Atmospheric Sciences 101

Weather

Course Introduction

Welcome to Atmospheric Sciences 101. This course is open to all students, although it has been particularly designed to make an understanding of weather accessible for non-science majors. High school-level algebra is the only prerequisite.

In this course, you will learn fundamental concepts related to weather patterns and events, atmospheric composition and circulation, air pollution, and climate. In our study of the atmosphere, we will discover how basic principles of physics and chemistry govern familiar weather events. We will also apply these principles to develop an understanding of larger-scale phenomena, such as global wind patterns and climate. Wherever possible, I have attempted to include direct experience through experiments with household materials, personal weather observations, and retrieval of current weather maps and reports from the World Wide Web (WWW).

Weather is a subject of active interest to most people. We enjoy talking (and complaining) about it. In this course, you will learn methods of weather forecasting and try your hand at it. You will begin to see that atmospheric events are the result of many physical processes acting simultaneously and in an interdependent fashion. Within the natural system of the atmosphere, the Earth's and the oceans' many large- and small-scale interactions affect weather and climate in complex and sometimes counter-intuitive ways. For scientists, this complexity presents an irresistible intellectual challenge. For many non-scientists, it may lead to frustration with the lack of reliable forecasts and certain outcomes for long-range processes such as climate change. Your work in this course may not eliminate that frustration with our current state of weather prediction, but I hope that you will develop an appreciation of the complex physical processes operating in our atmosphere that lend it its natural beauty, power, and mystery.

Course Objectives

After successfully completing this course you will be able to

• explain the difference between weather and climate;
• describe what makes up the atmosphere and its structure;
• summarize the history of the study of the atmosphere;
• explain how the basic forms of energy contribute to our daily weather;
• describe how the exchange of energy regulates the Earth's temperature (the so-called greenhouse effect) as well as the seasons;
• describe how the evaporation and condensation of water impacts the atmosphere;
• explain how the rising and sinking of air determines how and where clouds form and also whether those clouds produce rain and snow;
• describe what causes air molecules to move and explain what that has to do with global wind patterns;
• explain how El Niño can disrupt global wind patterns;
• describe how the different regions of the atmosphere form and how the regions interact to produce our weather;
• explain how patterns of differences and interactions allow us to predict the weather;
• explain how thunderstorms and tornadoes originate, mature, and then die out; and
• explain what causes the climate to vary naturally and how human activity may be changing the climate.

The Online Environment

Your online course offers several advantages over the traditional classroom, including a comprehensive Online Student Handbook, the ability to communicate electronically with students and with your instructor, and links to a rich array of online resources.

Online Student Handbook

This handbook answers questions about your online learning course, such as how to purchase your textbook, schedule an exam, obtain a transcript, and get technical help if you need it. The handbook also provides additional resources, such as how to order books or journals from the library and how to study for an online course.

Online Resources

As an online student, you have access to a wealth of Web resources compiled to provide fast, easy access to information that supports your online learning experience. Online Resources link you to sites with help for writing and research, language learning, and library reference materials. All links have been assessed for credibility and reliability, and they are regularly monitored to ensure their usability.

Taking the time to explore these links will enrich your online learning experience and increase your understanding of the course material.

Communication with Your Instructor and Student Peers

• An online discussion forum, designed by the University of Washington award winning Catalyst team, enables you to communicate with other currently enrolled students and with your instructor. The discussion forum is the place for you to ask questions and post answers to questions that other students have asked—it's where you can get to know your instructor and other students. Your instructor does not monitor this
• In addition to participating in the Message Board, your instructor will post information in the "Messages from Your Instructor" section at the top of your syllabus. Watch this place for announcements!
• E-mail is a quick and efficient way to communicate with your instructor about feedback you've received on an assignment. You may experience—as have other online students—that you get more support and individual attention about assignments in your online class than in a traditional classroom.

About the Required Textbooks

The required textbooks are Ahrens, C. Donald. 2006. Meteorology Today: An Introduction to Weather, Climate, and the Environment. 8th ed., and the accompanying Workbook/Study Guide for Ahren's Meteorology Today, 8th ed. Lessons One through Four and Six through Nine have assigned readings from Ahrens. Occasionally the reading assignment will skip sections that are not important to the understanding of the lesson. If, however, the reading assignment includes a topic not mentioned in the online lesson commentary, assume that it is required material for the exams. The "Focus on a Special Topic" sections in Ahrens are optional unless specifically assigned. If you have questions about points not discussed in the online lesson commentary or the assignments, ask your instructor.

The online course commentaries supplement the reading assignment in Ahrens, but are not meant to summarize or replace the text. Ahrens is densely packed with details, and without the online lesson commentary it is easy to miss the crucial points.

About the Course

Along with the ten lessons, eight written assignments, and two exams, ATM S 101 also includes highlighted key terms in the lesson commentary, several self-study exercises, and a general discussion forum.

Key Terms

Each lesson includes terms that are important to the concepts you will learn in the lesson and are intended to serve as guides to your study; these terms are boldfaced and italicized where they appear in the text, and are also shown in a sidebar. You will not be held responsible for key term definitions per se, but you will be expected to use the terms in your written work and presentation material whenever possible. You will find the terms defined either in the lesson commentary, the assigned readings, or both.

Self-study Exercises

At the end of Lessons One through Four and Six through Nine, you will find a set of self-study exercises and a written assignment. The self-study exercises provide an excellent opportunity for you to test your understanding of the material before tackling the graded assignments and exams.

General Discussion Forum

A General Discussion Forum for this course is linked from your Course Syllabus. This forum allows you to communicate with currently registered students. Your instructor does not monitor this forum; consequently, if you have course-related questions for which you need an immediate answer, use your instructor's email instead.

About the Lessons

This course is divided into eight written assignments and two exams. The lessons are organized according to topic and vary in length. The course contains a number of challenging concepts. The lessons generally build upon one another. I have included the topics of hurricanes, thunderstorms, and tornadoes because they deal with observable phenomena which many students are excited to understand, and they typically rank among the most enjoyable lessons in the course.

Lesson One: Introduction to Weather and Climate

The atmosphere produces both weather and climate. You will be able to explain the difference between the two. You'll learn what makes up the atmosphere and its structure. Finally we'll talk a bit about the history of the study of the atmosphere.

Lesson Two: Energy

Energy comes in a few basic forms. Energy is a key component in the making of our daily weather. It also the major mechanism regulating Earth's temperature (the so-called greenhouse effect) as well as the seasons.

Lesson Three: Humidity, Droplets, and Clouds

Water has a major impact on the atmosphere. Water is unusual in that it can exist in our atmosphere as a gas, a liquid, or a solid. You'll learn how evaporation and condensation of water impacts the atmosphere. If enough gaseous water is present in the air then liquid droplets will form. Get enough droplets together in one place and you get fog and clouds.

Lesson Four: Clouds and Precipitation

Air in the atmosphere rises and sinks. Whether it rises or sinks depends on how temperature changes with height in the atmosphere. The rising and sinking of air is key to how and where clouds form and also whether those clouds produce rain and snow.

Lesson Five: Preparing for the Midterm Examination

The content of this lesson outlines what you need to know to study for your midterm.

Lesson Six: Winds and Global Circulation

You'll learn what causes molecules in a gas to move and what that has to do with the atmosphere. Wind is produced by a few basic forces interacting. Wind can change from day to day and from one location to another but there are also global wind patterns. El Niño is a phenomenon that can disrupt these global wind patterns.

Lesson Seven: Air Masses, Fronts, and Weather Prediction

The properties of the atmosphere vary from place to place. Much of our weather is caused by the interaction of regions of the atmosphere with different properties. You will learn how these regional differences form and how regions interact to produce our weather. Finally you'll see that patterns of differences and interactions allow us to predict the weather.

Lesson Eight: Thunderstorms and Tornadoes

Violent weather systems are perfect examples of how weather develops. We'll examine how thunderstorms and tornadoes originate, mature, and then die out.

Lesson Nine: Air Pollution and Climate Change

Pollution comes in a variety of forms from smog to acid rain to urban ozone enhancement to upper atmosphere ozone depletion. The earth's climate has varied over time. It is important to understand what causes the climate to vary naturally and how human activity may be changing the climate.

Lesson Ten: Preparing for the Final Examination

The content of this lesson outlines what you need to know to study for your final.

About the Assignments and Exams

You will complete eight written assignments, one in each lesson for Lessons One through Four and Six through Nine. (Lessons Five and Ten help you prepare for the midterm and final exams.) The assignments will occasionally include a hands-on activity for you to complete and report on in the assignment. Ask your instructor any questions you have concerning these assignments. If you get stuck on a particular part of the assignment and cannot make any measurable progress for over an hour, put that problem aside, tackle the remaining parts of the assignment, and come back to the difficult part later. If you are still perplexed and Ahrens and the online lesson commentary offer no assistance, ask your instructor for help rather than building up frustration about that particular subject.

Short Research Paper

For the Lesson Eight assignment, you will submit a three or four-page paper on a topic of your choice. A list of suggested topics and a resource list appear at the end of Lesson Two. You may pursue other topics, but only with permission. You must submit the title of your paper with Assignment 6. If you are particularly interested in the issues of air pollution and climate change covered in the last lesson of the course, I encourage you to read ahead and choose a paper topic from that lesson. The purpose of the paper is to give you extra encouragement to pursue an area of particular interest to you in the field of meteorology.

Examinations

There will be two exams: a midterm and a final. The midterm will cover the material through Lesson Four. The final exam will cover material in the entire course, with emphasis on Lessons Six through Nine. Both exams will consist of short-answer questions and problems. The questions may include visual identification of atmospheric phenomena; pay close attention to the illustrations in the assigned readings in Ahrens.

Refer to the Online Student Handbook for more information on exams.

Determining Your Final Grade

Your course grade will be based on the following:

Average of Assignments 1–7	50 percent
Assignment 8 (short paper)	10 percent
Midterm Examination	15 percent
Final Examination	25 percent

Study Tips

Begin each lesson by looking over the required reading material in Ahrens to get an idea of its organization and focus, as well as the scope of the lesson. Follow this with a careful reading of Ahrens and the online lesson commentary. Pay close attention to the stated learning objectives at the beginning of each lesson and write out explanations and notes about them as you read. Ahrens is well suited to individual learning, as it provides chapter summaries, key word lists, review questions, additional references at the end of each chapter, and a glossary. The Workbook/Study Guide is a good way to test your knowledge and determine what topics you may need to study in more detail. The online lesson commentary emphasizes the main points of each lesson, enhances the material in Ahrens, and provides some hints for studying the material.

Learn the Technical Vocabulary

There will be a considerable amount of technical terminology introduced throughout this course. Make a special effort to learn these terms as they are introduced. It is particularly important that you understand the concepts behind the vocabulary. Later concepts will be developed using this terminology, so knowing the technical vocabulary will help you to develop an understanding of the more complicated ideas presented later. Take notes of key terms and ideas as you read; active reading, with pen in hand, is often more effective for retaining information than passive reading. Although a list of key terms is included at the end of each chapter in Ahrens, you will also find highlighted key terms as they arise in the online lesson commentary.

Once you are comfortable with the assigned material, complete the written assignment. Finish each assignment before continuing with the next lesson. Doing so not only provides incentive for submitting all of the assignments in the proper order, but it will also assure that you understand, as they are introduced, the terms and concepts that will be the building blocks for more complicated ideas in subsequent chapters.

Weather Information on the World Wide Web

The first assignment will get you started on checking the weather regularly and exploring the weather resources available on the Web. Consulting these resources throughout the course will greatly enhance your experience with the phenomena we study.

You will be able to find all the weather information necessary to complete your assignments for this course at the following Web sites:

• The National Weather Service (NWS). This site provides data, satellite images, and forecast maps for the United States in an easy-to-use format. When you do Assignment 1, you may begin your weather search here.
• The Illinois Weather page at the University of Illinois at Urbana-Champaign. In Lesson Two, you may explore this site. It provides great interactive map features, satellite images, a complete glossary of terms, national and international weather reports and forecasts, and a section devoted to teaching elementary school students about weather.
• WSFO Seattle. This site provides detailed forecasts for the Northwest region, as well as other weather data.
• UW Department of Atmospheric Sciences. This site has detailed weather information for the state of Washington, links to many other weather resources on the Web, and descriptions of research projects currently being carried out by UW faculty members. This is a good place to start when you are weather surfing on your own.

Completing This Course

Try to schedule your study. Plan ahead so that it is clear when you will study and when you will submit your assignments. The Assignment Due Date form on the course syllabus will help you create your plan. Stick to your plan and pace yourself. Most students who miss deadlines or never complete their courses violate this simple rule.

You should plan to complete this course three months from your date of registration. If you are a graduating senior, check with your graduation office to find out the date all grades are due and take that into consideration when setting up your plan.

Next, enter the dates on which you intend to take the midterm and final examinations. Plan to take the final exam at least two weeks before your planned date of course completion. If you are a graduating senior, plan to take the final exam at least one month before graduation.

Third, enter planned dates for submitting each assignment. The recommended timing for this course is about one lesson a week. Don't wait until the end of the course to write the short paper required in Assignment 8. This paper allows you to follow through on something that interests you; it shouldn't be a barrier to completing the course on schedule.

About the Developer

Mark Wensnahan has an undergraduate degree in physics and a Ph.D. in atmospheric sciences, both from the University of Washington. He is currently a research scientist at the Applied Physics Lab at the University of Washington. His primary field of research is the role of the Arctic in the climate system. The Arctic is an important component of the climate system. The loss of sea ice and snow is a major positive feedback enhancing the greenhouse effect. Many climate model predictions of global warming indicate that the polar regions will show some of the largest environmental changes of any place on the planet. A key to understanding the climate system is careful monitoring. Mark's work has centered on techniques of monitoring the sea ice that covers the Arctic Ocean. His early work was in the use of satellites to determine the age and thickness of the ice. His current work is in processing nearly 50 years of data on ice thickness as measured by U.S. Navy submarines. Analysis of part of this data set indicates that the ice covering the Arctic Ocean has thinned dramatically in the last 25 years.

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