Vladimir V. Zuev

Application of MTP-5PE meteorological temperature profiler in an airport for determining spatial zones of possible aircraft Icing

We present the results of applying the MTP-5PE meteorological temperature profiler for determining the spatial zones of possible aircraft icing in Tomsk airport on March 17, 2013. The spatial zones were determined using the RAP-algorithm, the Godske formula, as well as the AMIS-RF data for retrieving the humidity profile. The RAP algorithm and the Godske formula are shown to predict similar locations of spatial zones of possible aircraft icing. However, the RAP results are closer to the actual icing reports available from aircraft crews.

Collision broadening effect upon tropospheric temperature calibration functions for pure rotational Raman lidars

We present the general calibration function for temperature retrievals in the cloud-free troposphere using pure rotational Raman (PRR) lidars under the condition of the laser-beam receiver-field-of-view complete overlap. The function is derived within the framework of the semiclassical theory and takes account of the broadened by collision effects elastic backscattered signal leakage into the nearest (to the laser line) lidar PRR channel. The two simplest nonlinear special cases of the general calibration function are considered to be applied in the temperature retrieval algorithm. The vertical temperature profiles retrieved from nighttime lidar measurements in Tomsk (56.48°N, 85.05°E), on October 2, 2014, are given as an example. The measurements were performed using a PRR lidar designed in Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences (IMCES SB RAS) for lower-atmosphere temperature-profile retrievals.

Some characteristics of inversions in Tomsk according to MTP-5 temperature profiler

Data on temperature inversions in the vicinity of Tomsk on the basis of MTP-5PE profiler data carried out at the IMCES SB RAS were summarized. It is shown that during persistent long-lived powerful anticyclones there is high recurrence of temperature inversions - they occur every day, or 90% of the time. A few characteristics of inversions observed in the region of the Bogashevo airport are presented.

Evaluation of supercooled water content in the atmosphere using real-time radiometry methods

Dynamics and statistics of the total content of supercooled water were studied using real-time radiometry methods in the period from November 2016 to January 2017, when aircraft icing was observed at the Tomsk airport. The histogram of the total water content is single-modal and shifted to the left; and the temperature histogram is bimodal. The minimum and maximum values of the total water content are 0 kg/m2 and 1.5 kg/m2 , respectively; and the minimum and maximum temperatures are – 19° C and 0° C. The bimodality of the temperature histogram represents two combined processes that occur during the supercooled water droplets formation in the considered period. The first process is connected with the change of the season of the year, the second - with the arrival of warm and moist air masses to the cold territory.

On the role of the eruption of the Merapi volcano in an anomalous total ozone decrease over Tomsk in April 2011

In April 2011, at Northern Hemisphere midlatitudes, a long-term anomalous decrease in the total ozone content was recorded over a number of regions, attributed to echoes of a large-scale Arctic ozone anomaly, observed in March. We showed that stratospheric ozone destruction over Tomsk during that period was caused by an eruption of Indonesian volcano Merapi in November, 2010. The NOAA HYSPLIT model was used to analyze air mass transport in the lower stratosphere starting from coordinates of volcanic emission from the date of eruption until late April. It was found that air masses, containing volcanic aerosol, came to the Northern Hemisphere midlatitudes in late March, 2011, in agreement with high aerosol content recorded in the stratosphere over Tomsk during that period. Based on analysis of temperature and ozone anomalies in the stratosphere over Tomsk, these anomalies were shown to be due to the presence of volcanic soot in aerosol composition.

Territorial peculiarities of aircraft icing for Tomsk and Novosibirsk International airports

It is shown that the maximum frequency distribution of icing pireps at the Novosibirsk International Airport in January 2015 was accounted for the height layer from 0 to 1 km. With the increasing height aircraft icing is less common and, starting at 5 km, it is not recorded. Maximum frequency distribution for the Tomsk International Airport in winter 2014 – 2015 was also recorded at these altitudes, but it is not so pronounced, and from 4 km icing has not been reported. Altitude dependencies of frequency distribution for Novosibirsk and Tomsk airports are significantly different from that in the continental United States [1] and from the results published in [2].

Remote sensing of potential aircraft icing areas

Remote sensing technique of detection of potential aircraft icing areas based on temperature profile measurements, using meteorological temperature profiler, and the data of the Airfield Measuring and Information System (AMIS-RF), was proposed, theoretically described and experimentally validated during the field project in 2012 - 2013 in the Tomsk Bogashevo Airport. Spatial areas of potential aircraft icing were determined using the RAP algorithm and Godske formula. The equations for the reconstruction of profiles of relative humidity and dew point using data from AMIS-RF are given. Actual data on the aircraft icing for the Tomsk Bogashevo Airport on 11 October 2012 and 17 March 2013 are presented in this paper. The RAP algorithm and Godske formula show similar results for the location of spatial areas of potential icing. Though, the results obtained using the RAP algorithm are closer to the actual data on the icing known from aircraft crew reports.

Using WRF mesoscale model to restore temperature profile in atmosphere boundary layer in Tomsk

In the paper, the possible use of a WRF mesoscale model for the detailed restoring of a temperature profile in the atmosphere boundary layer (ABL) during winter anticyclone is studied. The correctness of air temperature modeling as well as the possible use of a WRF model for predicting a vertical temperature distribution was shown.

Lidar observation of midlatitude stratospheric aerosols in long-term volcanically quiet period

We analyze the data of measurements of the optical characteristics of stratospheric aerosol layer (SAL), obtained at the Siberian Lidar Station of lAO SB RAS in Tomsk (56°N, 85°E). The data are considered in comparison with results of previous years of observations in Tomsk and at other midlatitude stations of the Northern Hemisphere. The results characterize SAL state in extended volcanically quiet period. The last explosive volcanic eruption was observed in June 1991 (volcano Pinatubo). For the first time such a SAL state is studied using modem ground-based and satellite measurement facilities. The results of observations show that the background levels of the natural aerosols in the stratosphere may be lower than was considered earlier. The anthropogenic growth of background stratospheric aerosol content is not observed. The presence of seasonality and quasi-biennial oscillation (QBO), with a characteristic increase of aerosol content at midlatitudes in periods of intensification of winter-spring meridional transport from tropical belt to midlatitudes and in westerly QBO phases, is an evidence in favor of hypothesis about the presence of tropical reservoir of not only volcanic but also background stratospheric aerosol.

Study of vertical NO 2 and 0 3 distributions in the stratosphere at Siberian Lidar Station (56.5°N, 85.1°E) in the period from 1996 to 2004

The paper presents the results of analysis of regular spectrophotometric and lidar measurements of vertical distribution ozone and nitrogen dioxide content obtained at Siberian Lidar Station of Institute of Atmospheric Optics SB RAS (56.48N/85.05E) from January 1996 to December 2004. The profiles obtained from the results of lidar atmospheric sensing in the altitude range from 25 to 35 km were the initial data for analysis of the vertical ozone distribution. The data on vertical distribution content of nitrogen dioxide in the altitude range from 30 to 35 km were calculated using twilight measurements of the spectral sky brightness along the zenith in the wavelength range from 430 to 450nm.