The vertical structure of convective mass-flux derived from modern radar systems - Data analysis in support of cumulus parametrization. Final Report

Abstract Convection strongly influences the distribution of atmospheric trace gases. General circulation models (GCMs) use convective mass fluxes calculated by parameterizations to transport gases, but the results are difficult to compare with trace gas observations because of differences in scale. The high resolution of cloud-resolving models (CRMs) facilitates direct comparison with aircraft observations. Averaged over a sufficient area, CRM results yield a validated product directly comparable to output from a single global model grid column. This study presents comparisons of vertical profiles of convective mass flux and trace gas mixing ratios derived from CRM and single column model (SCM) simulations of storms observed during three field campaigns. In all three cases, SCM simulations underpredicted convective mass flux relative to CRM simulations. As a result, the SCM simulations produced lower trace gas mixing ratios in the upper troposphere in two of the three storms than did the CRM simulations. The impact of parameter sensitivity in the moist physics schemes employed in the SCM has also been examined. Statistical techniques identified the most significant parameters influencing convective transport. Convective mass fluxes are shown to be strongly dependent on chosen parameter values. Results show that altered parameter settings can substantially improve the comparison between SCM and CRM convective mass flux. Upper tropospheric trace gas mixing ratios were also improved in two storms. In the remaining storm, the SCM representation of CO2 was not improved because of differences in entrainment and detrainment levels in the CRM and SCM simulations.

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Seismic Data Analysis Center Final Report

10.21236/ada086802 ◽

1978 ◽

Cited By ~ 1

Author(s):

Robert R. Blandford

Keyword(s):

Data Analysis ◽

Seismic Data ◽

Final Report ◽

Analysis Center

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Evaluation of the convective mass flux profiles associated with cumulus parameterization schemes of CMIP5 models

Journal of Earth System Science ◽

10.1007/s12040-020-01400-5 ◽

2020 ◽

Vol 129 (1) ◽

Author(s):

Parthasarathi Mukhopadhyay ◽

Kumar Roy

Keyword(s):

Mass Flux ◽

Cumulus Parameterization ◽

Cmip5 Models ◽

Parameterization Schemes ◽

Cumulus Parameterization Schemes ◽

Convective Mass Flux

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Issues of representation in narrative methodology in health research

Narrative Inquiry ◽

10.1075/ni.25.2.09med ◽

2015 ◽

Vol 25 (2) ◽

pp. 361-371 ◽

Cited By ~ 1

Author(s):

Priscilla Medeiros

Keyword(s):

Data Analysis ◽

Research Design ◽

Health Research ◽

Collaborative Inquiry ◽

Final Report ◽

Design Data ◽

Dissemination Of Research ◽

Research Findings ◽

Narrative Methodology

Engaging in collaborative inquiry creates a shared authorship in storytelling, but does not ensure that the final report will reflect the plurality of voices that contributed to the narrative. This paper describes how involving respondents in the research design, data analysis, and dissemination of research findings enables researchers to ensure equal representation of perspectives of individuals involved in health research.

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Measuring the variability of the shallow convective mass flux profiles in the tropical trade wind region

10.5194/egusphere-egu2020-4780 ◽

2020 ◽

Author(s):

Marcus Klingebiel ◽

Heike Konow ◽

Bjorn Stevens

Keyword(s):

Boundary Layer ◽

Vertical Velocity ◽

Mass Flux ◽

Doppler Radar ◽

Cloud Fraction ◽

Cloud Base ◽

Trade Wind ◽

Geophysical Research ◽

Wind Region ◽

Convective Mass Flux

Mass flux is a key parameter to represent shallow convection in global circulation models. To estimate the shallow convective mass flux as accurately as possible, observations of this parameter are necessary. Prior studies from Ghate et al. (2011) and Lamer et al. (2015) used Doppler radar measurements over a few months to identify a typical shallow convective mass flux profile based on cloud fraction and vertical velocity. In this study, we extend their observations by using long term remote sensing measurements at the Barbados Cloud Observatory (13&#176; 09&#8217; N, 59&#176; 25&#8217; W) over a time period of 30 months and check a hypothesis by Grant (2001), who proposed that the cloud base mass flux is just proportional to the sub-cloud convective velocity scale. Therefore, we analyze Doppler radar and Doppler lidar measurements to identify the variation of the vertical velocity in the cloud and sub-cloud layer, respectively. Furthermore, we show that the in-cloud mass flux is mainly influenced by the cloud fraction and provide a linear equation, which can be used to roughly calculate the mass flux in the trade wind region based on the cloud fraction.&#160;References: Ghate,&#160; V.&#160; P.,&#160; M.&#160; A.&#160; Miller,&#160; and&#160; L.&#160; DiPretore,&#160; 2011:&#160;&#160; Vertical&#160; velocity structure of marine boundary layer trade wind cumulus clouds. Journal&#160; of&#160; Geophysical&#160; Research: Atmospheres, 116&#160; (D16), doi:10.1029/2010JD015344.Grant,&#160; A.&#160; L.&#160; M.,&#160; 2001:&#160;&#160; Cloud-base&#160; fluxes&#160; in&#160; the&#160; cumulus-capped boundary layer. Quarterly Journal of the Royal Meteorological Society, 127 (572), 407&#8211;421, doi:10.1002/qj.49712757209.Lamer, K., P. Kollias, and L. Nuijens, 2015:&#160; Observations of the variability&#160; of&#160; shallow&#160; trade&#160; wind&#160; cumulus&#160; cloudiness&#160; and&#160; mass&#160; flux. Journal of Geophysical Research: Atmospheres, 120&#160; (12), 6161&#8211;6178, doi:10.1002/2014JD022950.

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Multipath data analysis and exploitation for the design of distributed radar systems

10.1117/12.713943 ◽

2007 ◽

Cited By ~ 1

Author(s):

Atindra K. Mitra ◽

Philip Robinson ◽

James LaRue ◽

John Glett

Keyword(s):

Data Analysis ◽

Radar Systems

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Clouds and hazes vertical structure of a Saturn's giant vortex from Cassini/VIMS-V data analysis

Icarus ◽

10.1016/j.icarus.2016.06.021 ◽

2016 ◽

Vol 278 ◽

pp. 215-237 ◽

Cited By ~ 4

Author(s):

F. Oliva ◽

A. Adriani ◽

M.L. Moriconi ◽

G.L. Liberti ◽

E. D'Aversa ◽

...

Keyword(s):

Data Analysis ◽

Vertical Structure ◽

Giant Vortex

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Spatial Patterns of Precipitation Change in CMIP5: Why the Rich Do Not Get Richer in the Tropics

Journal of Climate ◽

10.1175/jcli-d-12-00543.1 ◽

2013 ◽

Vol 26 (11) ◽

pp. 3803-3822 ◽

Cited By ~ 217

Author(s):

Robin Chadwick ◽

Ian Boutle ◽

Gill Martin

Keyword(s):

Spatial Patterns ◽

Mass Flux ◽

Precipitation Change ◽

Specific Humidity ◽

Tropical Precipitation ◽

Humidity Change ◽

The Rich ◽

Convergence Zones ◽

The Tropics ◽

Convective Mass Flux

Abstract Changes in the patterns of tropical precipitation (P) and circulation are analyzed in Coupled Model Intercomparison Project phase 5 (CMIP5) GCMs under the representative concentration pathway 8.5 (RCP8.5) scenario. A robust weakening of the tropical circulation is seen across models, associated with a divergence feedback that acts to reduce convection most in areas of largest climatological ascent. This is in contrast to the convergence feedback seen in interannual variability of tropical precipitation patterns. The residual pattern of convective mass-flux change is associated with shifts in convergence zones due to mechanisms such as SST gradient change, and this is often locally larger than the weakening due to the divergence feedback. A simple framework is constructed to separate precipitation change into components based on different mechanisms and to relate it directly to circulation change. While the tropical mean increase in precipitation is due to the residual between the positive thermodynamic change due to increased specific humidity and the decreased convective mass flux due to the weakening of the circulation, the spatial patterns of these two components largely cancel each other out. The rich-get-richer mechanism of greatest precipitation increases in ascent regions is almost negated by this cancellation, explaining why the spatial correlation between climatological P and the climate change anomaly ΔP is only 0.2 over the tropics for the CMIP5 multimodel mean. This leaves the spatial pattern of precipitation change to be dominated by the component associated with shifts in convergence zones, both in the multimodel mean and intermodel uncertainty, with the component due to relative humidity change also becoming important over land.

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