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Visual C#® 2005: How to Program, Second Edition :

Beginning Visual C# 2005 : (Book is in CHM format ) Free (UPDATED) * Offers a highly structured tutorial that's packed with thorough examples and updated code, as well as exercises that help readers test and fine-tune their development skills * Covers C# programming basics, Web and Windows programming, data access, graphics programming with GDI+, and basic networking * Explains how to put together basic Web and Windows applications and highlights the differences between Web and Windows programming

Professional C# 2005 : (Book is in CHM format ) Free (UPDATED) Professional C# 2005 prepares you to program in C#, and it provides the necessary background information on how the. NET architecture works. It provides examples of applications that use a variety of related technologies, including database access, dynamic web pages, advanced graphics, and directory access. The only requirement is that you are familiar with at least one other high-level language used on Windows – either C++, VB, or J++.(

Microsoft Visual C# 2005 Unleashed MAY 2006: (Book is in RAR format ) Free (UPDATED) Setting the standard for a premium C# reference, Microsoft Visual C# 2005 Unleashed provides practical examples for virtually every aspect of the C# programming language. The book is structured for progressive learning, so it can be read cover-to-cover or used as a comprehensive reference guide. (Link taken From

Morgan Kaufmann C Sharp 2 0 Practical Guide for Programmers: (Book is in PDF format ) Free (UPDATED) You dont need coddling; you dont need to be told what you already know. What you need is a book that uses your experience as a Java or C++ programmer to give you a leg up into the challenges and rewards of C#. And this Practical Guide is precisely what youre after. Written by a team that boasts extensive experience teaching C# to professionals, this book provides a practical, efficient explanation of the language itself, covering basic to advanced features and calling out all thats new in 2.0. Its instruction is always firmly situated within the context of the .NET framework and bolstered by code examples, key lessons in object-oriented programming, and installments of a realistic application programming tutorial. Concise and incisive, this is the best way to master the worlds fastest-growing and most marketable programming language.

Microsoft Visual C# 2005 Step by Step : (Book is in CHM format ) Free (UPDATED) Microsoft Visual C# is a powerful but simple language aimed primarily at developers creating applications by using the Microsoft .NET Framework. It inherits many of the best features of C++ and Microsoft Visual Basic, but few of the inconsistencies and anachronisms, resulting in a cleaner and more logical language. The advent of C# 2.0 has seen several important new features added to the language, including Generics, Iterators, and anonymous methods. (

Pro .NET 2.0 Code and Design Standards in C# : (Book is in PDF format ) Free (UPDATED) This book is special, because for the first time you get an easy-to-follow set of code and design standards that addresses the basic needs of. NET developers and application architects. The material is presented in a "what, why, where, and how" format, so it's easy to understand a given topic and apply the solution. The format facilitates fast understanding and quick reference, just what you need when you're under pressure.

C# Cookbook : (Book is in CHM format ) Free (UPDATED) With C# Cookbook, 2nd Edition, you'll be able to learn and improve your mastery of both the C# language and the .NET platform. This updated bestseller has been completely revised to account for C# 2.0, the latest version of this popular object-oriented programming language. It also includes more than 100 new code solutions (over 300 overall) to common problems and tasks that you're sure to face as a C# programmer.

Essential C# 2.0 : (Book is in CHM format ) Free (UPDATED) Essential C# 2.0 is a clear, concise guide to C#—including the features new to C# 2.0. The book clearly presents material for beginners and experts and provides contrasts and comparisons between C# and other languages. The C# language is covered comprehensively and each important construct is illustrated with succinct code examples.Following the C# introduction, readers will learn about *C# primitive data types, value types, reference types, type conversions, and arrays *Operators and control flow, loops, conditional logic, and sequential programming *Methods, parameters, exception handling, and structured programming *Classes, inheritance, structures, interfaces, and object-oriented programming *Well-formed types, operator overloading, namespaces, and garbage collection *Generics, collections, and iterators *Reflection, attributes, and declarative programming *Threading, synchronization, and multi-threaded patterns *Interoperability and unsafe code *The Common Language Infrastructure that underlies C#

Visual C# 2005 A Developer's Notebook : (Book is in CHM format ) Free (UPDATED) Visual C# 2005: A Developer's Notebook is full of no-nonsense code without the usual page-filling commentary. You'll find suggestions for further experimentation, links to on-line documentation, plus practical notes and warnings. The book also tells developers how to acquire, install and configure Visual Studio .NET 2005. Are you a coder to the core? Learn what C# 2.0 can do for you now.

GDI+ Application Custom Controls with Visual C# 2005: (Book is in CHM format ) Free (UPDATED) A fast-paced example-driven tutorial to building custom controls using Visual C# 2005 Express Edition and .NET 2.0. Showing you how to use the free Visual C# 2005 Express Edition environment to develop your controls, GDI+ Custom Controls with Visual C# 2005 will teach you how to create professional, reusable custom controls for your desktop applications in no time.

C# Programmer's Handbook : (Book is in RAR format ) FreeC# Programmer’s Handbook is a complete description of the C# language as used in .NET development for both the current version of .NET (version 1.1) and the version of .NET due out in late 2004 (version 2.0). This is the only book that will include full coverage of C# 2.0 features such as generics for the foreseeable future (next 6 months). PassWord:www.ITeBookHome.com

Advanced C# Programming : (Book is in RAR format ) FreeThis advanced resource is ideal for experienced programmers seeking practical solutions to real problems. Discover valuable coding techniques and best practices while learning to master Microsoft’s newest cross-platform programming language. PassWord:www.ITeBookHome.com

C#.net Web Developer's Guide : (Book is in RAR format ) FreeThis volume teaches Web developers to build solutions for the Microsoft .NET platform. Web developers will learn to use C# components to build services and applications available across the Internet. The focus of The C#.NET Web Developer’s Guide is on providing you with code examples that will help you leverage the functionalities of the .NET Framework Class Libraries.PassWord:www.ITeBookHome.com (Link taken

Sams Teach Yourself Visual C# 2005 in 24 Hours, Complete Starter Kit : (Book is in RAR format ) FreeLooking to break into C# programming? Sams Teach Yourself Visual C# 2005 in 24 Hours, Complete Starter Kit is a valuable resource. You will start by learning the basics of the Visual C# environment and begin to build working programs very quickly.PassWord:ebooksatkoobe(Link taken

Visual C# 2005 Recipes: A Problem-Solution Approach : (Book is in RAR format ) FreeMastering .NET development is as much about understanding the functionality of the .NET Framework as it is about the syntax and grammar of your chosen language. Visual C# 2005 Recipes: A Problem-Solution Approach recognizes this fine balance. This book meets your need for fast, effective solutions to the difficulties you encounter in your coding projects.PassWord:ebooksatkoobe

Microsoft Visual C# 2005 Express Edition Programming for the Absolute Beginner : (Book is in RAR format ) FreeMicrosoft Visual C# 2005 Express Edition Programming for the Absolute Beginner provides beginner programmers with programming instruction using Visual C# 2005 Express Edition as a foundation language. Written for the entry-level, non-professional programmer, the book assumes no prior programming or scripting experience.PassWord:ebooksatkoobe

Inside C#, Second Edition : (Book is in RAR format ) FreeAimed at those with some previous programming experience, Inside C# shows developers the unique strengths, advantages, and tips for coding with C#. This fast-paced and in-depth tutorial will let you use Microsoft's newest programming language on the emerging .NET platform successfully. The outstanding strength of this text is its in-depth language tutorial on C#, with complete coverage of basic and advanced object-oriented programming techniques

C# 2.0 : The Complete Reference : (Book is in RAR format ) FreeThis comprehensive volume is fully updated for C# 2.0 -- the newest version of Microsoft's revolutionary programming language.The changes found in C# 2.0 bring Java-like power to millions of Windows programmers worldwide. With expertly crafted explanations, insider tips, and hundreds of examples, this book fully explains every aspect of C# 2.0.

Unlocking Microsoft C# V 2.0 Programming Secrets : (Book is in RAR format ) FreeThis text is a handbook of instructions written for the programmer or analyst that shows how to insert common algorithmic functions in C# into one's source code.PassWord:ebooksatkoobe

Visual C# 2005 Demystified : (Book is in RAR format ) FreeThere's no easier, faster, or more practical way to learn the really tough subjects Visual C# 2005 Demystified explains the language and its libraries and applications as well as how to use the integrated development environment. This self-teaching guide comes complete with key points, background information, quizzes at the end of each chapter, and even a final exam.

Mastering C# database programming : (Book is in RAR format ) FreeEnter a New World of Database Programming C# and ADO.NET facilitate the development of a new generation of database applications, including remote applications that run on the Web. Mastering C# Database Programming is the resource you need to thrive in this new world. Assuming no prior experience with database programming, this book teaches you every aspect of the craft, from GUI design to server development to middle-tier implementation. If you're familiar with earlier versions of ADO, you'll master the many new features of ADO.NET all the more quickly.PassWord:www.ITeBookHome.com

Microsoft(r) Visual C#(R) 2005 Express Edition: Build a Program Now! : (Book is in RAR format ) FreeIn this lively, eye-opening, and hands-on book, all you need is a computer and the desire to learn how to program with Visual C# 2005 Express Edition. Featuring a full working edition of the software, this fun and highly visual guide walks you through a complete programming project—a desktop weather-reporting application—from start to finish. You’ll get an unintimidating introduction to the Microsoft Visual Studio® development environment and learn how to put the lightweight, easy-to-use tools in Visual C# Express to work right away—creating, compiling, testing, and delivering your first, ready-to-use program

Expert C# 2005 Business Objects, Second Edition : (Book is in PDF format ) FreeI've been desperately looking for a C# book that discussed a 3-tier architecture and how it should be applied in. NET. This book (shows) you how it can be done... — Trish Middleton,. NET Programmer Thoughts If you are an architect looking to migrate to the. NET platform you should have a look at this book. — Jack Herrington, Editor, Code Generation Network This book is a ‘soup to nuts' manual (and) if you're looking to learn a solid architecture and the concepts behind it, you've found what you're looking for

Expert C# Business Objects : (Book is in RAR format ) FreeThis book is a translation of Lhotka’s industry-standard title, Visual Basic.NET Business Objects, into the language of C#. Rockford Lhotka’s ideas continue to be extremely influential in all programmer circles of any language, but most naturally it will be C# developers over the next couple of years at least who will most likely be involved in the kinds of programming projects and architectures that Lhotka discusses. This book will benefit you! Therefore, while the VB.NET book proves its punch, the new C# version will find a more natural audience than the VB version.PassWord:www.ITeBookHome.com(

Thinking in C# : (Book is in RAR format ) FreeC# is a language, and like all languages, therefore a way of thinking. Languages channel us down particular avenues of thought, make certain ideas as obvious as a grand concourse and others as confusing and mysterious as a back alley. Different computer languages facilitate different things; there are computer languages that facilitate graphics programming and others that are best for text manipulation, many that excel in data relationships, and several whose raison d’être is pure performance.

Microsoft Visual C#. NET 2003 kick start : (Book is in ZIP format ) FreeMicrosoft Visual C# .NET 2003 Kick Start is a rapid-progression tutorial that presents the C# language to working programmers who are already familiar with another programming language or tool. This book speeds through basic concepts and focuses on practical examples showing the advantages of C# .NET 2003 in ASP programming, application design and creation, and .NET Web Services development. While Microsoft Visual C# .NET 2003 Kick Start assumes no knowledge of C# or the .NET Framework.

earning C# 2005 : Get Started with C# 2.0 and .NET Programming : (Book is in CHM format ) FreeIf you're a novice programmer and you want to learn C#, there aren't many books that will guide you. Most C# books are written for experienced C++ and Java programmers. That's why Jesse Liberty, author of the best-selling books Programming C# and Programming ASP.NET, has written an entry-level guide to C#.

Sams teach yourself C# in 24 hours : (Book is in CHM format ) FreeSams Teach Yourself C# in 24 Hours provides readers with 24 structured lessons that provide a light, but thorough introduction to C#. James Foxall moves beyond the pure syntax covered in existing books, to guide readers step-by-step through a cohesive presentation of the basics of C#.

C# Class Design Handbook: Coding Effective Classes : (Book is in RAR format ) FreeI found this book to be fantastic. I would recommend this book to any intermediate programmer that's feeling a little stuck in where to go next. — Sean Mahan, Maine Bytes The mission of the C# Class Design Handbook is to provide you with a critical understanding of designing classes, making you better equipped to take full advantage of C#'s power to create robust, flexible, reusable

Advanced C# Programming : (Book is in RAR format ) FreeThis advanced resource is ideal for experienced programmers seeking practical solutions to real problems. Discover valuable coding techniques and best practices while learning to master Microsoft’s newest cross-platform programming language. This definitive guide will show you how to expertly apply and integrate C# into your business applications

Core C# and .NET : (Book is in RAR format ) Freeritten for C# 2.0 and .NET 2.0: contains coverage of generics, Master Pages, the DataGridView, and other new features Covers Web development, Windows development, data management, security, threading, remoting, and much more Presents hundreds of non-trivial code examples that help you solve real-world problems The Complete and Comprehensive Developer's Guide to C# 2.0 and .NET 2.0 Core C# and .NET is the no-nonsense, example-rich guide to achieving exceptional results with C# 2.0 and .NET 2.0.PassWord:www.AvaxHome.ru(

Windows Forms Programming with C# : (Book is in RAR format ) FreeThe new C# language and Internet software services have received much of the attention surrounding Microsoft’s new. NET environment. However, Microsoft has also redesigned the way Windows desktop applications will be created and deployed in the future. Intended as a tutorial for C++ and Java programmers at all levels, this book shows how C# and the. NET framework can be used to develop Windows

Wrox's Visual C# 2005 Express Edition Starter Kit (Programmer to Programmer) : (Book is in RAR format ) FreeVisual C# 2005 Express Edition STARTER KIT Are you ready to jump into the exciting world of programming and create your own cutting-edge applications? Microsoft MVP F. Scott Barker clearly shows you how to program using Visual C# 2005 Express, taking you from introductions and

Programming C# : (Book is in RAR format ) FreeProgramming C#, the top selling book on Microsoft's high-performance C# programming language, is now in its fourth edition. Aimed at experienced programmers and web developers, this comprehensive guide focuses on the features and programming patterns that are new to C#, and fundamental to the programming of web services and

Professional C# Third Edition : (Book is in RAR format ) FreeC# is designed to work with .NET to provide a new framework for programming on the Windows ; platform. This comprehensive reference prepares you to program in C#, while at the same time providing the necessary background in how the .NET architecture works. In this all-new third edition, you'll be introduced to the fundamentals of C# and find updated coverage of application deployment and globalization.

C# Threading Handbook : (Book is in CHM format ) FreeThis book addresses the fundamental units of Windows and. NET programming - threads. A strong understanding of the role threads play in program execution, how multiple threads can interact in order to make efficient programs, and the pitfalls to beware of when developing multithreaded applications, are all core to a developer's ability to develop effective C# programs.

Extreme Programming Adventures in C# (DV-Microsoft Professional) : (Book is in RAR format ) FreeApply what you know about extreme programming and object-oriented design to learning C# and the Microsoft® .NET Framework on the fly. Author Ron Jeffries, a leading voice and practitioner in the extreme programming movement, demonstrates how to apply its key concepts—including the use of customer stories, customer acceptance tests, and "Spikes"—and the fundamental techniques of Simple Design, Test-Driven Development, and Refactoring to create practical, .NET-ready

C# 2.0 : Practical Guide for Programmers : (Book is in RAR format ) FreeWritten by a team that boasts extensive experience teaching C# to professionals, this book provides a practical, efficient explanation of the language itself, covering basic to advanced features and calling out all thats new in 2.0

C# and VB .NET Conversion Pocket Reference : (Book is in RAR format ) FreeThe C# & VB.NET Conversion Pocket Reference helps you easily make the switch from C# to Visual Basic .NET and vice versa. Differences between the two languages occur in three main areas: syntax, object-oriented principles, and the Visual Studio .NET IDE.

C# 2005 For Dummies : (Book is in RAR format ) FreeC# is Microsoft's object-oriented programming language designed for improving productivity in the development of Web applications Fully revised for C# 2005, this book begins with creating a C# program, then moves into C# and object-oriented programming fundamentals, Windows programming with C# and Visual Studio, and debugging and error handling A friendly, conversational approach to understanding C#.(

Beginning C# Objects From Concepts to Code : (Book is in RAR format ) FreeLearning to design objects effectively with C# is the goal of Beginning C# Objects: From Concepts to Code. This comprehensive yet approachable guide to object oriented programming using UML and today's hottest programming language, which is C#.(Link taken From http://www.itebookhome.com/)

A Programmer's Introduction to C#: (Book is in RAR format ) FreeC# is the key language for Microsoft's next generation of Windows services, the .NET platform. This new programming language is fast and modern and was designed to increase programmer productivity. C# enables programmers to quickly build a wide range of applications for the new Microsoft .NET platform.

Distributed .NET Programming in C#: (Book is in RAR format ) FreeWith the release of. NET, Microsoft has once again altered the distributed programming landscape. Almost everything has changed, from data access, to remote object calls, to the deployment of software components. And of course,. NET introduces a new technology in XML Web services that may revolutionize Web development. Distributed. NET Programming in C# describes how to use these new. NET technologies to build fast, scalable,

C# COM+ Programming: (Book is in RAR format ) FreeC# COM+ Programming is a must-have for developers already working with COM+ who are ready to transition to the .NET Platform. You will be able to take your existing skills as a COM+ component programmer into the .NET Framework quickly

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What is Tornado?

tornado is a violently rotating column of air which is in contact with both a cumulonimbus (or, in rare cases, a cumulus) cloud base and the surface of the earth. Tornadoes come in many sizes, but are typically in the form of a visible condensation funnel, with the narrow end touching the earth. Often, a cloud of debris encircles the lower portion of the funnel.

Most tornadoes have wind speeds of 110 mph (175 km/h) or less, are approximately 250 feet (75 m) across, and travel a few miles (several kilometers) before dissipating. However, some tornadoes attain wind speeds of more than 300 mph (480 km/h), stretch more than a mile (1.6 km) across, and stay on the ground for dozens of miles (more than 100 km).[1][2][3]

Although tornadoes have been observed on every continent except Antarctica, most occur in the United States.[4] Other areas where they commonly occur include south-central Canada, south-central and eastern Asia, east-central South America, Southern Africa, northwestern and central Europe, Italy, western and southeastern Australia, and New Zealand.[5]

Types of tornadoes
True tornadoes
Multiple vortex tornado

A multiple vortex tornado is a type of tornado in which two or more columns of spinning air rotate around a common center. Multivortex structure can occur in almost any circulation, however it is very often observed in intense tornadoes.
Satellite tornado
A satellite tornado is a term for a weaker tornado which forms very near a large, strong tornado contained within the same mesocyclone. The satellite tornado may appear to "orbit" the larger tornado (hence the name), giving the appearance of one, large multi-vortex tornado. However, a satellite tornado is a distinct funnel, and is much smaller than the main funnel.[3]

A waterspout near the Florida Keys.Waterspout
A waterspout is officially defined by the U.S. National Weather Service simply as a tornado over water. Amongst researchers, however, they are typically divided into two categories: "fair weather" waterspouts, and tornadic waterspouts.
"Fair weather" waterspouts are the less-severe (but far more common) variety, and are similar in dynamics to dust devils and landspouts.[13] They form from the bases of cumulus congestus (also called "convective cumulus") cloud towers in tropical and semitropical waters.[13] They have relatively weak winds (F0 on the Fujita scale), smooth laminar walls, and typically travel very slowly, if at all (since the cloud they are attached to is being formed by convective action instead of the interaction between colliding fronts).[13] They occur more commonly in the Florida Keys than anywhere on Earth.[14]
Tornadic waterspouts are more literally "tornadoes over water", and form the same way as tornadoes. A tornado which spawns in the traditional manner on land and later crosses into a body of water would also be considered a tornadic waterspout. Since they form from severe thunderstorms and have the capacity to be far more intense, faster, and longer-lived than their fair weather cousins, they are considered to be far more dangerous.

A landspout near North Platte, Nebraska on May 22, 2004.Landspout

A landspout is an unofficial term for a tornado not associated with a mesocyclone. The name stems from their characterization as essentially a "fair weather waterspout on land". They share most of the characteristics with their water-based brethren, including relative weakness, short lifespan, and a small, smooth condensation funnel which often does not reach the ground. Landspouts also create a distinctively laminar cloud of dust when they make contact with the ground, owing to their differing mechanics from true mesoform tornadoes. Though usually weaker than classic tornadoes, they still possess strong winds and can cause serious damage.[3][15]

Tornado-like circulations
Gustnado
A gustnado (gust front tornado) is a small, vertical swirl associated with a gust front or downburst. Because they are technically not associated with the cloud base, there is some debate as to whether or not gustnadoes are actually tornadoes. They are formed when fast moving cold, dry outflow air from a thunderstorm is blown through a mass of stationary, warm, moist air near the outflow boundary, resulting in a "rolling" effect (often exemplified through a roll cloud). If low level wind shear is strong enough, the rotation can be turned horizontally (or diagonally) and make contact with the ground. The result is a gustnado.[3][16] They usually cause small areas of heavier rotational wind damage among areas of straight-line wind damage. It is also worth noting that since they are absent of any Coriolis influence from a mesocyclone, they seem to be alternately cyclonic and anticyclonic without preference.

Dust devil in Johnsonville, South Carolina.Dust devil
A dust devil resembles a tornado in that it is a vertical swirling column of air. However, they form under clear skies and are rarely as strong as even the weakest tornadoes. They form when a strong convective updraft is formed near the ground on a hot day. If there is enough low level wind shear, the column of hot, rising air can develop a small cyclonic motion that can be seen near the ground. They are not considered tornadoes because they form during fair weather and are not associated with any actual cloud. However, they can, on occasion, result in major damage and fatalities, especially in arid areas.[17][18]
Fire whirl
Tornado-like circulations occasionally occur near large, intense wildfires and are called fire whirls. They are not considered tornadoes except in the rare case where they connect to a pyrocumulus or other cumuliform cloud above. Fire whirls usually are not as strong as tornadoes associated with thunderstorms. However, they can produce significant damage.[8]
Cold air vortex
A cold air vortex or shear funnel is a tiny, harmless funnel cloud which occasionally forms underneath or on the sides of normal cumuliform clouds, rarely causing any winds at ground-level.[19] Their genesis and mechanics are poorly understood, as they are quite rare, short lived, and hard to spot (due to their non-rotational nature and small size).

Characteristics

A wedge tornado, nearly a mile wide.
A rope tornado in its dissipating stage.
Shape
Most tornadoes take on the appearance of a narrow funnel, a few hundred yards (a few hundred meters) across, with a small cloud of debris near the ground. However, tornadoes can appear in many shapes and sizes.

Small, relatively weak landspouts may only be visible as a small swirl of dust on the ground. While the condensation funnel may not extend all the way to the ground, if associated surface winds are greater than 40 mph (64 km/h), the circulation is considered a tornado.[15] Large single-vortex tornadoes can look like large wedges stuck into the ground, and so are known as wedge tornadoes or wedges. A wedge can be so wide that it appears to be a block of dark clouds, wider than the distance from the cloud base to the ground. Even experienced storm observers may not be able to tell the difference between a low-hanging cloud and a wedge tornado from a distance.[20]


Size
In the United States, an average tornado is around 500 feet (150 m) across, and stays on the ground for 5 miles (8 km).[17] While this is the average, there is an extremely wide range of tornado sizes, even for typical tornadoes. Weak tornadoes, or strong but dissipating tornadoes, can be exceedingly narrow, sometimes only a few feet across. In fact, a tornado was once reported to have a damage path only 7 feet (2 m) long.[17] On the other end of the spectrum, wedge tornadoes can have a damage path a mile (1.6 km) wide or more. A tornado that affected Hallam, Nebraska on May 22, 2004 was at one point 2.5 miles (4 km) wide at the ground.[2]

In terms of path length, the Tri-State Tornado, which affected parts of Missouri, Illinois, and Indiana on March 18, 1925, was officially on the ground continuously for 219 miles (352 km). Many tornadoes which appear to have path lengths of 100 miles or longer are actually a family of tornadoes which have formed in quick succession; however, there is no substantial evidence that this occurred in the case of the Tri-State Tornado.[8] In fact, modern reanalysis of the path suggests that the tornado began 15 miles (24 km) further west than previously thought.[22]


Appearance

Tornadoes, depending on the environment in which they form, can have a wide range of colors. Tornadoes which form in a dry environment can be nearly invisible, marked only by swirling debris at the base of the funnel. Condensation funnels which pick up little or no debris can be gray to white. While travelling over a body of water as a waterspout, they can turn very white or even blue. Funnels which move slowly, ingesting a lot of debris and dirt, are usually darker, taking on the color of debris. Tornadoes in the Great Plains can turn red because of the reddish tint of the soil, and tornadoes in mountainous areas can travel over snow-covered ground, turning brilliantly white in the process.[17]
These are two photographs of the Waurika, Oklahoma tornado of May 30, 1976, taken at nearly the same time by two different photographers. In the top picture, the tornado is front-lit, with the sun behind the east-facing camera, so the funnel appears nearly white. In the lower image, where the camera is facing the opposite direction, the tornado is back-lit, with the sun behind the clouds.[23]Lighting conditions are also a major factor in the appearance of a tornado. A tornado which is "back-lit", or viewed with the sun behind it, will appear to be very dark. The same tornado, viewed with the sun at the observer's back, may appear gray or brilliant white. Tornadoes which occur near the time of sunset can be many different colors, appearing in hues of yellow, orange, and pink.[24][12]

Rotation

Tornadoes normally rotate cyclonically in direction (counterclockwise in the northern hemisphere, clockwise in the southern). While large-scale storms always rotate cyclonically due to the Coriolis effect, thunderstorms and tornadoes are so small that the direct influence of Coriolis effect is inconsequential, as demonstrated physically by the Rossby number. Supercells and tornadoes would rotate cyclonically even without the Coriolis effect, as evidenced by their doing so in numerical simulations which neglect the Coriolis component.[28][29] Low-level mesocyclones and tornadoes owe their rotation to complex processes within the supercell and ambient environment.[30]

Sound and seismology

Tornadoes emit widely on the acoustics spectrum and multiple mechanisms cause the sound of a tornado. Various sounds of tornadoes have been reported throughout time, mostly related to familiar sounds for the earwitness and generally some variation of a whooshing roar. Among the popularly reported sounds are a freight train, rushing rapids or a waterfall, and a jet engine from close proximity, or combinations thereof. Many tornadoes are not audible from much distance; the nature and propagation distance of the audible sound depends on atmospheric conditions and topography.

The winds of both the tornado vortex and constituent turbulent eddies, as well as airflow interaction with the surface and debris, contribute to the sound of a tornado; this is evidenced by both funnel clouds and tornadoes having sounds, and the associated sounds differing. Funnel clouds and small tornadoes are reported as a whistling, whining, humming, or the buzzing of innumerable bees or electricity, or more or less harmonic, whereas many tornadoes are reported as a continuous, deep rumbling, or an irregular sound of “noise”.[33] It is important to note that many tornadoes do not produce any sound unless one is within very close proximity, so sound is not reliable forewarning of a tornado; and that not only tornadoes but also any strong, damaging wind, even a severe hail volley or continuous thunder within a thunderstorm may produce a roaring sound.[34]

Electromagnetic, lightning, and other effects

Tornadoes emit on the electromagnetic spectrum, for example, with sferics and E-field effects detected.[citation needed] The effects vary, mostly with little observed consistency. Luminosity has been reported in the past, and is probably due to misidentification of external light sources such as lightning, city lights, and power flashes from broken lines, as internal sources are now uncommonly reported and are not known to ever been recorded. Correlations with patterns of lightning activity have also been observed, however, no consistent correlations have been advanced. Electromagnetics and lightning have little to nothing to do directly with what drives tornadoes (tornadoes are basically a thermodynamic phenomenon), though there are likely connections with the storm and environment affecting both phenomena.

In addition to winds, tornadoes also exhibit changes in atmospheric variables such as temperature, moisture, and pressure; for example, in June 2003, a probe measured a 100 mb (hPa) (2.95 inHg) pressure