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Valentin Simeonov

Related publications (34)

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Are atmospheric surface layer f lows ergodic?

Valentin Simeonov, Martin Froidevaux, Marc Parlange, Gabriel George Katul, Chad Higgins

The transposition of atmospheric turbulence statistics from the time domain, as conventionally sampled in field experiments, is explained by the so-called ergodic hypothesis. In micrometeorology, this hypothesis assumes that the time average of a measured ...

American Geophysical Union2013

Raman Lidar for Meteorological Observations, RALMO - Part 1: Instrument description

Hubert van den Bergh, Bertrand Calpini, Valentin Simeonov, Marc Parlange, Pablo Roberto Ristori, Todor Dinoev

A new Raman lidar for unattended, round-the-clock measurement of vertical water vapor profiles for operational use by the MeteoSwiss has been developed during the past years by the Swiss Federal Institute of Technology, Lausanne. The lidar uses narrow fiel ...

European Geosciences Union2013

Raman Lidar for Meteorological Observations, RALMO - Part 2: Validation of water vapor measurements

Bertrand Calpini, Valentin Simeonov

The Raman Lidar for Meteorological Observations (RALMO) was installed at the MeteoSwiss Regional Center of Payerne, Switzerland, in summer 2008. One of its aims is to provide continuous vertical profiles of tropospheric water vapor during day and night at ...

European Geosciences Union2013

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Taylor’s frozen turbulence hypothesis is the central assumption invoked in most experiments designed to investigate turbulence physics with time resolving sensors. It is also frequently used in theoretical discussions when linking Lagrangian to Eulerian fl ...

2012

Line-of-sight data transmission system based on Mid IR quantum cascade laser - art. no. 68770F

Hubert van den Bergh, Valentin Simeonov

We report on an application of a pulsed distributed feedback quantum cascade laser (QCL) for an open path data transmission. A pulse QCL in the 1046 cm(-1) range (28.7 THz) is used as a carrier signal source. The QCL is modulated with 50 ns pulses at repet ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2008

EARLINET: the European Aerosol Lidar Network

Valentin Simeonov, Valentin Mitev

EARLINET, the European Aerosol Research Lidar Network, is the first aerosol lidar network with the main goal to provide a comprehensive, quantitative, and statistically significant database for the aerosol distribution on a continental scale. Lidar measure ...

2006

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Water vapour has been measured from the International Scientific Station Jungfraujoch (ISSJ, 47° N, 7° E, 3580 in above sea level) during the winters of 1999/2000 and 2000/2001 by microwave radiometry and Raman lidar. The abundance of atmospheric water vap ...

Copernicus Publications2004

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We report direct absorption spectroscopic detection of ozone at ambient pressure with a pulsed, DFB quantum-cascade laser (QCL) tuned within 1044-1050 cm(-1) by temperature scanning. Wavelength calibration curves were derived from FTIR and CO2 spectra and ...

Springer-Verlag2004

Elevated atmospheric boundary layer over the Swiss Alps during the August 2003 heat wave

Hubert van den Bergh, Bertrand Calpini, Valentin Simeonov, Marc Parlange, Ioan Balin

An unusual elevated atmospheric boundary layer (ABL) at altitudes of Lip to 5000 m was observed, using a combination of elastic and water vapor lidars, during a 10-day period in 2003. There was a persistent stationary anticyclonic regime over Western Europ ...

Esa Publications Division2004

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This paper concerns an evaluation of ozone (O-3) and planetary boundary layer (PBL) dynamics over the complex topography of the Grenoble region through a combination of measurements and mesoscale model (METPHOMOD) predictions for three days, during July 19 ...

Copernicus Publications2003