Long-term changes in average annual temperature within the atmospheric boundary layer over Siberia

2021 ◽  
Author(s):  
Natalia Y. Lomakina ◽  
A. V. Lavrinenko
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Average Annual Temperature ◽  
Long Term Changes

scholarly journals Finescale Clusterization Intermittency of Turbulence in the Atmospheric Boundary Layer

2020 ◽  
Vol 77 (7) ◽  
pp. 2375-2392
Author(s):  
Lei Liu ◽  
Fei Hu
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Return Time ◽  
Statistical Simulation ◽  
Convective Boundary ◽  
Wind Speeds ◽  
Stable Conditions ◽  
Telegraphic Approximation ◽  
Better Than

AbstractThe intermittency of atmospheric turbulence plays an important role in the understanding of particle dispersal in the atmospheric boundary layer and in the statistical simulation of high-frequency wind speed in various applications. There are two kinds of intermittency, namely, the magnitude intermittency (MI) related to non-Gaussianity and the less studied clusterization intermittency (CI) related to long-term correlation. In this paper, we use a 20 Hz ultrasonic dataset lasting for 1 month to study CI of turbulent velocity fluctuations at different scales. Basing on the analysis of return-time distribution of telegraphic approximation series, we propose to use the shape parameter of the Weibull distribution to measure CI. Observations of this parameter show that contrary to MI, CI tends to weaken as the scale increases. Besides, significant diurnal variations, showing that CI tends to strengthen during the daytime (under unstable conditions) and weaken during the nighttime (under stable conditions), are found at different observation heights. In the convective boundary layer, the mixed-layer similarity is found to scale the CI exponent better than the Monin–Obukhov similarity. At night, CI is found to vary less with height in the regime with large mean wind speeds than in the regime with small mean wind speeds, according to the hockey-stick theory.

Long-term measurements of refractive index structure constant in atmospheric boundary layer

2012 ◽  
Author(s):  
Otakar Jicha ◽  
Pavel Pechac ◽  
Stanislav Zvanovec ◽  
Martin Grabner ◽  
Vaclav Kvicera
Keyword(s):  
Boundary Layer ◽  
Refractive Index ◽  
Atmospheric Boundary Layer ◽  
Structure Constant ◽  
Index Structure

scholarly journals High-altitude Inflatable Kites and Their Role in Atmospheric Boundary Layer Research

2021 ◽  
pp. 1-13
Author(s):  
Michael J. Irvin
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
High Altitude ◽  
Weather Forecasting ◽  
Evolutionary Development ◽  
State University ◽  
Oklahoma State University ◽  
Atmospheric Research ◽  
Aerial Systems

AbstractKites have been used as weather sensing solutions for over 250 years. The fact that they are simpler to operate and train on than alternative aerial systems, their ability to keep station at a fixed point for a long term, simplified altitude control, and the ease of retrieving their payload attribute to their growing appeal in atmospheric research. NASA, Toyota, and the School of Mechanical and Aerospace Engineering Oklahoma State University are active in developing and deploying high-altitude inflatable kite systems for atmospheric boundary layer (ABL) research—crucial to advancing the accuracy of weather forecasting. Improvements in kite design, as well as instrumentation and supporting infrastructure, are key to further accelerating the use of kites in atmospheric research. The work underway by these researchers is intended to be a deliberate step in the evolutionary development of these beneficial systems.

scholarly journals Mount Kenya Global Atmosphere Watch Station (MKN): Installation and Meteorological Characterization

2008 ◽  
Vol 47 (11) ◽  
pp. 2946-2962 ◽  
Author(s):  
Stephan Henne ◽  
Wolfgang Junkermann ◽  
Josiah M. Kariuki ◽  
John Aseyo ◽  
Jörg Klausen
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Convective Boundary Layer ◽  
Atmospheric Composition ◽  
Specific Humidity ◽  
Convective Boundary ◽  
Thermally Induced ◽  
Air Masses ◽  
Downslope Wind

Abstract The meteorological conditions at the Mount Kenya (station identifier MKN) tropical Global Atmosphere Watch Programme station are described. Like other stations in mountainous terrain, the site experiences thermally induced wind systems that disturb free tropospheric conditions. Therefore, the adequacy of the site for long-term background atmospheric composition measurements needs to be evaluated. Meteorological parameters for the period June 2002–June 2006 were analyzed, focusing on the development of thermally induced wind systems and boundary layer influence. Filters based on the local wind and day–night differences in specific humidity were developed for selection of times representative of undisturbed free tropospheric conditions. In addition, the convective boundary layer depth was evaluated. Throughout the whole year the station is influenced by thermally induced wind systems and the atmospheric boundary layer. The filters distinguished between thermally and synoptically influenced days. Thermally influenced days (86%) dominated. However, maxima in specific humidity were also reached in the afternoon on synoptically influenced days and were attributed to mixing in the convective boundary layer. During nighttime, downslope wind dominated that carries undisturbed free tropospheric air masses. Nevertheless, during 24% of all nights the specific humidity was also elevated, possibly indicating the presence of residual layers. It is recommended that nighttime data only (2100–0400 UTC) be used for analysis of long-term trends of the free tropospheric background while the remaining data can be used to characterize composition and trends of the regional atmospheric boundary layer. Further exclusion of apparent pollution events and residual layer influence should be considered. With these constraints, the Mount Kenya Global Atmosphere Watch site is adequate for the study of trends and budgets of background atmospheric composition.

Other Models: Data-Driven Approaches for Non-Stationary Non-Synoptic Winds

2020 ◽  
Author(s):  
Dae Kun Kwon ◽  
Ahsan Kareem
Keyword(s):  
Boundary Layer ◽  
Wind Speed ◽  
Atmospheric Boundary Layer ◽  
Modeling And Simulation ◽  
Data Driven ◽  
Monitoring Systems ◽  
Massive Datasets ◽  
Rapid Advance ◽  
Data Driven Approach

In comparison with atmospheric boundary layer winds, which are generally regarded as stationary, windstorms such as hurricanes, typhoons, and cyclones; thunderstorms and downbursts; and tornadoes generally exhibit non-stationary features characterized by changes in wind speed and direction. Due to these characteristics, it is usually challenging to model them in a simplistic format. To overcome this difficulty, a data-driven approach may be an alternative, one that has gained significant popularity in many fields mainly due to the rapid advance in measurement and monitoring systems that allows the collection of long-term massive datasets. This chapter reviews data-driven approaches employed in the fields of non-stationary non-synoptic winds from their characterization, modeling, and simulation perspectives.

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