The book is a concise guide dealing with the subject of air turbulence and its methods of detection with particular applications to aviation turbulence. It begins with a general description of turbulence and provides a background into the nature and causes of atmospheric turbulence that affect aircraft motion, giving updates on the state-of-the-art research on clear air turbulence (CAT). Important physical processes leading to the Kelvin-Helmholtz instability, a primary producer of CAT, are also explained. The several categories of CAT along with its impact on commercial aviation are also presented in a separate chapter, with particular emphasis on the structural damages to planes and injuries. The central theme of the book deals with both the earlier and the latest CAT detecting methods and techniques for remote and in situ sensing and forecasting. A concise presentation of new technologies for reducing aviation weather-related accidents is also offered. A chapter on the weather accident prevention project of the NASA aviation safety program is also included. Additionally, the book ends with a full description of the recent research activities on CAT and future challenges in turbulence detection, prediction and avoidance.Leonardo Di G. Sigalotti
Author(s): Leonardo Di G. Sigalotti, Fidel Cruz Peregrino, Alejandro Ramírez-Rojas
Publisher: CRC Press/Science Publishers
Year: 2023
Language: English
Pages: 428
City: Boca Raton
Cover
Title Page
Copyright Page
Dedication
Preface
Table of Contents
Part I
1. The Theory of Turbulence
1.1 Introduction
1.2 The Kelvin-Helmholtz instability and the onset of turbulence
1.2.1 The Helmholtz two-layer system
1.2.2 Linear stability theory: discontinuous velocity profiles
1.2.3 The Taylor-Goldstein equation
1.2.4 The Richardson number criterion
1.3 Characteristics of turbulence
1.3.1 Statistical description of turbulence
1.3.2 Spectral analysis of turbulence
1.3.3 Clear air turbulence
1.4 Kolmogorov’s theory
1.4.1 The energy cascade
1.4.2 Kolmogorov’s similarity hypotheses
1.4.3 The energy spectrum of turbulence
1.4.4 The Taylor microscale
1.4.5 Intermittency
2. The Numerical Modeling of Turbulence
2.1 Introduction
2.2 The Navier-Stokes equations
2.2.1 Compressible flows
2.2.2 Incompressible flows
2.2.3 Non-isothermal flows: heat transfer
2.3 Reynolds averaged Navier-Stokes (RANS) equations
2.3.1 Compressible flows
2.3.2 Incompressible flows
2.4 Large eddy simulation (LES) equations
2.4.1 Incompressible flows
2.4.2 Compressible flows
2.4.3 Subgrid scale stresses
2.5 Direct numerical simulations (DNS)
3. Clear Air Turbulence (CAT)
3.1 Introduction
3.2 Definition of CAT
3.3 Dynamical meteorology
3.4 Aviation meteorology
3.4.1 Atmospheric gravity currents
3.4.2 Microbursts
3.4.3 Vertical wind shear and gravity/shear waves
3.4.4 Icing
3.4.5 Terrain-induced atmospheric turbulence
3.4.6 Thunderstorms
3.4.7 Aircraft wake vortices
3.5 Synoptic meteorology
3.6 Aircraft pollution
3.7 Atmospheric gravity waves
3.8 Wind shear
3.9 Jet streams and streaks
3.10 Lee waves and mountain waves
3.11 Temperature gradients
3.12 Vortex rolls
3.13 Lighthill-Ford theory
3.14 Fossil turbulence
3.15 Is CAT increasing?
4. Meteorological Evidence for CAT
4.1 Introduction
4.2 Meteorological analysis of CAT around the tropopause
4.3 The probabilistic structure of CAT
4.4 Relation of CAT with the mesoscale structure of the jet stream region
4.5 Wind and temperature profiles
4.6 Turbulence at low altitudes
Part II
5. Types of Forecasts for Aviation
5.1 Introduction
5.2 High-level SIGWX forecasts
5.3 Mid-level SIGWX forecasts
5.4 Low-level SIGWX forecasts
5.5 Aerodrome or terminal airfield forecasts (TAFs)
5.6 Special forecasts
6. Effects of CAT on Aviation Operations and Aircraft
6.1 Introduction
6.2 Categories and types of air turbulence
6.3 Impact of turbulence on commercial aviation
6.4 Flight diversions and delays
6.5 Structural damage to planes
6.6 Can turbulence cause a plane crash?
6.7 Turbulence injury trends
Part III
7. Earlier Methods of CAT Detection and Warning
7.1 Introduction
7.2 Passive and active acoustics
7.2.1 Passive optical techniques
7.2.1.1 Rayleigh scattering
7.2.1.2 Relative movements of stellar images
7.2.1.3 Atmospheric infrared emission
7.2.1.4 Infrared schlieren optics
7.2.1.5 Ozone detection
7.2.2 Active acoustics
7.2.2.1 Radar detection
7.2.2.2 Doppler acoustic techniques
7.2.2.3 Laser Doppler radars
7.2.2.4 Laser Doppler velocimetry
7.3 Optical stellar scintillation
7.3.1 The refraction theory of scintillation
7.3.2 The diffraction theory of scintillation
7.3.3 Analysis of turbulent fluctuations
7.4 Microwave scintillation of radio stars and satellite beacons
7.4.1 Scintillation theory
7.4.2 Coherence
7.4.3 The advent of satellite beacons
7.5 Infrared and microwave radiometry
7.6 LIDAR
7.6.1 Atmospheric sounding
7.6.1.1 Rayleigh LIDAR
7.6.1.2 Aerosol LIDAR
7.6.1.3 Differential-absorption LIDAR (DIAL)
7.6.1.4 Raman LIDAR
7.6.1.5 Resonance-fluorescence LIDAR
7.6.2 Backscatter
7.7 Tropospheric radio scatter
7.8 Ultrasensitive radars
7.8.1 The monostatic radar equation
7.8.2 The bistatic radar equation
7.8.3 Limitations of radar sensitivity
8. New Technologies for Reducing Aviation Weather-Related Accidents
8.1 Introduction
8.2 Cockpit weather information systems
8.3 First-generation systems
8.4 Weather information presentation
8.5 Next-generation systems
8.6 The route towards enhanced turbulence radars
8.7 Automated turbulence reporting
8.8 Automated airborne weather reporting
8.9 The quasi-common-path method
8.10 Sensor systems
8.11 Weather information communication
9. Modern Methods and Techniques for CAT Detection
9.1 Introduction
9.2 Airborne measurements of turbulence
9.2.1 In-situ measurements
9.2.1.1 Aircraft response to turbulence
9.2.1.2 Aircraft response function
9.2.2 Airborne Doppler interferometry
9.2.3 Other airborne systems for aerosol sensing
9.2.4 Turbulence sensing in clouds and over mountains
9.2.5 Emerging airborne in situ technologies and methods
9.2.5.1 Airborne lasers in multi-sensor systems
9.2.5.2 The multi-purpose airborne sensor Carrier MASC-3
9.2.5.3 The optical particle counters (OPCs) and optical array probes (OAPs)
9.2.5.4 The W-band radar
9.2.5.5 The Stemme S10-VT motor glider for mountain meteorology
9.3 LIDAR systems
9.3.1 LIDAR remote sensors
9.3.2 Modern Doppler LIDAR systems
9.3.3 Airborne ultraviolet (UV) Doppler LIDAR
9.4 The DELICAT airborne LIDAR
9.5 The JAXA airborne LIDAR
9.6 The AWIATOR airborne LIDAR
9.7 The KMW method for CAT forecasting
9.8 The ULTURB algorithm
9.9 The NCAR/NEXRAD turbulence detection algorithm
9.10 Optical airflow meters
9.11 Small unmanned aircraft systems
10. The Weather Accident Prevention Project, Pilot Perspectives, and Other Issues
10.1 Introduction
10.2 The Weather Accident Prevention (WxAP) project
10.3 Professional pilot perspectives
10.4 Inadequacies of current weather information systems
10.5 Cognitive task analysis
10.6 Weather avoidance doctrine
11. Recent Investigations on CAT and Major Challenges
11.1 Introduction
11.2 Recent CAT research studies
11.2.1 CAT response to climate change
11.2.2 Tropopause folding
11.2.3 Multi-index prediction of CAT based on machine learning
11.2.4 Experimenting a CAT index from the IFS system
11.3 Recent improvements in turbulence forecasting
11.3.1 The World Area Forecast System (WAFS)
11.3.2 ECMWF IFS forecast of severe CAT
11.3.3 Machine learning CAT forecasting based on regression trees
11.3.4 The T2-Net turbulence forecasting
11.4 Future research and needs
11.5 Major challenges in aviation turbulence
References
Index
