104,111 research outputs found
Limited Area Numerical Weather Prediction
No full textTwo limited area model derivatives of the numerical weather prediction model COSMO-DE operated by the German Meteorological Service are introduced. The aim is to obtain frequently updated highly re-solved predictions in a limited area as an aerodrome. The predictions include dynamic parameters as wind and turbulence kinetic energy and thermodynamic quantities as temperature and humidity but also the amount of snow, rain and hail. The models are used in the airport environments of Frankfurt (COSMO-FRA) and Munich (COSMO-MUC) for aircraft wake vortex, thunderstorm activity, and wintry weather warning applications, as detailed in Sections 2.1 to 2.4
Recensione a M. Scheler, La posizione dell'uomo nel cosmo, traduzione dall'edizione originale del 1928, a cura di G. Cusinato, Franco Angeli, Milano 2000
No full textRecensione a M. Scheler, La posizione dell'uomo nel cosmo, traduzione dall'edizione originale del 1928, a cura di G. Cusinato, Franco Angeli, Milano 200
Collision Avoidance Activities for COSMO-SkyMed Constellation
No full textCOSMO-SkyMed (COnstellation of Satellites for Mediterranean basin Observation) is an Earth Observation space program funded by the Italian Ministry of Research and Ministry of Defence and
managed by the Italian Space Agency (ASI) in conjunction with Italian MoD.
COSMO-SkyMed (CSK) consists of a constellation of four Low Earth Orbit mid-sized satellites, each carrying a multi-mode, high resolution, electronically steerable Synthetic Aperture Radar (SAR)
instrument operating at X-band and a full featured Ground Segment to properly exploit space capabilities. CSK System is fully qualified and now in operative phase.
This paper describes the characteristics and functionalities of COSMO-SkyMed collision avoidance system, highlighting its versatility and effectiveness for constellation in flight operations. Moreover, the application of the COSMO-SkyMed risk mitigation daily procedure during two year of operations is described
The COSmic Monopole Observer (COSMO)
No full textThe COSmic Monopole Observer (COSMO) is an experiment to measure low-level spectral distortions in the isotropic component of the Cosmic Microwave Background (CMB). Deviations from a pure blackbody spectrum are expected at low level (< 1 ppm) due to several astrophysical and cosmological phenomena, and promise to provide important independent information on the early and late phases of the universe. They have not been detected yet, due to the extreme accuracy required, the best upper limits being still those from the COBE-FIRAS mission. COSMO is based on a cryogenic differential Fourier Transform Spectrometer, measuring the spectral brightness difference between the sky and an accurate cryogenic blackbody. The first implementation of COSMO, funded by the Italian PRIN and PNRA programs, will operate from the Concordia station at Dome-C, in Antarctica, and will take advantage of a fast sky-dip technique to get rid of atmospheric emission and its fluctuations, separating them from the monopole component of the sky brightness. Here we describe the instrument design, its capabilities, the current status. We also discuss its subsequent implementation in a balloon-flight, which has been studied within the COSMOS program of the Italian Space Agency
Evaluating Ice Microphysics in NWP Models with Satellite Observations
No full textIce clouds are an important part of the Earth’s atmospheric water cycle and have a large impact on the global radiation budget. Yet ice clouds are still poorly understood and their correct representation remains a major challenge for state-of-the-art atmospheric models. Also, the evaluation of the models’ performance with respect to ice clouds is not straightforward; remote sensing instruments, for example, measure other quantities than the models predict. Therefore, two basic evaluation approaches exist: observation-to-model (commonly termed retrieval) and model-to-observation (commonly termed forward operator). Both approaches introduce errors into the comparison of models and observations because of the necessary intrinsic assumptions. The common practice in model evaluation of choosing either the one or the other of these approaches might give an incomplete picture.
The present study evaluates the ice microphysics of two numerical weather prediction (NWP) models currently operational at the German weather service (Deutscher Wetterdienst, DWD): the global model GME and the regional model COSMO-DE (an application of the Consortium for Small-scale Modelling, COSMO). In doing so, this study contributes significantly to ongoing model development at DWD. Both case studies and long-term evaluations are carried out. Cloud Satellite (CloudSat) Cloud Profiling Radar (CPR) observations are heavily relied on; the CPR is the first and — up to date — only cloud radar in space and is able to vertically resolve even optically thick clouds. This study focuses on one specific question raised for each of the respective models and while doing so applies both approaches; the standard CloudSat radar reflectivity factor–ice water content (IWC) retrieval for the observation-to-model approach and the forward operator QuickBeam for the model-to-observation approach. This enables for one, to profit from the full informational content, and for the other, to compare both approaches directly to each other and evaluate them.
For the global model GME, two precipitation schemes, a diagnostic and a prognostic one, are compared and evaluated. The focus is on the question whether the new prognostic scheme is capable of capturing ice clouds more realistically than the old diagnostic scheme. The prognostic scheme is shown to exhibit improved performance in comparison to the diagnostic scheme in terms of IWC magnitude. In both models snow is found to dominate over cloud ice in total IWC, emphasizing the need for including snow in the model’s radiation budget in the future. Furthermore, one reason for the remaining difference between the prognostic scheme and the observations — the unrealistic fall speed of snow — is identified. As a consequence, the new prognostic scheme with an adapted parameterization for snow fall speed was successfully introduced into operational service at DWD.
In the regional NWP model COSMO-DE, a long-known bias between brightness temperatures simulated from COSMO-DE forecasts and those observed by Meteosat Second Generation (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI) is investigated. The pivotal question is whether a novel two-moment cloud ice scheme exhibits improved
performance with respect to this bias and, if that is so, why. It is shown that the novel two-moment cloud ice scheme does indeed reduce this bias and can therefore be considered an improvement in comparison to two standard schemes, the two-category ice scheme and the currently operational three-category ice scheme. The improvement in simulated brightness temperatures is due to a vertical redistribution of cloud ice to lower model levels. Furthermore, sensitivity studies identify two of the four changes introduced, which are responsible for most of the improved performance: the change to a different heterogeneous nucleation scheme and the inclusion of cloud ice sedimentation. Enhanced vertical level number and modifications in aerosol number concentrations reveal comparatively little effect. As a consequence, cloud ice sedimention will be included per se in DWD’s future NWP model, the Icosahedral non-hydrostatic (ICON) model, currently still under development.
Concerning the two evaluation approaches conducted, the present study finds the general features in the two evaluations to be captured by both approaches. Some details are captured merely by the one or the other approach, in which case both approaches together give the more complete picture. However, the model-to-observation approach appears to be easier to interpret; its uncertainties are easier to assess than those of the observation-to-model approach and it ensures a better control over the comparison
Calculation of solvent shifts on electronic g-tensors with the conductor-like screening model (COSMO) and its self-consistent generalization to real solvents (Direct COSMO-RS)
No full textThe conductor-like screening model (COSMO) was used to investigate the solvent influence on electronic g-values of organic radicals. The previously studied diphenyl nitric oxide and di-tert-butyl nitric oxide radicals were taken as test cases. The calculations employed spin-unrestricted density functional theory and the BP and B3LYP density functionals. The g-tensors were calculated as mixed second derivative properties with respect to the external magnetic field and the electron magnetic moment. The first-order response of the Kohn−Sham orbitals with respect to the external magnetic field was determined through the coupled-perturbed DFT approach. The spin−orbit coupling operator was treated using an accurate multicenter spin−orbit mean-field (SOMF) approach. Provided that important hydrogen bonds are explicitly modeled by a supermolecule approach and that the basis set is sufficiently saturated, the COSMO calculations lead to accurate predictions of isotropic g-shifts with deviations of not more than 100 ppm relative to experiment. Very accurate results were obtained by employing a recently developed self-consistent modification of the COSMO method to real solvents (COSMO-RS), which we briefly introduce in this paper as direct COSMO-RS (D-COSMO-RS). This model gives isotropic g-shifts of similar high accuracy for water without using the supermolecule approach. This is an important result because it solves many of the problems associated with the supermolecule approach such as local minima and the choice of a suitable model system. Thus, the self-consistent D-COSMO-RS incorporates some specific solvation effects into continuum models, in particular it appears to successfully model the effects of hydrogen bonding. Although not yet widely validated, this opens a novel approach for the calculation of properties which so far only could be calculated by the inclusion of explicit solvent molecules in continuum solvation methods
Is sedation for endoscopy as safe as you think?
No full text1118 Minerva Anestesiologica N November 2017
I
n this issue of Minerva Anestesiologica, Brumby et al.8 report an observational pilot study assessing the incidence of failure to recover at day 1 and in subsequent days and weeks after either colonoscopy, gastroscopy, or both procedures combined in 102 patients of over the age of 18 years. Recovery was evaluated not only using physiologic endpoints but also evaluating other aspects such as nociception, emotion, activities of daily living (ADL), and cognition on the following day as well as over a 1-month follow-up period using the multidimensional Postoperative Quality of Recovery Scale (PostopQRS ). All the patients received total intravenous anesthesia with propofol alone or in combination with opioids. Some participants received midazolam or opioids in the pre-operative period. The authors have seen that incomplete recovery is common after colonoscopy, gastroscopy or both procedures. Failure to recover was mainly due to failure in nociceptive and cognitive recovery at day 1 with modest but clinically important differences in early quality of recovery between the procedures.
C
orrectly, the authors underline that recovery after endoscopic procedures should be defined by a multidimensional tool able to assess emotive, functional and cognitive domains.
T
his is particularly important because the patients must be discharged as soon as possible and should return to preoperative levels of independency in activities of daily living.
Anesthesia demand for colonoscopy and gastroscopy is increasing each year and this is due to need of diagnostic or screening programs and therapeutic management of acute pathologies or neoplastic diseases. Because of the air or CO 2 insufflation for adequate distention and visualization of the gastrointestinal lumen, the endoscopic procedures are associated with significant pain and discomfort, therefore sedation is often required to improve patient tolerance and safety.1, 2 Propofol alone or combined with midazolam and opioids is commonly used for sedation although drugs as etomidate and dexmedetomidine have been introduced.3, 4 Usually, the procedures are ambulatory and the patients must be discharged soon after the endoscopy. Adverse events during sedation for endoscopy are very low and anesthetic techniques are performed to provide sedation minimizing hemodynamic changes and allowing faster emergence and patient’s discharge. Patients can return to their daily lives safely and promptly as soon as have recovered to pre-procedural baseline physical performance.5 However, optimal recovery after sedation for endoscopy is not always observed.
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ommonly, a patient’s discharge is related to recovery time, adverse events and physiological parameters such as level of consciousness and stability of vital signs.6, 7
EDITORIAL
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s sedation for endoscopy as safe as you think?
Germano DE COS MO 1 *, Elisabetta CONGEDO 2
1Department of Anesthesia and Intensive Care, Sacro Cuore Catholic University, Rome, Italy; 2Department of Anesthesia and Intensive Care, Antonio Perrino Hospital, Brindisi, Italy
*Corresponding author: Germano De Cosmo, Department of Anesthesia and Intensive Care, Sacro Cuore Catholic University, via G. Moscati 31, 00168 Rome, Italy. E-mail: [email protected]
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omment on p. 1161.
Minerva Anestesiologica 2017 November;83(11):1118-20
DOI : 10.23736/S0375-9393.17.12260-1
© 2017 EDIZIONI MINERVA INERVAINERVA MEDICA
O
nline version at http://www.minervamedica.it
COPYRIGHT© 2017 EDIZIONI MINERVA MEDICA
This document is protected by international copyright laws. No additional reproduction is authorized. It is permitted for personal use to download and save only one file and print only one copy of this Article. It is not permitted to make additional copies
(either sporadically or systematically, either printed or electronic) of the Article for any purpose. It is not permitted to distribute the electronic copy of the article through online internet and/or intranet file sharing systems, electronic mailing or any other
means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
not permitted. It is not permitted to remove, cover, overlay, obscure, block, or change any copyright notices or terms of use which the Publisher may post on the Article. It is not permitted to frame or use framing techniques to enclose any trademark, logo,
or other proprietary information of the Publisher.
SA
FET Y OF SE DATIONATION FOR EN DOSCO PY DE COS MO
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ol. 83 - No. 11 Minerva Anestesiologica 1119sedated with propofol or remifentanil.14 Allen et al. have shown that the incidence of post-procedural cognitive impairment was similar in patients randomized to light versus deep sedation. In addition, the authors have not considered pain an important risk factor for post procedural cognitive dysfunction, especially if the endoscopic procedure is diagnostic and not operative.16
S
harma et al. have investigated cognitive function in 108 patients with cirrhosis undergoing endoscopy under sedation with propofol. Before and two hours after endoscopy psychometric tests have been administered to evaluate cognitive function. The authors have not found a worsening of the psychometric tests after the endoscopy.17
T
hese differences can be due to several factors: the type and sensitivity of the psychometric tests used, the variation also in the healthy subjects’ performance at a few days away, the too small simple size. There is a wide confidence interval of evaluated parameters that indicates that there is a great variation of response in the various subjects, due to a small simple size.18-20
I
n conclusion, thousands of endoscopic procedures are performed daily and the main question that this article raises is to understand what means recovery from a procedure: an adequate recovering goes beyond vital functions. Incomplete recovery can last up to one month and is mainly due to nociceptive and cognitive impairment that could also occur in young people undergoing minor procedures. Therefore, subsequent studies might need to investigate if and how a low impact procedure can induce cognitive impairment and the main parameters that should be assessed to consider a patient overall recovered utilizing appropriate tests that can identify the most vulnerable patients.
References
1. A Allen ML. Safety of deep sedation in the endoscopy suite. Curr Opin Anaesthesiol 2017;30:501-6.
2. L Leslie K, Allen ML, Hessian EC , Peyton PJ, Kasza J, Courtney A, et al. Safety of sedation for gastrointestinal
I
n literature, the reported incidence of Postoperative Cognitive Dysfunction (POC D) varies from 20% to 60% between 6 weeks to 3 months after surgery and the causes of this variability are related to type of surgery, duration, patient’s age and cultural level.9
T
he prevalence of POC D has primarily been studied in elderly patients undergoing cardiac surgery.10 However, its frequency should be very rare after endoscopic procedure especially in young people because stress associated to endoscopic procedures is very low as well as the increase of pro-inflammatory cytokines that play a pivotal role in cognitive dysfunction.11, 12
T
he novelty of the study by Brumby et al. is that the people enrolled are young, without risk factors for postoperative cognitive dysfunction, and not undergoing major surgery.
S
urprisingly, a not negligible percentage of patients had a cognitive impairment not only in the early post-procedural period but until one month and perhaps for a longer time if follow-up period would be prolonged. Patients in the gastroscopy group have a lower frequency of overall recovery.
We have to consider that both endoscopic procedures have affected not only cognitive function but also pain. Authors do not report if there is a correlation between POC D and the presence of pain despite they have seen that patients undergoing combined procedures had more pain over the entire 1-month follow-up period and a more cognitive impairment at day 1 than participants having only colonoscopy.
However, these results should be observed with caution not only because endoscopic procedures have been considered with little impact on daily physiological activity and on cognitive and nociceptive domain but also because few studies have been performed, and only for few days.13-15 Moreover, the studies performed give different results.
T
heodorou et al. have demonstrated cognitive impairment up to 120 minutes after propofol/midazolam/fentanyl or nitrous oxide/sevoflurane sedation for colonoscopy.13 Instead, Moerman et al. have not found cognitive dysfunction
after 15 min in colonoscopy patients
COPYRIGHT© 2017 EDIZIONI MINERVA MEDICA
This document is protected by international copyright laws. No additional reproduction is authorized. It is permitted for personal use to download and save only one file and print only one copy of this Article. It is not permitted to make additional copies
(either sporadically or systematically, either printed or electronic) of the Article for any purpose. It is not permitted to distribute the electronic copy of the article through online internet and/or intranet file sharing systems, electronic mailing or any other
means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
not permitted. It is not permitted to remove, cover, overlay, obscure, block, or change any copyright notices or terms of use which the Publisher may post on the Article. It is not permitted to frame or use framing techniques to enclose any trademark, logo,
or other proprietary information of the Publisher.
DE COS MO SA SA FET Y OF SE DATIONATION FOR EN DOSCO PY
1120 Minerva Anestesiologica N November 2017gedo E, De Cosmo G. Cognitive Dysfunction after Surgery: An Emergent Problem. J Alzheimers Dis Parkinsonism 2017;7:1.
13. T Theodorou T, Hales P, Gillespie P, Robertson B. Total intravenous versus inhalational anaesthesia for colonoscopy: a prospective study of clinical recovery and psychomotor function. Anaesth Intensive Care 2001;29:124-36.
14. Moerman ATAT, Foubert LA , Herregods LL , Struys MM, De Wolf DJ, De Looze DA, et al. Propofol versus remifentanil for monitored anaesthesia care during colonoscopy. Eur J Anaesthesiol 2003;20:461-6.
15. Fredman B, Lahav M, Zohar E, Golod M, Paruta I, Jedeikin R. The effect of midazolam premedication on mental and psychomotor recovery in geriatric patients undergoing brief surgical procedures. Anesth Analg 1999;89:1161-6.
16. A Allen M, Leslie K, Hebbard G, Jones I, Mettho T, Maruff P. A randomized controlled trial of ligh versus deep propofol sedation for elective outpatient colonoscopy: recall, procedural condition and recovery. Can J Anesth 2015;62:1169-78.
17. S Sharma P, Singh S, Sharma BC, Kumar M, Garg H, Kumar A, et al. Propofol sedation during endoscopy in patients with cirrhosis, and utility of psychometric tests and critical flicker frequency in assessment of recovery from sedation. Endoscopy 2011;43:400-5.
18. S tark PA, Myles PS, Burke JA. Development and psychometric evaluation of a postoperative quality of recovery score: the QoR-15. Anesthesiology 2013; 118:1332-40.
19. Bowyer AJ, Royse CF. Postoperative recovery and outcomes--what are we measuring and for whom? Anaesthesia 2016;71(Suppl 1):72-7.
20. N Newman S, Wilkinson DJ, Royse CF. Assessment of early cognitive recovery after surgery using the Post-operative Quality of Recovery Scale. Acta Anaesthesiol Scand 2014;58:185-91.
endoscopy in a group of university-affiliated hospitals: a prospective cohort study. Br J Anaesth 2017;118:90-9.
3. Padmanabhan U, Leslie K. Australian anaesthetists’ practice of sedation for gastrointestinal endoscopy in adult patients. Anaesth Intensive Care 2008;36:436-41.
4. Davy A, Fessler J, Fischler M, le Guen M. Dexmedetomidine and general anesthesia: a narrative literature review of its major indications for use in adults undergoing non-cardiac surgery. Minerva Anestesiol 2017 Jun 22. [Epub ahead of print]
5. L Leung FW. Trend in use of sedation for low-risk endoscopy. Looking beyond monitored anesthesis care. JAMA 2017;317:2006-7.
6. Feldman LS , Lee L, Fiore J Jr. What outcomes are important in the assessment of Enhanced Recovery After Surgery (ERAS ) pathways? Can J Anaesth 2015;62:120-30.
7. L Lee L, Tran T, Mayo NE , Carli F, Feldman LS . What does it really mean to “recover” from an operation? Surgery 2014;155:211-6.
8. Brumby AM, Heiberg J, Te C, Royse CF. Quality of recovery after gastroscopy, colonoscopy or both endoscopic procedures: an observational pilot study. Minerva Anestesiol 2017;83:1161-8.
9. R Royse CF, Andrews DT, Newman SN , Stygall J, Williams Z, Pang J, et al. The influence of propofol or desflurane on postoperative cognitive dysfunction in patients undergoing coronary artery bypass surgery. Anaesthesia 2011;66:455-64.
10. N Newman MF, Mathew JP, Grocott HP, Mackensen GB, Monk T, Welsh-Bohmer KA, et al. Central nervous system injury associated with cardiac surgery. Lancet 2006;368:694-703.
11. De Cosmo G, Sessa F, Fiorini F, Congedo E. Effect of remifentanil and fentanyl on postoperative cognitive function and cytokines level in elderly patients undergoing major abdominal surgery. J Clin Anesth 2016;35:40-6.
12. C Canistro G, Levantesi L, Oggiano M, Sicuranza R, ConConflicts
of interest.—The authors certify that there is no conflict of interest with any financial organization regarding the material discussed in the manuscript.
Article first published online: July 12, 2017. - Manuscript accepted: July 5, 2017. - Manuscript received: June 27, 2017.
(Cite this article as: De Cosmo G, Congedo E. Is sedation for endoscopy as safe as you think? Minerva Anestesiol 2017;83:1118-20. DOI : 10.23736/S0375-9393.17.12260-1)
COPYRIGHT© 2017 EDIZIONI MINERVA MEDICA
This document is protected by international copyright laws. No additional reproduction is authorized. It is permitted for personal use to download and save only one file and print only one copy of this Article. It is not permitted to make additional copies
(either sporadically or systematically, either printed or electronic) of the Article for any purpose. It is not permitted to distribute the electronic copy of the article through online internet and/or intranet file sharing systems, electronic mailing or any other
means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
not permitted. It is not permitted to remove, cover, overlay, obscure, block, or change any copyright notices or terms of use which the Publisher may post on the Article. It is not permitted to frame or use framing techniques to enclose any trademark, logo,
or other proprietary information of the Publisher
Dall'armonia del cosmo alla legge
No full textIl concetto dell’armonia del cosmo, nella sua valenza di modello etico di comportamento, può essere assunto a interpretare lo sviluppo del rapporto unitario tra ethos e natura, affermatosi storicamente a sua volta grazie al comporsi in unità di due diversi concetti di natura (quello platonico e quello aristotelico), che trovarono la possibilità di integrarsi grazie alla loro convergenza in un’unica prospettiva fisico-teologica. Tolomeo mostra concretamente questo aspetto di unità, realizzato nella sua concezione cosmologica, nella quale l’ordine del cielo contemplato dall’astronomo diviene così anche paradigma della vita etica. Dopo la lunga fase di apparente estremo rafforzamento, interpretata dal neoplatonismo ed in particolare da Proclo, l’unità fa ethos e natura, ed il concetto stesso che era giunto ad esprimerla, entrano in crisi nel momento nel quale, con la rivoluzione scientifica in ambito cosmologico, l’ordine e la regolarità del cielo e dell’intera natura non possono più essere interpretatati a partire da un principio teologico, ma sulla base del riferimento ad una legge intrinsecamente presente nella natura stessa. L’affermarsi del ruolo della legge, cosi concepita, è manifestato caratteristicamente nel primo sviluppo della modernità da Copernico e Galileo, ma con più nitida consapevolezza concettuale da Decartes. Kant, e l’abisso che nel suo pensiero si scava fra l’ambito della natura e quello dell’ethos in quanto governati da leggi potenzialmente antinomiche, può essere considerato l’espressione in qualche modo conclusiva di questo processo: ma ciò anzitutto in quanto egli si propone come interprete consapevole del significato metafisico della “rivoluzione copernicana”
On the compressibility of large-scale source code datasets
No full textStoring ultra-large amounts of unstructured data (often called objects or blobs) is a fundamental task for several object-based storage engines, data warehouses, data-lake systems, and key–value stores. These systems cannot currently leverage similarities between objects, which could be vital in improving their space and time performance. An important use case in which we can expect the objects to be highly similar is the storage of large-scale versioned source code datasets, such as the Software Heritage Archive (Di Cosmo and Zacchiroli, 2017). This use case is particularly interesting given the extraordinary size (1.5 PiB), the variegated nature, and the high repetitiveness of the at-issue corpus. In this paper we discuss and experiment with content- and context-based compression techniques for source-code collections that tailor known and novel tools to this setting in combination with state-of-the-art general-purpose compressors and the information coming from the Software Heritage Graph. We experiment with our compressors over a random sample of the entire corpus, and four large samples of source code files written in different popular languages: C/C++, Java, JavaScript, and Python. We also consider two scenarios of usage for our compressors, called Backup and File-Access scenario, where the latter adds to the former the support for single file retrieval. As a net result, our experiments show (i) how much “compressible” each language is, (ii) which content- or context-based techniques compress better and are faster to (de)compress by possibly supporting individual file access, and (iii) the ultimate compressed size that, according to our estimate, our best solution could achieve in storing all the source code written in these languages and available in the Software Heritage Archive: namely, in 3 TiB (down from their original 78 TiB total size, with an average compression ratio of 4%)
Validating precipitation forecasts using remote sensor synergy: A case study approach
No full textSeveral types of remote sensing data are applied synergistically to evaluate the chain of microphysical
processes leading to precipitation in a high-resolution numerical weather prediction model. The data provides
information relating to (i) cloud-top temperature and optical depth (SEVERI), (ii) ice cloud amount (AMSUB),
(iii) type and amount of precipitation particles (polarimetric radar), and (iv) surface precipitation
(raingauge-calibrated radar data). Forecasts are produced by the COSMO-DE model of the German weather
service, with a horizontal resolution of 2.8 km. The comparison with data is done in a model-to-observation
framework, that is, forward operators are applied to the model output to produce synthetic data sets that
can be directly compared to the observations. Additional diagnostics based on diurnal cycle and system
tracking are also considered. Two case studies over Germany from the summer of 2006 are examined. The
first case is dominated by widespread stratiform precipitation. Together the various data sets show that the
model overestimates the amount of high cloud, while underestimating the concentration of ice scatterers
and overestimating reflectivity and differential reflectivity (ZDR). This indicates errors in both the amount
and the size distributions of cloud and precipitation particles in the model’s microphysical parameterization.
In the second case a narrow band of convective precipitation is embedded in a cold front, with significant
modulation by the diurnal cycle. The model fails to show a significant diurnal cycle in cloud amount, and
the timing and duration of convective cells is incorrect. In this case, both the microphysical parameterization,
and errors in the interaction of the simulated front with the orography of the Alps appear to contribute. These
results demonstrate the potential of combinations of remote sensing data for model evaluation, although a
long-term trial will be required to determine whether the errors seen in the case studies are characteristic for
COSMO-DE
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