envision that the complexity of the science driven by "Big Data" will further push the need for computational resources. To fulfill their increasing demands and/or to run specialized workflows, some of the big communities like CMS are investigating the use of cloud computing as Infrastructure-As-A-Service (IAAS) with GlideinWMS as a potential alternative to fill the void. Similarly, communities with no previous access to computing resources can use GlideinWMS to setup up a batch system on the cloud infrastructure. To enable this, the architecture of GlideinWMS has been extended to enable support for interfacing GlideinWMS with different Scientific and commercial cloud providers like HLT, FutureGrid, FermiCloud and Amazon EC2. In this paper, we describe a solution for cloud bursting with GlideinWMS. The paper describes the approach, architectural changes and lessons learned while enabling support for cloud infrastructures in GlideinWMS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mhashilkar, Parag; Tiradani, Anthony; Holzman, Burt
Scientific communities have been in the forefront of adopting new technologies and methodologies in the computing. Scientific computing has influenced how science is done today, achieving breakthroughs that were impossible to achieve several decades ago. For the past decade several such communities in the Open Science Grid (OSG) and the European Grid Infrastructure (EGI) have been using GlideinWMS to run complex application workflows to effectively share computational resources over the grid. GlideinWMS is a pilot-based workload management system (WMS) that creates on demand, a dynamically sized overlay HTCondor batch system on grid resources. At present, the computational resources shared overmore » the grid are just adequate to sustain the computing needs. We envision that the complexity of the science driven by 'Big Data' will further push the need for computational resources. To fulfill their increasing demands and/or to run specialized workflows, some of the big communities like CMS are investigating the use of cloud computing as Infrastructure-As-A-Service (IAAS) with GlideinWMS as a potential alternative to fill the void. Similarly, communities with no previous access to computing resources can use GlideinWMS to setup up a batch system on the cloud infrastructure. To enable this, the architecture of GlideinWMS has been extended to enable support for interfacing GlideinWMS with different Scientific and commercial cloud providers like HLT, FutureGrid, FermiCloud and Amazon EC2. In this paper, we describe a solution for cloud bursting with GlideinWMS. The paper describes the approach, architectural changes and lessons learned while enabling support for cloud infrastructures in GlideinWMS.« less
Daniel M. Johnson; William K. Smith
2008-01-01
The high altitude spruce-fir (Abies fraseri (Pursh) Poiret.-Picea rubens Sarg.) forests of the southern Appalachian Mountains, USA, experience frequent cloud immersion. Recent studies indicate that cloud bases may have risen over the past 30 years, resulting in less frequent forest cloud immersion, and that further increases in...
Physics Parameterization for Seasonal Prediction
2012-09-30
comparison Project, a joint effort between the Year of Tropical Convection (YOTC) Program and the Global Energy and Water Cycle Experiment (GEWEX) Cloud...unified” representation of the water cycle in the model. One such area is the correspondence between diagnosed cloud cover and prognostic cloud
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feng, Zhe; McFarlane, Sally A.; Schumacher, Courtney
2014-05-16
To improve understanding of the convective processes key to the Madden-Julian-Oscillation (MJO) initiation, the Dynamics of the MJO (DYNAMO) and Atmospheric Radiation Measurement MJO Investigation Experiment (AMIE) collected four months of observations from three radars, the S-band Polarization Radar (S-Pol), the C-band Shared Mobile Atmospheric Research & Teaching Radar (SMART-R), and Ka-band Zenith Radar (KAZR) on Addu Atoll in the tropical Indian Ocean. This study compares the measurements from the S-Pol and SMART-R to those from the more sensitive KAZR in order to characterize the hydrometeor detection capabilities of the two scanning precipitation radars. Frequency comparisons for precipitating convective cloudsmore » and non-precipitating high clouds agree much better than non-precipitating low clouds for both scanning radars due to issues in ground clutter. On average, SMART-R underestimates convective and high cloud tops by 0.3 to 1.1 km, while S-Pol underestimates cloud tops by less than 0.4 km for these cloud types. S-Pol shows excellent dynamic range in detecting various types of clouds and therefore its data are well suited for characterizing the evolution of the 3D cloud structures, complementing the profiling KAZR measurements. For detecting non-precipitating low clouds and thin cirrus clouds, KAZR remains the most reliable instrument. However, KAZR is attenuated in heavy precipitation and underestimates cloud top height due to rainfall attenuation 4.3% of the time during DYNAMO/AMIE. An empirical method to correct the KAZR cloud top heights is described, and a merged radar dataset is produced to provide improved cloud boundary estimates, microphysics and radiative heating retrievals.« less
Gyroplane accidents 1985-2005: epidemiological analysis and pilot factors in 223 events.
Pagán, Brian J; de Voogt, Alex
2008-10-01
Gyroplanes (autogyros) are regarded as a relatively safe and stable type of general-aviation aircraft. The U.S. Federal Aviation Administration categorizes them as sport pilot/light sport aircraft, and reports of gyroplane accidents are included in a publicly available database. We hypothesized that issues related to pilot experience and aircraft maintenance would affect the severity of accidents as indicated by aircraft damage and fatalities. A search of the National Transportation Safety Board database for the period 1985-2005 yielded 223 reports of gyroplane accidents. Information from those reports was compiled and cross-referenced with pilot performance breakdowns and contextual information. The data was then analyzed using the Human Factors Analysis and Classification System. There was a strong effect of pilot experience on crash outcomes; compared to more experienced pilots, crashes involving pilots with less than 40 flight hours in the same make/model gyroplane were five times more likely to involve loss of control, twice as likely to destroy the aircraft, and four times more likely to involve fatalities. On the other hand, crashes involving pilots with more than 40 make/model hours were more likely to be related to perception-based performance breakdown. Maintenance issues were not found to play a significant role in this sample of crashes. The results support the hypothesis that pilot experience is a significant predictor of accident fatality in gyroplanes. Training that is adapted to the experience level of pilots as implemented in new FAA regulations for sport pilot and light sport aircraft (2004) may help to reduce the frequency and seriousness of gyroplane accidents.
GEWEX Cloud Systems Study (GCSS)
NASA Technical Reports Server (NTRS)
Moncrieff, Mitch
1993-01-01
The Global Energy and Water Cycle Experiment (GEWEX) Cloud Systems Study (GCSS) program seeks to improve the physical understanding of sub-grid scale cloud processes and their representation in parameterization schemes. By improving the description and understanding of key cloud system processes, GCSS aims to develop the necessary parameterizations in climate and numerical weather prediction (NWP) models. GCSS will address these issues mainly through the development and use of cloud-resolving or cumulus ensemble models to generate realizations of a set of archetypal cloud systems. The focus of GCSS is on mesoscale cloud systems, including precipitating convectively-driven cloud systems like MCS's and boundary layer clouds, rather than individual clouds, and on their large-scale effects. Some of the key scientific issues confronting GCSS that particularly relate to research activities in the central U.S. are presented.
Fine-scale Horizontal Structure of Arctic Mixed-Phase Clouds.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rambukkange,M.; Verlinde, J.; Elorante, E.
2006-07-10
Recent in situ observations in stratiform clouds suggest that mixed phase regimes, here defined as limited cloud volumes containing both liquid and solid water, are constrained to narrow layers (order 100 m) separating all-liquid and fully glaciated volumes (Hallett and Viddaurre, 2005). The Department of Energy Atmospheric Radiation Measurement Program's (DOE-ARM, Ackerman and Stokes, 2003) North Slope of Alaska (NSA) ARM Climate Research Facility (ACRF) recently started collecting routine measurement of radar Doppler velocity power spectra from the Millimeter Cloud Radar (MMCR). Shupe et al. (2004) showed that Doppler spectra has potential to separate the contributions to the total reflectivitymore » of the liquid and solid water in the radar volume, and thus to investigate further Hallett and Viddaurre's findings. The Mixed-Phase Arctic Cloud Experiment (MPACE) was conducted along the NSA to investigate the properties of Arctic mixed phase clouds (Verlinde et al., 2006). We present surface based remote sensing data from MPACE to discuss the fine-scale structure of the mixed-phase clouds observed during this experiment.« less
1997-05-24
The Space Shuttle orbiter Atlantis rolls out on Runway 33 of KSC’s Shuttle Landing Facility at the conclusion of the nine-day STS-84 mission. The Shuttle Training Aircraft piloted by astronaut Kenneth D. Cockrell, acting deputy chief of the Astronaut Office, is flying above Atlantis. The Vehicle Assembly Building is at left. Main gear touchdown was at 9:27:44 EDT on May 24, 1997. The first landing opportunity was waved off because of low cloud cover. It was the 37th landing at KSC since the Shuttle program began in 1981, and the eighth consecutive landing at KSC. STS-84 was the sixth of nine planned dockings of the Space Shuttle with the Russian Space Station Mir. Atlantis was docked with the Mir for five days. STS-84 Mission Specialist C. Michael Foale replaced astronaut and Mir 23 crew member Jerry M. Linenger, who has been on the Russian space station since Jan. 15. Linenger returned to Earth on Atlantis with the rest of the STS-84 crew, Mission Commander Charles J. Precourt, Pilot Eileen Marie Collins, and Mission Specialists Carlos I. Noriega, Edward Tsang Lu, Elena V. Kondakova of the Russian Space Agency and JeanFrancois Clervoy of the European Space Agency. Foale is scheduled to remain on the Mir for approximately four months, until he is replaced by STS-86 crew member Wendy B. Lawrence in September. Besides the docking and crew exchange, STS-84 included the transfer of more than 7,300 pounds of water, logistics and science experiments and hardware to and from the Mir. Scientific experiments conducted during the STS-84 mission, and scheduled for Foale’s stay on the Mir, are in the fields of advanced technology, Earth sciences, fundamental biology, human life sciences, International Space Station risk mitigation, microgravity sciences and space sciences
1997-05-24
The Space Shuttle orbiter Atlantis, with its drag chute deployed, rolls out on Runway 33 of KSC’s Shuttle Landing Facility at the conclusion of the nine-day STS-84 mission. The Shuttle Training Aircraft piloted by astronaut Kenneth D. Cockrell, acting deputy chief of the Astronaut Office, is flying above Atlantis. Main gear touchdown was at 9:27:44 EDT on May 24, 1997. The first landing opportunity was waved off because of low cloud cover. It was the 37th landing at KSC since the Shuttle program began in 1981, and the eighth consecutive landing at KSC. STS-84 was the sixth of nine planned dockings of the Space Shuttle with the Russian Space Station Mir. Atlantis was docked with the Mir for five days. STS-84 Mission Specialist C. Michael Foale replaced astronaut and Mir 23 crew member Jerry M. Linenger, who has been on the Russian space station since Jan. 15. Linenger returned to Earth on Atlantis with the rest of the STS-84 crew, Mission Commander Charles J. Precourt, Pilot Eileen Marie Collins, and Mission Specialists Carlos I. Noriega, Edward Tsang Lu, Elena V. Kondakova of the Russian Space Agency and JeanFrancois Clervoy of the European Space Agency. Foale is scheduled to remain on the Mir for approximately four months, until he is replaced by STS-86 crew member Wendy B. Lawrence in September. Besides the docking and crew exchange, STS-84 included the transfer of more than 7,300 pounds of water, logistics and science experiments and hardware to and from the Mir. Scientific experiments conducted during the STS-84 mission, and scheduled for Foale’s stay on the Mir, are in the fields of advanced technology, Earth sciences, fundamental biology, human life sciences, International Space Station risk mitigation, microgravity sciences and space sciences
14 CFR 61.160 - Aeronautical experience-airplane category restricted privileges.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aeronautical experience-airplane category... INSTRUCTORS Airline Transport Pilots § 61.160 Aeronautical experience—airplane category restricted privileges... pilot may apply for an airline transport pilot certificate with an airplane category multiengine class...
NASA Astrophysics Data System (ADS)
Ogura, Tomoo; Shiogama, Hideo; Watanabe, Masahiro; Yoshimori, Masakazu; Yokohata, Tokuta; Annan, James D.; Hargreaves, Julia C.; Ushigami, Naoto; Hirota, Kazuya; Someya, Yu; Kamae, Youichi; Tatebe, Hiroaki; Kimoto, Masahide
2017-12-01
This study discusses how much of the biases in top-of-atmosphere (TOA) radiation and clouds can be removed by parameter tuning in the present-day simulation of a climate model in the Coupled Model Inter-comparison Project phase 5 (CMIP5) generation. We used output of a perturbed parameter ensemble (PPE) experiment conducted with an atmosphere-ocean general circulation model (AOGCM) without flux adjustment. The Model for Interdisciplinary Research on Climate version 5 (MIROC5) was used for the PPE experiment. Output of the PPE was compared with satellite observation data to evaluate the model biases and the parametric uncertainty of the biases with respect to TOA radiation and clouds. The results indicate that removing or changing the sign of the biases by parameter tuning alone is difficult. In particular, the cooling bias of the shortwave cloud radiative effect at low latitudes could not be removed, neither in the zonal mean nor at each latitude-longitude grid point. The bias was related to the overestimation of both cloud amount and cloud optical thickness, which could not be removed by the parameter tuning either. However, they could be alleviated by tuning parameters such as the maximum cumulus updraft velocity at the cloud base. On the other hand, the bias of the shortwave cloud radiative effect in the Arctic was sensitive to parameter tuning. It could be removed by tuning such parameters as albedo of ice and snow both in the zonal mean and at each grid point. The obtained results illustrate the benefit of PPE experiments which provide useful information regarding effectiveness and limitations of parameter tuning. Implementing a shallow convection parameterization is suggested as a potential measure to alleviate the biases in radiation and clouds.
NASA Technical Reports Server (NTRS)
Whitlock, Charles H.; Cox, Stephen K.; Lecroy, Stuart R.
1990-01-01
Tables are presented which show data from five sites in the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE)/Surface Radiation Budget (SRB) Wisconsin experiment regional from October 12 through November 2, 1986. A discussion of intercomparison results is also included. The field experiment was conducted for the purposes of both intensive cirrus-cloud measurements and SRB algorithm validation activities.
Interactions among Radiation, Convection, and Large-Scale Dynamics in a General Circulation Model.
NASA Astrophysics Data System (ADS)
Randall, David A.; Harshvardhan; Dazlich, Donald A.; Corsetti, Thomas G.
1989-07-01
We have analyzed the effects of radiatively active clouds on the climate simulated by the UCLA/GLA GCM, with particular attention to the effects of the upper tropospheric stratiform clouds associated with deep cumulus convection, and the interactions of these clouds with convection and the large-scale circulation.Several numerical experiments have been performed to investigate the mechanisms through which the clouds influence the large-scale circulation. In the `NODETLQ' experiment, no liquid water or ice was detrained from cumulus clouds into the environment; all of the condensate was rained out. Upper level supersaturation cloudiness was drastically reduced, the atmosphere dried, and tropical outgoing longwave radiation increased. In the `NOANVIL' experiment, the radiative effects of the optically thich upper-level cloud sheets associated with deep cumulus convection were neglected. The land surface received more solar radiation in regions of convection, leading to enhanced surface fluxes and a dramatic increase in precipitation. In the `NOCRF' experiment, the longwave atmospheric cloud radiative forcing (ACRF) was omitted, paralleling the recent experiment of Slingo and Slingo. The results suggest that the ACRF enhances deep penetrative convection and precipitation, while suppressing shallow convection. They also indicate that the ACRF warms and moistens the tropical troposphere. The results of this experiment are somewhat ambiguous, however; for example, the ACRF suppresses precipitation in some parts of the tropics, and enhances it in others.To isolate the effects of the ACRF in a simpler setting, we have analyzed the climate of an ocean-covered Earth, which we call Seaworld. The key simplicities of Seaworld are the fixed boundary temperature with no land points, the lack of mountains, and the zonal uniformity of the boundary conditions. Results are presented from two Seaworld simulations. The first includes a full suite of physical parameterizations, while the second omits all radiative effects of the clouds. The differences between the two runs are, therefore, entirely due to the direct and indirect and indirect effects of the ACRF. Results show that the ACRF in the cloudy run accurately represents the radiative heating perturbation relative to the cloud-free run. The cloudy run is warmer in the middle troposphere, contains much more precipitable water, and has about 15% more globally averaged precipitation. There is a double tropical rain band in the cloud-free run, and a single, more intense tropical rain band in the cloudy run. The cloud-free run produces relatively weak but frequent cumulus convection, while the cloudy run produces relatively intense but infrequent convection. The mean meridional circulation transport nearly twice as much mass in the cloudy run. The increased tropical rising motion in the cloudy run leads to a deeper boundary layer and also to more moisture in the troposphere above the boundary layer. This accounts for the increased precipitable water content of the atmosphere. The clouds lead to an increase in the intensity of the tropical easterlies, and cause the midlatitude westerly jets to shift equatorward.Taken together, our results show that upper tropospheric clouds associated with moist convection, whose importance has recently been emphasized in observational studies, play a very complex and powerful role in determining the model results. This points to a need to develop more realistic parameterizations of these clouds.
Statistical properties of a cloud ensemble - A numerical study
NASA Technical Reports Server (NTRS)
Tao, Wei-Kuo; Simpson, Joanne; Soong, Su-Tzai
1987-01-01
The statistical properties of cloud ensembles under a specified large-scale environment, such as mass flux by cloud drafts and vertical velocity as well as the condensation and evaporation associated with these cloud drafts, are examined using a three-dimensional numerical cloud ensemble model described by Soong and Ogura (1980) and Tao and Soong (1986). The cloud drafts are classified as active and inactive, and separate contributions to cloud statistics in areas of different cloud activity are then evaluated. The model results compare well with results obtained from aircraft measurements of a well-organized ITCZ rainband that occurred on August 12, 1974, during the Global Atmospheric Research Program's Atlantic Tropical Experiment.
NASA Astrophysics Data System (ADS)
Sun, Lin; Liu, Xinyan; Yang, Yikun; Chen, TingTing; Wang, Quan; Zhou, Xueying
2018-04-01
Although enhanced over prior Landsat instruments, Landsat 8 OLI can obtain very high cloud detection precisions, but for the detection of cloud shadows, it still faces great challenges. Geometry-based cloud shadow detection methods are considered the most effective and are being improved constantly. The Function of Mask (Fmask) cloud shadow detection method is one of the most representative geometry-based methods that has been used for cloud shadow detection with Landsat 8 OLI. However, the Fmask method estimates cloud height employing fixed temperature rates, which are highly uncertain, and errors of large area cloud shadow detection can be caused by errors in estimations of cloud height. This article improves the geometry-based cloud shadow detection method for Landsat OLI from the following two aspects. (1) Cloud height no longer depends on the brightness temperature of the thermal infrared band but uses a possible dynamic range from 200 m to 12,000 m. In this case, cloud shadow is not a specific location but a possible range. Further analysis was carried out in the possible range based on the spectrum to determine cloud shadow location. This effectively avoids the cloud shadow leakage caused by the error in the height determination of a cloud. (2) Object-based and pixel spectral analyses are combined to detect cloud shadows, which can realize cloud shadow detection from two aspects of target scale and pixel scale. Based on the analysis of the spectral differences between the cloud shadow and typical ground objects, the best cloud shadow detection bands of Landsat 8 OLI were determined. The combined use of spectrum and shape can effectively improve the detection precision of cloud shadows produced by thin clouds. Several cloud shadow detection experiments were carried out, and the results were verified by the results of artificial recognition. The results of these experiments indicated that this method can identify cloud shadows in different regions with correct accuracy exceeding 80%, approximately 5% of the areas were wrongly identified, and approximately 10% of the cloud shadow areas were missing. The accuracy of this method is obviously higher than the recognition accuracy of Fmask, which has correct accuracy lower than 60%, and the missing recognition is approximately 40%.
NASA Astrophysics Data System (ADS)
Barabanova, Olga
2013-04-01
Nowadays the Main Aviation Meteorological Centre in Moscow (MAMC) provides forecasts of icing conditions in Moscow Region airports using information of surface observation network, weather radars and atmospheric sounding. Unfortunately, satellite information is not used properly in aviation meteorological offices in Moscow Region: weather forecasters deal with satellites images of cloudiness only. The main forecasters of MAMC realise that it is necessary to employ meteorological satellite numerical data from different channels in aviation forecasting and especially in nowcasting. Algorithm of nowcasting aircraft in-flight icing conditions has been developed using data from geostationary meteorological satellites "Meteosat-7" and "Meteosat-9". The algorithm is based on the brightness temperature differences. Calculation of brightness temperature differences help to discriminate clouds with supercooled large drops where severe icing conditions are most likely. Due to the lack of visible channel data, the satellite icing detection methods will be less accurate at night. Besides this method is limited by optically thick ice clouds where it is not possible to determine the extent to which supercooled large drops exists within the underlying clouds. However, we determined that most of the optically thick cases are associated with convection or mid-latitude cyclones and they will nearly always have a layer where which supercooled large drops exists with an icing threat. This product is created hourly for the Moscow Air Space and mark zones with moderate or severe icing hazards. The results were compared with mesoscale numerical atmospheric model COSMO-RU output. Verification of the algorithms results using aircraft pilot reports shows that this algorithm is a good instrument for the operational practise in aviation meteorological offices in Moscow Region. The satellite-based algorithms presented here can be used in real time to diagnose areas of icing for pilots to avoid.
NASA Technical Reports Server (NTRS)
Kooi, Susan; Fenn, Marta; Ismail, Syed; Ferrare, Richard; Hair, John; Browell, Edward; Notari, Anthony; Butler, Carolyn; Burton, Sharon; Simpson, Steven
2008-01-01
Large scale distributions of ozone, water vapor, aerosols, and clouds were measured throughout the troposphere by two NASA Langley lidar systems on board the NASA DC-8 aircraft as part of the Tropical Composition, Cloud, and Climate Coupling Experiment (TC4) over Central and South America and adjacent oceans in the summer of 2007. Special emphasis was placed on the sampling of convective outflow and transport, sub-visible cirrus clouds, boundary layer aerosols, Saharan dust, volcanic emissions, and urban and biomass burning plumes. This paper presents preliminary results from this campaign, and demonstrates the value of coordinated measurements by the two lidar systems.
NASA Astrophysics Data System (ADS)
Hoose, C.; Hande, L. B.; Mohler, O.; Niemand, M.; Paukert, M.; Reichardt, I.; Ullrich, R.
2016-12-01
Between 0 and -37°C, ice formation in clouds is triggered by aerosol particles acting as heterogeneous ice nuclei. At lower temperatures, heterogeneous ice nucleation on aerosols can occur at lower supersaturations than homogeneous freezing of solutes. In laboratory experiments, the ability of different aerosol species (e.g. desert dusts, soot, biological particles) has been studied in detail and quantified via various theoretical or empirical parameterization approaches. For experiments in the AIDA cloud chamber, we have quantified the ice nucleation efficiency via a temperature- and supersaturation dependent ice nucleation active site density. Here we present a new empirical parameterization scheme for immersion and deposition ice nucleation on desert dust and soot based on these experimental data. The application of this parameterization to the simulation of cirrus clouds, deep convective clouds and orographic clouds will be shown, including the extension of the scheme to the treatment of freezing of rain drops. The results are compared to other heterogeneous ice nucleation schemes. Furthermore, an aerosol-dependent parameterization of contact ice nucleation is presented.
Teaching Cybersecurity Using the Cloud
ERIC Educational Resources Information Center
Salah, Khaled; Hammoud, Mohammad; Zeadally, Sherali
2015-01-01
Cloud computing platforms can be highly attractive to conduct course assignments and empower students with valuable and indispensable hands-on experience. In particular, the cloud can offer teaching staff and students (whether local or remote) on-demand, elastic, dedicated, isolated, (virtually) unlimited, and easily configurable virtual machines.…
Liquid Water Cloud Properties During the Polarimeter Definition Experiment (PODEX)
NASA Technical Reports Server (NTRS)
Alexandrov, Mikhail D.; Cairns, Brian; Wasilewski, Andrzei P.; Ackerman, Andrew S.; McGill, Matthew J.; Yorks, John E.; Hlavka, Dennis L.; Platnick, Steven; Arnold, George; Van Diedenhoven, Bastiaan;
2015-01-01
We present retrievals of water cloud properties from the measurements made by the Research Scanning Polarimeter (RSP) during the Polarimeter Definition Experiment (PODEX) held between January 14 and February 6, 2013. The RSP was onboard the high-altitude NASA ER-2 aircraft based at NASA Dryden Aircraft Operation Facility in Palmdale, California. The retrieved cloud characteristics include cloud optical thickness, effective radius and variance of cloud droplet size distribution derived using a parameter-fitting technique, as well as the complete droplet size distribution function obtained by means of Rainbow Fourier Transform. Multi-modal size distributions are decomposed into several modes and the respective effective radii and variances are computed. The methodology used to produce the retrieval dataset is illustrated on the examples of a marine stratocumulus deck off California coast and stratus/fog over California's Central Valley. In the latter case the observed bimodal droplet size distributions were attributed to two-layer cloud structure. All retrieval data are available online from NASA GISS website.
Campaign datasets for ARM Cloud Aerosol Precipitation Experiment (ACAPEX)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leung, L. Ruby; Mei, Fan; Comstock, Jennifer
This campaign consisted of the deployment of the DOE ARM Mobile Facility 2 (AMF2) and the ARM Aerial Facility (AAF) G-1 in a field campaign called ARM Cloud Aerosol Precipitation Experiment (ACAPEX), which took place in conjunction with CalWater 2- a NOAA field campaign. The joint CalWater 2/ACAPEX field campaign aimed to improve understanding and modeling of large-scale dynamics and cloud and precipitation processes associated with ARs and aerosol-cloud interactions that influence precipitation variability and extremes in the western U.S. The observational strategy consisted of the use of land and offshore assets to monitor: 1. the evolution and structure ofmore » ARs from near their regions of development 2. the long-range transport of aerosols in the eastern North Pacific and potential interactions with ARs 3. how aerosols from long-range transport and local sources influence cloud and precipitation in the U.S. West Coast where ARs make landfall and post-frontal clouds are frequent.« less
Making the most of cloud storage - a toolkit for exploitation by WLCG experiments
NASA Astrophysics Data System (ADS)
Alvarez Ayllon, Alejandro; Arsuaga Rios, Maria; Bitzes, Georgios; Furano, Fabrizio; Keeble, Oliver; Manzi, Andrea
2017-10-01
Understanding how cloud storage can be effectively used, either standalone or in support of its associated compute, is now an important consideration for WLCG. We report on a suite of extensions to familiar tools targeted at enabling the integration of cloud object stores into traditional grid infrastructures and workflows. Notable updates include support for a number of object store flavours in FTS3, Davix and gfal2, including mitigations for lack of vector reads; the extension of Dynafed to operate as a bridge between grid and cloud domains; protocol translation in FTS3; the implementation of extensions to DPM (also implemented by the dCache project) to allow 3rd party transfers over HTTP. The result is a toolkit which facilitates data movement and access between grid and cloud infrastructures, broadening the range of workflows suitable for cloud. We report on deployment scenarios and prototype experience, explaining how, for example, an Amazon S3 or Azure allocation can be exploited by grid workflows.
Observational and Modeling Studies of Clouds and the Hydrological Cycle
NASA Technical Reports Server (NTRS)
Somerville, Richard C. J.
1997-01-01
Our approach involved validating parameterizations directly against measurements from field programs, and using this validation to tune existing parameterizations and to guide the development of new ones. We have used a single-column model (SCM) to make the link between observations and parameterizations of clouds, including explicit cloud microphysics (e.g., prognostic cloud liquid water used to determine cloud radiative properties). Surface and satellite radiation measurements were used to provide an initial evaluation of the performance of the different parameterizations. The results of this evaluation will then used to develop improved cloud and cloud-radiation schemes, which were tested in GCM experiments.
Kaleri works with the Pilot experiment during Expedition 8
2003-10-31
ISS008-E-05179 (31 October 2003) --- Cosmonaut Alexander Y. Kaleri, Expedition 8 flight engineer, works with the Russian biomedical Pilot experiment (MBI-15) in the Zvezda Service Module on the International Space Station (ISS). The experiment, which looks at psychological and physiological changes in crew performance during long-duration spaceflight, requires a worktable, ankle restraint system and two control handles for testing piloting skill. Kaleri represents Rosaviakosmos.
Chen, Ying-Hsien; Hung, Chi-Sheng; Huang, Ching-Chang; Hung, Yu-Chien
2017-01-01
Background Atrial fibrillation (AF) is a common form of arrhythmia that is associated with increased risk of stroke and mortality. Detecting AF before the first complication occurs is a recognized priority. No previous studies have examined the feasibility of undertaking AF screening using a telehealth surveillance system with an embedded cloud-computing algorithm; we address this issue in this study. Objective The objective of this study was to evaluate the feasibility of AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm. Methods We conducted a prospective AF screening study in a nonmetropolitan area using a single-lead electrocardiogram (ECG) recorder. All ECG measurements were reviewed on the telehealth surveillance system and interpreted by the cloud-computing algorithm and a cardiologist. The process of AF screening was evaluated with a satisfaction questionnaire. Results Between March 11, 2016 and August 31, 2016, 967 ECGs were recorded from 922 residents in nonmetropolitan areas. A total of 22 (2.4%, 22/922) residents with AF were identified by the physician’s ECG interpretation, and only 0.2% (2/967) of ECGs contained significant artifacts. The novel cloud-computing algorithm for AF detection had a sensitivity of 95.5% (95% CI 77.2%-99.9%) and specificity of 97.7% (95% CI 96.5%-98.5%). The overall satisfaction score for the process of AF screening was 92.1%. Conclusions AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm is feasible. PMID:28951384
NASA Technical Reports Server (NTRS)
Johnson, Daniel E.; Tao, W.-K.; Simpson, J.; Sui, C.-H.; Einaudi, Franco (Technical Monitor)
2001-01-01
Interactions between deep tropical clouds over the western Pacific warm pool and the larger-scale environment are key to understanding climate change. Cloud models are an extremely useful tool in simulating and providing statistical information on heat and moisture transfer processes between cloud systems and the environment, and can therefore be utilized to substantially improve cloud parameterizations in climate models. In this paper, the Goddard Cumulus Ensemble (GCE) cloud-resolving model is used in multi-day simulations of deep tropical convective activity over the Tropical Ocean-Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE). Large-scale temperature and moisture advective tendencies, and horizontal momentum from the TOGA-COARE Intensive Flux Array (IFA) region, are applied to the GCE version which incorporates cyclical boundary conditions. Sensitivity experiments show that grid domain size produces the largest response to domain-mean temperature and moisture deviations, as well as cloudiness, when compared to grid horizontal or vertical resolution, and advection scheme. It is found that a minimum grid-domain size of 500 km is needed to adequately resolve the convective cloud features. The control experiment shows that the atmospheric heating and moistening is primarily a response to cloud latent processes of condensation/evaporation, and deposition/sublimation, and to a lesser extent, melting of ice particles. Air-sea exchange of heat and moisture is found to be significant, but of secondary importance, while the radiational response is small. The simulated rainfall and atmospheric heating and moistening, agrees well with observations, and performs favorably to other models simulating this case.
Flight simulator platform motion and air transport pilot training
NASA Technical Reports Server (NTRS)
Lee, Alfred T.; Bussolari, Steven R.
1987-01-01
The effect of a flight simulator platform motion on the performance and training of a pilot was evaluated using subjective ratings and objective performance data obtained on experienced B-727 pilots and pilots with no prior heavy aircraft flying experience flying B-727-200 aircraft simulator used by the FAA in the upgrade and transition training for air carrier operations. The results on experienced pilots did not reveal any reliable effects of wide variations in platform motion design. On the other hand, motion variations significantly affected the behavior of pilots without heavy-aircraft experience. The effect was limited to pitch attitude control inputs during the early phase of landing training.
The Cloud Detection and Ultraviolet Monitoring Experiment (CLUE)
NASA Technical Reports Server (NTRS)
Barbier, Louis M.; Loh, Eugene C.; Krizmanic, John F.; Sokolsky, Pierre; Streitmatter, Robert E.
2004-01-01
In this paper we describe a new balloon instrument - CLUE - which is designed to monitor ultraviolet (uv) nightglow levels and determine cloud cover and cloud heights with a CO2 slicing technique. The CO2 slicing technique is based on the MODIS instrument on NASA's Aqua and Terra spacecraft. CLUE will provide higher spatial resolution (0.5 km) and correlations between the uv and the cloud cover.
Cloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals
Shupe, Matthew
2013-05-22
Time-height fields of retrieved in-cloud vertical wind velocity and turbulent dissipation rate, both retrieved primarily from vertically-pointing, Ka-band cloud radar measurements. Files are available for manually-selected, stratiform, mixed-phase cloud cases observed at the North Slope of Alaska (NSA) site during periods covering the Mixed-Phase Arctic Cloud Experiment (MPACE, late September through early November 2004) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC, April-early May 2008). These time periods will be expanded in a future submission.
Security-aware Virtual Machine Allocation in the Cloud: A Game Theoretic Approach
2015-01-13
predecessor, however, this paper used empirical evidence and actual data from running experiments on the Amazon EC2 cloud . They began by running all 5...is through effective VM allocation management of the cloud provider to ensure delivery of maximum security for all cloud users. The negative... Cloud : A Game Theoretic Approach 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f
Managing virtual machines with Vac and Vcycle
NASA Astrophysics Data System (ADS)
McNab, A.; Love, P.; MacMahon, E.
2015-12-01
We compare the Vac and Vcycle virtual machine lifecycle managers and our experiences in providing production job execution services for ATLAS, CMS, LHCb, and the GridPP VO at sites in the UK, France and at CERN. In both the Vac and Vcycle systems, the virtual machines are created outside of the experiment's job submission and pilot framework. In the case of Vac, a daemon runs on each physical host which manages a pool of virtual machines on that host, and a peer-to-peer UDP protocol is used to achieve the desired target shares between experiments across the site. In the case of Vcycle, a daemon manages a pool of virtual machines on an Infrastructure-as-a-Service cloud system such as OpenStack, and has within itself enough information to create the types of virtual machines to achieve the desired target shares. Both systems allow unused shares for one experiment to temporarily taken up by other experiements with work to be done. The virtual machine lifecycle is managed with a minimum of information, gathered from the virtual machine creation mechanism (such as libvirt or OpenStack) and using the proposed Machine/Job Features API from WLCG. We demonstrate that the same virtual machine designs can be used to run production jobs on Vac and Vcycle/OpenStack sites for ATLAS, CMS, LHCb, and GridPP, and that these technologies allow sites to be operated in a reliable and robust way.
Design of an off-axis visual display based on a free-form projection screen to realize stereo vision
NASA Astrophysics Data System (ADS)
Zhao, Yuanming; Cui, Qingfeng; Piao, Mingxu; Zhao, Lidong
2017-10-01
A free-form projection screen is designed for an off-axis visual display, which shows great potential in applications such as flight training for providing both accommodation and convergence cues for pilots. The method based on point cloud is proposed for the design of the free-form surface, and the design of the point cloud is controlled by a program written in the macro-language. In the visual display based on the free-form projection screen, when the error of the screen along Z-axis is 1 mm, the error of visual distance at each filed is less than 1%. And the resolution of the design for full field is better than 1‧, which meet the requirement of resolution for human eyes.
Measurement of the line-of-sight velocity of high-altitude barium clouds A technique
NASA Technical Reports Server (NTRS)
Mende, S. B.; Harris, S. E.
1982-01-01
It is demonstrated that for maximizing the scientific output of future ionospheric and magnetospheric ion cloud release experiments a new type of instrument is required which will measure the line-of-sight velocity of the ion cloud by the Doppler technique. A simple instrument was constructed using a 5-cm diam solid Fabry-Perot etalon coupled to a low-light-level integrating TV camera. It was demonstrated that the system has both the sensitivity and spectral resolution for detection of ion clouds and measurement of their line-of-sight Doppler velocity. The tests consisted of (1) a field experiment using a rocket barium cloud release to check sensitivity, and (2) laboratory experiments to show the spectral resolving capabilities of the system. The instrument was found to be operational if the source was brighter than approximately 1 kR, and it had a wavelength resolution much better than 0.2 A, which corresponds to approximately 12 km/sec or in the case of barium ion an acceleration potential of 100 V. The instrument is rugged and, therefore, simple to use in field experiments or on flight instruments. The sensitivity limit of the instrument can be increased by increasing the size of the etalon.
Thermodynamic and cloud parameter retrieval using infrared spectral data
NASA Technical Reports Server (NTRS)
Zhou, Daniel K.; Smith, William L., Sr.; Liu, Xu; Larar, Allen M.; Huang, Hung-Lung A.; Li, Jun; McGill, Matthew J.; Mango, Stephen A.
2005-01-01
High-resolution infrared radiance spectra obtained from near nadir observations provide atmospheric, surface, and cloud property information. A fast radiative transfer model, including cloud effects, is used for atmospheric profile and cloud parameter retrieval. The retrieval algorithm is presented along with its application to recent field experiment data from the NPOESS Airborne Sounding Testbed - Interferometer (NAST-I). The retrieval accuracy dependence on cloud properties is discussed. It is shown that relatively accurate temperature and moisture retrievals can be achieved below optically thin clouds. For optically thick clouds, accurate temperature and moisture profiles down to cloud top level are obtained. For both optically thin and thick cloud situations, the cloud top height can be retrieved with an accuracy of approximately 1.0 km. Preliminary NAST-I retrieval results from the recent Atlantic-THORPEX Regional Campaign (ATReC) are presented and compared with coincident observations obtained from dropsondes and the nadir-pointing Cloud Physics Lidar (CPL).
NASA Technical Reports Server (NTRS)
Smith, William L., Jr.; Minnis, Patrick; Alvarez, Joseph M.; Uttal, Taneil; Intrieri, Janet M.; Ackerman, Thomas P.; Clothiaux, Eugene
1993-01-01
Cloud-top height is a major factor determining the outgoing longwave flux at the top of the atmosphere. The downwelling radiation from the cloud strongly affects the cooling rate within the atmosphere and the longwave radiation incident at the surface. Thus, determination of cloud-base temperature is important for proper calculation of fluxes below the cloud. Cloud-base altitude is also an important factor in aircraft operations. Cloud-top height or temperature can be derived in a straightforward manner using satellite-based infrared data. Cloud-base temperature, however, is not observable from the satellite, but is related to the height, phase, and optical depth of the cloud in addition to other variables. This study uses surface and satellite data taken during the First ISCCP Regional Experiment (FIRE) Phase-2 Intensive Field Observation (IFO) period (13 Nov. - 7 Dec. 1991, to improve techniques for deriving cloud-base height from conventional satellite data.
The effect of clouds on the earth's radiation budget
NASA Technical Reports Server (NTRS)
Ziskin, Daniel; Strobel, Darrell F.
1991-01-01
The radiative fluxes from the Earth Radiation Budget Experiment (ERBE) and the cloud properties from the International Satellite Cloud Climatology Project (ISCCP) over Indonesia for the months of June and July of 1985 and 1986 were analyzed to determine the cloud sensitivity coefficients. The method involved a linear least squares regression between co-incident flux and cloud coverage measurements. The calculated slope is identified as the cloud sensitivity. It was found that the correlations between the total cloud fraction and radiation parameters were modest. However, correlations between cloud fraction and IR flux were improved by separating clouds by height. Likewise, correlations between the visible flux and cloud fractions were improved by distinguishing clouds based on optical depth. Calculating correlations between the net fluxes and either height or optical depth segregated cloud fractions were somewhat improved. When clouds were classified in terms of their height and optical depth, correlations among all the radiation components were improved. Mean cloud sensitivities based on the regression of radiative fluxes against height and optical depth separated cloud types are presented. Results are compared to a one-dimensional radiation model with a simple cloud parameterization scheme.
Cloud Radiation Forcings and Feedbacks: General Circulation Model Tests and Observational Validation
NASA Technical Reports Server (NTRS)
Lee,Wan-Ho; Iacobellis, Sam F.; Somerville, Richard C. J.
1997-01-01
Using an atmospheric general circulation model (the National Center for Atmospheric Research Community Climate Model: CCM2), the effects on climate sensitivity of several different cloud radiation parameterizations have been investigated. In addition to the original cloud radiation scheme of CCM2, four parameterizations incorporating prognostic cloud water were tested: one version with prescribed cloud radiative properties and three other versions with interactive cloud radiative properties. The authors' numerical experiments employ perpetual July integrations driven by globally constant sea surface temperature forcings of two degrees, both positive and negative. A diagnostic radiation calculation has been applied to investigate the partial contributions of high, middle, and low cloud to the total cloud radiative forcing, as well as the contributions of water vapor, temperature, and cloud to the net climate feedback. The high cloud net radiative forcing is positive, and the middle and low cloud net radiative forcings are negative. The total net cloud forcing is negative in all of the model versions. The effect of interactive cloud radiative properties on global climate sensitivity is significant. The net cloud radiative feedbacks consist of quite different shortwave and longwave components between the schemes with interactive cloud radiative properties and the schemes with specified properties. The increase in cloud water content in the warmer climate leads to optically thicker middle- and low-level clouds and in turn to negative shortwave feedbacks for the interactive radiative schemes, while the decrease in cloud amount simply produces a positive shortwave feedback for the schemes with a specified cloud water path. For the longwave feedbacks, the decrease in high effective cloudiness for the schemes without interactive radiative properties leads to a negative feedback, while for the other cases, the longwave feedback is positive. These cloud radiation parameterizations are empirically validated by using a single-column diagnostic model. together with measurements from the Atmospheric Radiation Measurement program and from the Tropical Ocean Global Atmosphere Combined Ocean-Atmosphere Response Experiment. The inclusion of prognostic cloud water produces a notable improvement in the realism of the parameterizations, as judged by these observations. Furthermore, the observational evidence suggests that deriving cloud radiative properties from cloud water content and microphysical characteristics is a promising route to further improvement.
Experience of the JPL Exploratory Data Analysis Team at validating HIRS2/MSU cloud parameters
NASA Technical Reports Server (NTRS)
Kahn, Ralph; Haskins, Robert D.; Granger-Gallegos, Stephanie; Pursch, Andrew; Delgenio, Anthony
1992-01-01
Validation of the HIRS2/MSU cloud parameters began with the cloud/climate feedback problem. The derived effective cloud amount is less sensitive to surface temperature for higher clouds. This occurs because as the cloud elevation increases, the difference between surface temperature and cloud temperature increases, so only a small change in cloud amount is needed to effect a large change in radiance at the detector. By validating the cloud parameters it is meant 'developing a quantitative sense for the physical meaning of the measured parameters', by: (1) identifying the assumptions involved in deriving parameters from the measured radiances, (2) testing the input data and derived parameters for statistical error, sensitivity, and internal consistency, and (3) comparing with similar parameters obtained from other sources using other techniques.
The Transition from Diffuse to Dense Gas in Herschel Dust Emission Maps
NASA Astrophysics Data System (ADS)
Goldsmith, Paul
Dense cores in dark clouds are the sites where young stars form. These regions manifest as relatively small (<0.1pc) pockets of cold and dense gas. If we wish to understand the star formation process, we have to understand the physical conditions in dense cores. This has been a main aim of star formation research in the past decade. Today, we do indeed possess a good knowledge of the density and velocity structure of cores, as well as their chemical evolution and physical lifetime. However, we do not understand well how dense cores form out of the diffuse gas clouds surrounding them. It is crucial that we constrain the relationship between dense cores and their environment: if we only understand dense cores, we may be able to understand how individual stars form --- but we would not know how the star forming dense cores themselves come into existence. We therefore propose to obtain data sets that reveal both dense cores and the clouds containing them in the same map. Based on these maps, we will study how dense cores form out of their natal clouds. Since cores form stars, this knowledge is crucial for the development of a complete theoretical and observational understanding of the formation of stars and their planets, as envisioned in NASA's Strategic Science Plan. Fortunately, existing archival data allow to derive exactly the sort of maps we need for our analysis. Here, we describe a program that exclusively builds on PACS and SPIRE dust emission imaging data from the NASA-supported Herschel mission. The degree-sized wide-field Herschel maps of the nearby (<260pc) Polaris Flare and Aquila Rift clouds are ideal for our work. They permit to resolve dense cores (<0.1pc), while the maps also reveal large-scale cloud structure (5pc and larger). We will generate column density maps from these dust emission maps and then run a tree-based hierarchical multi-scale structure analysis on them. Only this procedure permits to exploit the full potential of the maps: we will characterize cloud structure over a vast range of spatial scales. This work has many advantages over previous studies, where information about dense cores and their environment was pieced together using a variety of methods an instruments. Now, the Herschel maps permit for the first time to characterize both molecular clouds and their cores in one shot in a single data set. We use these data to answer a variety of simple yet very important questions. First, we study whether dense cores have sharp boundaries. If such boundaries exist, they would indicate that dense cores have an individual identity well-separate from the near-fractal cloud structure on larger spatial scales. Second, we will --- in very approximate sense --- derive global density gradients for molecular clouds from radii <0.1pc to 5pc and larger. These "synoptic" density gradients provide a useful quantitative description of the relation between cloud material at very different spatial scales. Also, these measurements can be compared to synoptic density gradients derived in the same fashion for theoretical cloud models. Third, we study how dense cores are nested into the "clumps" forming molecular clouds, i.e., we study whether the most massive dense cores in a cloud (<0.1pc) reside in the most massive regions identified on lager spatial scale (1pc and larger). This will show how the properties of dense cores are influenced by their environment. Our study will derive unique constraints to cloud structure. But our small sample forbids to make strong statements. This pilot study does thus prepare future larger efforts. Our entire project builds on data reduction and analysis methods which our team has used in the past. This guarantees a swift completion of the project with predictable efficiency. We present pilot studies that demonstrate that the data and analysis methods are suited to tackle the science goals. This project is thus guaranteed to return significant results.
Ring structure of a neutral gas cloud studied in a one-dimensional expansion into space
NASA Technical Reports Server (NTRS)
Davidson, R. E.
1972-01-01
A one dimensional treatment of the expansion of a gas cloud of uncharged particles into vacuum is discussed. It is determined that the whole cloud does not change from continuum to free molecular flow at the same time. Some regions of the cloud make the transition sooner than others. An explanation of the ring structure observed during barium cloud experiments is presented using this conclusion. An analysis of the velocity distributions for the two kinds of flow yields a velocity distribution for the whole cloud that exhibits ring structure.
STS-64 and 747-SCA Ferry Flight Takeoff
1994-09-26
The Space Shuttle Discovery, mated to NASA's 747 Shuttle Carrier Aircraft (SCA), takes to the air for its ferry flight back to the Kennedy Space Center in Florida. The spacecraft, with a crew of six, was launched into a 57-degree high inclination orbit from the Kennedy Space Center, Florida, at 3:23 p.m., 9 September 1994. The mission featured the study of clouds and the atmosphere with a laser beaming system called Lidar In-Space Technology Experiment (LITE), and the first untethered space walk in ten years. A Spartan satellite was also deployed and later retrieved in the study of the sun's corona and solar wind. The mission was scheduled to end Sunday, 18 September, but was extended one day to continue science work. Bad weather at the Kennedy Space Center on 19 September, forced a one-day delay to September 20, with a weather divert that day to Edwards. Mission commander was Richard Richards, the pilot Blaine Hammond, while mission specialists were Jerry Linenger, Susan Helms, Carl Meade, and Mark Lee.
1994-09-20
The Space Shuttle Discovery settles to the main runway at Edwards, California, at 2:13 p.m. (PDT) 20 September 1994, to conclude mission STS-64. The spacecraft, with a crew of six, was launched into a 57-degree high inclination orbit from the Kennedy Space Center, Florida, at 3:23 p.m. (PDT), 9 September 1994. The mission featured the study of clouds and the atmosphere with a laser beaming system called Lidar In-Space Technology Experiment (LITE), and the first untethered space walk in over ten years. A Spartan satellite was also deployed and later retrieved in the study of the sun's corona and the solar wind. The mission was scheduled to end Sunday, 18 September, but was extended one day to continue science work. Bad weather at the Kennedy Space Center on September 19, forced a one-day delay to September 20, with a weather divert that day to Edwards. Mission commander was Richard Richards, the pilot Blaine Hammond, while mission specialists were Jerry Linenger, Susan Helms, Carl Meade, and Mark Lee.
Space Shuttle Discovery lifts off successfully
NASA Technical Reports Server (NTRS)
1998-01-01
Clouds of exhaust and blazing light fill Launch Pad 39B as Space Shuttle Discovery lifts off at 2:19 p.m. EST Oct. 29 on mission STS-95. Making his second voyage into space after 36 years is Payload Specialist John H. Glenn Jr., senator from Ohio. Other crew members are Mission Commander Curtis L. Brown Jr., Pilot Steven W. Lindsey, Payload Specialist Chiaki Mukai, (M.D., Ph.D.), with the National Space Development Agency of Japan (NASDA), Mission Specialist Stephen K. Robinson, Mission Specialist Pedro Duque of Spain, representing the European Space Agency (ESA), and Mission Specialist Scott E. Parazynski. The STS-95 mission includes research payloads such as the Spartan solar-observing deployable spacecraft, the Hubble Space Telescope Orbital Systems Test Platform, the International Extreme Ultraviolet Hitchhiker, as well as the SPACEHAB single module with experiments on space flight and the aging process. Discovery is expected to return to KSC at 11:49 a.m. EST on Nov. 7.
Space Shuttle Discovery lifts off successfully
NASA Technical Reports Server (NTRS)
1998-01-01
Clouds of exhaust seem to fill the marsh near Launch Pad 39B as Space Shuttle Discovery lifts off at 2:19 p.m. EST Oct. 29 on mission STS-95. Making his second voyage into space after 36 years is Payload Specialist John H. Glenn Jr., senator from Ohio. Other crew members are Mission Commander Curtis L. Brown Jr., Pilot Steven W. Lindsey, Payload Specialist Chiaki Mukai, (M.D., Ph.D.), with the National Space Development Agency of Japan (NASDA), Mission Specialist Stephen K. Robinson, Mission Specialist Pedro Duque of Spain, representing the European Space Agency (ESA), and Mission Specialist Scott E. Parazynski. The STS-95 mission includes research payloads such as the Spartan solar-observing deployable spacecraft, the Hubble Space Telescope Orbital Systems Test Platform, the International Extreme Ultraviolet Hitchhiker, as well as the SPACEHAB single module with experiments on space flight and the aging process. Discovery is expected to return to KSC at 11:49 a.m. EST on Nov. 7.
Foale works with the Pilot experiment during Expedition 8
2003-10-31
ISS008-E-05181 (31 October 2003) --- Astronaut C. Michael Foale, Expedition 8 mission commander and NASA ISS science officer, works with the Russian biomedical Pilot experiment (MBI-15) in the Zvezda Service Module on the International Space Station (ISS). The experiment, which looks at psychological and physiological changes in crew performance during long-duration spaceflight, requires a worktable, ankle restraint system and two control handles for testing piloting skill.
Meteorological support to the West German-United States Barium Ion Cloud Project.
NASA Technical Reports Server (NTRS)
Westfall, R. R.; Chamberlain, L. W.
1972-01-01
The objective of the Barium Ion Cloud Project was to study a barium ionized cloud released at an altitude of 5 earth radii. Accurate forecasting of weather conditions to prevail during the experiment period was critical to the project success. Good seeing conditions were required at all optical sites during the experiment. All meteorological support was the responsibility of the National Weather Service at Wallops Station, Virginia. Preliminary results confirm the scientists' theories of the magnetic fields and the existence of electric fields in the magnetosphere.
NASA Astrophysics Data System (ADS)
Stagni, F.; McNab, A.; Luzzi, C.; Krzemien, W.; Consortium, DIRAC
2017-10-01
In the last few years, new types of computing models, such as IAAS (Infrastructure as a Service) and IAAC (Infrastructure as a Client), gained popularity. New resources may come as part of pledged resources, while others are in the form of opportunistic ones. Most but not all of these new infrastructures are based on virtualization techniques. In addition, some of them, present opportunities for multi-processor computing slots to the users. Virtual Organizations are therefore facing heterogeneity of the available resources and the use of an Interware software like DIRAC to provide the transparent, uniform interface has become essential. The transparent access to the underlying resources is realized by implementing the pilot model. DIRAC’s newest generation of generic pilots (the so-called Pilots 2.0) are the “pilots for all the skies”, and have been successfully released in production more than a year ago. They use a plugin mechanism that makes them easily adaptable. Pilots 2.0 have been used for fetching and running jobs on every type of resource, being it a Worker Node (WN) behind a CREAM/ARC/HTCondor/DIRAC Computing element, a Virtual Machine running on IaaC infrastructures like Vac or BOINC, on IaaS cloud resources managed by Vcycle, the LHCb High Level Trigger farm nodes, and any type of opportunistic computing resource. Make a machine a “Pilot Machine”, and all diversities between them will disappear. This contribution describes how pilots are made suitable for different resources, and the recent steps taken towards a fully unified framework, including monitoring. Also, the cases of multi-processor computing slots either on real or virtual machines, with the whole node or a partition of it, is discussed.
Weather Fundamentals: Clouds. [Videotape].
ERIC Educational Resources Information Center
1998
The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) discusses how clouds form, the different types of clouds, and the important role they play in…
Using Clouds for MapReduce Measurement Assignments
ERIC Educational Resources Information Center
Rabkin, Ariel; Reiss, Charles; Katz, Randy; Patterson, David
2013-01-01
We describe our experiences teaching MapReduce in a large undergraduate lecture course using public cloud services and the standard Hadoop API. Using the standard API, students directly experienced the quality of industrial big-data tools. Using the cloud, every student could carry out scalability benchmarking assignments on realistic hardware,…
Trust-Enhanced Cloud Service Selection Model Based on QoS Analysis.
Pan, Yuchen; Ding, Shuai; Fan, Wenjuan; Li, Jing; Yang, Shanlin
2015-01-01
Cloud computing technology plays a very important role in many areas, such as in the construction and development of the smart city. Meanwhile, numerous cloud services appear on the cloud-based platform. Therefore how to how to select trustworthy cloud services remains a significant problem in such platforms, and extensively investigated owing to the ever-growing needs of users. However, trust relationship in social network has not been taken into account in existing methods of cloud service selection and recommendation. In this paper, we propose a cloud service selection model based on the trust-enhanced similarity. Firstly, the direct, indirect, and hybrid trust degrees are measured based on the interaction frequencies among users. Secondly, we estimate the overall similarity by combining the experience usability measured based on Jaccard's Coefficient and the numerical distance computed by Pearson Correlation Coefficient. Then through using the trust degree to modify the basic similarity, we obtain a trust-enhanced similarity. Finally, we utilize the trust-enhanced similarity to find similar trusted neighbors and predict the missing QoS values as the basis of cloud service selection and recommendation. The experimental results show that our approach is able to obtain optimal results via adjusting parameters and exhibits high effectiveness. The cloud services ranking by our model also have better QoS properties than other methods in the comparison experiments.
Trust-Enhanced Cloud Service Selection Model Based on QoS Analysis
Pan, Yuchen; Ding, Shuai; Fan, Wenjuan; Li, Jing; Yang, Shanlin
2015-01-01
Cloud computing technology plays a very important role in many areas, such as in the construction and development of the smart city. Meanwhile, numerous cloud services appear on the cloud-based platform. Therefore how to how to select trustworthy cloud services remains a significant problem in such platforms, and extensively investigated owing to the ever-growing needs of users. However, trust relationship in social network has not been taken into account in existing methods of cloud service selection and recommendation. In this paper, we propose a cloud service selection model based on the trust-enhanced similarity. Firstly, the direct, indirect, and hybrid trust degrees are measured based on the interaction frequencies among users. Secondly, we estimate the overall similarity by combining the experience usability measured based on Jaccard’s Coefficient and the numerical distance computed by Pearson Correlation Coefficient. Then through using the trust degree to modify the basic similarity, we obtain a trust-enhanced similarity. Finally, we utilize the trust-enhanced similarity to find similar trusted neighbors and predict the missing QoS values as the basis of cloud service selection and recommendation. The experimental results show that our approach is able to obtain optimal results via adjusting parameters and exhibits high effectiveness. The cloud services ranking by our model also have better QoS properties than other methods in the comparison experiments. PMID:26606388
Evaluating Cloud Initialization in a Convection-permit NWP Model
NASA Astrophysics Data System (ADS)
Li, Jia; Chen, Baode
2015-04-01
In general, to avoid "double counting precipitation" problem, in convection permit NWP models, it was a common practice to turn off convective parameterization. However, if there were not any cloud information in the initial conditions, the occurrence of precipitation could be delayed due to spin-up of cloud field or microphysical variables. In this study, we utilized the complex cloud analysis package from the Advanced Regional Prediction System (ARPS) to adjust the initial states of the model on water substance, such as cloud water, cloud ice, rain water, et al., that is, to initialize the microphysical variables (i.e., hydrometers), mainly based on radar reflectivity observations. Using the Advanced Research WRF (ARW) model, numerical experiments with/without cloud initialization and convective parameterization were carried out at grey-zone resolutions (i.e. 1, 3, and 9 km). The results from the experiments without convective parameterization indicate that model ignition with radar reflectivity can significantly reduce spin-up time and accurately simulate precipitation at the initial time. In addition, it helps to improve location and intensity of predicted precipitation. With grey-zone resolutions (i.e. 1, 3, and 9 km), using the cumulus convective parameterization scheme (without radar data) cannot produce realistic precipitation at the early time. The issues related to microphysical parametrization associated with cloud initialization were also discussed.
Viper NHEXS Program: A Viper Pilot Neck Health & Conditioning Guide
2012-11-01
recommended in this manual. The Neck vs. Gs Problem At least one acute neck pain episode is reported to occur in an estimated 85% of all pilots flying...high-performance fighter type aircraft, with the yearly prevalence of neck-related pain for all pilots at 56% [1]. Vandebeek reported over 50% of...72% of fighter pilots experience neck pain in relation to flying, while 35% experience some low back pain . The reported average G level for acute
Clouds and the Earth's Radiant Energy System (CERES)
NASA Technical Reports Server (NTRS)
Carman, Stephen L.; Cooper, John E.; Miller, James; Harrison, Edwin F.; Barkstrom, Bruce R.
1992-01-01
The CERES (Clouds and the Earth's Radiant Energy System) experiment will play a major role in NASA's multi-platform Earth Observing System (EOS) program to observe and study the global climate. The CERES instruments will provide EOS scientists with a consistent data base of accurately known fields of radiation and of clouds. CERES will investigate the important question of cloud forcing and its influence on the radiative energy flow through the Earth's atmosphere. The CERES instrument is an improved version of the ERBE (Earth Radiation Budget Experiment) broadband scanning radiometer flown by NASA from 1984 through 1989. This paper describes the science of CERES, presents an overview of the instrument preliminary design, and outlines the issues related to spacecraft pointing and attitude control.
NASA Astrophysics Data System (ADS)
Nichman, Leonid; Järvinen, Emma; Dorsey, James; Connolly, Paul; Duplissy, Jonathan; Fuchs, Claudia; Ignatius, Karoliina; Sengupta, Kamalika; Stratmann, Frank; Möhler, Ottmar; Schnaiter, Martin; Gallagher, Martin
2017-09-01
Optical probes are frequently used for the detection of microphysical cloud particle properties such as liquid and ice phase, size and morphology. These properties can eventually influence the angular light scattering properties of cirrus clouds as well as the growth and accretion mechanisms of single cloud particles. In this study we compare four commonly used optical probes to examine their response to small cloud particles of different phase and asphericity. Cloud simulation experiments were conducted at the Cosmics Leaving OUtdoor Droplets (CLOUD) chamber at European Organisation for Nuclear Research (CERN). The chamber was operated in a series of multi-step adiabatic expansions to produce growth and sublimation of ice particles at super- and subsaturated ice conditions and for initial temperatures of -30, -40 and -50 °C. The experiments were performed for ice cloud formation via homogeneous ice nucleation. We report the optical observations of small ice particles in deep convection and in situ cirrus simulations. Ice crystal asphericity deduced from measurements of spatially resolved single particle light scattering patterns by the Particle Phase Discriminator mark 2 (PPD-2K, Karlsruhe edition) were compared with Cloud and Aerosol Spectrometer with Polarisation (CASPOL) measurements and image roundness captured by the 3View Cloud Particle Imager (3V-CPI). Averaged path light scattering properties of the simulated ice clouds were measured using the Scattering Intensity Measurements for the Optical detectioN of icE (SIMONE) and single particle scattering properties were measured by the CASPOL. We show the ambiguity of several optical measurements in ice fraction determination of homogeneously frozen ice in the case where sublimating quasi-spherical ice particles are present. Moreover, most of the instruments have difficulties of producing reliable ice fraction if small aspherical ice particles are present, and all of the instruments cannot separate perfectly spherical ice particles from supercooled droplets. Correlation analysis of bulk averaged path depolarisation measurements and single particle measurements of these clouds showed higher R2 values at high concentrations and small diameters, but these results require further confirmation. We find that none of these instruments were able to determine unambiguously the phase of the small particles. These results have implications for the interpretation of atmospheric measurements and parametrisations for modelling, particularly for low particle number concentration clouds.
Gateau, Thibault; Ayaz, Hasan; Dehais, Frédéric
2018-01-01
There is growing interest for implementing tools to monitor cognitive performance in naturalistic work and everyday life settings. The emerging field of research, known as neuroergonomics, promotes the use of wearable and portable brain monitoring sensors such as functional near infrared spectroscopy (fNIRS) to investigate cortical activity in a variety of human tasks out of the laboratory. The objective of this study was to implement an on-line passive fNIRS-based brain computer interface to discriminate two levels of working memory load during highly ecological aircraft piloting tasks. Twenty eight recruited pilots were equally split into two groups (flight simulator vs. real aircraft). In both cases, identical approaches and experimental stimuli were used (serial memorization task, consisting in repeating series of pre-recorded air traffic control instructions, easy vs. hard). The results show pilots in the real flight condition committed more errors and had higher anterior prefrontal cortex activation than pilots in the simulator, when completing cognitively demanding tasks. Nevertheless, evaluation of single trial working memory load classification showed high accuracy (>76%) across both experimental conditions. The contributions here are two-fold. First, we demonstrate the feasibility of passively monitoring cognitive load in a realistic and complex situation (live piloting of an aircraft). In addition, the differences in performance and brain activity between the two experimental conditions underscore the need for ecologically-valid investigations. PMID:29867411
Gateau, Thibault; Ayaz, Hasan; Dehais, Frédéric
2018-01-01
There is growing interest for implementing tools to monitor cognitive performance in naturalistic work and everyday life settings. The emerging field of research, known as neuroergonomics, promotes the use of wearable and portable brain monitoring sensors such as functional near infrared spectroscopy (fNIRS) to investigate cortical activity in a variety of human tasks out of the laboratory. The objective of this study was to implement an on-line passive fNIRS-based brain computer interface to discriminate two levels of working memory load during highly ecological aircraft piloting tasks. Twenty eight recruited pilots were equally split into two groups (flight simulator vs. real aircraft). In both cases, identical approaches and experimental stimuli were used (serial memorization task, consisting in repeating series of pre-recorded air traffic control instructions, easy vs. hard). The results show pilots in the real flight condition committed more errors and had higher anterior prefrontal cortex activation than pilots in the simulator, when completing cognitively demanding tasks. Nevertheless, evaluation of single trial working memory load classification showed high accuracy (>76%) across both experimental conditions. The contributions here are two-fold. First, we demonstrate the feasibility of passively monitoring cognitive load in a realistic and complex situation (live piloting of an aircraft). In addition, the differences in performance and brain activity between the two experimental conditions underscore the need for ecologically-valid investigations.
The EOS CERES Global Cloud Mask
NASA Technical Reports Server (NTRS)
Berendes, T. A.; Welch, R. M.; Trepte, Q.; Schaaf, C.; Baum, B. A.
1996-01-01
To detect long-term climate trends, it is essential to produce long-term and consistent data sets from a variety of different satellite platforms. With current global cloud climatology data sets, such as the International Satellite Cloud Climatology Experiment (ISCCP) or CLAVR (Clouds from Advanced Very High Resolution Radiometer), one of the first processing steps is to determine whether an imager pixel is obstructed between the satellite and the surface, i.e., determine a cloud 'mask.' A cloud mask is essential to studies monitoring changes over ocean, land, or snow-covered surfaces. As part of the Earth Observing System (EOS) program, a series of platforms will be flown beginning in 1997 with the Tropical Rainfall Measurement Mission (TRMM) and subsequently the EOS-AM and EOS-PM platforms in following years. The cloud imager on TRMM is the Visible/Infrared Sensor (VIRS), while the Moderate Resolution Imaging Spectroradiometer (MODIS) is the imager on the EOS platforms. To be useful for long term studies, a cloud masking algorithm should produce consistent results between existing (AVHRR) data, and future VIRS and MODIS data. The present work outlines both existing and proposed approaches to detecting cloud using multispectral narrowband radiance data. Clouds generally are characterized by higher albedos and lower temperatures than the underlying surface. However, there are numerous conditions when this characterization is inappropriate, most notably over snow and ice of the cloud types, cirrus, stratocumulus and cumulus are the most difficult to detect. Other problems arise when analyzing data from sun-glint areas over oceans or lakes over deserts or over regions containing numerous fires and smoke. The cloud mask effort builds upon operational experience of several groups that will now be discussed.
Laboratory simulations of cumulus cloud flows explain the entrainment anomaly
NASA Astrophysics Data System (ADS)
Narasimha, Roddam; Diwan, Sourabh S.; Subrahmanyam, Duvvuri; Sreenivas, K. R.; Bhat, G. S.
2010-11-01
In the present laboratory experiments, cumulus cloud flows are simulated by starting plumes and jets subjected to off-source heat addition in amounts that are dynamically similar to latent heat release due to condensation in real clouds. The setup permits incorporation of features like atmospheric inversion layers and the active control of off-source heat addition. Herein we report, for the first time, simulation of five different cumulus cloud types (and many shapes), including three genera and three species (WMO Atlas 1987), which show striking resemblance to real clouds. It is known that the rate of entrainment in cumulus cloud flows is much less than that in classical plumes - the main reason for the failure of early entrainment models. Some of the previous studies on steady-state jets and plumes (done in a similar setup) have attributed this anomaly to the disruption of the large-scale turbulent structures upon the addition of off-source heat. We present estimates of entrainment coefficients from these measurements which show a qualitatively consistent variation with height. We propose that this explains the observed entrainment anomaly in cumulus clouds; further experiments are planned to address this question in the context of starting jets and plumes.
NASA Technical Reports Server (NTRS)
Minnis, Patrick; Young, David F.; Heck, Patrick W.; Liou, Kuo-Nan; Takano, Yoshihide
1992-01-01
The First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE) Phase II Intensive Field Observations (IFO) were taken over southeastern Kansas between November 13 and December 7,1991, to determine cirrus cloud properties. The observations include in situ microphysical data; surface, aircraft, and satellite remote sensing; and measurements of divergence over meso- and smaller-scale areas using wind profilers. Satellite remote sensing of cloud characteristics is an essential aspect for understanding and predicting the role of clouds in climate variations. The objectives of the satellite cloud analysis during FIRE are to validate cloud property retrievals, develop advanced methods for extracting cloud information from satellite-measured radiances, and provide multiscale cloud data for cloud process studies and for verification of cloud generation models. This paper presents the initial results of cloud property analyses during FIRE-II using Geostationary Operational Environmental Satellite (GOES) data and NOAA Advanced Very High Resolution Radiometer (AVHRR) radiances.
Trust Model to Enhance Security and Interoperability of Cloud Environment
NASA Astrophysics Data System (ADS)
Li, Wenjuan; Ping, Lingdi
Trust is one of the most important means to improve security and enable interoperability of current heterogeneous independent cloud platforms. This paper first analyzed several trust models used in large and distributed environment and then introduced a novel cloud trust model to solve security issues in cross-clouds environment in which cloud customer can choose different providers' services and resources in heterogeneous domains can cooperate. The model is domain-based. It divides one cloud provider's resource nodes into the same domain and sets trust agent. It distinguishes two different roles cloud customer and cloud server and designs different strategies for them. In our model, trust recommendation is treated as one type of cloud services just like computation or storage. The model achieves both identity authentication and behavior authentication. The results of emulation experiments show that the proposed model can efficiently and safely construct trust relationship in cross-clouds environment.
NASA Astrophysics Data System (ADS)
Boudala, Faisal; Wu, Di; Gultepe, Ismail; Anderson, Martha; turcotte, marie-france
2017-04-01
In-flight aircraft icing is one of the major weather hazards to aviation . It occurs when an aircraft passes through a cloud layer containing supercooled drops (SD). The SD in contact with the airframe freezes on the surface which degrades the performance of the aircraft.. Prediction of in-flight icing requires accurate prediction of SD sizes, liquid water content (LWC), and temperature. The current numerical weather predicting (NWP) models are not capable of making accurate prediction of SD sizes and associated LWC. Aircraft icing environment is normally studied by flying research aircraft, which is quite expensive. Thus, developing a ground based remote sensing system for detection of supercooled liquid clouds and characterization of their impact on severity of aircraft icing one of the important tasks for improving the NWPs based predictions and validations. In this respect, Environment and Climate Change Canada (ECCC) in cooperation with the Department of National Defense (DND) installed a number of specialized ground based remote sensing platforms and present weather sensors at Cold Lake, Alberta that includes a multi-channel microwave radiometer (MWR), K-band Micro Rain radar (MRR), Ceilometer, Parsivel distrometer and Vaisala PWD22 present weather sensor. In this study, a number of pilot reports confirming icing events and freezing precipitation that occurred at Cold Lake during the 2014-2016 winter periods and associated observation data for the same period are examined. The icing events are also examined using aircraft icing intensity estimated using ice accumulation model which is based on a cylindrical shape approximation of airfoil and the Canadian High Resolution Regional Deterministic Prediction System (HRDPS) model predicted LWC, median volume diameter and temperature. The results related to vertical atmospheric profiling conditions, surface observations, and the Canadian High Resolution Regional Deterministic Prediction System (HRDPS) model predictions are given. Preliminary results suggest that remote sensing and present weather sensors based observations of cloud SD regions can be used to describe micro and macro physical characteristics of the icing conditions. The model based icing intensity prediction reasonably agreed with the PIREPs and MWR observations.
NASA Astrophysics Data System (ADS)
Schneider, D. J.
2009-12-01
The successful mitigation of volcanic hazards to aviation requires rapid interpretation and coordination of data from multiple sources, and communication of information products to a variety of end users. This community of information providers and information users include volcano observatories, volcanic ash advisory centers, meteorological watch offices, air traffic control centers, airline dispatch and military flight operations centers, and pilots. Each of these entities has capabilities and needs that are unique to their situations that evolve over a range of time spans. Prior to an eruption, information about probable eruption scenarios are needed in order to allow for contingency planning. Once a hazardous eruption begins, the immediate questions are where, when, how high, and how long will the eruption last? Following the initial detection of an eruption, the need for information changes to forecasting the movement of the volcanic cloud, determining whether ground operations will be affected by ash fall, and estimating how long the drifting volcanic cloud will remain hazardous. A variety of tools have been developed and/or improved over the past several years that provide additional data sources about volcanic hazards that is pertinent to the aviation sector. These include seismic and pressure sensors, ground-based radar and lidar, web cameras, ash dispersion models, and more sensitive satellite sensors that are capable of better detecting volcanic ash, gases and aerosols. Along with these improved capabilities come increased challenges in rapidly assimilating the available data sources, which come from a variety of data providers. In this presentation, examples from the recent large eruptions of Okmok, Kasatochi, and Sarychev Peak volcanoes will be used to demonstrate the challenges faced by hazard response agencies. These eruptions produced volcanic clouds that were dispersed over large regions of the Northern Hemisphere and were observed by pilots and detected by various satellite sensors for several weeks. The disruption to aviation caused by these eruptions further emphasizes the need to improve the real-time characterization of volcanic clouds (altitude, composition, particle size, and concentration) and to better understand the impacts of volcanic ash, gases and aerosols on aircraft, flight crews, and passengers.
NASA Astrophysics Data System (ADS)
Suzuki, Kenji; Nakagawa, Katsuhiro; Kawano, Tetsuya; Mori, Shuichi; Katsumata, Masaki; Yoneyama, Kunio
2017-04-01
During November-December 2015, as a pilot study of the Years of the Maritime and Continent (YMC), a campaign observation over the southwestern coastal land and adjacent sea of Sumatera Island, Indonesia was carried out to examine land-ocean coupling processes in mechanisms of coastal heavy rain. Our videosonde observations were conducted as a part of this campaign for the better understandings of microphysical features in tropical precipitating clouds developed over the Sumatera Island. Videosonde is one of strong tools to measure hydrometeors in clouds directly. It is a balloon-borne radiosonde that acquires images of precipitation particles via a CCD camera. The system has a stroboscopic illumination that provides information on particle size and shape. One of the advantages for the videosonde is to capture images of precipitation particles as they are in the air because the videosonde can obtain particle images without contact. Recorded precipitation particles are classified as raindrops, frozen drops (hail), graupel, ice crystals, or snowflakes on the basis of transparency and shape. Videosondes were launched from BMKG Bengkulu weather station (3.86°S,102.3°E). After the launch of a videosonde, the Range Height Indicator (RHI) scans by a C-band dual-polarimetric radar installed on R/V Mirai, which was approximately 50 km off Sumatera Island, were continuously performed, targeting the videosonde in the precipitating cloud. Eighteen videosondes were launched into various types of tropical precipitating clouds during the Pre-YMC campaign.
Sensitivity of simulated snow cloud properties to mass-diameter parameterizations.
NASA Astrophysics Data System (ADS)
Duffy, G.; Nesbitt, S. W.; McFarquhar, G. M.
2015-12-01
Mass to diameter (m-D) relationships are used in model parameterization schemes to represent ice cloud microphysics and in retrievals of bulk cloud properties from remote sensing instruments. One of the most common relationships, used in the current Global Precipitation Measurement retrieval algorithm for example, assigns the density of snow as a constant tenth of the density of ice (0.1g/m^3). This assumption stands in contrast to the results of derived m-D relationships of snow particles, which imply decreasing particle densities at larger sizes and result in particle masses orders of magnitude below the constant density relationship. In this study, forward simulations of bulk cloud properties (e.g., total water content, radar reflectivity and precipitation rate) derived from measured size distributions using several historical m-D relationships are presented. This expands upon previous studies that mainly focused on smaller ice particles because of the examination of precipitation-sized particles here. In situ and remote sensing data from the GPM Cold season Experiment (GCPEx) and Canadian CloudSAT/Calypso Validation Program (C3VP), both synoptic snowstorm field experiments in southern Ontario, Canada, are used to evaluate the forward simulations against total water content measured by the Nevzorov and Cloud Spectrometer and Impactor (CSI) probe, radar reflectivity measured by a C band ground based radar and a nadir pointing Ku/Ka dual frequency airborne radar, and precipitation rate measured by a 2D video disdrometer. There are differences between the bulk cloud properties derived using varying m-D relations, with constant density assumptions producing results differing substantially from the bulk measured quantities. The variability in bulk cloud properties derived using different m-D relations is compared against the natural variability in those parameters seen in the GCPEx and C3VP field experiments.
Foliage penetration by using 4-D point cloud data
NASA Astrophysics Data System (ADS)
Méndez Rodríguez, Javier; Sánchez-Reyes, Pedro J.; Cruz-Rivera, Sol M.
2012-06-01
Real-time awareness and rapid target detection are critical for the success of military missions. New technologies capable of detecting targets concealed in forest areas are needed in order to track and identify possible threats. Currently, LAser Detection And Ranging (LADAR) systems are capable of detecting obscured targets; however, tracking capabilities are severely limited. Now, a new LADAR-derived technology is under development to generate 4-D datasets (3-D video in a point cloud format). As such, there is a new need for algorithms that are able to process data in real time. We propose an algorithm capable of removing vegetation and other objects that may obfuscate concealed targets in a real 3-D environment. The algorithm is based on wavelets and can be used as a pre-processing step in a target recognition algorithm. Applications of the algorithm in a real-time 3-D system could help make pilots aware of high risk hidden targets such as tanks and weapons, among others. We will be using a 4-D simulated point cloud data to demonstrate the capabilities of our algorithm.
In-Situ Microphysics from the RACORO IOP
McFarquhar, Greg
2013-11-08
These files were generated by Greg McFarquhar and Robert Jackson at the University of Illinois. Please contact mcfarq@atmos.uiuc.edu or rjackso2@atmos.uiuc.edu for more information or for assistance in interpreting the content of these files. We highly recommend that anyone wishing to use these files do so in a collaborative endeavor and we welcome queries and opportunities for collaboration. There are caveats associated with the use of the data which are difficult to thoroughly document and not all products for all time periods have been thoroughly examined. This is a value added data set of the best estimate of cloud microphysical parameters derived using data collected by the cloud microphysical probes installed on the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter during RACORO. These files contain best estimates of liquid size distributions N(D) in terms of droplet diameter D, liquid water content LWC, extinction of liquid drops beta, effective radius of cloud drops (re), total number concentration of droplets NT, and radar reflectivity factor Z at 1 second resolution.
The impact of physical and mental tasks on pilot mental workoad
NASA Technical Reports Server (NTRS)
Berg, S. L.; Sheridan, T. B.
1986-01-01
Seven instrument-rated pilots with a wide range of backgrounds and experience levels flew four different scenarios on a fixed-base simulator. The Baseline scenario was the simplest of the four and had few mental and physical tasks. An activity scenario had many physical but few mental tasks. The Planning scenario had few physical and many mental taks. A Combined scenario had high mental and physical task loads. The magnitude of each pilot's altitude and airspeed deviations was measured, subjective workload ratings were recorded, and the degree of pilot compliance with assigned memory/planning tasks was noted. Mental and physical performance was a strong function of the manual activity level, but not influenced by the mental task load. High manual task loads resulted in a large percentage of mental errors even under low mental task loads. Although all the pilots gave similar subjective ratings when the manual task load was high, subjective ratings showed greater individual differences with high mental task loads. Altitude or airspeed deviations and subjective ratings were most correlated when the total task load was very high. Although airspeed deviations, altitude deviations, and subjective workload ratings were similar for both low experience and high experience pilots, at very high total task loads, mental performance was much lower for the low experience pilots.
ERIC Educational Resources Information Center
Hicks, Terence; Lewis, Leontye; Munn, Geraldine; Jordon, Earlyn; Charles, Kelly
2010-01-01
This study assessed teacher education students' perceptions and satisfaction of their learning experiences concerning an accelerated summer pilot program. In addition, the study provided information on the impact and teaching effectiveness of the accelerated teacher education summer pilot program on participating students. Results from this study…
14 CFR 61.52 - Use of aeronautical experience obtained in ultralight vehicles.
Code of Federal Regulations, 2010 CFR
2010-01-01
... ratings issued under this part: (1) A sport pilot certificate. (2) A flight instructor certificate with a sport pilot rating; (3) A private pilot certificate with a weight-shift-control or powered parachute... provisions of §§ 61.69 and 61.415(e). (c) A person using aeronautical experience obtained in an ultralight...
Direct Observations of Excess Solar Absorption by Clouds
NASA Technical Reports Server (NTRS)
Pilewskie, Peter; Valero, Francisco P. J.
1995-01-01
Aircraft measurements of solar flux in the cloudy tropical atmosphere reveal that solar absorption by clouds is anomalously large when compared to theoretical estimates. The ratio of cloud forcing at an altitude of 20 kilometers to that at the surface is 1.58 rather than 1.0 as predicted by models. These results were derived from a cloud radiation experiment in which identical instrumentation was deployed on coordinated stacked aircraft. These findings indicate a significant difference between measurements and theory and imply that the interaction between clouds and solar radiation is poorly understood.
Cumulus cloud model estimates of trace gas transports
NASA Technical Reports Server (NTRS)
Garstang, Michael; Scala, John; Simpson, Joanne; Tao, Wei-Kuo; Thompson, A.; Pickering, K. E.; Harris, R.
1989-01-01
Draft structures in convective clouds are examined with reference to the results of the NASA Amazon Boundary Layer Experiments (ABLE IIa and IIb) and calculations based on a multidimensional time dependent dynamic and microphysical numerical cloud model. It is shown that some aspects of the draft structures can be calculated from measurements of the cloud environment. Estimated residence times in the lower regions of the cloud based on surface observations (divergence and vertical velocities) are within the same order of magnitude (about 20 min) as model trajectory estimates.
Simulating Visual Attention Allocation of Pilots in an Advanced Cockpit Environment
NASA Technical Reports Server (NTRS)
Frische, F.; Osterloh, J.-P.; Luedtke, A.
2011-01-01
This paper describes the results of experiments conducted with human line pilots and a cognitive pilot model during interaction with a new 40 Flight Management System (FMS). The aim of these experiments was to gather human pilot behavior data in order to calibrate the behavior of the model. Human behavior is mainly triggered by visual perception. Thus, the main aspect was to setup a profile of human pilots' visual attention allocation in a cockpit environment containing the new FMS. We first performed statistical analyses of eye tracker data and then compared our results to common results of familiar analyses in standard cockpit environments. The comparison has shown a significant influence of the new system on the visual performance of human pilots. Further on, analyses of the pilot models' visual performance have been performed. A comparison to human pilots' visual performance revealed important improvement potentials.
Efficient transfer of weather information to the pilot in flight
NASA Technical Reports Server (NTRS)
Mcfarland, R. H.
1982-01-01
Efficient methods for providing weather information to the pilot in flight are summarized. Use of discrete communications channels in the aeronautical, VHF band or subcarriers in the VOR navigation band are considered the best possibilities. Data rates can be provided such that inputs to the ground based transmitters from 2400 band telephone lines are easily accommodated together with additional data. The crucial weather data considered for uplinking are identified as radar reflectivity patterns relating to precipitation, spherics data, hourly sequences, nowcasts, forecasts, cloud top heights with freezing and icing conditions, the critical weather map and satellite maps. NEXRAD, the ground based, Doppler weather radar which will produce an improved weather product also encourages use of an uplink to fully utilize its capability to improve air safety.
Changes in Clouds Under a Combined CO2 Increase and Solar Decrease
NASA Astrophysics Data System (ADS)
Russotto, R. D.; Ackerman, T. P.
2017-12-01
The Geoengineering Model Intercomparison Project (GeoMIP) provides an excellent opportunity to study the response of clouds and the large-scale circulation to opposing solar and greenhouse gas forcings. This study analyzes changes in cloud fraction in 10 fully coupled atmosphere-ocean global climate models in GeoMIP Experiment G1, in which CO2 concentrations are quadrupled and the solar constant is reduced in order to keep global mean temperature at preindustrial levels. There is general agreement among the models that the area coverage of low clouds (below the 680 hPa pressure level) decreases in this experiment compared to preindustrial conditions over most ocean and vegetated land areas. This reduction in low cloud fraction is related to decreases in boundary layer inversion strength over the ocean, and to plant physiological responses to increased CO2. Mid-level clouds (680-440 hPa) and high clouds (< 440 hPa) are reduced over the Atlantic and Pacific Oceans to the north and south of the ITCZ, while high clouds also increase over the center of the ITCZ. These changes are related to a weakening of the seasonal migration of the ITCZ in G1, which happens because the summer hemisphere is preferentially cooled by the solar reduction. To explore the link between clouds and the ITCZ migration, we examine changes in the seasonal cycle of cloud cover and in the instantaneous ITCZ width throughout the year. High cloud fraction increases in the global mean in most models, likely due to upper tropospheric cooling. An analysis of radiative effects using the Approximate Partial Radiation Perturbation method shows that, in the shortwave, cloud changes in G1 have a warming effect in most areas, mainly due to the reduction in low cloud fraction. This effect, along with the warming effect from the increase in high clouds, results in a larger solar reduction being necessary to compensate for the CO2 increase.
NASA Technical Reports Server (NTRS)
Burke, Kelly A.; Wing, David J.; Lewis, Timothy
2013-01-01
Two human-in-the-loop simulation experiments were conducted to investigate allocation of separation assurance functions between ground and air and between humans and automation. The experiments modeled a mixed-operations concept in which aircraft receiving ground-based separation services shared the airspace with aircraft providing their own separation service (i.e., self-separation). The two experiments, one pilot-focused and the other controller-focused, addressed selected key issues of mixed operations and modeling an emergence of NextGen technologies and procedures. This paper focuses on the results of the subjective assessments of pilots collected during the pilot-focused human-in-the-loop simulation, specifically workload and situation awareness. Generally the results revealed that across all conditions, pilots' perceived workload was low to medium, with the highest reported levels of workload occurring when the pilots experienced a loss of separation during the scenario. Furthermore, the results from the workload data and situation awareness data were complimentary such that when pilots reported lower levels of workload they also experienced higher levels of situation awareness.
Enabling Earth Science Through Cloud Computing
NASA Technical Reports Server (NTRS)
Hardman, Sean; Riofrio, Andres; Shams, Khawaja; Freeborn, Dana; Springer, Paul; Chafin, Brian
2012-01-01
Cloud Computing holds tremendous potential for missions across the National Aeronautics and Space Administration. Several flight missions are already benefiting from an investment in cloud computing for mission critical pipelines and services through faster processing time, higher availability, and drastically lower costs available on cloud systems. However, these processes do not currently extend to general scientific algorithms relevant to earth science missions. The members of the Airborne Cloud Computing Environment task at the Jet Propulsion Laboratory have worked closely with the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) mission to integrate cloud computing into their science data processing pipeline. This paper details the efforts involved in deploying a science data system for the CARVE mission, evaluating and integrating cloud computing solutions with the system and porting their science algorithms for execution in a cloud environment.
Cloud Computing Technologies in Writing Class: Factors Influencing Students' Learning Experience
ERIC Educational Resources Information Center
Wang, Jenny
2017-01-01
The proposed interactive online group within the cloud computing technologies as a main contribution of this paper provides easy and simple access to the cloud-based Software as a Service (SaaS) system and delivers effective educational tools for students and teacher on after-class group writing assignment activities. Therefore, this study…
Evaluation of AIRS cloud properties using MPACE data
NASA Astrophysics Data System (ADS)
Wu, Xuebao; Li, Jun; Menzel, W. Paul; Huang, Allen; Baggett, Kevin; Revercomb, Henry
2005-12-01
Retrieval of cloud properties from the Atmospheric Infrared Sounder (AIRS) aboard the NASA Aqua satellite has been investigated. The cloud products from the collocated MODerate resolution Imaging Spectroradiometer (MODIS) data are used to characterize the AIRS sub-pixel cloud information such as cloud phase, cloud coverage, and cloud layer information. A Minimum Residual (MR) approach is used to retrieve cloud microphysical properties once the cloud top pressure (CTP) and effective cloud amount (ECA) are determined from AIRS CO2 absorption channels between 720 and 790 cm-1. The cloud microphysical properties can be retrieved by minimizing the differences between the observations and the calculations using AIRS longwave window channels between 790 and 1130 cm-1. AIRS is used to derive cloud properties during the Mixed Phase Arctic Cloud Experiment (MPACE) field campaign. Comparison with measurements obtained from lidar data is made for a test day, showing that AIRS cloud property retrievals agree with in situ lidar observations. Due to the large solar zenith angle, the MODIS operational retrieval approach is not able to provide cloud microphysics north of Barrow, Alaska; however, AIRS provides cloud microphysical properties with its high spectral resolution IR measurements.
Turbulent Mixing at the Edge of a Cloud
NASA Astrophysics Data System (ADS)
Shaw, Raymond; Beals, Matthew; Fugal, Jacob; Kumar, Bipin; Lu, Jiang; Schumacher, Joerg; Stith, Jeffrey
2013-11-01
Numerical and field experiments have been brought to bear on the question of how atmospheric clouds respond when they experience turbulent mixing with their environment. Simply put, we ask when a cloud is diluted, do all droplets evaporate uniformly (homogeneous mixing) or does a subset of droplets evaporate completely, leaving the remaining droplets unaffected (inhomogeneous mixing)? First, the entrainment of clear air and its subsequent mixing with a filament of cloudy air is studied in DNS that combine the Eulerian description of the turbulent velocity, temperature and vapor fields with a Lagrangian cloud droplet ensemble. The simulations provide guidance on the proper definition of the thermodynamic response time for the Damkoehler number, and demonstrate the transition from inhomogeneous to homogeneous mixing as mixing progresses within the inertial subrange. Second, an airborne digital holographic instrument (Holodec) shows that cloud edges are inhomogeneous at the centimeter scales. In local cloud volumes the droplet size distribution fluctuates strongly in number density but with a nearly unchanging mean droplet diameter, until the fluctuations finally cascade to the centimeter scale, when the droplet diameter begins to respond.
Using Amazon's Elastic Compute Cloud to dynamically scale CMS computational resources
NASA Astrophysics Data System (ADS)
Evans, D.; Fisk, I.; Holzman, B.; Melo, A.; Metson, S.; Pordes, R.; Sheldon, P.; Tiradani, A.
2011-12-01
Large international scientific collaborations such as the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider have traditionally addressed their data reduction and analysis needs by building and maintaining dedicated computational infrastructure. Emerging cloud computing services such as Amazon's Elastic Compute Cloud (EC2) offer short-term CPU and storage resources with costs based on usage. These services allow experiments to purchase computing resources as needed, without significant prior planning and without long term investments in facilities and their management. We have demonstrated that services such as EC2 can successfully be integrated into the production-computing model of CMS, and find that they work very well as worker nodes. The cost-structure and transient nature of EC2 services makes them inappropriate for some CMS production services and functions. We also found that the resources are not truely "on-demand" as limits and caps on usage are imposed. Our trial workflows allow us to make a cost comparison between EC2 resources and dedicated CMS resources at a University, and conclude that it is most cost effective to purchase dedicated resources for the "base-line" needs of experiments such as CMS. However, if the ability to use cloud computing resources is built into an experiment's software framework before demand requires their use, cloud computing resources make sense for bursting during times when spikes in usage are required.
Toward a Big Data Science: A challenge of "Science Cloud"
NASA Astrophysics Data System (ADS)
Murata, Ken T.; Watanabe, Hidenobu
2013-04-01
During these 50 years, along with appearance and development of high-performance computers (and super-computers), numerical simulation is considered to be a third methodology for science, following theoretical (first) and experimental and/or observational (second) approaches. The variety of data yielded by the second approaches has been getting more and more. It is due to the progress of technologies of experiments and observations. The amount of the data generated by the third methodologies has been getting larger and larger. It is because of tremendous development and programming techniques of super computers. Most of the data files created by both experiments/observations and numerical simulations are saved in digital formats and analyzed on computers. The researchers (domain experts) are interested in not only how to make experiments and/or observations or perform numerical simulations, but what information (new findings) to extract from the data. However, data does not usually tell anything about the science; sciences are implicitly hidden in the data. Researchers have to extract information to find new sciences from the data files. This is a basic concept of data intensive (data oriented) science for Big Data. As the scales of experiments and/or observations and numerical simulations get larger, new techniques and facilities are required to extract information from a large amount of data files. The technique is called as informatics as a fourth methodology for new sciences. Any methodologies must work on their facilities: for example, space environment are observed via spacecraft and numerical simulations are performed on super-computers, respectively in space science. The facility of the informatics, which deals with large-scale data, is a computational cloud system for science. This paper is to propose a cloud system for informatics, which has been developed at NICT (National Institute of Information and Communications Technology), Japan. The NICT science cloud, we named as OneSpaceNet (OSN), is the first open cloud system for scientists who are going to carry out their informatics for their own science. The science cloud is not for simple uses. Many functions are expected to the science cloud; such as data standardization, data collection and crawling, large and distributed data storage system, security and reliability, database and meta-database, data stewardship, long-term data preservation, data rescue and preservation, data mining, parallel processing, data publication and provision, semantic web, 3D and 4D visualization, out-reach and in-reach, and capacity buildings. Figure (not shown here) is a schematic picture of the NICT science cloud. Both types of data from observation and simulation are stored in the storage system in the science cloud. It should be noted that there are two types of data in observation. One is from archive site out of the cloud: this is a data to be downloaded through the Internet to the cloud. The other one is data from the equipment directly connected to the science cloud. They are often called as sensor clouds. In the present talk, we first introduce the NICT science cloud. We next demonstrate the efficiency of the science cloud, showing several scientific results which we achieved with this cloud system. Through the discussions and demonstrations, the potential performance of sciences cloud will be revealed for any research fields.
Cloud Detection by Fusing Multi-Scale Convolutional Features
NASA Astrophysics Data System (ADS)
Li, Zhiwei; Shen, Huanfeng; Wei, Yancong; Cheng, Qing; Yuan, Qiangqiang
2018-04-01
Clouds detection is an important pre-processing step for accurate application of optical satellite imagery. Recent studies indicate that deep learning achieves best performance in image segmentation tasks. Aiming at boosting the accuracy of cloud detection for multispectral imagery, especially for those that contain only visible and near infrared bands, in this paper, we proposed a deep learning based cloud detection method termed MSCN (multi-scale cloud net), which segments cloud by fusing multi-scale convolutional features. MSCN was trained on a global cloud cover validation collection, and was tested in more than ten types of optical images with different resolution. Experiment results show that MSCN has obvious advantages over the traditional multi-feature combined cloud detection method in accuracy, especially when in snow and other areas covered by bright non-cloud objects. Besides, MSCN produced more detailed cloud masks than the compared deep cloud detection convolution network. The effectiveness of MSCN make it promising for practical application in multiple kinds of optical imagery.
a Cloud Boundary Detection Scheme Combined with Aslic and Cnn Using ZY-3, GF-1/2 Satellite Imagery
NASA Astrophysics Data System (ADS)
Guo, Z.; Li, C.; Wang, Z.; Kwok, E.; Wei, X.
2018-04-01
Remote sensing optical image cloud detection is one of the most important problems in remote sensing data processing. Aiming at the information loss caused by cloud cover, a cloud detection method based on convolution neural network (CNN) is presented in this paper. Firstly, a deep CNN network is used to extract the multi-level feature generation model of cloud from the training samples. Secondly, the adaptive simple linear iterative clustering (ASLIC) method is used to divide the detected images into superpixels. Finally, the probability of each superpixel belonging to the cloud region is predicted by the trained network model, thereby generating a cloud probability map. The typical region of GF-1/2 and ZY-3 were selected to carry out the cloud detection test, and compared with the traditional SLIC method. The experiment results show that the average accuracy of cloud detection is increased by more than 5 %, and it can detected thin-thick cloud and the whole cloud boundary well on different imaging platforms.
Chen, Ying-Hsien; Hung, Chi-Sheng; Huang, Ching-Chang; Hung, Yu-Chien; Hwang, Juey-Jen; Ho, Yi-Lwun
2017-09-26
Atrial fibrillation (AF) is a common form of arrhythmia that is associated with increased risk of stroke and mortality. Detecting AF before the first complication occurs is a recognized priority. No previous studies have examined the feasibility of undertaking AF screening using a telehealth surveillance system with an embedded cloud-computing algorithm; we address this issue in this study. The objective of this study was to evaluate the feasibility of AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm. We conducted a prospective AF screening study in a nonmetropolitan area using a single-lead electrocardiogram (ECG) recorder. All ECG measurements were reviewed on the telehealth surveillance system and interpreted by the cloud-computing algorithm and a cardiologist. The process of AF screening was evaluated with a satisfaction questionnaire. Between March 11, 2016 and August 31, 2016, 967 ECGs were recorded from 922 residents in nonmetropolitan areas. A total of 22 (2.4%, 22/922) residents with AF were identified by the physician's ECG interpretation, and only 0.2% (2/967) of ECGs contained significant artifacts. The novel cloud-computing algorithm for AF detection had a sensitivity of 95.5% (95% CI 77.2%-99.9%) and specificity of 97.7% (95% CI 96.5%-98.5%). The overall satisfaction score for the process of AF screening was 92.1%. AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm is feasible. ©Ying-Hsien Chen, Chi-Sheng Hung, Ching-Chang Huang, Yu-Chien Hung, Juey-Jen Hwang, Yi-Lwun Ho. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 26.09.2017.
Cloud computing task scheduling strategy based on improved differential evolution algorithm
NASA Astrophysics Data System (ADS)
Ge, Junwei; He, Qian; Fang, Yiqiu
2017-04-01
In order to optimize the cloud computing task scheduling scheme, an improved differential evolution algorithm for cloud computing task scheduling is proposed. Firstly, the cloud computing task scheduling model, according to the model of the fitness function, and then used improved optimization calculation of the fitness function of the evolutionary algorithm, according to the evolution of generation of dynamic selection strategy through dynamic mutation strategy to ensure the global and local search ability. The performance test experiment was carried out in the CloudSim simulation platform, the experimental results show that the improved differential evolution algorithm can reduce the cloud computing task execution time and user cost saving, good implementation of the optimal scheduling of cloud computing tasks.
Reflectivities of uniform and broken marine stratiform clouds
NASA Technical Reports Server (NTRS)
Coakley, James A., Jr.
1990-01-01
Plane-parallel radiative transfer models are often used to estimate the effects of clouds on the earth's energy budget and to retrieve cloud properties from satellite observations. An attempt is made to assess the performance of such models by using AVHRR data collected during the FIRE MARINE Stratus IFO to determine the reflectivities and, in particular, the anisotropy of the reflected radiances for the clouds observed during the field experiment. The intent is to determine the anisotropy for conditions that are overcast and to compare this anisotropy with that produced by the same cloud when broken. The observations are used to quantify aspects of the differences between reflection by plane-parallel clouds and non-planar clouds expected on the basis of theoretical studies.
Observations of marine stratocumulus clouds during FIRE
NASA Technical Reports Server (NTRS)
Albrecht, Bruce A.; Randall, David A.; Nicholls, Stephen
1988-01-01
The First International Satellite Cloud Climatology Project Regional Experiment (FIRE) to study extensive fields of stratocumulus clouds off the coast of California is presented. Measurements on the regional and detailed local scales were taken, allowing for a wide interpretation of the mean, turbulent, microphysical, radiative, and chemical characteristics of stratocumulus. Multiple aircraft and ground-based remote-sensing systems were used to study the time evolution of the boundary layer structure over a three-week period, and probes from tethered balloons were used to measure turbulence and to collect cloud-microphysical and cloud-radiative data. The observations provide a base for studying the generation maintenance and dissipation of stratocumulus clouds, and could aid in developing numerical models and improved methods for retrieving cloud properties by satellite.
Physiological Indices of Pilots' Abilities Under Varying Task Demands.
Wang, Zhen; Zheng, Lingxiao; Lu, Yanyu; Fu, Shan
2016-04-01
This study investigated pilots' ability by examining the effects of flight experience and task demand on physiological reactions, and analyzing the diagnostic meanings underlying correlated parameters. A total of 12 experienced pilots and 12 less experienced pilots performed 4 simulated flight tasks, including normal and emergency situations. Fixation duration (FD), saccade rate (SR), blink rate (BR), heart rate (HR), respiration rate (RR), and respiration amplitude (RA) were measured during the tasks. More experienced pilots adapted their SR flexibly to changing task demands and had significantly lower SR than less experienced pilots during emergency tasks (29.6 ± 20.0 vs. 70.1 ± 67.1 saccades/min). BR, HR, and RR were affected by pilot experience but not by task demand. More experienced pilots had lower BR, HR, and RR than less experienced pilots during both normal tasks (BR: 14.3 ± 13.0 vs. 32.9 ± 25.8 blinks/min; HR: 72.7 ± 7.9 vs. 83.2 ± 7.2 bpm; RR: 15.4 ± 2.1 vs. 19.5 ± 5.2 breaths/min) and emergency tasks (BR: 10.2 ± 5.0 vs. 32.3 ± 20.8 blinks/min; HR: 73.3 ± 7.3 vs. 82.2 ± 11.6 bpm; RR: 15.6 ± 1.9 vs. 18.0 ± 3.2 breaths/min). FD and RA were not sensitive to either flight experience or task demand. Physiological reactions have the potential to reflect pilots' ability from different aspects. SR and BR could indicate pilots' differences in information access strategy. HR and RR could reflect a pilot's physical fitness. These findings are useful for understanding a pilot's ability.
NASA Technical Reports Server (NTRS)
Winker, David M.
1999-01-01
Current uncertainties in the effects of clouds and aerosols on the Earth radiation budget limit our understanding of the climate system and the potential for global climate change. Pathfinder Instruments for Cloud and Aerosol Spaceborne Observations - Climatologie Etendue des Nuages et des Aerosols (PICASSO-CENA) is a recently approved satellite mission within NASA's Earth System Science Pathfinder (ESSP) program which will address these uncertainties with a unique suite of active and passive instruments. The Lidar In-space Technology Experiment (LITE) demonstrated the potential benefits of space lidar for studies of clouds and aerosols. PICASSO-CENA builds on this experience with a payload consisting of a two-wavelength polarization-sensitive lidar, an oxygen A-band spectrometer (ABS), an imaging infrared radiometer (IIR), and a wide field camera (WFC). Data from these instruments will be used to measure the vertical distributions of aerosols and clouds in the atmosphere, as well as optical and physical properties of aerosols and clouds which influence the Earth radiation budget. PICASSO-CENA will be flown in formation with the PM satellite of the NASA Earth Observing System (EOS) to provide a comprehensive suite of coincident measurements of atmospheric state, aerosol and cloud optical properties, and radiative fluxes. The mission will address critical uncertainties iin the direct radiative forcing of aerosols and clouds as well as aerosol influences on cloud radiative properties and cloud-climate radiation feedbacks. PICASSO-CENA is planned for a three year mission, with a launch in early 2003. PICASSO-CENA is being developed within the framework of a collaboration between NASA and CNES.
Atmospheric Rivers Coming to a Cloud Near You
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leung, Ruby
2014-03-29
Learn about the ARM Cloud Aerosol Precipitation Experiment (ACAPEX) field campaign in this short video. Ruby Leung, PNNL's lead scientist on this campaign's observational strategy to monitor precipitation.
Atmospheric Rivers Coming to a Cloud Near You
Leung, Ruby
2018-01-16
Learn about the ARM Cloud Aerosol Precipitation Experiment (ACAPEX) field campaign in this short video. Ruby Leung, PNNL's lead scientist on this campaign's observational strategy to monitor precipitation.
Pilot Non-Conformance to Alerting System Commands During Closely Spaced Parallel Approaches
NASA Technical Reports Server (NTRS)
Pritchett, Amy R.; Hansman, R. John
1997-01-01
Pilot non-conformance to alerting system commands has been noted in general and to a TCAS-like collision avoidance system in a previous experiment. This paper details two experiments studying collision avoidance during closely-spaced parallel approaches in instrument meteorological conditions (IMC), and specifically examining possible causal factors of, and design solutions to, pilot non-conformance.
NASA Astrophysics Data System (ADS)
Zhang, Junhua; Lohmann, Ulrike
2003-08-01
The single column model of the Canadian Centre for Climate Modeling and Analysis (CCCma) climate model is used to simulate Arctic spring cloud properties observed during the Surface Heat Budget of the Arctic Ocean (SHEBA) experiment. The model is driven by the rawinsonde observations constrained European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis data. Five cloud parameterizations, including three statistical and two explicit schemes, are compared and the sensitivity to mixed phase cloud parameterizations is studied. Using the original mixed phase cloud parameterization of the model, the statistical cloud schemes produce more cloud cover, cloud water, and precipitation than the explicit schemes and in general agree better with observations. The mixed phase cloud parameterization from ECMWF decreases the initial saturation specific humidity threshold of cloud formation. This improves the simulated cloud cover in the explicit schemes and reduces the difference between the different cloud schemes. On the other hand, because the ECMWF mixed phase cloud scheme does not consider the Bergeron-Findeisen process, less ice crystals are formed. This leads to a higher liquid water path and less precipitation than what was observed.
Measurement Comparisons Towards Improving the Understanding of Aerosol-Cloud Processing
NASA Astrophysics Data System (ADS)
Noble, Stephen R.
Cloud processing of aerosol is an aerosol-cloud interaction that is not heavily researched but could have implications on climate. The three types of cloud processing are chemical processing, collision and coalescence processing, and Brownian capture of interstitial particles. All types improve cloud condensation nuclei (CCN) in size or hygroscopicity (kappa). These improved CCN affect subsequent clouds. This dissertation focuses on measurement comparisons to improve our observations and understanding of aerosol-cloud processing. Particle size distributions measured at the continental Southern Great Plains (SGP) site were compared with ground based measurements of cloud fraction (CF) and cloud base altitude (CBA). Particle size distributions were described by a new objective shape parameter to define bimodality rather than an old subjective one. Cloudy conditions at SGP were found to be correlated with lagged shape parameter. Horizontal wind speed and regional CF explained 42%+ of this lag time. Many of these surface particle size distributions were influenced by aerosol-cloud processing. Thus, cloud processing may be more widespread with more implications than previously thought. Particle size distributions measured during two aircraft field campaigns (MArine Stratus/stratocumulus Experiment; MASE; and Ice in Cloud Experiment-Tropical; ICE-T) were compared to CCN distributions. Tuning particle size to critical supersaturation revealed hygroscopicity expressed as ? when the distributions were overlain. Distributions near cumulus clouds (ICE-T) had a higher frequency of the same ?s (48% in ICE-T to 42% in MASE) between the accumulation (processed) and Aitken (unprocessed) modes. This suggested physical processing domination in ICE-T. More MASE (stratus cloud) kappa differences between modes pointed to chemical cloud processing. Chemistry measurements made in MASE showed increases in sulfates and nitrates with distributions that were more processed. This supported chemical cloud processing in MASE. This new method to determine kappa provides the needed information without interrupting ambient measurements. MODIS derived cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (re) were compared to the same in situ derived variables from cloud probe measurements of two stratus/stratocumulus cloud campaigns (MASE and Physics Of Stratocumulus Tops; POST). In situ data were from complete vertical cloud penetrations, while MODIS data were from pixels along the aircraft penetration path. Comparisons were well correlated except that MODIS LWP (14-36%) and re (20-30%) were biased high. The LWP bias was from re bias and was not improved by using the vertically stratified assumption. MODIS re bias was almost removed when compared to cloud top maximum in situ re, but, that does not describe re for the full depth of the cloud. COT is validated by in situ COT. High correlations suggest that MODIS variables are useful in self-comparisons such as gradient changes in stratus cloud re during aerosol-cloud processing.
Integration of end-user Cloud storage for CMS analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riahi, Hassen; Aimar, Alberto; Ayllon, Alejandro Alvarez
End-user Cloud storage is increasing rapidly in popularity in research communities thanks to the collaboration capabilities it offers, namely synchronisation and sharing. CERN IT has implemented a model of such storage named, CERNBox, integrated with the CERN AuthN and AuthZ services. To exploit the use of the end-user Cloud storage for the distributed data analysis activity, the CMS experiment has started the integration of CERNBox as a Grid resource. This will allow CMS users to make use of their own storage in the Cloud for their analysis activities as well as to benefit from synchronisation and sharing capabilities to achievemore » results faster and more effectively. It will provide an integration model of Cloud storages in the Grid, which is implemented and commissioned over the world’s largest computing Grid infrastructure, Worldwide LHC Computing Grid (WLCG). In this paper, we present the integration strategy and infrastructure changes needed in order to transparently integrate end-user Cloud storage with the CMS distributed computing model. We describe the new challenges faced in data management between Grid and Cloud and how they were addressed, along with details of the support for Cloud storage recently introduced into the WLCG data movement middleware, FTS3. Finally, the commissioning experience of CERNBox for the distributed data analysis activity is also presented.« less
Integration of end-user Cloud storage for CMS analysis
Riahi, Hassen; Aimar, Alberto; Ayllon, Alejandro Alvarez; ...
2017-05-19
End-user Cloud storage is increasing rapidly in popularity in research communities thanks to the collaboration capabilities it offers, namely synchronisation and sharing. CERN IT has implemented a model of such storage named, CERNBox, integrated with the CERN AuthN and AuthZ services. To exploit the use of the end-user Cloud storage for the distributed data analysis activity, the CMS experiment has started the integration of CERNBox as a Grid resource. This will allow CMS users to make use of their own storage in the Cloud for their analysis activities as well as to benefit from synchronisation and sharing capabilities to achievemore » results faster and more effectively. It will provide an integration model of Cloud storages in the Grid, which is implemented and commissioned over the world’s largest computing Grid infrastructure, Worldwide LHC Computing Grid (WLCG). In this paper, we present the integration strategy and infrastructure changes needed in order to transparently integrate end-user Cloud storage with the CMS distributed computing model. We describe the new challenges faced in data management between Grid and Cloud and how they were addressed, along with details of the support for Cloud storage recently introduced into the WLCG data movement middleware, FTS3. Finally, the commissioning experience of CERNBox for the distributed data analysis activity is also presented.« less
NASA Astrophysics Data System (ADS)
Chen, H.; Schmidt, S.; Coddington, O.; Wind, G.; Bucholtz, A.; Segal-Rosenhaimer, M.; LeBlanc, S. E.
2017-12-01
Cloud Optical Parameters (COPs: e.g., cloud optical thickness and cloud effective radius) and surface albedo are the most important inputs for determining the Cloud Radiative Effect (CRE) at the surface. In the Arctic, the COPs derived from passive remote sensing such as from the Moderate Resolution Imaging Spectroradiometer (MODIS) are difficult to obtain with adequate accuracy owing mainly to insufficient knowledge about the snow/ice surface, but also because of the low solar zenith angle. This study aims to validate COPs derived from passive remote sensing in the Arctic by using aircraft measurements collected during two field campaigns based in Fairbanks, Alaska. During both experiments, ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) and ARISE (Arctic Radiation-IceBridge Sea and Ice Experiment), the Solar Spectral Flux Radiometer (SSFR) measured upwelling and downwelling shortwave spectral irradiances, which can be used to derive surface and cloud albedo, as well as the irradiance transmitted by clouds. We assess the variability of the Arctic sea ice/snow surfaces albedo through these aircraft measurements and incorporate this variability into cloud retrievals for SSFR. We then compare COPs as derived from SSFR and MODIS for all suitable aircraft underpasses of the satellites. Finally, the sensitivities of the COPs to surface albedo and solar zenith angle are investigated.
Why Did the 2010 Eyjafjallajokull Volcanic Eruption Cloud Last So Long?
NASA Astrophysics Data System (ADS)
Jellinek, M.; Carazzo, G.
2013-12-01
The global economic consequences of the relatively small Eyjafjallajokull eruption in the spring of 2010 caught the world off guard. That the eruption cloud lasted for several months rather than weeks, efficiently disrupting air travel and the holiday plans of thousands of tourists, drew arguably more attention and a certainly garnered a highly emotional response. The longevity of this eruption cloud was touted to be "an anomaly". However, this anomaly nearly repeated itself the following year in the form of the 2011 Puyehue-Cordon Caulle eruption cloud. A major reason that the behavior of the 2010 Eyjafjallajokul cloud was surprising is that "standard" models for ash sedimentation (i.e., heavy particles fall out of the cloud faster than light particles) are incomplete. Observations of the 2010 Eyjafjallajokull, as well as the structure of atmospheric aerosol clouds from the 1991 Mt Pinatubo event, suggest that an additional key process in addition to particle settling is the production of internal layering. We use analog experiments on turbulent particle-laden umbrella clouds and simple models to show that this layering occurs where natural convection driven by particle sedimentation and the differential diffusion of primarily heat and fine particles give rise to a large scale instability leading to this layering. This 'particle diffusive convection' strongly influences cloud longevity where volcanic umbrella clouds are enriched in fine ash. More generally, volcanic cloud residence times will depend on ash fluxes related to both individual particle settling and diffusive convection. We discuss a new sedimentation model that includes both contributions to the particle flux and explains the the rate of change of particle concentration in the 1982 El Chichon, 1991 Mt Pinatubo and 1992 Mt Spurr ash-clouds. Examples of periodic layering in volcanic clouds compared with experiments in which periodic layering emerges as a result of buoyancy effects related to a particle-salt double diffusive instability.
Investigation of plasma contactors for use with orbiting wires
NASA Technical Reports Server (NTRS)
Estes, Robert D.; Grossi, Mario D.; Hohlfeld, Robert
1987-01-01
The proposed Shuttle-based short tether experiments with hollow cathodes have the potential for providing important data that will not be obtained in long tether experiments. A critical property for hollow cathode effectiveness as a plasma contactor is the cross magnetic field conductivity of the emitted plasma. The different effects of hollow cathode cloud overlap in the cases of motion-driven and battery-driven operation are emphasized. The calculations presented on the size and shape of the hollow cathode cloud improve the qualitative picture of hollow cathodes in low Earth orbit and provide estimates of time constants for establishing the fully-expanded cloud. The magnetic boundary value problem calculations indicate the way in which the magnetic field will effect the shape of the cloud by resisting expansion in the direction perpendicular to the field. The large-scale interactions of the system were also considered. It was concluded that recent plasma chamber experiments by Stenzel and Urrutia do not model an electrodynamic tether well enough to apply the results to tethered system behavior. Orbiting short tether experiments on hollow cathodes will provide critical information on hollow cathode performance and the underlying physics that cannot be obtained any other way. Experiments should be conducted as soon as funding and a suitable space vehicle are available.
The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Flight Experiment
NASA Technical Reports Server (NTRS)
Williams, Daniel M.; Murdoch, Jennifer L.; Adams, Catherine H.
2005-01-01
This paper provides a summary of conclusions from the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) Flight Experiment which NASA conducted to determine pilot acceptability of the HVO concept for normal conditions. The SATS HVO concept improves efficiency at non-towered, non-radar airports in Instrument Meteorological Conditions (IMC) while achieving a level of safety equal to today s system. Reported are results from flight experiment data that indicate that the SATS HVO concept is viable. The success of the SATS HVO concept is based on acceptable pilot workload, performance, and subjective criteria when compared to the procedural control operations in use today at non-towered, non-radar controlled airfields in IMC. The HVO Flight Experiment, flown on NASA's Cirrus SR22, used a subset of the HVO Simulation Experiment scenarios and evaluation pilots in order to validate the simulation experiment results. HVO and Baseline (today s system) scenarios flown included: single aircraft arriving for a GPS non-precision approach; aircraft arriving for the approach with multiple traffic aircraft; and aircraft arriving for the approach with multiple traffic aircraft and then conducting a missed approach. Results reveal that all twelve low-time instrument-rated pilots preferred SATS HVO when compared to current procedural separation operations. These pilots also flew the HVO procedures safely and proficiently without additional workload in comparison to today s system (Baseline). Detailed results of pilot flight technical error, and their subjective assessments of workload and situation awareness are presented in this paper.
NASA Technical Reports Server (NTRS)
1994-01-01
Passing through some of the trailer clouds of an overcast sky which temporarily postponed its launch, the Space Shuttle Discovery heads for its 19th Earth orbital flight. Several kilometers away, astronaut John H. Casper, Jr., who took this picture, was piloting the Shuttle Training Aircraft (STA) from which the launch and landing area weather was being monitored. Onboard Discovery were astronauts Richard N. Richards, L. Blaine Hammond, Jr., Mark C. Lee, Carl J. Meade, Susan J. Helms, and Jerry M. Linenger.
2008-03-01
fic nstances wthn some gven text, speech, or behavor (Mles & Huberman , 1994). Multple nstances of a sngle factor then consttute a “theme...Aerospace Medcne. Mles, M.B., and Huberman , A.M. (1994). Qualitative data analysis. Thousand Oaks, CA: Sage. Mlgram, S. (2004). Obedience to authority...personal minimum for GA VFR visibility ________ statute miles 12. Your normal personal minimum for GA VFR cloud ceiling ________ feet AGL For
2015-10-01
likely outcomes and make decisions; however, that is a fundamentally different dy- namic than a true learning process. Preprogrammed assumptions and design ...ISR, targeting, forward air control, laser designation , weapons delivery, battle damage assessment ISR, targeting acquisition, and attack...KTAS 400 KTAS Weapons Payload N/A N/A 2 Hellfire missiles 4 Hellfire missiles 14 Hellfire or 4 Hellfire and 2x GBU -12 or 2 Joint Direct Attack
Pasha, Terouz; Stokes, Paul R A
2018-01-01
The 2015 Germanwings Flight 9525 disaster, in which 150 people were killed after the co-pilot may have intentionally crashed the plane in a suicide attempt, highlights the importance of better understanding the mental health of commercial airline pilots. However, there have been few systematic reviews investigating the topic of mental health in commercial aviation. This systematic review aims to identify the types and prevalence of mental health disorders that commercial airline pilots experience with a focus on mood disorders and suicide risk. A systematic literature search was performed using PubMed, EMBASE, and PsycINFO databases. Eligible studies were assessed and data was extracted and analyzed. 20 studies were identified. The prevalence of depression experienced by commercial airline pilots in this review ranged from 1.9% to 12.6%. Factors that negatively impacted the mental health of pilots included substance abuse, experiencing verbal or sexual abuse, disruption in sleep circadian rhythms and fatigue. This systematic review identifies that commercial airline pilots may experience depression at least as frequently as the general population. Commercial airline pilots experience occupational stressors, such as disrupted circadian rhythms and fatigue which may increase risks of developing mood disorders. Most studies identified in this review were cross-sectional in nature with substantial limitations. There is a clear need for further higher quality longitudinal studies to better understand the mental health of commercial airline pilots.
Expertise and responsibility effects on pilots' reactions to flight deck alerts in a simulator.
Zheng, Yiyuan; Lu, Yanyu; Yang, Zheng; Fu, Shan
2014-11-01
Flight deck alerts provide system malfunction information designed to lead corresponding pilot reactions aimed at guaranteeing flight safety. This study examined the roles of expertise and flight responsibility and their relationship to pilots' reactions to flight deck alerts. There were 17 pilots composing 12 flight crews that were assigned into pairs according to flight hours and responsibilities. The experiment included 9 flight scenarios and was carried out in a CRJ-200 flight simulator. Pilot performance was recorded by a wide angle video camera, and four kinds of reactions to alerts were defined for analysis. Pilots tended to have immediate reactions to uninterrupted cautions, with a turning off rate as high as 75%. However, this rate decreased sharply when pilots encountered interrupted cautions and warnings; they also exhibited many wrong reactions to warnings. Pilots with more expertise had more reactions to uninterrupted cautions than those with less expertise, both as pilot flying and pilot monitoring. Meanwhile, the pilot monitoring, regardless of level of expertise, exhibited more reactions than the pilot flying. In addition, more experienced pilots were more likely to have wrong reactions to warnings while acting as the monitoring pilot. These results suggest that both expertise and flight responsibility influence pilots' reactions to alerts. Considering crew pairing strategy, when a pilot flying is a less experienced pilot, a more experience pilot is suggested to be the monitoring pilot. The results of this study have implications for understanding pilots' behaviors to flight deck alerts, calling for specialized training and design of approach alarms on the flight deck.
NASA Astrophysics Data System (ADS)
Susskind, J.; Rosenberg, R. I.
2016-12-01
The GEOS-5 Data Assimilation System (DAS) generates a global analysis every six hours by combining the previous six hour forecast for that time period with contemporaneous observations. These observations include in-situ observations as well as those taken by satellite borne instruments, such as AIRS/AMSU on EOS Aqua and CrIS/ATMS on S-NPP. Operational data assimilation methodology assimilates observed channel radiances Ri for IR sounding instruments such as AIRS and CrIS, but only for those channels i in a given scene whose radiances are thought to be unaffected by clouds. A limitation of this approach is that radiances in most tropospheric sounding channels are affected by clouds under partial cloud cover conditions, which occurs most of the time. The AIRS Science Team Version-6 retrieval algorithm generates cloud cleared radiances (CCR's) for each channel in a given scene, which represent the radiances AIRS would have observed if the scene were cloud free, and then uses them to determine quality controlled (QC'd) temperature profiles T(p) under all cloud conditions. There are potential advantages to assimilate either AIRS QC'd CCR's or QC'd T(p) instead of Ri in that the spatial coverage of observations is greater under partial cloud cover. We tested these two alternate data assimilation approaches by running three parallel data assimilation experiments over different time periods using GEOS-5. Experiment 1 assimilated all observations as done operationally, Experiment 2 assimilated QC'd values of AIRS CCRs in place of AIRS radiances, and Experiment 3 assimilated QC'd values of T(p) in place of observed radiances. Assimilation of QC'd AIRS T(p) resulted in significant improvement in seven day forecast skill compared to assimilation of CCR's or assimilation of observed radiances, especially in the Southern Hemisphere Extra-tropics.
In situ observations of Arctic cloud properties across the Beaufort Sea marginal ice zone
NASA Astrophysics Data System (ADS)
Corr, C.; Moore, R.; Winstead, E.; Thornhill, K. L., II; Crosbie, E.; Ziemba, L. D.; Beyersdorf, A. J.; Chen, G.; Martin, R.; Shook, M.; Corbett, J.; Smith, W. L., Jr.; Anderson, B. E.
2016-12-01
Clouds play an important role in Arctic climate. This is particularly true over the Arctic Ocean where feedbacks between clouds and sea-ice impact the surface radiation budget through modifications of sea-ice extent, ice thickness, cloud base height, and cloud cover. This work summarizes measurements of Arctic cloud properties made aboard the NASA C-130 aircraft over the Beaufort Sea during ARISE (Arctic Radiation - IceBridge Sea&Ice Experiment) in September 2014. The influence of surface-type on cloud properties is also investigated. Specifically, liquid water content (LWC), droplet concentrations, and droplet size distributions are compared for clouds sampled over three distinct regimes in the Beaufort Sea: 1) open water, 2) the marginal ice zone, and 3) sea-ice. Regardless of surface type, nearly all clouds intercepted during ARISE were liquid-phase clouds. However, differences in droplet size distributions and concentrations were evident for the surface types; clouds over the MIZ and sea-ice generally had fewer and larger droplets compared to those over open water. The potential implication these results have for understanding cloud-surface albedo climate feedbacks in Arctic are discussed.
Life and Microgravity Sciences Spacelab Mission: Human Research Pilot Study
NASA Technical Reports Server (NTRS)
Arnaud, Sara B. (Editor); Walker, Karen R. (Editor); Hargens, Alan (Editor)
1996-01-01
The Life Sciences, Microgravity Science and Spacelab Mission contains a number of human experiments directed toward identifying the functional, metabolic and neurological characteristics of muscle weakness and atrophy during space flight. To ensure the successful completion of the flight experiments, a ground-based pilot study, designed to mimic the flight protocols as closely as possible, was carried out in the head-down tilt bed rest model. This report records the rationales, procedures, preliminary results and estimated value of the pilot study, the first of its kind, for 12 of the 13 planned experiments in human research. The bed rest study was conducted in the Human Research Facility at Ames Research Center from July 11 - August 28, 1995. Eight healthy male volunteers performed the experiments before, during and after 17 days bed rest. The immediate purposes of this simulation were to integrate the experiments, provide data in a large enough sample for publication of results, enable investigators to review individual experiments in the framework of a multi-disciplinary study and relay the experience of the pilot study to the mission specialists prior to launch.
A study of surface temperatures, clouds and net radiation
NASA Technical Reports Server (NTRS)
Dhuria, Harbans
1994-01-01
The study is continuing and it is focused on examining seasonal relationships between climate parameters such as the surface temperatures, the net radiation and cloud types and amount on a global basis for the period February 1985 to January 1987. The study consists of an analysis of the combined Earth Radiation Budget Experiment (ERBE) and International Satellite Cloud Climatology Program (ISCCP) products. The main emphasis is on obtaining the information about the interactions and relationships of Earth Radiation Budget parameters, cloud and temperature information. The purpose is to gain additional qualitative and quantitative insight into the cloud climate relationship.
Cloud cover determination in polar regions from satellite imagery
NASA Technical Reports Server (NTRS)
Barry, R. G.; Key, J. R.; Maslanik, J. A.
1988-01-01
The principal objectives of this project are: to develop suitable validation data sets to evaluate the effectiveness of the ISCCP operational algorithm for cloud retrieval in polar regions and to validate model simulations of polar cloud cover; to identify limitations of current procedures for varying atmospheric surface conditions, and to explore potential means to remedy them using textural classifiers: and to compare synoptic cloud data from a control run experiment of the Goddard Institute for Space Studies (GISS) climate model 2 with typical observed synoptic cloud patterns. Current investigations underway are listed and the progress made to date is summarized.
Microphysical Timescales in Clouds and their Application in Cloud-Resolving Modeling
NASA Technical Reports Server (NTRS)
Zeng, Xiping; Tao, Wei-Kuo; Simpson, Joanne
2007-01-01
Independent prognostic variables in cloud-resolving modeling are chosen on the basis of the analysis of microphysical timescales in clouds versus a time step for numerical integration. Two of them are the moist entropy and the total mixing ratio of airborne water with no contributions from precipitating particles. As a result, temperature can be diagnosed easily from those prognostic variables, and cloud microphysics be separated (or modularized) from moist thermodynamics. Numerical comparison experiments show that those prognostic variables can work well while a large time step (e.g., 10 s) is used for numerical integration.
Classification of Clouds in Satellite Imagery Using Adaptive Fuzzy Sparse Representation.
Jin, Wei; Gong, Fei; Zeng, Xingbin; Fu, Randi
2016-12-16
Automatic cloud detection and classification using satellite cloud imagery have various meteorological applications such as weather forecasting and climate monitoring. Cloud pattern analysis is one of the research hotspots recently. Since satellites sense the clouds remotely from space, and different cloud types often overlap and convert into each other, there must be some fuzziness and uncertainty in satellite cloud imagery. Satellite observation is susceptible to noises, while traditional cloud classification methods are sensitive to noises and outliers; it is hard for traditional cloud classification methods to achieve reliable results. To deal with these problems, a satellite cloud classification method using adaptive fuzzy sparse representation-based classification (AFSRC) is proposed. Firstly, by defining adaptive parameters related to attenuation rate and critical membership, an improved fuzzy membership is introduced to accommodate the fuzziness and uncertainty of satellite cloud imagery; secondly, by effective combination of the improved fuzzy membership function and sparse representation-based classification (SRC), atoms in training dictionary are optimized; finally, an adaptive fuzzy sparse representation classifier for cloud classification is proposed. Experiment results on FY-2G satellite cloud image show that, the proposed method not only improves the accuracy of cloud classification, but also has strong stability and adaptability with high computational efficiency.
Ozone Research with Advanced Cooperative Lidar Experiment (ORACLE) Implementation Study
NASA Technical Reports Server (NTRS)
Stadler, John H.; Browell, Edward V.; Ismail, Syed; Dudelzak, Alexander E.; Ball, Donald J.
1998-01-01
New technological advances have made possible new active remote sensing capabilities from space. Utilizing these technologies, the Ozone Research with Advanced Cooperative Lidar Experiment (ORACLE) will provide high spatial resolution measurements of ozone, clouds and aerosols in the stratosphere and lower troposphere. Simultaneous measurements of ozone, clouds and aerosols will assist in the understanding of global change, atmospheric chemistry and meteorology.
Schmied, Virginia; Myors, Karen; Wills, Jo; Cooke, Margaret
2002-01-01
This paper describes a pilot antenatal education program intended to better prepare couples for the early weeks of lifestyle changes and parenting. Eight weeks after birth, data were collected by questionnaire from 19 couples who participated in a pilot program and from 14 couples who were enrolled in a routine hospital program. Women in the pilot program were significantly more satisfied with their experience of parenthood. Facilitated gender-specific discussion groups formed a key strategy in the pilot program. PMID:17273305
Flight-test experience in digital control of a remotely piloted vehicle.
NASA Technical Reports Server (NTRS)
Edwards, J. W.
1972-01-01
The development of a remotely piloted vehicle system consisting of a remote pilot cockpit and a ground-based digital computer coupled to the aircraft through telemetry data links is described. The feedback control laws are implemented in a FORTRAN program. Flight-test experience involving high feedback gain limits for attitude and attitude rate feedback variables, filtering of sampled data, and system operation during intermittent telemetry data link loss is discussed. Comparisons of closed-loop flight tests with analytical calculations, and pilot comments on system operation are included.
NASA EVEX Experiment Launches from the Marshall Islands
2017-12-08
Red and white vapor clouds filled the skies over the Marshall Islands as part of NASA’s Equatorial Vortex Experiment (EVEX). The red cloud was formed by the release of lithium vapor and the white tracer clouds were formed by the release of trimethyl aluminum (TMA). These clouds allowed scientists on the ground from various locations in the Marshall Islands to observe the neutral winds in the ionosphere. Credit: NASA/Jon Grant --- The Equatorial Vortex Experiment (EVEX) was successfully conducted during the early morning hours (eastern time) May 7 from Roi Namur, Republic of the Marshall Islands. A NASA Terrier-Oriole sounding rocket was launched at 3:39 a.m. EDT and was followed by a launch of Terrier-Improved Malemute sounding rocket 90 seconds later. Preliminary indications are that both rockets released their vapor clouds of lithium or trimethyl aluminum, which were observed from various locations in the area, and all science instruments on the rockets worked as planned. More information on EVEX can be found at www.nasa.gov/mission_pages/sounding-rockets/news/evex.html These were the second and third rockets of four planned for launch during this year’s campaign in the Marshall Islands. The first and fourth rockets are supporting the Metal Oxide Space Cloud experiment (MOSC), which is studying radio frequency propagation. NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Eleven quick tips for architecting biomedical informatics workflows with cloud computing.
Cole, Brian S; Moore, Jason H
2018-03-01
Cloud computing has revolutionized the development and operations of hardware and software across diverse technological arenas, yet academic biomedical research has lagged behind despite the numerous and weighty advantages that cloud computing offers. Biomedical researchers who embrace cloud computing can reap rewards in cost reduction, decreased development and maintenance workload, increased reproducibility, ease of sharing data and software, enhanced security, horizontal and vertical scalability, high availability, a thriving technology partner ecosystem, and much more. Despite these advantages that cloud-based workflows offer, the majority of scientific software developed in academia does not utilize cloud computing and must be migrated to the cloud by the user. In this article, we present 11 quick tips for architecting biomedical informatics workflows on compute clouds, distilling knowledge gained from experience developing, operating, maintaining, and distributing software and virtualized appliances on the world's largest cloud. Researchers who follow these tips stand to benefit immediately by migrating their workflows to cloud computing and embracing the paradigm of abstraction.
Point-Cloud Compression for Vehicle-Based Mobile Mapping Systems Using Portable Network Graphics
NASA Astrophysics Data System (ADS)
Kohira, K.; Masuda, H.
2017-09-01
A mobile mapping system is effective for capturing dense point-clouds of roads and roadside objects Point-clouds of urban areas, residential areas, and arterial roads are useful for maintenance of infrastructure, map creation, and automatic driving. However, the data size of point-clouds measured in large areas is enormously large. A large storage capacity is required to store such point-clouds, and heavy loads will be taken on network if point-clouds are transferred through the network. Therefore, it is desirable to reduce data sizes of point-clouds without deterioration of quality. In this research, we propose a novel point-cloud compression method for vehicle-based mobile mapping systems. In our compression method, point-clouds are mapped onto 2D pixels using GPS time and the parameters of the laser scanner. Then, the images are encoded in the Portable Networking Graphics (PNG) format and compressed using the PNG algorithm. In our experiments, our method could efficiently compress point-clouds without deteriorating the quality.
Eleven quick tips for architecting biomedical informatics workflows with cloud computing
Moore, Jason H.
2018-01-01
Cloud computing has revolutionized the development and operations of hardware and software across diverse technological arenas, yet academic biomedical research has lagged behind despite the numerous and weighty advantages that cloud computing offers. Biomedical researchers who embrace cloud computing can reap rewards in cost reduction, decreased development and maintenance workload, increased reproducibility, ease of sharing data and software, enhanced security, horizontal and vertical scalability, high availability, a thriving technology partner ecosystem, and much more. Despite these advantages that cloud-based workflows offer, the majority of scientific software developed in academia does not utilize cloud computing and must be migrated to the cloud by the user. In this article, we present 11 quick tips for architecting biomedical informatics workflows on compute clouds, distilling knowledge gained from experience developing, operating, maintaining, and distributing software and virtualized appliances on the world’s largest cloud. Researchers who follow these tips stand to benefit immediately by migrating their workflows to cloud computing and embracing the paradigm of abstraction. PMID:29596416
Global Single and Multiple Cloud Classification with a Fuzzy Logic Expert System
NASA Technical Reports Server (NTRS)
Welch, Ronald M.; Tovinkere, Vasanth; Titlow, James; Baum, Bryan A.
1996-01-01
An unresolved problem in remote sensing concerns the analysis of satellite imagery containing both single and multiple cloud layers. While cloud parameterizations are very important both in global climate models and in studies of the Earth's radiation budget, most cloud retrieval schemes, such as the bispectral method used by the International Satellite Cloud Climatology Project (ISCCP), have no way of determining whether overlapping cloud layers exist in any group of satellite pixels. Coakley (1983) used a spatial coherence method to determine whether a region contained more than one cloud layer. Baum et al. (1995) developed a scheme for detection and analysis of daytime multiple cloud layers using merged AVHRR (Advanced Very High Resolution Radiometer) and HIRS (High-resolution Infrared Radiometer Sounder) data collected during the First ISCCP Regional Experiment (FIRE) Cirrus 2 field campaign. Baum et al. (1995) explored the use of a cloud classification technique based on AVHRR data. This study examines the feasibility of applying the cloud classifier to global satellite imagery.
NASA Astrophysics Data System (ADS)
Long, Yoann; Charbouillot, Tiffany; Brigante, Marcello; Mailhot, Gilles; Delort, Anne-Marie; Chaumerliac, Nadine; Deguillaume, Laurent
2013-10-01
Currently, cloud chemistry models are including more detailed and explicit multiphase mechanisms based on laboratory experiments that determine such values as kinetic constants, stability constants of complexes and hydration constants. However, these models are still subject to many uncertainties related to the aqueous chemical mechanism they used. Particularly, the role of oxidants such as iron and hydrogen peroxide in the oxidative capacity of the cloud aqueous phase has typically never been validated against laboratory experimental data. To fill this gap, we adapted the M2C2 model (Model of Multiphase Cloud Chemistry) to simulate irradiation experiments on synthetic aqueous solutions under controlled conditions (e.g., pH, temperature, light intensity) and for actual cloud water samples. Various chemical compounds that purportedly contribute to the oxidative budget in cloud water (i.e., iron, oxidants, such as hydrogen peroxide: H2O2) were considered. Organic compounds (oxalic, formic and acetic acids) were taken into account as target species because they have the potential to form iron complexes and are good indicators of the oxidative capacity of the cloud aqueous phase via their oxidation in this medium. The range of concentrations for all of the chemical compounds evaluated was representative of in situ measurements. Numerical outputs were compared with experimental data that consisted of a time evolution of the concentrations of the target species. The chemical mechanism in the model describing the “oxidative engine” of the HxOy/iron (HxOy = H2O2, HO2rad /O2rad - and HOrad ) chemical system was consistent with laboratory measurements. Thus, the degradation of the carboxylic acids evaluated was closely reproduced by the model. However, photolysis of the Fe(C2O4)+ complex needs to be considered in cloud chemistry models for polluted conditions (i.e., acidic pH) to correctly reproduce oxalic acid degradation. We also show that iron and formic acid lead to a stable complex whose photoreactivity has currently not been investigated. The updated aqueous chemical mechanism was compared with data from irradiation experiments using natural cloud water. The new reactions considered in the model (i.e., iron complex formation with oxalic and formic acids) correctly reproduced the experimental observations.
Danish Health Professionals' Experiences of Being Coached: A Pilot Study
ERIC Educational Resources Information Center
Ammentorp, Jette; Jensen, Hanne Irene; Uhrenfeldt, Lisbeth
2013-01-01
Introduction: In recent years, coaching, as a supplement to professional development, has received increased attention, especially in nursing. Still, only little is known about how health professionals experience participating in coaching sessions. The purpose of this pilot study was to describe and analyze health professionals' experiences from…
14 CFR 61.163 - Aeronautical experience: Powered-lift category rating.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical experience: Powered-lift... Transport Pilots § 61.163 Aeronautical experience: Powered-lift category rating. (a) A person who is applying for an airline transport pilot certificate with a powered-lift category rating must have at least...
14 CFR 61.163 - Aeronautical experience: Powered-lift category rating.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aeronautical experience: Powered-lift... Transport Pilots § 61.163 Aeronautical experience: Powered-lift category rating. (a) A person who is applying for an airline transport pilot certificate with a powered-lift category rating must have at least...
Assistive Solutions in Practice: Experiences from AAL Pilot Regions in Austria.
Ates, Nesrin; Aumayr, Georg; Drobics, Mario; Förster, Kristina Maria; Frauenberger, Christopher; Garschall, Markus; Kofler, Manfred; Krainer, Daniela; Kropf, Johannes; Majcen, Kurt; Oberzaucher, Johannes; Piazolo, Felix; Rzepka, Angelika; Sauskojus, Julia; Schneider, Cornelia; Stainer-Hochgatterer, Andreas; Sturm, Nadine; Waibel, Uli; Willner, Viktoria
2017-01-01
Since 2012 six AAL pilot regions were launched in Austria. The main goal of these pilot regions is to evaluate the impact of AAL technologies in daily use considering the entire value chain. Additionally, go-to market strategies for assistive technologies based on an involvement of all relevant stakeholders are developed. Within this paper an overview of the specific objectives, approaches and the status of all Austrian AAL pilot regions is given. Taking into account the different experiences of the different pilot regions, specific challenges in establishing, implementing and sustaining pilot region projects are discussed and lessons-learned are presented. Results show that a careful planning of all project phases taking into account available resources is crucial for the successful implementation of an AAL pilot region. In particular, this applies to all activities related to the active involvement of end-users.
Near-field monitoring of the Eyjafjallajökull eruption cloud
NASA Astrophysics Data System (ADS)
Bjornsson, H.; Pedersen, G. N.; Arason, P.; Karlsdottir, S.; Vogfjord, K. S.; Thorsteinsson, H.; Palmason, B.; Sigurdsson, A.
2010-12-01
When the ice capped Eyjafjallajökull volcano erupted in April 2010 the Icelandic Meteorological Office (IMO) employed range of observation systems to monitor the eruption cloud and the progress of the eruption. The main tool for monitoring the volcanic cloud was a C-band weather radar located at Keflavik international airport, about 150 km from the volcano. Radar monitoring was supported by visual observations, on-site and from a network of web-cameras. Airborne observations allowed for detailed examination of the plume, and pilot reports proved to be an extremely useful aid in verifying the radar data. Furthermore, data from lightning sensors and radiosondes was used to supplement information on plume height. Satellite images, from several frequency bands and both polar as well as geostationary satellites were used to track the orientation of the eruption cloud, and brightness temperature difference was used to estimate far field ash dispersal. Ash fall monitoring and meteorological observations supplemented with atmospheric reanalysis and wind forecasts were used to track local ash dispersal. Information from these data sources was combined with geophysical and hydrological measurements (seismic, GPS, strain and river flow gauges) made by the IMO, the Earth Institute of the University of Iceland and other institutions. The data generated by these different observation types gives a consistent picture of the progression of the eruption and reveals interesting connections. For example, volcanic tremors tended to be inversly related to the eruption cloud height, increasing tremors were associated lower plume height and reduced eruption strength. Furthermore, the occurrence of lighting seems to be explained by both sufficiently strong plume and cold ambient air. Wind also had a clear effect on the eruption cloud height. In general, simple scaling laws for the relationship between the emission rate of the volcano, and the height of the eruption do not seem to explain all the height variations in the eruption cloud.
2010-06-01
photograph of Owens Valley during the event. There is an isolated cloud with a leading edge over the center of the valley, consistent with a lenticular ...tom) Lenticular cloud over Owens Valley at 2100 UTC looking SE (photo by Alex Reinecke). vations and there is no separation of the surface wester- lies...southwestern US. On the other hand, satellite also shows clouds organized in bands parallel to the mountains and lenticular clouds were present over Owens
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matthew R. Kumjian; Giangrande, Scott E.; Mishra, Subashree
Polarimetric radar observations increasingly are used to understand cloud microphysical processes, which is critical for improving their representation in cloud and climate models. In particular, there has been recent focus on improving representations of ice collection processes (e.g., aggregation, riming), as these influence precipitation rate, heating profiles, and ultimately cloud life cycles. However, distinguishing these processes using conventional polarimetric radar observations is difficult, as they produce similar fingerprints. This necessitates improved analysis techniques and integration of complementary data sources. Furthermore, the Midlatitude Continental Convective Clouds Experiment (MC3E) provided such an opportunity.
Coherent forward broadening in cold atom clouds
NASA Astrophysics Data System (ADS)
Sutherland, R. T.; Robicheaux, F.
2016-02-01
It is shown that homogeneous line-broadening in a diffuse cold atom cloud is proportional to the resonant optical depth of the cloud. Furthermore, it is demonstrated how the strong directionality of the coherent interactions causes the cloud's spectra to depend strongly on its shape, even when the cloud is held at constant densities. These two numerical observations can be predicted analytically by extending the single-photon wave-function model. Lastly, elongating a cloud along the line of laser propagation causes the excitation probability distribution to deviate from the exponential decay predicted by the Beer-Lambert law to the extent where the atoms at the back of the cloud are more excited than the atoms at the front. These calculations are conducted at the low densities relevant to recent experiments.
STORMVEX: The Storm Peak Lab Cloud Property Validation Experiment Science and Operations Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mace, J; Matrosov, S; Shupe, M
2010-09-29
During the Storm Peak Lab Cloud Property Validation Experiment (STORMVEX), a substantial correlative data set of remote sensing observations and direct in situ measurements from fixed and airborne platforms will be created in a winter season, mountainous environment. This will be accomplished by combining mountaintop observations at Storm Peak Laboratory and the airborne National Science Foundation-supported Colorado Airborne Multi-Phase Cloud Study campaign with collocated measurements from the second ARM Mobile Facility (AMF2). We describe in this document the operational plans and motivating science for this experiment, which includes deployment of AMF2 to Steamboat Springs, Colorado. The intensive STORMVEX field phasemore » will begin nominally on 1 November 2010 and extend to approximately early April 2011.« less
Interactions between spacecraft motions and the atmospheric cloud physics laboratory experiments
NASA Technical Reports Server (NTRS)
Anderson, B. J.
1981-01-01
In evaluating the effects of spacecraft motions on atmospheric cloud physics laboratory (ACPL) experimentation, the motions of concern are those which will result in the movement of the fluid or cloud particles within the experiment chambers. Of the various vehicle motions and residual forces which can and will occur, three types appear most likely to damage the experimental results: non-steady rotations through a large angle, long-duration accelerations in a constant direction, and vibrations. During the ACPL ice crystal growth experiments, the crystals are suspended near the end of a long fiber (20 cm long by 200 micron diameter) of glass or similar material. Small vibrations of the supported end of the fiber could cause extensive motions of the ice crystal, if care is not taken to avoid this problem.
Results of a simulator test comparing two display concepts for piloted flight-path-angle control
NASA Technical Reports Server (NTRS)
Kelley, W. W.
1978-01-01
Results of a simulator experiment which was conducted in order to compare pilot gamma-control performance using two display formats are reported. Pilots flew a variable flight path angle tracking task in the landing configuration. Pilot and airplane performance parameters were recorded and pilot comments noted for each case.
Contrasting Cloud Composition Between Coupled and Decoupled Marine Boundary Layer Clouds
NASA Astrophysics Data System (ADS)
WANG, Z.; Mora, M.; Dadashazar, H.; MacDonald, A.; Crosbie, E.; Bates, K. H.; Coggon, M. M.; Craven, J. S.; Xian, P.; Campbell, J. R.; AzadiAghdam, M.; Woods, R. K.; Jonsson, H.; Flagan, R. C.; Seinfeld, J.; Sorooshian, A.
2016-12-01
Marine stratocumulus clouds often become decoupled from the vertical layer immediately above the ocean surface. This study contrasts cloud chemical composition between coupled and decoupled marine stratocumulus clouds. Cloud water and droplet residual particle composition were measured in clouds off the California coast during three airborne experiments in July-August of separate years (E-PEACE 2011, NiCE 2013, BOAS 2015). Decoupled clouds exhibited significantly lower overall mass concentrations in both cloud water and droplet residual particles, consistent with reduced cloud droplet number concentration and sub-cloud aerosol (Dp > 100 nm) number concentration, owing to detachment from surface sources. Non-refractory sub-micrometer aerosol measurements show that coupled clouds exhibit higher sulfate mass fractions in droplet residual particles, owing to more abundant precursor emissions from the ocean and ships. Consequently, decoupled clouds exhibited higher mass fractions of organics, nitrate, and ammonium in droplet residual particles, owing to effects of long-range transport from more distant sources. Total cloud water mass concentration in coupled clouds was dominated by sodium and chloride, and their mass fractions and concentrations exceeded those in decoupled clouds. Conversely, with the exception of sea salt constituents (e.g., Cl, Na, Mg, K), cloud water mass fractions of all species examined were higher in decoupled clouds relative to coupled clouds. These results suggest that an important variable is the extent to which clouds are coupled to the surface layer when interpreting microphysical data relevant to clouds and aerosol particles.
Comparison between SAGE II and ISCCP high-level clouds. 2: Locating clouds tops
NASA Technical Reports Server (NTRS)
Liao, Xiaohan; Rossow, William B.; Rind, David
1995-01-01
A comparison is made of the vertical distribution of high-level cloud tops derived from the Stratospheric Aerosol and Gas Experiment II (SAGE II) occultation measurements and from the International Satellite Cloud Climatology Project (ISCCP) for all Julys and Januarys in 1985 to 1990. The results suggest that ISCCP overestimates the pressure of high-level clouds by up to 50-150 mbar, particularly at low latitudes. This is caused by the frequent presence of clouds with diffuse tops (greater than 50% time when cloudy events are observed). The averaged vertical extent of the diffuse top is about 1.5 km. At midlatitudes where the SAGE II and ISCCP cloud top pressure agree best, clouds with distinct tops reach a maximum relative proportion of the total level cloud amount (about 30-40%), and diffuse-topped clouds are reduced to their minimum (30-40%). The ISCCP-defined cloud top pressure should be regarded not as the material physical height of the clouds but as the level which emits the same infrared radiance as observed. SAGE II and ISCCP cloud top pressures agree for clouds with distinct tops. There is also an indication that the cloud top pressures of optically thin clouds not overlying thicker clouds are poorly estimated by ISCCP at middle latitudes. The average vertical extent of these thin clouds is about 2.5 km.
NASA Technical Reports Server (NTRS)
Sarter, Nadine B.; Woods, David D.
1992-01-01
Results are presented of two studies on the potential effect of cockpit automation on the pilot's performance, which provide data on pilots' difficulties with understanding and operating one of the core systems of cockpit automation, the Flight Management System (FMS). The results of both studies indicate that, although pilots do become proficient in standard FMS operations through ground training and subsequent flight experience, they still have difficulties tracking the FMS status and behavior in certain flight contexts and show gaps in the understanding of the functional structure of the system. The results suggest that design-related factors such as opaque interfaces contribute to these difficulties, which can affect the pilot's situation awareness.
Effect of time span and task load on pilot mental workload
NASA Technical Reports Server (NTRS)
Berg, S. L.; Sheridan, T. B.
1985-01-01
Two sets of experiments were run to examine how the mental workload of a pilot might be measured. The effects of continuous manual control activity versus discrete assigned mental tasks (including the length of time between receiving an assignment and executing it) were examined. The first experiment evaluated the strengths and weaknesses of measuring mental workload with an objective perforamance (altitude deviations) and five subjective ratings (activity level, complexity, difficulty, stress, and workload). The second set of experiments built upon the first set by increasing workload intensities and adding another performance measure: airspeed deviation. The results are discussed for both low and high experience pilots.
Field measurements of cloud droplet dynamics
NASA Astrophysics Data System (ADS)
Molacek, Jan; Bagheri, Gholamhossein; Bertens, Augustinus; Xu, Haitao; Bodenschatz, Eberhard
2017-11-01
We present an in-situ experiment investigating the dynamics of cloud droplets and its dependence on the turbulent flow properties. This dynamics plays a major role in the rate of growth of cloud particles by coalescence and the resulting precipitation rate. The experiment takes place at a mountain research station at an altitude of 2650m, and will make use of a movable platform that can travel with the mean wind velocity. Here we present preliminary results using a stationary setup. Simultaneous measurements of other variables such as droplet size distribution and humidity fluctuations are done in order to develop a more complete picture of the microphysical conditions within clouds. We thank the Bavarian State Ministry of the Environment and Consumer Protection for their generous financial support. We also acknowledge funding from European Union Horizon 2020 Programme via the COMPLETE project.
CRYSTAL: The Cirrus Regional Study of Tropical Anvils and Layers
NASA Technical Reports Server (NTRS)
Delnore, Victor E.; Cox, Stephen K.; Curran, Robert J.
1999-01-01
CRYSTAL the Cirrus Regional Study of Tropical Anvils and Layers is part of the ongoing series of field experiments to study clouds and their impact on world weather and climate, and will attempt to improve the application of cloud effects in global climate models. CRYSTAL is being planned as two parts: a limited CRYSTAL field campaign in 2001 to examine towering clouds and anvil genesis over the Everglades of Florida, and the main CRYSTAL field campaign in the summer of 2003 in the Tropical Western Pacific. The latter is timed to take advantage of several cloud measurement satellites that will be operational at that time. This paper discusses some of the issues to be addressed in CRYSTAL, gives a brief description of the research plan, and describes its relationship to other important field experiments.
Influence of roughness bottom on the dynamics of a buoyant cloud : application to a powder avalanche
NASA Astrophysics Data System (ADS)
Brossard, D.; Naaim-Bouvet, F.; Naaim, M.; Caccamo, P.
2009-04-01
A powder avalanche is referred to as a turbulent flow of snow particles in air. In the past such avalanches have been modelled by buoyant cloud in a watertank: buoyant clouds flow along an inclined plane from a small immersed tank with a release gate (injection is of short duration). The powder avalanches are simulated by a heavy fluid (salt water + colorant or kaolin) which is dispersing in a lighter one. Such experiments allow studies for the influence of roughness bottoms on the dynamics of a buoyant clouds. The authors studied the flows of buoyant clouds on an uniform slope of 20° with different roughness: smooth PVC, abrasive paper, bottom covered with glued particles of PMMA or with glued glass beads of different sizes arranged in a compact way. The released volume varies between 2 to 4 liters and the density of salted water is 1.2. Two cameras are used to obtain the height together with the front velocity. Inside the study area the front velocity is approximately constant and the height of the clouds varies linearly with the distance from the released gate as usually observed in previous experiments. So for each roughness a front velocity and height growth can be defined. It was shown from the experiments that: As the bottom increases in roughness, the front speed increases and the height growth decreases. Nevertheless the height of glued elements does not seem to be the most appropriate parameter to characterize the roughness.
NASA Technical Reports Server (NTRS)
Katz, U.
1982-01-01
Methods of particle generation and characterization with regard to their applicability for experiments requiring cloud condensation nuclei (CCN) of specified properties were investigated. Since aerosol characterization is a prerequisite to assessing performance of particle generation equipment, techniques for characterizing aerosol were evaluated. Aerosol generation is discussed, and atomizer and photolytic generators including preparation of hydrosols (used with atomizers) and the evaluation of a flight version of an atomizer are studied.
NASA Technical Reports Server (NTRS)
Whitlock, Charles H.; T R. acraitch, Eric J.
1987-01-01
A map, concise tables, and satellite images are presented which show ground-site locations, GOES visible/infrared instrument counts above each site, and cloud spatial distribution for the experiment region from 11 October through 2 November 1986. The cloud images are presented near times of the afternoon NOAA-9 satellite overpasses in order to provide a qualitative aid in the interpretation of TOVS, AVHRR, and heat budget data during the FIRE/SRB experiment.
A Comparison of Climate Feedback Strength between CO2 Doubling and LGM Experiments
NASA Astrophysics Data System (ADS)
Yoshimori, M.; Yokohata, T.; Abe-Ouchi, A.
2008-12-01
Studies of past climate potentially provide a constraint on the uncertainty of climate sensitivity, but previous studies warn against a simple scaling to the future. The climate sensitivity is determined by various feedback processes and they may vary with climate states and forcings. In this study, we investigate similarities and differences of feedbacks for a CO2 doubling, a last glacial maximum (LGM), and LGM greenhouse gas (GHG) forcing experiments, using an atmospheric general circulation model coupled to a slab ocean model. After computing the radiative forcing, the individual feedback strengths: water vapor, lapse rate, albedo, and cloud feedbacks, are evaluated explicitly. For this particular model, the difference in the climate sensitivity among experiments is attributed to the shortwave cloud feedback in which there is a tendency that it becomes weaker or even negative in the cooling experiments. No significant difference is found in the water vapor feedback between warming and cooling experiments by GHGs despite the nonlinear dependence of the Clausius-Clapeyron relation on temperature. The weaker water vapor feedback in the LGM experiment due to a relatively weaker tropical forcing is compensated by the stronger lapse rate feedback due to a relatively stronger extratropical forcing. A hypothesis is proposed which explains the asymmetric cloud response between warming and cooling experiments associated with a displacement of the region of mixed- phase clouds. The difference in the total feedback strength between experiments is, however, relatively small compared to the current intermodel spread, and does not necessarily preclude the use of LGM climate as a future constraint.
NASA Astrophysics Data System (ADS)
Kniffka, Anke; Knippertz, Peter; Fink, Andreas
2017-04-01
This contribution presents first results of numerical sensitivity experiments that are carried out in the framework of the project DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa). DACCIWA aims to investigate the impact of the drastic increase in anthropogenic emissions in West Africa on the local weather and climate, for example through cloud-aerosol interactions or impacts on radiation and stability. DACCIWA organised a major international field campaign in West Africa in June-July 2016 and involves a wide range of modelling activities. Several studies have shown - and first results of the DACCIWA campaign confirm - that extensive ultra-low stratus clouds form in the southern parts of West Africa (8°W-8°E, 5-10°N) at night in connection with strong nocturnal low-level jets. The clouds persist long after sunrise and have therefore a substantial impact on the surface radiation budget and consequently on the diurnal evolution of the daytime, convectively mixed boundary layer. The objective of this study is to investigate the sensitivity of the West African monsoon system and its diurnal cycle to the radiative effects of these low clouds. The study is based on a series of daily 5-day sensitivity simulations using ICON, the operational numerical weather prediction model of the German Weather Service during the months July - September 2006. In these simulations, low clouds are made transparent, by artificially lowering the optical thickness information passed on to the model's radiation scheme. Results reveal a noticeable influence of the low-level cloud cover on the atmospheric mean state of our region of interest and beyond. Also the diurnal development of the convective boundary layer is influenced by the cloud modification. In the transparent-cloud experiments, the cloud deck tends to break up later in the day and is shifted to a higher altitude, thereby causing a short-lived intensification around 11 LT. The average rainfall patterns are modified as well, though no conclusion on the long-term impact on rainfall can be made due to the forced initial conditions in the presented experiment. In the future, the impact on the development of the West African monsoon system will be assessed.
The Wisconsin Snow and Cloud-Terra 2000 Experiment (WISC-T2000)
NASA Technical Reports Server (NTRS)
2002-01-01
Atmospheric scientists take to the skies this winter for the Wisconsin Snow and Cloud-Terra 2000 experiment, Feb. 25 through March 13. Scientists in WISC-T2000 will use instruments on board NASA's ER-2, a high-altitude research plane, to validate new science products from NASA's earth-observing satellite Terra, which began its five-year mission on Dec. 18, 1999. Contact Terri Gregory Public Information Coordinator Space Science and Engineering Center University of Wisconsin-Madison (608) 263-3373; fax (608) 262-5974 terri.gregory@ssec.wisc.edu Science Goals: WISC-T2000 is the third in a series of field experiments sponsored by the University of Wisconsin-Madison's Space Science and Engineering Center. The center helped develop one of the five science instruments on Terra, the Moderate-Resolution Imaging Spectroradiometer (MODIS). MODIS will make global measurements of clouds, oceans, land, and atmospheric properties in an effort to monitor and predict global climate change. Infrastructure: The ER-2 will be based at Madison's Truax Field and will fly over the upper Midwest and Oklahoma. ER-2 measurements will be coordinated with observations at the Department of Energy's Cloud and Radiation Testbed site in Oklahoma (http://www.arm.gov/), which will be engaged in a complementary cloud experiment. The center will work closely with NASA's Goddard Space Flight Center, which will collect and distribute MODIS data and science products. Additional information on the WISC-T2000 field campaign is available at the project's Web site http://cimss.ssec.wisc.edu/wisct2000/
The first observed cloud echoes and microphysical parameter retrievals by China's 94-GHz cloud radar
NASA Astrophysics Data System (ADS)
Wu, Juxiu; Wei, Ming; Hang, Xin; Zhou, Jie; Zhang, Peichang; Li, Nan
2014-06-01
By using the cloud echoes first successfully observed by China's indigenous 94-GHz SKY cloud radar, the macrostructure and microphysical properties of drizzling stratocumulus clouds in Anhui Province on 8 June 2013 are analyzed, and the detection capability of this cloud radar is discussed. The results are as follows. (1) The cloud radar is able to observe the time-varying macroscopic and microphysical parameters of clouds, and it can reveal the microscopic structure and small-scale changes of clouds. (2) The velocity spectral width of cloud droplets is small, but the spectral width of the cloud containing both cloud droplets and drizzle is large. When the spectral width is more than 0.4 m s-1, the radar reflectivity factor is larger (over -10 dBZ). (3) The radar's sensitivity is comparatively higher because the minimum radar reflectivity factor is about -35 dBZ in this experiment, which exceeds the threshold for detecting the linear depolarized ratio (LDR) of stratocumulus (commonly -11 to -14 dBZ; decreases with increasing turbulence). (4) After distinguishing of cloud droplets from drizzle, cloud liquid water content and particle effective radius are retrieved. The liquid water content of drizzle is lower than that of cloud droplets at the same radar reflectivity factor.
ERIC Educational Resources Information Center
Pike, Ronald E.; Pittman, Jason M.; Hwang, Drew
2017-01-01
This paper investigates the use of a cloud computing environment to facilitate the teaching of web development at a university in the Southwestern United States. A between-subjects study of students in a web development course was conducted to assess the merits of a cloud computing environment instead of personal computers for developing websites.…
Cloud rise model for radiological dispersal devices events
NASA Astrophysics Data System (ADS)
Sharon, Avi; Halevy, Itzhak; Sattinger, Daniel; Yaar, Ilan
2012-07-01
As a part of the preparedness and response to possible radiological terror events, it is important to model the evolution of the radioactive cloud immediately after its formation, as a function of time, explosive quantity and local meteorological conditions. One of the major outputs of a cloud rise models is the evaluation of cloud top height, which is an essential input for most of the succeeding atmospheric dispersion models. This parameter strongly affects the radiological consequences of the event. Most of the cloud rise models used today, have been developed according to experiments were large quantities of explosives were used, within the range of hundreds of kilograms of TNT. The majority of these models, however, fail to address Radiological Dispersion Devices (RDD) events, which are typically characterized by smaller amounts of TNT. In this paper, a new, semi-empirical model that describes the vertical evolution of the cloud up to its effective height as a function of time, explosive quantity, atmospheric stability and horizontal wind speed, is presented. The database for this model is taken from five sets of experiments done in Israel during 2006-2009 under the "Green Field" (GF) project, using 0.25-100 kg of TNT.
NASA Technical Reports Server (NTRS)
Howard, James C.
1976-01-01
Remotely piloted research vehicles (RPRVS) are currently being flown from fixed-base control centers, and visual information is supplied to the remote pilot by a TV camera mounted in the vehicle. In these circumstances, the possibility of a TV failure or an interruption in the downlink to the pilot must be considered. To determine the influence of loss of TV information on pilot performance during the final approach and landing phase of a mission, an experiment was conducted in which pilots were asked to fly a fixed-base simulation of a Piper PA-30 aircraft with loss of TV information occurring at altitudes of 15.24, 30.48, and 45.72 m (50, 100, and 150 ft). For this experiment, a specially designed display configuration was presented to four pilots in accordance with a Latin square design. Initial results indicate that pilots could not ensure successful landings from altitudes exceeding 15.24 m (.50 ft) without the visual cues supplied by the TV picture.
Why undertake a pilot in a qualitative PhD study? Lessons learned to promote success.
Wray, Jane; Archibong, Uduak; Walton, Sean
2017-01-23
Background Pilot studies can play an important role in qualitative studies. Methodological and practical issues can be shaped and refined by undertaking pilots. Personal development and researchers' competence are enhanced and lessons learned can inform the development and quality of the main study. However, pilot studies are rarely published, despite their potential to improve knowledge and understanding of the research. Aim To present the main lessons learned from undertaking a pilot in a qualitative PhD study. Discussion This paper draws together lessons learned when undertaking a pilot as part of a qualitative research project. Important methodological and practical issues identified during the pilot study are discussed including access, recruitment, data collection and the personal development of the researcher. The resulting changes to the final study are also highlighted. Conclusion Sharing experiences of and lessons learned in a pilot study enhances personal development, improves researchers' confidence and competence, and contributes to the understanding of research. Implications for practice Pilots can be used effectively in qualitative studies to refine the final design, and provide the researcher with practical experience to enhance confidence and competence.
Profiling of Atmospheric Water Vapor from the SSM/T-2 Radiometric Measurements
NASA Technical Reports Server (NTRS)
Wang, J. R.
2000-01-01
An advantage of using the millimeter-wave measurements for water vapor profiling is the ability to probe beyond a moderate cloud cover. Such a capability has been demonstrated from an airborne MIR (Millimeter-wave Imaging Radiometer) flight over the Pacific Ocean during an intense observation period of TOGA/COARE (Tropical Ocean Global Atmosphere/ Couple Ocean Atmospheric Response Experiment) in early 1993. A Cloud Lidar System (CLS) and MODIS Airborne Simulator (MAS) were on board the same aircraft to identify the presence of clouds and cloud type. The retrieval algorithm not only provides output of a water vapor profile, but also the cloud liquid water and approximate cloud altitude required to satisfy convergence of the retrieval. The validity of these cloud parameters has not been verified previously. In this document, these cloud parameters are compared with those derived from concurrent measurements from the CLS and AMPR (Advanced Microwave Precipitation Radiometer).
Impact of cloud radiative heating on East Asian summer monsoon circulation
Guo, Zhun; Zhou, Tianjun; Wang, Minghuai; ...
2015-07-17
The impacts of cloud radiative heating on East Asian Summer Monsoon (EASM) over the southeastern China (105°-125°E, 20°-35°N) are explained by using the Community Atmosphere Model version 5 (CAM5). Sensitivity experiments demonstrate that the radiative heating of clouds leads to a positive effect on the local EASM circulation over southeastern China. Without the radiative heating of cloud, the EASM circulation and precipitation would be much weaker than that in the normal condition. The longwave heating of clouds dominates the changes of EASM circulation. The positive effect of clouds on EASM circulation is explained by the thermodynamic energy equation, i.e. themore » different heating rate between cloud base and cloud top enhances the convective instability over southeastern China, which enhances updraft consequently. The strong updraft would further result in a southward meridional wind above the center of the updraft through Sverdrup vorticity balance.« less
A Review Study on Cloud Computing Issues
NASA Astrophysics Data System (ADS)
Kanaan Kadhim, Qusay; Yusof, Robiah; Sadeq Mahdi, Hamid; Al-shami, Sayed Samer Ali; Rahayu Selamat, Siti
2018-05-01
Cloud computing is the most promising current implementation of utility computing in the business world, because it provides some key features over classic utility computing, such as elasticity to allow clients dynamically scale-up and scale-down the resources in execution time. Nevertheless, cloud computing is still in its premature stage and experiences lack of standardization. The security issues are the main challenges to cloud computing adoption. Thus, critical industries such as government organizations (ministries) are reluctant to trust cloud computing due to the fear of losing their sensitive data, as it resides on the cloud with no knowledge of data location and lack of transparency of Cloud Service Providers (CSPs) mechanisms used to secure their data and applications which have created a barrier against adopting this agile computing paradigm. This study aims to review and classify the issues that surround the implementation of cloud computing which a hot area that needs to be addressed by future research.
Climatological Data for Clouds Over the Globe from Surface Observations (1988) (NDP-026)
Hahn, Carole J. [Univ. of Colorado, Boulder, CO (United States). Cooperative Inst. for Research in Environmental Sciences (CIRES); Warren, Stephen G. [Department of Atmospheric Sciences, University of Washington, Seattle, Washington; London, Julius [Department of Astrophysical, Planetary, and Atmospheric Sciences, University of Colorado, Boulder, CO; Jenne, Ray L. [National Center for Atmospheric Research, Boulder, CO (United States); Chervin, Robert M. [National Center for Atmospheric Research, Boulder, CO (United States)
1988-01-01
With some data from as early as 1930, global long-term monthly and/or seasonal total cloud cover, cloud type amounts and frequencies of occurrence, low cloud base heights, harmonic analyses of annual and diurnal cycles, interannual variations and trends, and cloud type co-occurrences have been compiled and presented in two atlases (Warren et al. 1988, 1990). These data were derived from land and ship synoptic weather reports from the "SPOT" archive of the Fleet Numerical Oceanography Center (FNOC) and from Release 1 of the Comprehensive Ocean-Atmosphere Data Set (COADS) for the years 1930-1979. The data are in 12 files (one containing latitude, longitude, land-fraction, and number of land stations for grid boxes; four containing total cloud, cloud types, harmonic analyses, and interannual variations and trends for land; four containing total cloud, cloud types, harmonic analyses, and interannual variations and trends for oceans; one containing first cloud analyses for the first year of the GARP Global Experiment (FGGE); one containing cloud-type co-occurrences for land and oceans; and one containing a FORTRAN program to read and produce maps).
NASA Astrophysics Data System (ADS)
Jensen, M. P.; Miller, M. A.; Wang, J.
2017-12-01
The first Intensive Observation Period of the DOE Aerosol and Cloud Experiments in the Eastern North Atlantic (ACE-ENA) took place from 21 June through 20 July 2017 involving the deployment of the ARM Gulfstream-159 (G-1) aircraft with a suite of in situ cloud and aerosol instrumentation in the vicinity of the ARM Climate Research Facility Eastern North Atlantic (ENA) site on Graciosa Island, Azores. Here we present preliminary analysis of the thermodynamic characteristics of the marine boundary layer and the variability of cloud properties for a mixed cloud field including both stratiform cloud layers and deeper cumulus elements. Analysis combines in situ atmospheric state observations from the G-1 with radiosonde profiles and surface meteorology from the ENA site in order to characterize the thermodynamic structure of the marine boundary layer including the coupling state and stability. Cloud/drizzle droplet size distributions measured in situ are combined with remote sensing observations from a scanning cloud radar, and vertically pointing cloud radar and lidar provide quantification of the macrophysical and microphysical properties of the mixed cloud field.
NASA Astrophysics Data System (ADS)
Chee, T.; Nguyen, L.; Smith, W. L., Jr.; Spangenberg, D.; Palikonda, R.; Bedka, K. M.; Minnis, P.; Thieman, M. M.; Nordeen, M.
2017-12-01
Providing public access to research products including cloud macro and microphysical properties and satellite imagery are a key concern for the NASA Langley Research Center Cloud and Radiation Group. This work describes a web based visualization tool and API that allows end users to easily create customized cloud product and satellite imagery, ground site data and satellite ground track information that is generated dynamically. The tool has two uses, one to visualize the dynamically created imagery and the other to provide access to the dynamically generated imagery directly at a later time. Internally, we leverage our practical experience with large, scalable application practices to develop a system that has the largest potential for scalability as well as the ability to be deployed on the cloud to accommodate scalability issues. We build upon NASA Langley Cloud and Radiation Group's experience with making real-time and historical satellite cloud product information, satellite imagery, ground site data and satellite track information accessible and easily searchable. This tool is the culmination of our prior experience with dynamic imagery generation and provides a way to build a "mash-up" of dynamically generated imagery and related kinds of information that are visualized together to add value to disparate but related information. In support of NASA strategic goals, our group aims to make as much scientific knowledge, observations and products available to the citizen science, research and interested communities as well as for automated systems to acquire the same information for data mining or other analytic purposes. This tool and the underlying API's provide a valuable research tool to a wide audience both as a standalone research tool and also as an easily accessed data source that can easily be mined or used with existing tools.
A cloudiness transition in a marine boundary layer
NASA Technical Reports Server (NTRS)
Betts, Alan K.; Boers, Reinout
1990-01-01
Boundary layer cloudiness plays several important roles in the energy budget of the earth. Low level stratocumulus are highly reflective clouds which reduce the net incoming shortwave radiation at the earth's surface. Climatically, the transition to a small area fraction of scattered cumulus clouds occurs as the air flows over warmer water. Although these clouds reflect less sunlight, they still play an important role in the boundary layer equilibrium by transporting water vapor upwards, and enhancing the surface evaporation. The First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE) included a marine stratocumulus experiment off the southern California coast from June 29 to July 19, 1987. The objectives of this experiment were to study the controls on fractional cloudiness, and to assess the role of cloud-top entrainment instability (CTEI) and mesoscale structure in determining cloud type. The focus is one research day, July 7, 1987, when coordinated aircraft missions were flown by four research aircraft, centered on a LANDSAT scene at 1830 UTC. The remarkable feature of this LANDSAT scene is the transition from a clear sky in the west through broken cumulus to solid stratocumulus in the east. The dynamic and thermodynamic structure of this transition in cloudiness is analyzed using data from the NCAR Electra. By averaging the aircraft data, the internal structure of the different cloud regimes is documented, and it is shown that the transition between broken cumulus and stratocumulus is associated with a change in structure with respect to the CTEI condition. However, this results not from sea surface temperature changes, but mostly from a transition in the air above the inversion, and the breakup appears to be at a structure on the unstable side of the wet virtual adiabat.
Inflight - Apollo 9 (Crew Activities)
1969-03-06
S69-26150 (6 March 1969) --- Television watchers on Earth saw this view of the Apollo 9 Command Module during the second live telecast from Apollo 9 early Thursday afternoon on the fourth day in space. This view is looking through the docking window of the Lunar Module. The cloud-covered Earth can be seen in the background. Inside the Lunar Module "Spider" were Astronauts James A. McDivitt, Apollo 9 commander; and Russell L. Schweickart, lunar module pilot. At this moment Apollo 9 was orbiting Earth with the Command and Service Modules docked nose-to-nose with the Lunar Module. Astronaut David R. Scott, command module pilot, remained at the controls in the Command Module "Gumdrop" while the other two astronauts checked out the Lunar Module. McDivitt and Schweickart moved into the Lunar Module from the Command Module by way of the docking tunnel.
Seasonal and Vegetational Variation in Albedo Measured During CERES Ground-Validation Pilot Study
NASA Technical Reports Server (NTRS)
Schuster, G. L.; Whitlock, C. H.; Plant, J. V.; Wheeler, R. J.; Moats, C. D.; Larman, K. T.; Ayers, J. K.; Feldl, E. K.
1997-01-01
The Clouds and the Earth's Radiant Energy System (CERES) satellite is scheduled for launch in the Fall of 1997 aboard the Tropical Rainfall Measuring Mission (TRMM). A surface measurement pilot study has been initiated in a 37-km region near Richmond, VA, for comparison with the CERES surface flux retrievals. Two-minute averaged upwelling and downwelling surface fluxes over a mostly deciduous forest have been recorded daily for the past two years, and show a broadband, shortwave daily albedo increase during the summer months. Evidence is presented that indicates vegetational changes in the forest as the overriding mechanism for this change. Upwelling flux measured over the entire region by helicopter-mounted instrumentation has been processed for four solar seasons. Future plans include the installation of four more albedo surface sites over various types of vegetation throughout the region.
ARM/GCSS/SPARC TWP-ICE CRM Intercomparison Study
NASA Technical Reports Server (NTRS)
Fridlind, Ann; Ackerman, Andrew; Petch, Jon; Field, Paul; Hill, Adrian; McFarquhar, Greg; Xie, Shaocheng; Zhang, Minghua
2010-01-01
Specifications are provided for running a cloud-resolving model (CRM) and submitting results in a standardized format for inclusion in a n intercomparison study and archiving for public access. The simulated case study is based on measurements obtained during the 2006 Tropical Warm Pool - International Cloud Experiment (TWP-ICE) led by the U. S. department of Energy Atmospheric Radiation Measurement (ARM) program. The modeling intercomparison study is based on objectives developed in concert with the Stratospheric Processes And their Role in Climate (SPARC) program and the GEWEX cloud system study (GCSS) program. The Global Energy and Water Cycle Experiment (GEWEX) is a core project of the World Climate Research PRogramme (WCRP).
NASA Astrophysics Data System (ADS)
Kalesse, H.; Myagkov, A.; Seifert, P.; Buehl, J.
2015-12-01
Cloud radar Doppler spectra offer much information about cloud processes. By analyzing millimeter radar Doppler spectra from cloud-top to -base in mixed-phase clouds in which super-cooled liquid-layers are present we try to tell the microphysical evolution story of particles that are present by disentangling the contributions of the solid and liquid particles to the total radar returns. Instead of considering vertical profiles, dynamical effects are taken into account by following the particle population evolution along slanted paths which are caused by horizontal advection of the cloud. The goal is to identify regions in which different microphysical processes such as new particle formation (nucleation), water vapor deposition, aggregation, riming, or sublimation occurr. Cloud radar measurements are supplemented by Doppler lidar and Raman lidar observations as well as observations with MWR, wind profiler, and radio sondes. The presence of super-cooled liquid layers is identified by positive liquid water paths in MWR measurements, the vertical location of liquid layers (in non-raining systems and below lidar extinction) is derived from regions of high-backscatter and low depolarization in Raman lidar observations. In collocated cloud radar measurements, we try to identify cloud phase in the cloud radar Doppler spectrum via location of the Doppler peak(s), the existence of multi-modalities or the spectral skewness. Additionally, within the super-cooled liquid layers, the radar-identified liquid droplets are used as air motion tracer to correct the radar Doppler spectrum for vertical air motion w. These radar-derived estimates of w are validated by independent estimates of w from collocated Doppler lidar measurements. A 35 GHz vertically pointing cloud Doppler radar (METEK MIRA-35) in linear depolarization (LDR) mode is used. Data is from the deployment of the Leipzig Aerosol and Cloud Remote Observations System (LACROS) during the Analysis of the Composition of Clouds with Extended Polarization Techniques (ACCEPT) field experiment in Cabauw, Netherlands in Fall 2014. There, another MIRA-35 was operated in simultaneous transmission and simultaneous reception (STSR) mode for obtaining measurements of differential reflectivity (ZDR) and correlation coefficient ρhv.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morrison, H.; Zuidema, Paquita; Ackerman, Andrew
2011-06-16
An intercomparison of six cloud-resolving and large-eddy simulation models is presented. This case study is based on observations of a persistent mixed-phase boundary layer cloud gathered on 7 May, 1998 from the Surface Heat Budget of Arctic Ocean (SHEBA) and First ISCCP Regional Experiment - Arctic Cloud Experiment (FIRE-ACE). Ice nucleation is constrained in the simulations in a way that holds the ice crystal concentration approximately fixed, with two sets of sensitivity runs in addition to the baseline simulations utilizing different specified ice nucleus (IN) concentrations. All of the baseline and sensitivity simulations group into two distinct quasi-steady states associatedmore » with either persistent mixed-phase clouds or all-ice clouds after the first few hours of integration, implying the existence of multiple equilibria. These two states are associated with distinctly different microphysical, thermodynamic, and radiative characteristics. Most but not all of the models produce a persistent mixed-phase cloud qualitatively similar to observations using the baseline IN/crystal concentration, while small increases in the IN/crystal concentration generally lead to rapid glaciation and conversion to the all-ice state. Budget analysis indicates that larger ice deposition rates associated with increased IN/crystal concentrations have a limited direct impact on dissipation of liquid in these simulations. However, the impact of increased ice deposition is greatly enhanced by several interaction pathways that lead to an increased surface precipitation flux, weaker cloud top radiative cooling and cloud dynamics, and reduced vertical mixing, promoting rapid glaciation of the mixed-phase cloud for deposition rates in the cloud layer greater than about 1-2x10-5 g kg-1 s-1. These results indicate the critical importance of precipitation-radiative-dynamical interactions in simulating cloud phase, which have been neglected in previous fixed-dynamical parcel studies of the cloud phase parameter space. Large sensitivity to the IN/crystal concentration also suggests the need for improved understanding of ice nucleation and its parameterization in models.« less
Adaptive Controller Effects on Pilot Behavior
NASA Technical Reports Server (NTRS)
Trujillo, Anna C.; Gregory, Irene M.; Hempley, Lucas E.
2014-01-01
Adaptive control provides robustness and resilience for highly uncertain, and potentially unpredictable, flight dynamics characteristic. Some of the recent flight experiences of pilot-in-the-loop with an adaptive controller have exhibited unpredicted interactions. In retrospect, this is not surprising once it is realized that there are now two adaptive controllers interacting, the software adaptive control system and the pilot. An experiment was conducted to categorize these interactions on the pilot with an adaptive controller during control surface failures. One of the objectives of this experiment was to determine how the adaptation time of the controller affects pilots. The pitch and roll errors, and stick input increased for increasing adaptation time and during the segment when the adaptive controller was adapting. Not surprisingly, altitude, cross track and angle deviations, and vertical velocity also increase during the failure and then slowly return to pre-failure levels. Subjects may change their behavior even as an adaptive controller is adapting with additional stick inputs. Therefore, the adaptive controller should adapt as fast as possible to minimize flight track errors. This will minimize undesirable interactions between the pilot and the adaptive controller and maintain maneuvering precision.
14 CFR 61.159 - Aeronautical experience: Airplane category rating.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aeronautical experience: Airplane category... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a pilot...
14 CFR 61.159 - Aeronautical experience: Airplane category rating.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aeronautical experience: Airplane category... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a pilot...
14 CFR 61.159 - Aeronautical experience: Airplane category rating.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aeronautical experience: Airplane category... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a pilot...
14 CFR 61.159 - Aeronautical experience: Airplane category rating.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Aeronautical experience: Airplane category... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a pilot...
14 CFR 61.159 - Aeronautical experience: Airplane category rating.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical experience: Airplane category... Transport Pilots § 61.159 Aeronautical experience: Airplane category rating. (a) Except as provided in... certificate with an airplane category and class rating must have at least 1,500 hours of total time as a pilot...
NASA Astrophysics Data System (ADS)
Zhou, Y.; Hou, A.; Lau, W. K.; Shie, C.; Tao, W.; Lin, X.; Chou, M.; Olson, W. S.; Grecu, M.
2006-05-01
The cloud and precipitation statistics simulated by 3D Goddard Cumulus Ensemble (GCE) model during the South China Sea Monsoon Experiment (SCSMEX) is compared with Tropical Rainfall Measuring Mission (TRMM) TMI and PR rainfall measurements and the Earth's Radiant Energy System (CERES) single scanner footprint (SSF) radiation and cloud retrievals. It is found that GCE is capable of simulating major convective system development and reproducing total surface rainfall amount as compared with rainfall estimated from the soundings. Mesoscale organization is adequately simulated except when environmental wind shear is very weak. The partitions between convective and stratiform rain are also close to TMI and PR classification. However, the model simulated rain spectrum is quite different from either TMI or PR measurements. The model produces more heavy rains and light rains (less than 0.1 mm/hr) than the observations. The model also produces heavier vertical hydrometer profiles of rain, graupel when compared with TMI retrievals and PR radar reflectivity. Comparing GCE simulated OLR and cloud properties with CERES measurements found that the model has much larger domain averaged OLR due to smaller total cloud fraction and a much skewed distribution of OLR and cloud top than CERES observations, indicating that the model's cloud field is not wide spread, consistent with the model's precipitation activity. These results will be used as guidance for improving the model's microphysics.
The analysis of the pilot's cognitive and decision processes
NASA Technical Reports Server (NTRS)
Curry, R. E.
1975-01-01
Articles are presented on pilot performance in zero-visibility precision approach, failure detection by pilots during automatic landing, experiments in pilot decision-making during simulated low visibility approaches, a multinomial maximum likelihood program, and a random search algorithm for laboratory computers. Other topics discussed include detection of system failures in multi-axis tasks and changes in pilot workload during an instrument landing.
HOPE: An On-Line Piloted Handling Qualities Experiment Data Book
NASA Technical Reports Server (NTRS)
Jackson, E. B.; Proffitt, Melissa S.
2010-01-01
A novel on-line database for capturing most of the information obtained during piloted handling qualities experiments (either flight or simulated) is described. The Hyperlinked Overview of Piloted Evaluations (HOPE) web application is based on an open-source object-oriented Web-based front end (Ruby-on-Rails) that can be used with a variety of back-end relational database engines. The hyperlinked, on-line data book approach allows an easily-traversed way of looking at a variety of collected data, including pilot ratings, pilot information, vehicle and configuration characteristics, test maneuvers, and individual flight test cards and repeat runs. It allows for on-line retrieval of pilot comments, both audio and transcribed, as well as time history data retrieval and video playback. Pilot questionnaires are recorded as are pilot biographies. Simple statistics are calculated for each selected group of pilot ratings, allowing multiple ways to aggregate the data set (by pilot, by task, or by vehicle configuration, for example). Any number of per-run or per-task metrics can be captured in the database. The entire run metrics dataset can be downloaded in comma-separated text for further analysis off-line. It is expected that this tool will be made available upon request
Arctic Boreal Vulnerability Experiment (ABoVE) Science Cloud
NASA Astrophysics Data System (ADS)
Duffy, D.; Schnase, J. L.; McInerney, M.; Webster, W. P.; Sinno, S.; Thompson, J. H.; Griffith, P. C.; Hoy, E.; Carroll, M.
2014-12-01
The effects of climate change are being revealed at alarming rates in the Arctic and Boreal regions of the planet. NASA's Terrestrial Ecology Program has launched a major field campaign to study these effects over the next 5 to 8 years. The Arctic Boreal Vulnerability Experiment (ABoVE) will challenge scientists to take measurements in the field, study remote observations, and even run models to better understand the impacts of a rapidly changing climate for areas of Alaska and western Canada. The NASA Center for Climate Simulation (NCCS) at the Goddard Space Flight Center (GSFC) has partnered with the Terrestrial Ecology Program to create a science cloud designed for this field campaign - the ABoVE Science Cloud. The cloud combines traditional high performance computing with emerging technologies to create an environment specifically designed for large-scale climate analytics. The ABoVE Science Cloud utilizes (1) virtualized high-speed InfiniBand networks, (2) a combination of high-performance file systems and object storage, and (3) virtual system environments tailored for data intensive, science applications. At the center of the architecture is a large object storage environment, much like a traditional high-performance file system, that supports data proximal processing using technologies like MapReduce on a Hadoop Distributed File System (HDFS). Surrounding the storage is a cloud of high performance compute resources with many processing cores and large memory coupled to the storage through an InfiniBand network. Virtual systems can be tailored to a specific scientist and provisioned on the compute resources with extremely high-speed network connectivity to the storage and to other virtual systems. In this talk, we will present the architectural components of the science cloud and examples of how it is being used to meet the needs of the ABoVE campaign. In our experience, the science cloud approach significantly lowers the barriers and risks to organizations that require high performance computing solutions and provides the NCCS with the agility required to meet our customers' rapidly increasing and evolving requirements.
Terrain Portrayal for Head-Down Displays Experiment
NASA Technical Reports Server (NTRS)
Hughes, Monica F.; Takallu, M. A.
2002-01-01
The General Aviation Element of the Aviation Safety Program's Synthetic Vision Systems (SVS) Project is developing technology to eliminate low visibility induced General Aviation (GA) accidents. SVS displays present computer generated 3-dimensional imagery of the surrounding terrain on the Primary Flight Display (PFD) to greatly enhance pilot's situation awareness (SA), reducing or eliminating Controlled Flight into Terrain, as well as Low-Visibility Loss of Control accidents. SVS-conducted research is facilitating development of display concepts that provide the pilot with an unobstructed view of the outside terrain, regardless of weather conditions and time of day. A critical component of SVS displays is the appropriate presentation of terrain to the pilot. An experimental study has been conducted at NASA Langley Research Center (LaRC) to explore and quantify the relationship between the realism of the terrain presentation and resulting enhancements of pilot SA and pilot performance. Composed of complementary simulation and flight test efforts, Terrain Portrayal for Head-Down Displays (TP-HDD) experiments will help researchers evaluate critical terrain portrayal concepts. The experimental effort is to provide data to enable design trades that optimize SVS applications, as well as develop requirements and recommendations to facilitate the certification process. This paper focuses on the experimental set-up and preliminary qualitative results of the TP-HDD simulation experiment. In this experiment a fixed based flight simulator was equipped with various types of Head Down flight displays, ranging from conventional round dials (typical of most GA aircraft) to glass cockpit style PFD's. The variations of the PFD included an assortment of texturing and Digital Elevation Model (DEM) resolution combinations. A test matrix of 10 terrain display configurations (in addition to the baseline displays) were evaluated by 27 pilots of various backgrounds and experience levels. Qualitative (questionnaires) and quantitative (pilot performance and physiological) data were collected during the experimental runs. Preliminary results indicate that all of the evaluation pilots favored SVS displays over standard gauges, in terms of terrain awareness, SA, and perceived pilot performance. Among the terrain portrayal concepts tested, most pilots preferred the higher-resolution DEM. In addition, with minimal training, low-hour VFR evaluation pilots were able to negotiate a precision approach using SVS displays with a tunnel in the sky guidance concept.
Legal issues in clouds: towards a risk inventory.
Djemame, Karim; Barnitzke, Benno; Corrales, Marcelo; Kiran, Mariam; Jiang, Ming; Armstrong, Django; Forgó, Nikolaus; Nwankwo, Iheanyi
2013-01-28
Cloud computing technologies have reached a high level of development, yet a number of obstacles still exist that must be overcome before widespread commercial adoption can become a reality. In a cloud environment, end users requesting services and cloud providers negotiate service-level agreements (SLAs) that provide explicit statements of all expectations and obligations of the participants. If cloud computing is to experience widespread commercial adoption, then incorporating risk assessment techniques is essential during SLA negotiation and service operation. This article focuses on the legal issues surrounding risk assessment in cloud computing. Specifically, it analyses risk regarding data protection and security, and presents the requirements of an inherent risk inventory. The usefulness of such a risk inventory is described in the context of the OPTIMIS project.
The effect of clouds on the earth's radiation balance
NASA Technical Reports Server (NTRS)
Herman, G. F.; Wu, M. L. C.; Johnson, W. T.
1979-01-01
The effect of global cloudiness on the radiation balance at the top of the atmosphere is studied in general circulation model experiments. Wintertime simulations were conducted with clouds that had realistic optical properties, and were compared with simulations in which the clouds were transparent to either solar or thermal radiation. Clouds increase the net balance by limiting longwave loss to space, but decrease it by reflecting solar radiation. It is found that the net result of cloudiness is to maintain net radiation which is less than would be realized under clear conditions: Clouds cause the net radiation at the top of the atmosphere to increase due to longwave absorption, but to decrease even more due to cloud reflectance of solar radiation.
Alterations of Cloud Microphysics Due to Cloud Processed CCN
NASA Astrophysics Data System (ADS)
Hudson, J. G.; Tabor, S. S.; Noble, S. R., Jr.
2015-12-01
High-resolution CCN spectra have revealed bimodality (Hudson et al. 2015) similar to aerosol size spectra (e.g., Hoppel et al. 1985). Bimodality is caused by chemical and physical cloud processes that increase mass or hygroscopicity of only CCN that produced activated cloud droplets. Bimodality is categorized by relative CCN concentrations (NCCN) within the two modes, Nu-Np; i.e., NCCN within the higher critical supersaturation, Sc, mode that did not undergo cloud processing minus NCCN within the lower Sc mode that was cloud processed. Lower, especially negative, Nu-Np designates greater processing. The table shows regressions between Nu-Np and characteristics of clouds nearest the CCN measurements. ICE-T MASE parameter R SL R SL Nc 0.17 93.24 -0.26 98.65 MD -0.31 99.69 0.33 99.78 σ -0.27 99.04 0.48 100.00 Ld -0.31 99.61 0.38 99.96 Table. Correlation coefficients, R, and one-tailed significance levels in percent, SL, for Nu-Np with microphysics of the clouds closest to each CCN measurement, 75 ICE-T and 74 MASE cases. Nc is cloud droplet concentration, MD is cloud droplet mean diameter, σ is standard deviation of cloud droplet spectra, Ldis drizzle drop LWC. Two aircraft field campaigns, Ice in Clouds Experiment-Tropical (ICE-T) and Marine Stratus/Stratocumulus Experiment (MASE) show opposite R signs because coalescence dominated cloud processing in low altitude ICE-T cumuli whereas chemical transformations predominated in MASE low altitude polluted stratus. Coalescence reduces Nc and NCCN, which thus increases MD, and σ, which promote Ld. Chemical transformations, e.g., SO2 to SO4, increase CCN hygroscopicity, thus reducing Sc, but not affecting Nc or NCCN. Lower Sc CCN are capable of producing greater Nc in subsequent cloud cycles, which leads to lower MD and σ which reduce Ld (figure). These observations are consistent with cloud droplet growth models for the higher vertical wind (W) of cumuli and lower W of stratus. Coalescence thus reduces the indirect aerosol effect (IAE) with a positive feedback that further enhances coalescence and drizzle. Chemical cloud processing enhances both components of IAE; 1st IAE by greater droplet surface area, 2ndIAE by suppressing drizzle and thus increasing cloudiness. Hoppel, Fitzgerald and Larson: JGR 90, 2365-79 Hudson, Noble and Tabor: JGRA 120, 3436-52
Entrainment in Laboratory Simulations of Cumulus Cloud Flows
NASA Astrophysics Data System (ADS)
Narasimha, R.; Diwan, S.; Subrahmanyam, D.; Sreenivas, K. R.; Bhat, G. S.
2010-12-01
A variety of cumulus cloud flows, including congestus (both shallow bubble and tall tower types), mediocris and fractus have been generated in a water tank by simulating the release of latent heat in real clouds. The simulation is achieved through ohmic heating, injected volumetrically into the flow by applying suitable voltages between diametral cross-sections of starting jets and plumes of electrically conducting fluid (acidified water). Dynamical similarity between atmospheric and laboratory cloud flows is achieved by duplicating values of an appropriate non-dimensional heat release number. Velocity measurements, made by laser instrumentation, show that the Taylor entrainment coefficient generally increases just above the level of commencement of heat injection (corresponding to condensation level in the real cloud). Subsequently the coefficient reaches a maximum before declining to the very low values that characterize tall cumulus towers. The experiments also simulate the protected core of real clouds. Cumulus Congestus : Atmospheric cloud (left), simulated laboratory cloud (right). Panels below show respectively total heat injected and vertical profile of heating in the laboratory cloud.
The registration of non-cooperative moving targets laser point cloud in different view point
NASA Astrophysics Data System (ADS)
Wang, Shuai; Sun, Huayan; Guo, Huichao
2018-01-01
Non-cooperative moving target multi-view cloud registration is the key technology of 3D reconstruction of laser threedimension imaging. The main problem is that the density changes greatly and noise exists under different acquisition conditions of point cloud. In this paper, firstly, the feature descriptor is used to find the most similar point cloud, and then based on the registration algorithm of region segmentation, the geometric structure of the point is extracted by the geometric similarity between point and point, The point cloud is divided into regions based on spectral clustering, feature descriptors are created for each region, searching to find the most similar regions in the most similar point of view cloud, and then aligning the pair of point clouds by aligning their minimum bounding boxes. Repeat the above steps again until registration of all point clouds is completed. Experiments show that this method is insensitive to the density of point clouds and performs well on the noise of laser three-dimension imaging.
Strong Constraints on Aerosol-Cloud Interactions from Volcanic Eruptions
NASA Technical Reports Server (NTRS)
Malavelle, Florent F.; Haywood, Jim M.; Jones, Andy; Gettelman, Andrew; Clarisse, Lieven; Bauduin, Sophie; Allan, Richard P.; Karset, Inger Helene H.; Kristjansson, Jon Egill; Oreopoulos, Lazaros;
2017-01-01
Aerosols have a potentially large effect on climate, particularly through their interactions with clouds, but the magnitude of this effect is highly uncertain. Large volcanic eruptions produce sulfur dioxide, which in turn produces aerosols; these eruptions thus represent a natural experiment through which to quantify aerosol-cloud interactions. Here we show that the massive 2014-2015 fissure eruption in Holuhraun, Iceland, reduced the size of liquid cloud droplets - consistent with expectations - but had no discernible effect on other cloud properties. The reduction in droplet size led to cloud brightening and global-mean radiative forcing of around minus 0.2 watts per square metre for September to October 2014. Changes in cloud amount or cloud liquid water path, however, were undetectable, indicating that these indirect effects, and cloud systems in general, are well buffered against aerosol changes. This result will reduce uncertainties in future climate projections, because we are now able to reject results from climate models with an excessive liquid-water-path response.
Strong constraints on aerosol-cloud interactions from volcanic eruptions.
Malavelle, Florent F; Haywood, Jim M; Jones, Andy; Gettelman, Andrew; Clarisse, Lieven; Bauduin, Sophie; Allan, Richard P; Karset, Inger Helene H; Kristjánsson, Jón Egill; Oreopoulos, Lazaros; Cho, Nayeong; Lee, Dongmin; Bellouin, Nicolas; Boucher, Olivier; Grosvenor, Daniel P; Carslaw, Ken S; Dhomse, Sandip; Mann, Graham W; Schmidt, Anja; Coe, Hugh; Hartley, Margaret E; Dalvi, Mohit; Hill, Adrian A; Johnson, Ben T; Johnson, Colin E; Knight, Jeff R; O'Connor, Fiona M; Partridge, Daniel G; Stier, Philip; Myhre, Gunnar; Platnick, Steven; Stephens, Graeme L; Takahashi, Hanii; Thordarson, Thorvaldur
2017-06-22
Aerosols have a potentially large effect on climate, particularly through their interactions with clouds, but the magnitude of this effect is highly uncertain. Large volcanic eruptions produce sulfur dioxide, which in turn produces aerosols; these eruptions thus represent a natural experiment through which to quantify aerosol-cloud interactions. Here we show that the massive 2014-2015 fissure eruption in Holuhraun, Iceland, reduced the size of liquid cloud droplets-consistent with expectations-but had no discernible effect on other cloud properties. The reduction in droplet size led to cloud brightening and global-mean radiative forcing of around -0.2 watts per square metre for September to October 2014. Changes in cloud amount or cloud liquid water path, however, were undetectable, indicating that these indirect effects, and cloud systems in general, are well buffered against aerosol changes. This result will reduce uncertainties in future climate projections, because we are now able to reject results from climate models with an excessive liquid-water-path response.
a Global Registration Algorithm of the Single-Closed Ring Multi-Stations Point Cloud
NASA Astrophysics Data System (ADS)
Yang, R.; Pan, L.; Xiang, Z.; Zeng, H.
2018-04-01
Aimed at the global registration problem of the single-closed ring multi-stations point cloud, a formula in order to calculate the error of rotation matrix was constructed according to the definition of error. The global registration algorithm of multi-station point cloud was derived to minimize the error of rotation matrix. And fast-computing formulas of transformation matrix with whose implementation steps and simulation experiment scheme was given. Compared three different processing schemes of multi-station point cloud, the experimental results showed that the effectiveness of the new global registration method was verified, and it could effectively complete the global registration of point cloud.
The 1975 accident experience of civilian pilots with static physical defects.
DOT National Transportation Integrated Search
1977-08-01
The 1974 aircraft accident experience of civilian pilots with eight selected static physical defects has been examined and reported previously. Three categories--blindness or absence of either eye, deficient color vision with a waiver, and deficient ...
PROGRESS REPORT OF FY 2004 ACTIVITIES: IMPROVED WATER VAPOR AND CLOUD RETRIEVALS AT THE NSA/AAO
DOE Office of Scientific and Technical Information (OSTI.GOV)
E. R. Westwater; V. V. Leuskiy; M. Klein
2004-11-01
The basic goals of the research are to develop and test algorithms and deploy instruments that improve measurements of water vapor, cloud liquid, and cloud coverage, with a focus on the Arctic conditions of cold temperatures and low concentrations of water vapor. The importance of accurate measurements of column amounts of water vapor and cloud liquid has been well documented by scientists within the Atmospheric Radiation Measurement Program. Although several technologies have been investigated to measure these column amounts, microwave radiometers (MWR) have been used operationally by the ARM program for passive retrievals of these quantities: precipitable water vapor (PWV)more » and integrated water liquid (IWL). The technology of PWV and IWL retrievals has advanced steadily since the basic 2-channel MWR was first deployed at ARM CART sites Important advances are the development and refinement of the tipcal calibration method [1,2], and improvement of forward model radiative transfer algorithms [3,4]. However, the concern still remains that current instruments deployed by ARM may be inadequate to measure low amounts of PWV and IWL. In the case of water vapor, this is especially important because of the possibility of scaling and/or quality control of radiosondes by the water amount. Extremely dry conditions, with PWV less than 3 mm, commonly occur in Polar Regions during the winter months. Accurate measurements of the PWV during such dry conditions are needed to improve our understanding of the regional radiation energy budgets. The results of a 1999 experiment conducted at the ARM North Slope of Alaska/Adjacent Arctic Ocean (NSA/AAO) site during March of 1999 [5] have shown that the strength associated with the 183 GHz water vapor absorption line makes radiometry in this frequency regime suitable for measuring low amounts of PWV. As a portion of our research, we conducted another millimeter wave radiometric experiment at the NSA/AAO in March-April 2004. This experiment relied heavily on our experiences of the 1999 experiment. Particular attention was paid to issues of radiometric calibration and radiosonde intercomparisons. Our theoretical and experimental work also supplements efforts by industry (F. Solheim, Private Communication) to develop sub-millimeter radiometers for ARM deployment. In addition to quantitative improvement of water vapor measurements at cold temperature, the impact of adding millimeter-wave window channels to improve the sensitivity to arctic clouds was studied. We also deployed an Infrared Cloud Imager (ICI) during this experiment, both for measuring continuous day-night statistics of the study of cloud coverage and identifying conditions suitable for tipcal analysis. This system provided the first capability of determining spatial cloud statistics continuously in both day and night at the NSA site and has been used to demonstrate that biases exist in inferring cloud statistics from either zenith-pointing active sensors (lidars or radars) or sky imagers that rely on scattered sunlight in daytime and star maps at night [6].« less
Unmanned Aerial Vehicles and Weapons of Mass Destruction: A Lethal Combination?
1997-08-01
assessment ( BDA ), where they allow armed forces to avoid placing pilots at risk. They have also been used to gather nonmilitary information in... BDA purposes. In fact, the Pioneer UAV was praised as "the single most valuable intelligence collector" in the war against Iraq.6 They have proved to...carries half the weapon’s total energy. Finally, as the explosion takes on the familiar " mushroom " shape, winds suck back into the cloud, adding to the
Classification of Clouds in Satellite Imagery Using Adaptive Fuzzy Sparse Representation
Jin, Wei; Gong, Fei; Zeng, Xingbin; Fu, Randi
2016-01-01
Automatic cloud detection and classification using satellite cloud imagery have various meteorological applications such as weather forecasting and climate monitoring. Cloud pattern analysis is one of the research hotspots recently. Since satellites sense the clouds remotely from space, and different cloud types often overlap and convert into each other, there must be some fuzziness and uncertainty in satellite cloud imagery. Satellite observation is susceptible to noises, while traditional cloud classification methods are sensitive to noises and outliers; it is hard for traditional cloud classification methods to achieve reliable results. To deal with these problems, a satellite cloud classification method using adaptive fuzzy sparse representation-based classification (AFSRC) is proposed. Firstly, by defining adaptive parameters related to attenuation rate and critical membership, an improved fuzzy membership is introduced to accommodate the fuzziness and uncertainty of satellite cloud imagery; secondly, by effective combination of the improved fuzzy membership function and sparse representation-based classification (SRC), atoms in training dictionary are optimized; finally, an adaptive fuzzy sparse representation classifier for cloud classification is proposed. Experiment results on FY-2G satellite cloud image show that, the proposed method not only improves the accuracy of cloud classification, but also has strong stability and adaptability with high computational efficiency. PMID:27999261
NASA Astrophysics Data System (ADS)
Putman, W. M.; Suarez, M.
2009-12-01
The Goddard Earth Observing System Model (GEOS-5), an earth system model developed in the NASA Global Modeling and Assimilation Office (GMAO), has integrated the non-hydrostatic finite-volume dynamical core on the cubed-sphere grid. The extension to a non-hydrostatic dynamical framework and the quasi-uniform cubed-sphere geometry permits the efficient exploration of global weather and climate modeling at cloud permitting resolutions of 10- to 4-km on today's high performance computing platforms. We have explored a series of incremental increases in global resolution with GEOS-5 from it's standard 72-level 27-km resolution (~5.5 million cells covering the globe from the surface to 0.1 hPa) down to 3.5-km (~3.6 billion cells). We will present results from a series of forecast experiments exploring the impact of the non-hydrostatic dynamics at transition resolutions of 14- to 7-km, and the influence of increased horizontal/vertical resolution on convection and physical parameterizations within GEOS-5. Regional and mesoscale features of 5- to 10-day weather forecasts will be presented and compared with satellite observations. Our results will highlight the impact of resolution on the structure of cloud features including tropical convection and tropical cyclone predicability, cloud streets, von Karman vortices, and the marine stratocumulus cloud layer. We will also present experiment design and early results from climate impact experiments for global non-hydrostatic models using GEOS-5. Our climate experiments will focus on support for the Year of Tropical Convection (YOTC). We will also discuss a seasonal climate time-slice experiment design for downscaling coarse resolution century scale climate simulations to global non-hydrostatic resolutions of 14- to 7-km with GEOS-5.
Coherent Forward Broadening in Cold Atom Clouds
NASA Astrophysics Data System (ADS)
Sutherland, R. T.; Robicheaux, Francis
2016-05-01
It is shown that homogeneous line-broadening in a diffuse cold atom cloud is proportional to the resonant optical depth of the cloud. Further, it is demonstrated how the strong directionality of the coherent interactions causes the cloud's spectra to depend strongly on its shape, even when the cloud is held at constant densities. These two numerical observations can be predicted analytically by extending the single photon wavefunction model. Lastly, elongating a cloud along the line of laser propagation causes the excitation probability distribution to deviate from the exponential decay predicted by the Beer-Lambert law to the extent where the atoms in the back of the cloud are more excited than the atoms in the front. These calculations are conducted at low densities relevant to recent experiments. This work was supported by the National Science Foundation under Grant No. 1404419-PHY.
The Real-Time Monitoring Service Platform for Land Supervision Based on Cloud Integration
NASA Astrophysics Data System (ADS)
Sun, J.; Mao, M.; Xiang, H.; Wang, G.; Liang, Y.
2018-04-01
Remote sensing monitoring has become the important means for land and resources departments to strengthen supervision. Aiming at the problems of low monitoring frequency and poor data currency in current remote sensing monitoring, this paper researched and developed the cloud-integrated real-time monitoring service platform for land supervision which enhanced the monitoring frequency by acquiring the domestic satellite image data overall and accelerated the remote sensing image data processing efficiency by exploiting the intelligent dynamic processing technology of multi-source images. Through the pilot application in Jinan Bureau of State Land Supervision, it has been proved that the real-time monitoring technical method for land supervision is feasible. In addition, the functions of real-time monitoring and early warning are carried out on illegal land use, permanent basic farmland protection and boundary breakthrough in urban development. The application has achieved remarkable results.
Simulation of Asia Dust and Cloud Interaction Over Pacific Ocean During Pacdex
NASA Astrophysics Data System (ADS)
Long, X.; Huang, J.; Cheng, C.; Wang, W.
2007-12-01
The effect of dust plume on the Pacific cloud systems and the associated radiative forcing is an outstanding problem for understanding climate change. Many studies showing that dust aerosol might be a good absorber for solar radiation, at the same time dust aerosols could affect the cloud's formation and precipitation by its capability as cloud condensation nuclei (CCN) and ice forming nuclei (IFN). But the role of aerosols in clouds and precipitation is very complex. Simulation of interaction between cloud and dust aerosols requires recognition that the aerosol cloud system comprises coupled components of dynamics, aerosol and cloud microphysics, radiation processes. In this study, we investigated the interaction between dust aerosols and cloud with WRF which coupled with detailed cloud microphysics processes and dust process. The observed data of SACOL (Semi-Arid Climate and Environment Observatory of Lanzhou University) and PACDEX (Pacific Dust Experiment) is used as the initialization which include the vertical distributions and concentration of dust particles. Our results show that dust aerosol not only impacts cloud microphysical processes but also cloud microstructure; Dust aerosols can act as effective ice nuclei and intensify the ice-forming processes.
Rain-shadow: An area harboring "Gray Ocean" clouds
NASA Astrophysics Data System (ADS)
Padmakumari, B.; Maheskumar, R. S.; Harikishan, G.; Morwal, S. B.; Kulkarni, J. R.
2018-06-01
The characteristics of monsoon convective clouds over the rain-shadow region of north peninsular India have been investigated using in situ aircraft cloud microphysical observations collected during Cloud Aerosol Interaction and Precipitation Enhancement EXperiment (CAIPEEX). The parameters considered for characterization are: liquid water content (LWC), cloud vertical motion (updraft, downdraft: w), cloud droplet number concentration (CDNC) and effective radius (Re). The results are based on 15 research flights which were conducted from the base station Hyderabad during summer monsoon season. The clouds studied were developing congestus. The clouds have low CDNC and low updraft values resembling the oceanic convective clouds. The super-saturation in clouds is found to be low (≤0.2%) due to low updrafts. The land surface behaves like ocean surface during monsoon as deduced from Bowen ratio. Microphysically the clouds showed oceanic characteristics. However, these clouds yield low rainfall due to their low efficiency (mean 14%). The cloud parameters showed a large variability; hence their characteristic values are reported in terms of median values. These values will serve the numerical models for rainfall simulations over the region and also will be useful as a scientific basis for cloud seeding operations to increase the rainfall efficiency. The study revealed that monsoon convective clouds over the rain-shadow region are of oceanic type over the gray land, and therefore we christen them as "Gray Ocean" clouds.
NASA Technical Reports Server (NTRS)
Wang, Pi-Huan; Minnis, Patrick; McCormick, M. Patrick; Kent, Geoffrey S.; Yue, Glenn K.; Young, David F.; Skeens, Kristi M.
1998-01-01
The tropical cloud data obtained by the satellite instrument of the Stratospheric Aerosol and Gas Experiment (SAGE) II from October 1984 to May 1991 have been used to study cloud vertical distribution, including thickness and multilayer structure, and to estimate cloud optical depth. The results indicate that the SAGE-II-observed clouds are generally optically thin clouds, corresponding to a range of optical depth between approximately 8 x 10(exp -4) and 3 x 10(exp -1) with a mean of about 0.035. Two-thirds are classified as subvisual cirrus and one-third thin cirrus. Clouds between 2- to 3-km thick occur most frequently. Approximately 30% of the SAGE II cloud measurements are isolated single-layer clouds, while 65% are high clouds contiguous with an underlying opaque cloud that terminates the SAGE II profile. Thin clouds above detached opaque clouds at altitudes greater than 6.5 km occur less often. Only about 3% of the SAGE II single-layer clouds are located above the tropopause, while 58% of the cloud layers never reach the tropopause. More than one-third of the clouds appear at the tropopause. This study also shows that clouds occur more frequently and extend higher above the tropopause over the western Pacific than than over the eastern Pacific, especially during northern winter. The uncertainty of the derived results due to the SAGE II sampling constraints, data processing, and cloud characteristics is discussed.
NASA Technical Reports Server (NTRS)
Consiglio, Maria C.; Wilson, Sara R.; Sturdy, James; Murdoch, Jennifer L.; Wing, David J.
2010-01-01
A human-in-the-loop (HITL) simulation experiment was conducted by the National Aeronautics and Space Administration (NASA) to assess airline transport pilots performance and reported acceptance of the use of procedures relying on airborne separation assistance and trajectory management tools. This study was part of a larger effort involving two NASA centers that includes multiple HITL experiments planned over the next few years to evaluate the use of automated separation assurance (SA) tools by both air traffic controllers and pilots. This paper presents results of measured pilot response delay that subject pilots incurred when interacting with cockpit tools for SA and discusses possible implications for future concept and procedures design.
Zao, John K.; Gan, Tchin-Tze; You, Chun-Kai; Chung, Cheng-En; Wang, Yu-Te; Rodríguez Méndez, Sergio José; Mullen, Tim; Yu, Chieh; Kothe, Christian; Hsiao, Ching-Teng; Chu, San-Liang; Shieh, Ce-Kuen; Jung, Tzyy-Ping
2014-01-01
EEG-based Brain-computer interfaces (BCI) are facing basic challenges in real-world applications. The technical difficulties in developing truly wearable BCI systems that are capable of making reliable real-time prediction of users' cognitive states in dynamic real-life situations may seem almost insurmountable at times. Fortunately, recent advances in miniature sensors, wireless communication and distributed computing technologies offered promising ways to bridge these chasms. In this paper, we report an attempt to develop a pervasive on-line EEG-BCI system using state-of-art technologies including multi-tier Fog and Cloud Computing, semantic Linked Data search, and adaptive prediction/classification models. To verify our approach, we implement a pilot system by employing wireless dry-electrode EEG headsets and MEMS motion sensors as the front-end devices, Android mobile phones as the personal user interfaces, compact personal computers as the near-end Fog Servers and the computer clusters hosted by the Taiwan National Center for High-performance Computing (NCHC) as the far-end Cloud Servers. We succeeded in conducting synchronous multi-modal global data streaming in March and then running a multi-player on-line EEG-BCI game in September, 2013. We are currently working with the ARL Translational Neuroscience Branch to use our system in real-life personal stress monitoring and the UCSD Movement Disorder Center to conduct in-home Parkinson's disease patient monitoring experiments. We shall proceed to develop the necessary BCI ontology and introduce automatic semantic annotation and progressive model refinement capability to our system. PMID:24917804
Zao, John K; Gan, Tchin-Tze; You, Chun-Kai; Chung, Cheng-En; Wang, Yu-Te; Rodríguez Méndez, Sergio José; Mullen, Tim; Yu, Chieh; Kothe, Christian; Hsiao, Ching-Teng; Chu, San-Liang; Shieh, Ce-Kuen; Jung, Tzyy-Ping
2014-01-01
EEG-based Brain-computer interfaces (BCI) are facing basic challenges in real-world applications. The technical difficulties in developing truly wearable BCI systems that are capable of making reliable real-time prediction of users' cognitive states in dynamic real-life situations may seem almost insurmountable at times. Fortunately, recent advances in miniature sensors, wireless communication and distributed computing technologies offered promising ways to bridge these chasms. In this paper, we report an attempt to develop a pervasive on-line EEG-BCI system using state-of-art technologies including multi-tier Fog and Cloud Computing, semantic Linked Data search, and adaptive prediction/classification models. To verify our approach, we implement a pilot system by employing wireless dry-electrode EEG headsets and MEMS motion sensors as the front-end devices, Android mobile phones as the personal user interfaces, compact personal computers as the near-end Fog Servers and the computer clusters hosted by the Taiwan National Center for High-performance Computing (NCHC) as the far-end Cloud Servers. We succeeded in conducting synchronous multi-modal global data streaming in March and then running a multi-player on-line EEG-BCI game in September, 2013. We are currently working with the ARL Translational Neuroscience Branch to use our system in real-life personal stress monitoring and the UCSD Movement Disorder Center to conduct in-home Parkinson's disease patient monitoring experiments. We shall proceed to develop the necessary BCI ontology and introduce automatic semantic annotation and progressive model refinement capability to our system.
Oubel, Estanislao; Bonnard, Eric; Sueoka-Aragane, Naoko; Kobayashi, Naomi; Charbonnier, Colette; Yamamichi, Junta; Mizobe, Hideaki; Kimura, Shinya
2015-02-01
Lesion volume is considered as a promising alternative to Response Evaluation Criteria in Solid Tumors (RECIST) to make tumor measurements more accurate and consistent, which would enable an earlier detection of temporal changes. In this article, we report the results of a pilot study aiming at evaluating the effects of a consensual lesion selection on volume-based response (VBR) assessments. Eleven patients with lung computed tomography scans acquired at three time points were selected from Reference Image Database to Evaluate Response to therapy in lung cancer (RIDER) and proprietary databases. Images were analyzed according to RECIST 1.1 and VBR criteria by three readers working in different geographic locations. Cloud solutions were used to connect readers and carry out a consensus process on the selection of lesions used for computing response. Because there are not currently accepted thresholds for computing VBR, we have applied a set of thresholds based on measurement variability (-35% and +55%). The benefit of this consensus was measured in terms of multiobserver agreement by using Fleiss kappa (κfleiss) and corresponding standard errors (SE). VBR after consensual selection of target lesions allowed to obtain κfleiss = 0.85 (SE = 0.091), which increases up to 0.95 (SE = 0.092), if an extra consensus on new lesions is added. As a reference, the agreement when applying RECIST without consensus was κfleiss = 0.72 (SE = 0.088). These differences were found to be statistically significant according to a z-test. An agreement on the selection of lesions allows reducing the inter-reader variability when computing VBR. Cloud solutions showed to be an interesting and feasible strategy for standardizing response evaluations, reducing variability, and increasing consistency of results in multicenter clinical trials. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Xu, Kuan-Man; Luo, Yali; Morrison, Hugh; Mcfarquhar, G.M.
2008-01-01
Single-layer mixed-phase stratiform (MPS) Arctic clouds, which formed under conditions of large surface heat flux combined with general subsidence during a subperiod of the Atmospheric Radiation Measurement (ARM) Program Mixed-Phase Arctic Cloud Experiment (M-PACE), are simulated with a cloud resolving model (CRM). The CRM is implemented with either an advanced two-moment (M05) or a commonly used one-moment (L83) bulk microphysics scheme and a state-of-the-art radiative transfer scheme. The CONTROL simulation, that uses the M05 scheme and observed aerosol size distribution and ice nulei (IN) number concentration, reproduces the magnitudes and vertical structures of cloud liquid water content (LWC), total ice water content (IWC), number concentration and effective radius of cloud droplets as suggested by the M-PACE observations. It underestimates ice crystal number concentrations by an order of magnitude and overestimates effective radius of ice crystals by a factor of 2-3. The OneM experiment, that uses the L83 scheme, produces values of liquid water path (LWP) and ice plus snow water path (ISWP) that were about 30% and 4 times, respectively, of those produced by the CONTROL. Its vertical profile of IWC exhibits a bimodal distribution in contrast to the constant distribution of IWC produced in the CONTROL and observations.
Challenges and opportunities of cloud computing for atmospheric sciences
NASA Astrophysics Data System (ADS)
Pérez Montes, Diego A.; Añel, Juan A.; Pena, Tomás F.; Wallom, David C. H.
2016-04-01
Cloud computing is an emerging technological solution widely used in many fields. Initially developed as a flexible way of managing peak demand it has began to make its way in scientific research. One of the greatest advantages of cloud computing for scientific research is independence of having access to a large cyberinfrastructure to fund or perform a research project. Cloud computing can avoid maintenance expenses for large supercomputers and has the potential to 'democratize' the access to high-performance computing, giving flexibility to funding bodies for allocating budgets for the computational costs associated with a project. Two of the most challenging problems in atmospheric sciences are computational cost and uncertainty in meteorological forecasting and climate projections. Both problems are closely related. Usually uncertainty can be reduced with the availability of computational resources to better reproduce a phenomenon or to perform a larger number of experiments. Here we expose results of the application of cloud computing resources for climate modeling using cloud computing infrastructures of three major vendors and two climate models. We show how the cloud infrastructure compares in performance to traditional supercomputers and how it provides the capability to complete experiments in shorter periods of time. The monetary cost associated is also analyzed. Finally we discuss the future potential of this technology for meteorological and climatological applications, both from the point of view of operational use and research.
Chance Encounter with a Stratospheric Kerosene Rocket Plume from Russia over California
NASA Technical Reports Server (NTRS)
Newman, P. A.; Wilson, J. C.; Ross, M. N.; Brock, C.; Sheridan, P.; Schoeberl, M. R.; Lait, L. R.; Bui, T. P.; Loewenstein, M.
1999-01-01
During a routine ER-2 aircraft high-altitude test flight on April 18, 1997, an unusual aerosol cloud was detected at 20 km altitude near the California coast at about 370 degrees N latitude. Not visually observed by the ER-2 pilot, the cloud was characterized bv high concentration of soot and sulfate aerosol in a region over 100 km in horizontal extent indicating that the source of the plume was a large hydrocarbon fueled vehicle, most likely a launch vehicle powered only by rocket motors burning liquid oxygen and kerosene. Two Russian Soyuz rockets could conceivably have produced the plume. The first was launched from the Baikonur Cosmodrome, Kazakhstan on April 6th; the second was launched from Plesetsk, Russia on April 9. Air parcel trajectory calculations and long-lived tracer gas concentrations in the cloud indicate that the Baikonur rocket launch is the most probable source of the plume. The parcel trajectory calculations do not unambiguously trace the transport of the Soyuz plume from Asia to North America, illustrating serious flaws in the point-to-point trajectory calculations. This chance encounter represents the only measurement of the stratospheric effects of emissions from a rocket powered exclusively with hydrocarbon fuel.
NASA Technical Reports Server (NTRS)
Sugita, S.; Heineck, J. T.; Schultz, P. H.
2000-01-01
Chemical reactions within impact-induced vapor clouds were observed in laboratory experiments using a spectroscopic method. The results indicate that projectile-derived carbon-rich vapor reacts intensively with atmospheric nitrogen.
Condensed Acids In Antartic Stratospheric Clouds
NASA Technical Reports Server (NTRS)
Pueschel, R. F.; Snetsinger, K. G.; Toon, O. B.; Ferry, G. V.; Starr, W. L.; Oberbeck, V. R.; Chan, K. R.; Goodman, J. K.; Livingston, J. M.; Verma, S.;
1992-01-01
Report dicusses nitrate, sulfate, and chloride contents of stratospheric aerosols during 1987 Airborne Antarctic Ozone Experiment. Emphasizes growth of HNO3*3H2O particles in polar stratospheric clouds. Important in testing theories concerning Antarctic "ozone hole".
First results from the THOR experiment imaging thunderstorm activity from the ISS.
NASA Astrophysics Data System (ADS)
Chanrion, Olivier; Neubert, Torsten; Mogensen, Andreas; Yair, Yoav; Stendel, Martin; Larsen, Niels
2016-04-01
Video imaging from the THOR experiment conducted on International Space Station by the Danish astronaut Andreas Mogensen has been analyzed. The observations we report in this paper were taken with a color camera from the vantage point of the Cupola, tracking thunderstorm activity over the Bay of Bengal. Among many lightning, the observations contain a sprite, a blue jet and numerous small blue discharge regions at the top of a tall cumulonimbus cloud. The latter are interpreted as electric discharges between layers at the uppermost layers of the cloud and to the screening layer formed at the very edge between the cloud and the surrounding atmosphere. The observations are the first of their kind and give new insights into the charge structure at the top of clouds in the tropical tropopause regions, a region that is difficult to observe and to access.
NASA Technical Reports Server (NTRS)
Mulholland, J. Derral; Singer, S. Fred; Oliver, John P.; Weinberg, Jerry L.; Cooke, William J.; Montague, Nancy L.; Wortman, Jim J.; Kassel, Phillip C.; Kinard, William H.
1992-01-01
The purpose of the Interplanetary Dust Experiment (IDE) on the Long Duration Exposure Facility (LDEF) was to sample the cosmic dust environment and to use the spatio-temporal aspect of the experiment to distinguish between the various components of the environment: zodiacal cloud, beta meteoroids, meteor streams, interstellar dust, and orbital debris. It was found that the introduction of precise time and even rudimentary directionality as co-lateral observables in sampling the particulate environment in near-Earth space produces an enormous qualitative improvement in the information content of the impact data. The orbital debris population is extremely clumpy, being dominated by persistent clouds in which the fluxes may rise orders of magnitude above the background. The IDE data suggest a strategy to minimize the damage to sensitive spacecraft components, using the observed characteristics of cloud encounters.
Design and deployment of an elastic network test-bed in IHEP data center based on SDN
NASA Astrophysics Data System (ADS)
Zeng, Shan; Qi, Fazhi; Chen, Gang
2017-10-01
High energy physics experiments produce huge amounts of raw data, while because of the sharing characteristics of the network resources, there is no guarantee of the available bandwidth for each experiment which may cause link congestion problems. On the other side, with the development of cloud computing technologies, IHEP have established a cloud platform based on OpenStack which can ensure the flexibility of the computing and storage resources, and more and more computing applications have been deployed on virtual machines established by OpenStack. However, under the traditional network architecture, network capability can’t be required elastically, which becomes the bottleneck of restricting the flexible application of cloud computing. In order to solve the above problems, we propose an elastic cloud data center network architecture based on SDN, and we also design a high performance controller cluster based on OpenDaylight. In the end, we present our current test results.
14 CFR 61.99 - Aeronautical experience.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aeronautical experience. 61.99 Section 61.99 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Recreational Pilots § 61.99...
PILOT-SCALE STUDIES ON THE INCINERATION OF ELECTRONICS INDUSTRY WASTE
The paper describes experiments performed on a pilot-scale rotary kiln incinerator to investigate the emissions and operational behavior during the incineration of consumer electronics waste. These experiments were targeted at destroying the organic components of printed circuit ...
NASA Astrophysics Data System (ADS)
Satyanarayana, M.; Radhakrishnan, S.-R.; Krishnakumar, V.; Mahadevan Pillai, V. P.; Raghunath, K.
2008-12-01
Cirrus clouds have been identified as one of the most uncertain component in the atmospheric research. It is known that cirrus clouds modulate the earth's climate through direct and indirect modification of radiation. The role of cirrus clouds depends mainly on their microphysical properties. To understand cirrus clouds better, we must observe and characterize their properties. In-situ observation of such clouds is a challenging experiment, as the clouds are located at high altitudes. Active remote sensing method based on lidar can detect high and thin cirrus clouds with good spatial and temporal resolution. We present the result obtained on the microphysical properties of the cirrus clouds at two Tropical stations namely Gadhanki, Tirupati (13.50 N, 79.20 E), India and Trivandrum (13.50 N, 770 E) Kerala, India from the ground based pulsed Nd: YAG lidar systems installed at the stations. A variant of the widely used Klett's lidar inversion method with range dependent scattering ratio is used for the present study for the retrieval of aerosol extinction and microphysical parameters of cirrus cloud.
Evaluating Clouds in Long-Term Cloud-Resolving Model Simulations with Observational Data
NASA Technical Reports Server (NTRS)
Zeng, Xiping; Tao, Wei-Kuo; Zhang, Minghua; Peters-Lidard, Christa; Lang, Stephen; Simpson, Joanne; Kumar, Sujay; Xie, Shaocheng; Eastman, Joseph L.; Shie, Chung-Lin;
2006-01-01
Two 20-day, continental midlatitude cases are simulated with a three-dimensional (3D) cloud-resolving model (CRM) and compared to Atmospheric Radiation Measurement (ARM) data. This evaluation of long-term cloud-resolving model simulations focuses on the evaluation of clouds and surface fluxes. All numerical experiments, as compared to observations, simulate surface precipitation well but over-predict clouds, especially in the upper troposphere. The sensitivity of cloud properties to dimensionality and other factors is studied to isolate the origins of the over prediction of clouds. Due to the difference in buoyancy damping between 2D and 3D models, surface precipitation fluctuates rapidly with time, and spurious dehumidification occurs near the tropopause in the 2D CRM. Surface fluxes from a land data assimilation system are compared with ARM observations. They are used in place of the ARM surface fluxes to test the sensitivity of simulated clouds to surface fluxes. Summertime simulations show that surface fluxes from the assimilation system bring about a better simulation of diurnal cloud variation in the lower troposphere.
TRAINING - GEMINI-TITAN (GT)-5 - TX
1965-06-18
S65-35563 (18 June 1965) --- Astronauts L. Gordon Cooper Jr. (left), command pilot; and Charles Conrad Jr., pilot, the prime crew of the Gemini-5 spaceflight, prepare their cameras while aboard a C-130 aircraft flying near Laredo, Texas. The two astronauts are taking part in a series of visual acuity experiments to aid them in learning to identify known terrestrial features under controlled conditions. Knowledge gained from these experiments will have later application for space pilots identifying terrestrial features from space. Dr. John Billingham, chief, Environmental Physiology Branch, Crew Systems Division, is in charge of the Visual Acuity Experiments.
NASA Astrophysics Data System (ADS)
Pedruzo-Bagazgoitia, Xabier; Lohou, Fabienne; Dione, Cheikh; Lothon, Marie; Kalthoff, Norbert; Adler, Bianca; Babić, Karmen; Vilà-Guerau de Arellano, Jordi
2017-04-01
The role of boundary-layer clouds as part of the Western African Monsoon system is investigated. The system encompasses the interaction between large-scale phenomena such as the (southerly) monsoon flow, the African Easterly Jet and the (northerly) Harmattan wind, and the role of smaller scale processes driven by turbulence and the sea-vegetation transition on the lower troposphere, such as the frequently observed nocturnal low-level jet. As observed during the DACCIWA project campaign, low stratocumulus clouds recurrently appear inland during the night, sometimes prevailing until the next afternoon while in other cases they break up in the morning and disappear or transform to convective clouds. These observations rise two research questions: Do surface conditions affect the cloud breakup? Is the direct or diffuse character of radiation relevant for the cloud transition? In our study we focus on the local effect of the surface and radiation on the breakup of stratocumulus and the subsequent transition to convective clouds during the morning transition. We design an idealized Large Eddy Simulation (LES) experiment in which the surface is coupled to the cloud dynamics based on radiosoundings launched during the campaign at the supersite of Savé (Benin), which is located about 180 km north of the Gulf of Guinea. This experiment includes the most relevant factors for the evolution of the boundary layer and stratocumulus in the morning. By systematically breaking down the complexity of the system, we study the relevance of atmospheric stability (by modifying the atmospheric lapse rates), and the partition of evaporation and sensible heat flux on the evolution, break up and transition of the stratocumulus cloud layer. Previous studies have shown that diffuse radiation controlled by clouds and aerosols can locally enhance evaporation. Therefore, particular emphasize is put on the determination of the role of direct and diffuse radiation during the cloud transition on the vegetated canopy, and the impact on the surface fluxes and cloud dynamics.
NASA Technical Reports Server (NTRS)
Fridlin, Ann; vanDiedenhoven, Bastiaan; Ackerman, Andrew S.; Avramov, Alexander; Mrowiec, Agnieszka; Morrison, Hugh; Zuidema, Paquita; Shupe, Matthew D.
2012-01-01
Observations of long-lived mixed-phase Arctic boundary layer clouds on 7 May 1998 during the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE)Arctic Cloud Experiment (ACE)Surface Heat Budget of the Arctic Ocean (SHEBA) campaign provide a unique opportunity to test understanding of cloud ice formation. Under the microphysically simple conditions observed (apparently negligible ice aggregation, sublimation, and multiplication), the only expected source of new ice crystals is activation of heterogeneous ice nuclei (IN) and the only sink is sedimentation. Large-eddy simulations with size-resolved microphysics are initialized with IN number concentration N(sub IN) measured above cloud top, but details of IN activation behavior are unknown. If activated rapidly (in deposition, condensation, or immersion modes), as commonly assumed, IN are depleted from the well-mixed boundary layer within minutes. Quasi-equilibrium ice number concentration N(sub i) is then limited to a small fraction of overlying N(sub IN) that is determined by the cloud-top entrainment rate w(sub e) divided by the number-weighted ice fall speed at the surface v(sub f). Because w(sub c)< 1 cm/s and v(sub f)> 10 cm/s, N(sub i)/N(sub IN)<< 1. Such conditions may be common for this cloud type, which has implications for modeling IN diagnostically, interpreting measurements, and quantifying sensitivity to increasing N(sub IN) (when w(sub e)/v(sub f)< 1, entrainment rate limitations serve to buffer cloud system response). To reproduce observed ice crystal size distributions and cloud radar reflectivities with rapidly consumed IN in this case, the measured above-cloud N(sub IN) must be multiplied by approximately 30. However, results are sensitive to assumed ice crystal properties not constrained by measurements. In addition, simulations do not reproduce the pronounced mesoscale heterogeneity in radar reflectivity that is observed.
NASA Astrophysics Data System (ADS)
Ansmann, A.; Tesche, M.; Althausen, D.; Müller, D.; Seifert, P.; Freudenthaler, V.; Heese, B.; Wiegner, M.; Pisani, G.; Knippertz, P.; Dubovik, O.
2008-02-01
Multiwavelength lidar, Sun photometer, and radiosonde observations were conducted at Ouarzazate (30.9°N, 6.9°W, 1133 m above sea level, asl), Morocco, in the framework of the Saharan Mineral Dust Experiment (SAMUM) in May-June 2006. The field site is close to the Saharan desert. Information on the depolarization ratio, backscatter and extinction coefficients, and lidar ratio of the dust particles, estimates of the available concentration of atmospheric ice nuclei at cloud level, profiles of temperature, humidity, and the horizontal wind vector as well as backward trajectory analysis are used to study cases of cloud formation in the dust with focus on heterogeneous ice formation. Surprisingly, most of the altocumulus clouds that form at the top of the Saharan dust layer, which reaches into heights of 4-7 km asl and has layer top temperatures of -8°C to -18°C, do not show any ice formation. According to the lidar observations the presence of a high number of ice nuclei (1-20 cm-3) does not automatically result in the obvious generation of ice particles, but the observations indicate that cloud top temperatures must typically reach values as low as -20°C before significant ice production starts. Another main finding is that liquid clouds are obviously required before ice crystals form via heterogeneous freezing mechanisms, and, as a consequence, that deposition freezing is not an important ice nucleation process. An interesting case with cloud seeding in the free troposphere above the dust layer is presented in addition. Small water clouds formed at about -30°C and produced ice virga. These virga reached water cloud layers several kilometers below the initiating cloud cells and caused strong ice production in these clouds at temperatures as high as -12°C to -15°C.
Cloud Detection of Optical Satellite Images Using Support Vector Machine
NASA Astrophysics Data System (ADS)
Lee, Kuan-Yi; Lin, Chao-Hung
2016-06-01
Cloud covers are generally present in optical remote-sensing images, which limit the usage of acquired images and increase the difficulty of data analysis, such as image compositing, correction of atmosphere effects, calculations of vegetation induces, land cover classification, and land cover change detection. In previous studies, thresholding is a common and useful method in cloud detection. However, a selected threshold is usually suitable for certain cases or local study areas, and it may be failed in other cases. In other words, thresholding-based methods are data-sensitive. Besides, there are many exceptions to control, and the environment is changed dynamically. Using the same threshold value on various data is not effective. In this study, a threshold-free method based on Support Vector Machine (SVM) is proposed, which can avoid the abovementioned problems. A statistical model is adopted to detect clouds instead of a subjective thresholding-based method, which is the main idea of this study. The features used in a classifier is the key to a successful classification. As a result, Automatic Cloud Cover Assessment (ACCA) algorithm, which is based on physical characteristics of clouds, is used to distinguish the clouds and other objects. In the same way, the algorithm called Fmask (Zhu et al., 2012) uses a lot of thresholds and criteria to screen clouds, cloud shadows, and snow. Therefore, the algorithm of feature extraction is based on the ACCA algorithm and Fmask. Spatial and temporal information are also important for satellite images. Consequently, co-occurrence matrix and temporal variance with uniformity of the major principal axis are used in proposed method. We aim to classify images into three groups: cloud, non-cloud and the others. In experiments, images acquired by the Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and images containing the landscapes of agriculture, snow area, and island are tested. Experiment results demonstrate the detection accuracy of the proposed method is better than related methods.
Cloud processing of organic compounds: Secondary organic aerosol and nitrosamine formation
NASA Astrophysics Data System (ADS)
Hutchings, James W., III
Cloud processing of atmospheric organic compounds has been investigated through field studies, laboratory experiments, and numerical modeling. Observational cloud chemistry studies were performed in northern Arizona and fog studies in central Pennsylvania. At both locations, the cloud and fogs showed low acidity due to neutralization by soil dust components (Arizona) and ammonia (Pennsylvania). The field observations showed substantial concentrations (20-5500 ng•L -1) of volatile organic compounds (VOC) in the cloud droplets. The potential generation of secondary organic aerosol mass through the processing of these anthropogenic VOCs was investigated through laboratory and modeling studies. Under simulated atmospheric conditions, in idealized solutions, benzene, toluene, ethylbenzene, and xylene (BTEX) degraded quickly in the aqueous phase with half lives of approximately three hours. The degradation process yielded less volatile products which would contribute to new aerosol mass upon cloud evaporation. However, when realistic cloud solutions containing natural organic matter were used in the experiments, the reaction kinetics decreased with increasing organic carbon content, resulting in half lives of approximately 7 hours. The secondary organic aerosol (SUA) mass formation potential of cloud processing of BTEX was evaluated. SOA mass formation by cloud processing of BTEX, while strongly dependent on the atmospheric conditions, could contribute up to 9% of the ambient atmospheric aerosol mass, although typically ˜1% appears realistic. Field observations also showed the occurrence of N-nitrosodimethylamine (NDMA), a potent carcinogen, in fogs and clouds (100-340 ng•L -1). Laboratory studies were conducted to investigate the formation of NDMA from nitrous acid and dimethylamine in the homogeneous aqueous phase within cloud droplets. While NDMA was produced in the cloud droplets, the low yields (<1%) observed could not explain observational concentrations. Therefore heterogeneous or gaseous formation of NDMA with partitioning to droplet must be the source of aqueous NDMA. Box-model calculations tended to demonstrate a predominance of a gas phase formation mechanism followed by partitioning into the cloud droplets. The calculations were consistent with field measurements of gaseous and aqueous NDMA concentrations. Measurements and model calculations showed that while NDMA is eventually photolyzed, it might persist in the atmosphere for hours.
Infrared experiments for spaceborne planetary atmospheres research. Full report
NASA Technical Reports Server (NTRS)
1981-01-01
The role of infrared sensing in atmospheric science is discussed and existing infrared measurement techniques are reviewed. Proposed techniques for measuring planetary atmospheres are criticized and recommended instrument developments for spaceborne investigations are summarized for the following phenomena: global and local radiative budget; radiative flux profiles; winds; temperature; pressure; transient and marginal atmospheres; planetary rotation and global atmospheric activity; abundances of stable constituents; vertical, lateral, and temporal distribution of abundances; composition of clouds and aerosols; radiative properties of clouds and aerosols; cloud microstructure; cloud macrostructure; and non-LTE phenomena.
MIE Lidar proposed for the German Space Shuttle Mission D2
NASA Technical Reports Server (NTRS)
Renger, W.; Endemann, M.; Quenzel, H.; Werner, C.
1986-01-01
Firm plans for a second German Spacelab mission (D2-mission), originally scheduled for late 1988 is basically a zero-g mission, but will also include earth observation experiments. On board the D2-facility will allow performance of a number of different measurements with the goal to obtain performance data (cloud top heights, height of the planetary boundary layer, optical thickness, and cloud base height of thin and medium thick clouds, ice/water phase discriminatin for clouds, tropopause height, tropaspheric height, tropospheric aerosols, and stratospheric aerosols.
Wiegmann, Douglas A; Goh, Juliana; O'Hare, David
2002-01-01
Visual flight rules (VFR) flight into instrument meteorological conditions (IMC) is a major safety hazard in general aviation. In this study we examined pilots' decisions to continue or divert from a VFR flight into IMC during a dynamic simulation of a cross-country flight. Pilots encountered IMC either early or later into the flight, and the amount of time and distance pilots flew into the adverse weather prior to diverting was recorded. Results revealed that pilots who encountered the deteriorating weather earlier in the flight flew longer into the weather prior to diverting and had more optimistic estimates of weather conditions than did pilots who encountered the deteriorating weather later in the flight. Both the time and distance traveled into the weather prior to diverting were negatively correlated with pilots' previous flight experience. These findings suggest that VFR flight into IMC may be attributable, at least in part, to poor situation assessment and experience rather than to motivational judgment that induces risk-taking behavior as more time and effort are invested in a flight. Actual or potential applications of this research include the design of interventions that focus on improving weather evaluation skills in addition to addressing risk-taking attitudes.
STS-93 Pilot Ashby works with the STL-B experiment on the middeck
2013-11-18
STS093-319-029 (23-27 July 1999) --- Astronaut Jeffrey S. Ashby, pilot, works with the Space Tissue Loss-B experiment on Columbia's middeck. The experiment is set up to observe cells in culture with a video microscope imaging system to record near-real-time interactions of detecting and inducing cellular responses (macromorphological changes).
Bullying Experiences of Child and Adolescent Mental Health Service-Users: A Pilot Survey
ERIC Educational Resources Information Center
Dyer, Kevin; Teggart, Tom
2007-01-01
Victims and perpetrators of bullying experience a variety of psychological problems. The aim of the current pilot study was to explore the bullying experiences of Child and Adolescent Mental Health (CAMHS) service-users. The investigation was conducted as a cross-sectional survey at a community-based specialist CAMH service. A modified version of…
Clouds of different colors: A prospective look at head and neck surgical resident call experience.
Melzer, Jonathan
2017-12-01
Graduate medical education programs typically set up call under the assumption that residents will have similar experiences. The terms black cloud and white cloud have frequently been used to describe residents with more difficult (black) or less difficult (white) call experiences. This study followed residents in the department of head and neck surgery during call to determine whether certain residents have a significantly different call experience than the norm. It is a prospective observational study conducted over 16 months in a tertiary care center with a resident training program in otolaryngology. Resident call data on total pages, consults, and operative interventions were examined, as well as subjective survey data about sleep and perceived difficulty of resident call. Analysis showed no significant difference in call activity (pages, consults, operative interventions) among residents. However, data from the resident call surveys revealed perceived disparities in call difficulty that were significant. Two residents were clearly labeled as black clouds compared to the rest. These residents did not have the highest average number of pages, consults, or operative interventions. This study suggests that factors affecting call perception are outside the objective, absolute workload. These results may be used to improve resident education on sleep training and nighttime patient management in the field of otolaryngology and may influence otolaryngology residency programs.
Remote sensing image segmentation based on Hadoop cloud platform
NASA Astrophysics Data System (ADS)
Li, Jie; Zhu, Lingling; Cao, Fubin
2018-01-01
To solve the problem that the remote sensing image segmentation speed is slow and the real-time performance is poor, this paper studies the method of remote sensing image segmentation based on Hadoop platform. On the basis of analyzing the structural characteristics of Hadoop cloud platform and its component MapReduce programming, this paper proposes a method of image segmentation based on the combination of OpenCV and Hadoop cloud platform. Firstly, the MapReduce image processing model of Hadoop cloud platform is designed, the input and output of image are customized and the segmentation method of the data file is rewritten. Then the Mean Shift image segmentation algorithm is implemented. Finally, this paper makes a segmentation experiment on remote sensing image, and uses MATLAB to realize the Mean Shift image segmentation algorithm to compare the same image segmentation experiment. The experimental results show that under the premise of ensuring good effect, the segmentation rate of remote sensing image segmentation based on Hadoop cloud Platform has been greatly improved compared with the single MATLAB image segmentation, and there is a great improvement in the effectiveness of image segmentation.
Secondary organic aerosol formation through cloud processing of aromatic VOCs
NASA Astrophysics Data System (ADS)
Herckes, P.; Hutchings, J. W.; Ervens, B.
2010-12-01
Field observations have shown substantial concentrations (20-5,500 ng L-1) of aromatic volatile organic compounds (VOC) in cloud droplets. The potential generation of secondary organic aerosol mass through the processing of these anthropogenic VOCs was investigated through laboratory and modeling studies. Under simulated atmospheric laboratory conditions, in idealized solutions, benzene, toluene, ethylbenzene, and xylene (BTEX) degraded quickly in the aqueous phase. The degradation process yielded less volatile products which would contribute to new aerosol mass upon cloud evaporation. However, when realistic cloud solutions containing natural organic matter were used in the experiments, the reaction rates decreased with increasing organic carbon content. Kinetic data derived from these experiments were used as input to a multiphase box model in order to evaluate the secondary organic aerosol (SOA) mass formation potential of cloud processing of BTEX. Model results will be presented that quantify the SOA amounts from these aqueous phase pathways. The efficiency of this multiphase SOA source will be compared to SOA yields from the same aromatics as treated in traditional SOA models that are restricted to gas phase oxidation and subsequent condensation on particles.
Piloting Changes to Changing Aircraft Dynamics: What Do Pilots Need to Know?
NASA Technical Reports Server (NTRS)
Trujillo, Anna C.; Gregory, Irene M.
2011-01-01
An experiment was conducted to quantify the effects of changing dynamics on a subject s ability to track a signal in order to eventually model a pilot adapting to changing aircraft dynamics. The data will be used to identify primary aircraft dynamics variables that influence changes in pilot s response and produce a simplified pilot model that incorporates this relationship. Each run incorporated a different set of second-order aircraft dynamics representing short period transfer function pitch attitude response: damping ratio, frequency, gain, zero location, and time delay. The subject s ability to conduct the tracking task was the greatest source of root mean square error tracking variability. As for the aircraft dynamics, the factors that affected the subjects ability to conduct the tracking were the time delay, frequency, and zero location. In addition to creating a simplified pilot model, the results of the experiment can be utilized in an advisory capacity. A situation awareness/prediction aid based on the pilot behavior and aircraft dynamics may help tailor pilot s inputs more quickly so that PIO or an upset condition can be avoided.
Classification and prediction of pilot weather encounters: A discriminant function analysis.
O'Hare, David; Hunter, David R; Martinussen, Monica; Wiggins, Mark
2011-05-01
Flight into adverse weather continues to be a significant hazard for General Aviation (GA) pilots. Weather-related crashes have a significantly higher fatality rate than other GA crashes. Previous research has identified lack of situational awareness, risk perception, and risk tolerance as possible explanations for why pilots would continue into adverse weather. However, very little is known about the nature of these encounters or the differences between pilots who avoid adverse weather and those who do not. Visitors to a web site described an experience with adverse weather and completed a range of measures of personal characteristics. The resulting data from 364 pilots were carefully screened and subject to a discriminant function analysis. Two significant functions were found. The first, accounting for 69% of the variance, reflected measures of risk awareness and pilot judgment while the second differentiated pilots in terms of their experience levels. The variables measured in this study enabled us to correctly discriminate between the three groups of pilots considerably better (53% correct classifications) than would have been possible by chance (33% correct classifications). The implications of these findings for targeting safety interventions are discussed.
NASA Technical Reports Server (NTRS)
Ragent, Boris
1993-01-01
The purpose of this study is to attempt to find correlations between data taken by experiments aboard the Pioneer-Venus Orbiter (PVO) and those obtained from Earth-based near-infrared (NIR) measurements of Venus during periods near inferior conjunction. Since the NIR measurements have been found to provide data on the middle atmosphere cloud morphology and motion, it is assumed that any correlations will also indicate that the PVO experiments are also documenting cloud behavior. If such correlations are found, then a further task is to attempt to study the long term behavior of the cloud features implied by the correlations. Many PVO data have been obtained over an extended period extending from 1978 until the PV demise in 1992. There exists a long, somewhat ill-conditioned time series of data that may contain valuable information on the long time, as well as short term behavior of the clouds, and, derivatively from cloud motion, atmospheric dynamics and wave activity in the Venus atmosphere. For example, determination of the zonal velocities of any OCPP (Cloud Photopolarimeter) 0.935 micron features could then be used for comparisons with data from other sources to attempt to fix the altitude region in which such features existed. A further task of this study is to attempt to correlate any features found in simultaneously obtained data, for example, the OCPP 0.365 and 0.935 micron data. The existence of such correlations may imply that data was obtained in overlapping altitude regions of the atmosphere.
NASA Astrophysics Data System (ADS)
Kim, S.; Yoon, S.; Venkata Ramana, M.; Ramanathan, V.; Nguyen, H.; Park, S.; Kim, M.
2009-12-01
Cheju Atmospheric Brown Cloud (ABC) Plume-Monsoon Experiment (CAPMEX), comprehsensive ground-based measurements and a series of data-gathering flights by specially equipped autonomous unmanned aerial vehicles (AUAVs) for aerosol and cloud, had conducted at Jeju (formerly, Cheju), South Korea during August-September 2008, to improve our understanding of how the reduction of anthropogenic emissions in China (so-called “great shutdown” ) during and after the Summer Beijing Olympic Games 2008 effcts on the air quliaty and radiation budgets and how atmospheric brown clouds (ABCs) influences solar radiation budget off Asian continent. Large numbers of in-situ and remote sensing instruments at the Gosan ABC observatory and miniaturized instruments on the aircraft measure a range of properties such as the quantity of soot, size-segregated aerosol particle numbers, total particle numbers, size-segregated cloud droplet numbers (only AUAV), aerosol scattering properties (only ground), aerosol vertical distribution, column-integrated aerosol properties, and meteorological variables. By integrating ground-level and high-elevation AUAV measurements with NASA-satellite observations (e.g., MODIS, CALIPSO), we investigate the long range transport of aerosols, the impact of ABCs on clouds, and the role of biogenic and anthropogenic aerosols on cloud condensation nuclei (CCN). In this talk, we will present the results from CAPMEX focusing on: (1) the characteristics of aerosol optical, physical and chemical properties at Gosan observatory, (2) aerosol solar heating calculated from the ground-based micro-pulse lidar and AERONET sun/sky radiometer synergy, and comparison with direct measurements from UAV, and (3) aerosol-cloud interactions in conjunction with measurements by satellites and Gosan observatory.
Global snowfall: A combined CloudSat, GPM, and reanalysis perspective.
NASA Astrophysics Data System (ADS)
Milani, Lisa; Kulie, Mark S.; Skofronick-Jackson, Gail; Munchak, S. Joseph; Wood, Norman B.; Levizzani, Vincenzo
2017-04-01
Quantitative global snowfall estimates derived from multi-year data records will be presented to highlight recent advances in high latitude precipitation retrievals using spaceborne observations. More specifically, the analysis features the 2006-2016 CloudSat Cloud Profiling Radar (CPR) and the 2014-2016 Global Precipitation (GPM) Microwave Imager (GMI) and Dual-frequency Precipitation Radar (DPR) observational datasets and derived products. The ERA-Interim reanalysis dataset is also used to define the meteorological context and an independent combined modeling/observational evaluation dataset. An overview is first provided of CloudSat CPR-derived results that have stimulated significant recent research regarding global snowfall, including seasonal analyses of unique snowfall modes. GMI and DPR global annual snowfall retrievals are then evaluated against the CloudSat estimates to highlight regions where the datasets provide both consistent and diverging snowfall estimates. A hemispheric seasonal analysis for both datasets will also be provided. These comparisons aim at providing a unified global snowfall characterization that leverages the respective instrument's strengths. Attention will also be devoted to regions around the globe that experience unique snowfall modes. For instance, CloudSat has demonstrated an ability to effectively discern snowfall produced by shallow cumuliform cloud structures (e.g., lake/ocean-induced convective snow produced by air/water interactions associated with seasonal cold air outbreaks). The CloudSat snowfall database also reveals prevalent seasonal shallow cumuliform snowfall trends over climate-sensitive regions like the Greenland Ice Sheet. Other regions with unique snowfall modes, such as the US East Coast winter storm track zone that experiences intense snowfall rates directly associated with strong low pressure systems, will also be highlighted to demonstrate GPM's observational effectiveness. Linkages between CloudSat and GPM global snowfall analyses and independent ERA-Interim datasets will also be presented as a final evaluation exercise.
Confronting Models with Data: The GEWEX Cloud Systems Study
NASA Technical Reports Server (NTRS)
Randall, David; Curry, Judith; Duynkerke, Peter; Krueger, Steven; Moncrieff, Mitchell; Ryan, Brian; Starr, David OC.; Miller, Martin; Rossow, William; Tselioudis, George
2002-01-01
The GEWEX Cloud System Study (GCSS; GEWEX is the Global Energy and Water Cycle Experiment) was organized to promote development of improved parameterizations of cloud systems for use in climate and numerical weather prediction models, with an emphasis on the climate applications. The strategy of GCSS is to use two distinct kinds of models to analyze and understand observations of the behavior of several different types of clouds systems. Cloud-system-resolving models (CSRMs) have high enough spatial and temporal resolutions to represent individual cloud elements, but cover a wide enough range of space and time scales to permit statistical analysis of simulated cloud systems. Results from CSRMs are compared with detailed observations, representing specific cases based on field experiments, and also with statistical composites obtained from satellite and meteorological analyses. Single-column models (SCMs) are the surgically extracted column physics of atmospheric general circulation models. SCMs are used to test cloud parameterizations in an un-coupled mode, by comparison with field data and statistical composites. In the original GCSS strategy, data is collected in various field programs and provided to the CSRM Community, which uses the data to "certify" the CSRMs as reliable tools for the simulation of particular cloud regimes, and then uses the CSRMs to develop parameterizations, which are provided to the GCM Community. We report here the results of a re-thinking of the scientific strategy of GCSS, which takes into account the practical issues that arise in confronting models with data. The main elements of the proposed new strategy are a more active role for the large-scale modeling community, and an explicit recognition of the importance of data integration.
Evaluation of a Cloud Resolving Model Using TRMM Observations for Multiscale Modeling Applications
NASA Technical Reports Server (NTRS)
Posselt, Derek J.; L'Ecuyer, Tristan; Tao, Wei-Kuo; Hou, Arthur Y.; Stephens, Graeme L.
2007-01-01
The climate change simulation community is moving toward use of global cloud resolving models (CRMs), however, current computational resources are not sufficient to run global CRMs over the hundreds of years necessary to produce climate change estimates. As an intermediate step between conventional general circulation models (GCMs) and global CRMs, many climate analysis centers are embedding a CRM in each grid cell of a conventional GCM. These Multiscale Modeling Frameworks (MMFs) represent a theoretical advance over the use of conventional GCM cloud and convection parameterizations, but have been shown to exhibit an overproduction of precipitation in the tropics during the northern hemisphere summer. In this study, simulations of clouds, precipitation, and radiation over the South China Sea using the CRM component of the NASA Goddard MMF are evaluated using retrievals derived from the instruments aboard the Tropical Rainfall Measuring Mission (TRMM) satellite platform for a 46-day time period that spans 5 May - 20 June 1998. The NASA Goddard Cumulus Ensemble (GCE) model is forced with observed largescale forcing derived from soundings taken during the intensive observing period of the South China Sea Monsoon Experiment. It is found that the GCE configuration used in the NASA Goddard MMF responds too vigorously to the imposed large-scale forcing, accumulating too much moisture and producing too much cloud cover during convective phases, and overdrying the atmosphere and suppressing clouds during monsoon break periods. Sensitivity experiments reveal that changes to ice cloud microphysical parameters have a relatively large effect on simulated clouds, precipitation, and radiation, while changes to grid spacing and domain length have little effect on simulation results. The results motivate a more detailed and quantitative exploration of the sources and magnitude of the uncertainty associated with specified cloud microphysical parameters in the CRM components of MMFs.
Perspective traffic display format and airline pilot traffic avoidance
NASA Technical Reports Server (NTRS)
Ellis, Stephen R.; Mcgreevy, Michael W.; Hitchcock, Robert J.
1987-01-01
Part-task experiments have examined perspective projections of cockpit displays of traffic information as a means of presenting aircraft separation information to airline pilots. Ten airline pilots served as subjects in an experiment comparing the perspective projection with plan-view projections of the same air traffic situations. The pilots' task was to monitor the traffic display in order to decide if an avoidance maneuver was needed. Pilots took more time to select avoidance maneuvers with a conventional plan-view display than with an experimental perspective display. In contrast to previous results, if the pilots selected a maneuver with the perspective display, they were more likely to choose one with a vertical component. Tabulation of the outcomes of their initial avoidance decisions with both perspective and plan-view displays showed that they were more likely to achieve required separation with maneuvers chosen with the aid of perspective displays.
Case reports of insulin-dependent glider pilots in the United Kingdom.
Saundby, R P
1998-10-01
Insulin-dependent diabetics have not been licensed to fly as pilots. In the United Kingdom, the standards for flying gliders solo were adopted from those required for driving licences, allowing diabetics to fly gliders. No accidents had been reported. My hypothesis was that insulin-dependent diabetics can fly as pilots without danger. A survey was conducted among insulin-dependent glider pilots, using a questionnaire to determine their flying experience and establish any difficulties arising from their disease. Respondents reported that their blood sugar level could be managed in flight and that while complications of diabetes occurred, they had not presented a flight safety hazard. Insulin dependent diabetic pilots flying solo recreational aircraft are not at greater risk than when driving road vehicles. The decision by the British Gliding Association to allow insulin dependent pilots to fly gliders solo has been justified by experience.
The FIRE Cirrus Science Results 1993
NASA Technical Reports Server (NTRS)
Mcdougal, David S. (Editor)
1993-01-01
FIRE (First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment) is a U.S. cloud-radiation research program that seeks to improve our basic understanding and parameterizations of cirrus and marine stratocumulus cloud systems and ISCCP data products. The FIRE Cirrus Science Conference was held in Breckenridge, CO, 14-17 Jun. 1993, to present results of cirrus research for the second phase of FIRE (1989-present) and to refine cirrus research goals and priorities for the next phase of FIRE (1994-future). This Conference Publication contains the text of short papers presented at the conference. The papers describe research analyses of data collected at the Cirrus Intensive Field Observations-2 field experiment conducted in Kansas, 13 Nov. - 7 Dec. 1991.
Bioretention for stormwater quality improvement in Texas : pilot experiments.
DOT National Transportation Integrated Search
2010-07-01
This report summarizes the results of pilot-scale bioretention experiments. Five steel boxes of 6 ft (L) 6 ft : (W) 4 ft (D) were constructed, each of which has a different type of vegetation: (1) shrubs, (2) grass : species in Texas Department...
NASA Astrophysics Data System (ADS)
Schlesinger, Robert E.
1988-05-01
An anelastic three-dimensional model is used to investigate the effects of stratospheric temperature lapse rate on cloud top height/temperature structure for strongly sheared mature isolated midlatitude thunderstorms. Three comparative experiments are performed, differing only with respect to the stratospheric stability. The assumed stratospheric lapse rate is 0 K km1 (isothermal) in the first experiment, 3 K km1 in the second, and 3 K km1 (inversion) in the third.Kinematic storm structure is very similar in all three cases, especially in the troposphere. A strong quasi-steady updraft evolves splitting into a dominant cyclonic overshooting right-mover and a weaker anticyclonic left-mover that does not reach the tropopause. Strongest downdrafts occur at low to middle levels between the updrafts, and in the lower stratosphere a few kilometers upshear and downshear of the tapering updraft summit.Each storm shows a cloud-top thermal couplet, relatively cold near and upshear of the summit, and with a `close-in' warm region downshear. Both cold and warm regions become warmer, with significant morphological changes and a lowering of the cloud summit, as stratospheric stability is increased, though the temperature spread is not greatly affected.The coldest and highest cloud-top points are nearly colocated in the absence of a stratospheric inversion, but the coldest point is offset well upshear of the summit when an inversion is present. The cold region as a whole in each case shows at least a transient `V' shape, with the arms pointing downshear, although this shape is persistent only with the inversion.In the experiment with a 3 K km1 stratospheric lapse rate (weakest stability), the warm region is small and separates into two spots with secondary cold spots downshear of them. The warm region becomes larger, and remains single, as stratospheric stability increase. In each run, the warm regions are not accompanied by corresponding cloud-top height minima except very briefly.The cold cloud-top points are near or slightly downwind of relative vertical velocity maxima, usually positive, while the warm points are imbedded in subsidence downwind of the principal cloud-top downdraft core. The storm-relative cloud-top horizontal wind fields are consistent with the `V' shape of the cold region, showing strong diffluent flow directed downshear along the flanks from an upshear stagnation zone.
NASA Technical Reports Server (NTRS)
Cheng, Anning; Xu, Kuan-Man
2015-01-01
Five-year simulation experiments with a multi-scale modeling Framework (MMF) with a advanced intermediately prognostic higher-order turbulence closure (IPHOC) in its cloud resolving model (CRM) component, also known as SPCAM-IPHOC (super parameterized Community Atmospheric Model), are performed to understand the fast tropical (30S-30N) cloud response to an instantaneous doubling of CO2 concentration with SST held fixed at present-day values. SPCAM-IPHOC has substantially improved the low-level representation compared with SPCAM. It is expected that the cloud responses to greenhouse warming in SPCAM-IPHOC is more realistic. The change of rising motion, surface precipitation, cloud cover, and shortwave and longwave cloud radiative forcing in SPCAM-IPHOC from the greenhouse warming will be presented in the presentation.
Cloud and traditional videoconferencing technology for telemedicine and distance learning.
Liu, Wei-Li; Zhang, Kai; Locatis, Craig; Ackerman, Michael
2015-05-01
Cloud-based videoconferencing versus traditional systems are described for possible use in telemedicine and distance learning. Differences between traditional and cloud-based videoconferencing systems are examined, and the methods for identifying and testing systems are explained. Findings are presented characterizing the cloud conferencing genre and its attributes versus traditional H.323 conferencing. Because the technology is rapidly evolving and needs to be evaluated in reference to local needs, it is strongly recommended that this or other reviews not be considered substitutes for personal hands-on experience. This review identifies key attributes of the technology that can be used to appraise the relevance of cloud conferencing technology and to determine whether migration from traditional technology to a cloud environment is warranted. An evaluation template is provided for assessing systems appropriateness.
The Cloud Detection and UV Monitoring Experiment (CLUE)
NASA Technical Reports Server (NTRS)
Barbier, L.; Loh, E.; Sokolsky, P.; Streitmatter, R.
2004-01-01
We propose a large-area, low-power instrument to perform CLoud detection and Ultraviolet monitoring, CLUE. CLUE will combine the W detection capabilities of the NIGHTGLOW payload, with an array of infrared sensors to perform cloud slicing measurements. Missions such as EUSO and OWL which seek to measure UHE cosmic-rays at 1W20 eV use the atmosphere as a fluorescence detector. CLUE will provide several important correlated measurements for these missions, including: monitoring the atmospheric W emissions &om 330 - 400 nm, determining the ambient cloud cover during those W measurements (with active LIDAR), measuring the optical depth of the clouds (with an array of narrow band-pass IR sensors), and correlating LIDAR and IR cloud cover measurements. This talk will describe the instrument as we envision it.
Air motion determination by tracking humidity patterns in isentropic layers
NASA Technical Reports Server (NTRS)
Mancuso, R. L.; Hall, D. J.
1975-01-01
Determining air motions by tracking humidity patterns in isentropic layers was investigated. Upper-air rawinsonde data from the NSSL network and from the AVE-II pilot experiment were used to simulate temperature and humidity profile data that will eventually be available from geosynchronous satellites. Polynomial surfaces that move with time were fitted to the mixing-ratio values of the different isentropic layers. The velocity components of the polynomial surfaces are part of the coefficients that are determined in order to give an optimum fitting of the data. In the mid-troposphere, the derived humidity motions were in good agreement with the winds measured by rawinsondes so long as there were few or no clouds and the lapse rate was relatively stable. In the lower troposphere, the humidity motions were unreliable primarily because of nonadiabatic processes and unstable lapse rates. In the upper troposphere, the humidity amounts were too low to be measured with sufficient accuracy to give reliable results. However, it appears that humidity motions could be used to provide mid-tropospheric wind data over large regions of the globe.
Distributed Computing for the Pierre Auger Observatory
NASA Astrophysics Data System (ADS)
Chudoba, J.
2015-12-01
Pierre Auger Observatory operates the largest system of detectors for ultra-high energy cosmic ray measurements. Comparison of theoretical models of interactions with recorded data requires thousands of computing cores for Monte Carlo simulations. Since 2007 distributed resources connected via EGI grid are successfully used. The first and the second versions of production system based on bash scripts and MySQL database were able to submit jobs to all reliable sites supporting Virtual Organization auger. For many years VO auger belongs to top ten of EGI users based on the total used computing time. Migration of the production system to DIRAC interware started in 2014. Pilot jobs improve efficiency of computing jobs and eliminate problems with small and less reliable sites used for the bulk production. The new system has also possibility to use available resources in clouds. Dirac File Catalog replaced LFC for new files, which are organized in datasets defined via metadata. CVMFS is used for software distribution since 2014. In the presentation we give a comparison of the old and the new production system and report the experience on migrating to the new system.