Estimates of short-term forecast-temperature error correlations and the implications for radiance-data assimilation

2000 ◽  
Vol 126 (562) ◽  
pp. 361-373
Author(s):  
AP MCNALLY
Keyword(s):  
Data Assimilation ◽  
Temperature Error ◽  
Short Term ◽  
Short Term Forecast ◽  
Term Forecast ◽  
Radiance Data

scholarly journals Evaluation of a Cloud-Scale Lightning Data Assimilation Technique and a 3DVAR Method for the Analysis and Short-Term Forecast of the 29 June 2012 Derecho Event

2014 ◽  
Vol 142 (1) ◽  
pp. 183-202 ◽  
Author(s):  
Alexandre O. Fierro ◽  
Jidong Gao ◽  
Conrad L. Ziegler ◽  
Edward R. Mansell ◽  
Donald R. MacGorman ◽  
...  
Keyword(s):  
Data Assimilation ◽  
Computational Cost ◽  
Mesoscale Convective System ◽  
Radar Reflectivity ◽  
Convective System ◽  
Variational Technique ◽  
Short Term ◽  
Short Term Forecast ◽  
Term Forecast ◽  
Mesoscale Convective

Abstract This work evaluates the short-term forecast (≤6 h) of the 29–30 June 2012 derecho event from the Advanced Research core of the Weather Research and Forecasting Model (WRF-ARW) when using two distinct data assimilation techniques at cloud-resolving scales (3-km horizontal grid). The first technique assimilates total lightning data using a smooth nudging function. The second method is a three-dimensional variational technique (3DVAR) that assimilates radar reflectivity and radial velocity data. A suite of sensitivity experiments revealed that the lightning assimilation was better able to capture the placement and intensity of the derecho up to 6 h of the forecast. All the simulations employing 3DVAR, however, best represented the storm’s radar reflectivity structure at the analysis time. Detailed analysis revealed that a small feature in the velocity field from one of the six selected radars in the original 3DVAR experiment led to the development of spurious convection ahead of the parent mesoscale convective system, which significantly degraded the forecast. Thus, the relatively simple nudging scheme using lightning data complements the more complex variational technique. The much lower computational cost of the lightning scheme may permit its use alongside variational techniques in improving severe weather forecasts on days favorable for the development of outflow-dominated mesoscale convective systems.

scholarly journals The impact of lightning and radar data assimilation on the performance of very short term rainfall forecast for two case studies in Italy

2018 ◽  
Author(s):  
Stefano Federico ◽  
Rosa Claudia Torcasio ◽  
Elenio Avolio ◽  
Olivier Caumont ◽  
Mario Montopoli ◽  
...  
Keyword(s):  
Data Assimilation ◽  
Case Studies ◽  
Radar Reflectivity ◽  
Short Term ◽  
Short Term Forecast ◽  
Term Forecast ◽  
First Case ◽  
Factor Data ◽  
The Impact ◽  
Reflectivity Factor

Abstract. In this paper, we study the impact of lightning and radar reflectivity factor data assimilation on the precipitation VSF (Very Short-term Forecast, 3 hours in this study) for two relevant case studies occurred over Italy. The first case refers to a moderate localised rainfall over Central Italy happened on 16 September 2017. The second case, occurred on 09 and 10 September 2017, was very intense and caused damages in several parts of Italy, while nine people died around Livorno, in Tuscany. The first case study was missed by most operational forecasts over Italy, including that performed by the model used in this paper, while the Livorno case was partially predicted by operational models. We use the RAMS@ISAC model (Regional Atmospheric Modelling System at Institute for Atmospheric Sciences and Climate of the Italian National Research Council), whose 3D-Var extension to the assimilation of RADAR reflectivity factor is shown in this paper. Results for the two cases show that the assimilation of lightning and radar reflectivity factor, especially when used together, have a significant and positive impact on the precipitation forecast. The improvement compared to the control model, not assimilating lightning and radar reflectivity factor, is systematic because occurs for all the Very Short-term Forecast (VSF, 3h) of the events considered. For specific time intervals, the data assimilation is of practical importance for Civil Protection purposes because it transforms a missed forecast of intense precipitation (> 40 mm/3h) in a correct forecast. While there is an improvement of the rainfall VSF thanks to the lightning and radar reflectivity factor data assimilation, its impact is reduced by the increase of the false alarms in the forecast assimilating both types of data.

scholarly journals Assimilation of Flash Extent Data in the Variational Framework at Convection-Allowing Scales: Proof-of-Concept and Evaluation for the Short-Term Forecast of the 24 May 2011 Tornado Outbreak

2016 ◽  
Vol 144 (11) ◽  
pp. 4373-4393 ◽  
Author(s):  
Alexandre O. Fierro ◽  
Jidong Gao ◽  
Conrad L. Ziegler ◽  
Kristin M. Calhoun ◽  
Edward R. Mansell ◽  
...  
Keyword(s):  
Data Assimilation ◽  
Three Dimensional ◽  
Wrf Model ◽  
Radar Data ◽  
Added Value ◽  
Short Term ◽  
Short Term Forecast ◽  
Term Forecast ◽  
Total Lightning ◽  
Tornado Outbreak

Abstract This work evaluates the performance of the assimilation of total lightning data within a three-dimensional variational (3DVAR) framework for the analysis and short-term forecast of the 24 May 2011 tornado outbreak using the Weather Research and Forecasting (WRF) Model at convection-allowing scales. Between the lifted condensation level and a fixed upper height, pseudo-observations for water vapor mass first are created based on either the flash extent densities derived from Oklahoma Lightning Mapping Array data or the lightning source densities derived from the Earth Networks pulse data, and then assimilated by the 3DVAR system. Assimilation of radar data with 3DVAR and a cloud analysis algorithm (RAD) also are performed as a baseline for comparison and in tandem with lightning to evaluate the added value of this lightning data assimilation (LDA) method. Given a scenario wherein the control experiment without radar or lightning data assimilation fails to accurately initiate and forecast the observed storms, the LDA and RAD yield comparable short-term forecast improvements. The RAD alone produces storms of similar strength to the observations during the first 30 min of forecast more rapidly than the LDA alone; however, the LDA is able to better depict individual supercellular features at 1-h forecast. When both the lightning and radar data are assimilated, the 30-min forecast showed noteworthy improvements over RAD in terms of the model’s ability to better resolve individual supercell structures and still maintained a 1-h forecast similar to that from the LDA. The results chiefly illustrate the potential value of assimilating total lightning data along with radar data.

scholarly journals Principal Possibility of the Successful Nowcast and Short-Term Forecast in the Middle Atmosphere Based on the Observed UV Irradiance

2012 ◽  
Vol 2012 ◽  
pp. 1-7
Author(s):  
T. Egorova ◽  
E. Rozanov ◽  
A. V. Shapiro ◽  
W. Schmutz
Keyword(s):  
Climate Model ◽  
Middle Atmosphere ◽  
Satellite Measurements ◽  
Short Term ◽  
Short Term Forecast ◽  
Atmospheric Species ◽  
Term Forecast ◽  
Uv Irradiance ◽  
Solar Uv ◽  
Solar Uv Irradiance

We have applied chemistry-climate model (CCM) SOCOL to simulate the distribution of the temperature and gas species in the upper stratosphere and mesosphere. As an input for the simulation, we employ daily spectral solar UV irradiance measured by SUSIM instrument onboard UARS satellite in January 1992. We have carried out an ensemble of nine 1-month long simulations using slightly different initial states of the atmosphere. We have compared the obtained time evolution of the simulated species and temperature with available satellite measurements. The obtained results allowed us to define the areas where the nowcast and short-term forecast of the atmospheric species with CCM SOCOL could be successful.

scholarly journals Features of the functioning of financial pyramids using digital assets (using the example of the Finico project): criminological analysis

2021 ◽  
Vol 4 ◽  
pp. 104-109
Author(s):  
S. S. Grozin ◽  
◽  
ZH.V. Ostrovskikh ◽  
Keyword(s):  
Performance Indicators ◽  
Digital Technologies ◽  
Short Term ◽  
Short Term Forecast ◽  
Term Forecast ◽  
Criminological Analysis ◽  
Digital Assets

The article deals with the problem of the emergence and functioning of financial pyramids based on the use of digital assets, using the example of the «Finico» project. The main performance indicators are analyzed, as well as the reasons that influenced the success of this project, its scale and duration of existence are characterized. Particular attention is paid to the ways of organizing and carrying out illegal financial activities with signs of financial pyramids, and some measures are proposed to counter it. A short-term forecast of an increase in the number of crimes committed using information, telecommunications and digital technologies in this area is given.

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