Physical Geography - Version 1 Unit 1 Introduction to Geography as a Discipline

Figure Lake Sabrina , a feature ner Bishop , California . Image by Jeremy is under a license . UNIT INTRODUCTION TO GEOGRAPHY AS A DISCIPLINE Goals Objectives of this unit Develop an understanding of geographic and scientific knowledge and inquiry . Describe the basic model of the scientific method and how scientists use it to understand the natural world . Explain the importance of understanding location , including the latitude longitude . Compare and contrast the various types of technologies used today . GEOGRAPHY

SCIENTIFIC GEOGRAPHIC INQUIRY Physical Geography is the study of our home planet and all of its components its lands ( lithosphere ) waters ( hydrosphere ) living organisms ( biosphere ) atmosphere , and interior . In this book , some chapters are devoted to the processes that shape the lands and impact people . Other chapters depict the processes ofthe atmosphere and its relationship to the surface and all our living creatures . For as long as people have been on the planet , humans have had to live within Earth boundaries . Now human life is having a profound effect on the planet , with both a positive and negative result . Thejourney to better understanding Earth begins here with an exploration of how scientists learn about the natural world and introduce you to the study of physical geography . Scientific Inquiry Science is a path to gaining knowledge about the natural world . The study of science also includes the body of knowledge that has been collected through scientific inquiry . To conduct a scientific investigation , scientists ask testable questions that can be systematically observed and carefully evidenced collected . Then they use logical reasoning and some imagination to develop a testable idea , called a hypothesis , along with explanations to explain the idea . Finally , scientists design and conduct experiments based on their hypotheses . Scientists seek to understand the natural world by asking questions and then trying to answer the questions with evidence and logic . A scientific question must be testable and supported by empirical data , it does not rely on faith or opinion . Our understanding of Earth natural processes helps us to answer questions such as , why earthquakes occur where they do and what are the consequences of adding excess greenhouse gases into the atmosphere . Scientific research may be done to build knowledge or to solve problems , and lead to scientific discoveries and technological advances . Research often aids in the development of applied research . Sometimes the results of the research may be applied long after the research was completed . Sometimes the results are discovered while scientists are conducting their research . Some ideas are not testable . For example , supernatural phenomena , such as stories of ghosts , vampires , or The Yeti , can not be tested . Scientists describe what they see , whether in nature or a laboratory . Science is the realm of facts and observations , not moral judgments . Scientists increase our technological knowledge , but science does not determine how or if we use that knowledge . Scientists learned to build an atomic bomb , but scientists did decide whether or when to use it . Scientists have accumulated data on warming temperatures their models have shown the likely causes of this warming . But although scientists are largely in agreement on the causes of global warming , they ca force politicians or individuals to pass laws , or change behaviors . For science to work , scientists must make some assumptions . The rules of nature , whether GEOGRAPHY

simple or complex , are the same everywhere in the universe . Natural events , structures , and have causes and evidence from the world can be used to learn about those causes . The objects and events in nature can be understood through careful , systematic study . Scientific ideas can change if we gather new data or learn more . An idea , even one that is accepted today , may need to be changed slightly or be entirely replaced if new evidence is found that contradicts it . Scientific knowledge can withstand the test of time because accepted ideas in science become more reliable as they survive more tests . Geographic Inquiry Geography is the study of the physical and cultural environments ofthe earth . What makes geography different from other disciplines is its focus on spatial inquiry and analysis . also try to look for connections between things such as patterns , movement and migration , trends , and so forth . This process is called either geographic or spatial inquiry . To do this , go through a geographic methodology that is quite similar to the scientific method , but again with a geographic or spatial emphasis . Ask a geographic question . Ask questions about spatial relationships in the world around you , such as the location of your college as it pertains to your home , high school , or work . Acquire geographic resources . Identify data and information that you need to answer your question . Explore geographic data . Turn the data into maps , tables , and graphs , and look for patterns and relationships by utilizing computer programs and statistics . Analyze geographic information . Determine what the patterns and relationships mean concerning your question . This is where critical thinking comes to play once observing the results you then begin to develop future work or perhaps ask even more questions . Knowing where something is , how its location influences its characteristics , and how its location influences relationships with other phenomena are the foundation of geographic thinking . Like other research methods , it also asks you to explore , analyze , and act upon the things you find . It also is important to recognize that this is the same method used by professionals around the world working to address social , economic , political , environmental and a range of scientific issues . GEOGRAPHY

THE SCIENTIFIC METHOD You have probably learned that the scientific method is a series of steps that help answer research questions . Scientists use data and evidence gathered from observations , experience , or experiments to answer their questions and to essentially create even more hypotheses . But scientific inquiry rarely proceeds in the same sequence of steps outlined by the scientific method . For example , the order of the steps might change because more questions arise from the data that is collected . Still , to come to verifiable conclusions , logical , repeatable steps of the scientific method must be followed . An example flow chart has been provided below to show the steps of the scientific method . As an example , what if your question was , do taller people wear bigger shoes ?

What data would you need ?

How would you collect that data , and how would you test your hypothesis ?

Figure Flow chart of the Scientific Method . Image is in the public domain . GEOGRAPHY Scientific Questioning The most important thing a scientist can do is to ask critical thinking questions . What makes the San Andreas Fault different from the Hollywood Fault ?

Why does Earth have so many varied life forms but other local planets in the solar system do not ?

What impacts could a warmer planet have on weather and climate systems ?

can answer testable questions about the natural world , but what makes a question impossible to test ?

Some untestable questions are whether ghosts exist or whether there is life after death . A testable question might be about how to reduce soil erosion on a farm . A farmer has heard of a planting method called farming . Using this process eliminates the need for plowing the land . The farmer question is Will farming reduce the erosion ofthe farmland ?

Scientific research To answer a question , a scientist first finds out what is already known about the topic by reading books and magazines , searching the Internet , and talking to experts . This information will allow the scientist to create a good experimental design . Ifthis question has already been answered , the research may be enough , or it may lead to new questions . Example The farmer researches farming on the Internet , at the library , at the local farming supply store , and a few local farmers in his area . He learns about various farming methods . He learns what type of fertilizer is best to use and what the best crop spacing would be . From his research , he learns that farming can be a way to reduce carbon dioxide emissions into the atmosphere , which helps in the fight against global warming . Figure Farmers working in a greenhouse . Image by in the public domain . GEOGRAPHY

Hypothesis With the information collected from background research , the scientist creates a plausible explanation for the question . This is a hypothesis . The hypothesis must directly relate to the question and must be testable . Having a hypothesis guides a scientist in designing experiments and interpreting data . Example The farmer hypothesis is this farming will decrease soil erosion on hills of similar steepness as compared to the traditional farming technique because there will be fewer disturbances to the soil . Data Collection Observation Experimentation To support or refute a hypothesis , the scientist must collect data . A great deal of logic and effort goes into designing tests to collect data so the data can answer scientific questions . Data is usually collected by experiment or observation . Observation is used to collect data when it is not possible , for practical or ethical reasons , to perform experiments . Written descriptions are examples of qualitative data based on observations . Scientists use many different types of instruments to make quantitative measurements , such as an electron microscope can be used to explore tiny objects or telescopes to learn about the universe . Experiments may involve chemicals and test tubes , or they may require advanced technologies like a electron microscope or radio telescope . Atmospheric scientists may collect data by analyzing the gases present in gas samples , and may perform chemical analyses on rock samples . A good experiment must have one factor that can be manipulated or changed . This is the independent variable . The rest of the factors must remain the same . They are the experimental controls . The outcome of the experiment , or what changes as a result of the experiment , is the dependent variable . The dependent variable depends on the independent variable . Figure Example of farming in a soybean . Image by Tim , Natural Resources Conservation Service is in the public domain . GEOGRAPHY

As an example The farmer experiments on two separate hills . The hills have similar steepness and receive similar amounts of sunshine . On one , the farmer uses a traditional farming technique that includes plowing . On the other , he uses a technique , spacing plants farther apart and using specialized equipment for planting . The plants on both hillsides receive identical amounts of water and fertilizer . The farmer measures plant growth on both hillsides . In this experiment what are the independent , experimental and dependent variables ?

The independent variable is the farming traditional or that is what is being manipulated . For a fair comparison of the two farming techniques , the two hills must have the same slope and the same amount of fertilizer and water . These are the experimental controls . The amount of erosion is the dependent variable . It is what the farmer is measuring . During an experiment , scientists make many measurements . Data in the form of numbers is quantitative . Data gathered from advanced equipment usually goes directly into a computer , or the scientist may put the data into a spreadsheet . Charts and tables display data and should be clearly labeled . Statistical analysis makes more effective use of data by allowing scientists to show relationships between different categories of data . Statistics can make sense of the variability in a data set . Graphs help scientists to visually understand the relationships between data . Pictures are created so that other interested people can see the relationships easily . Conclusions Scientists study graphs , tables , diagrams , images , descriptions , and all other available data to conclude from their experiments . Is there an answer to the question based on the results of the experiment ?

Was the hypothesis supported ?

Some experiments completely support a hypothesis , and some do not . If a hypothesis is shown to be wrong , the experiment was not a failure . All experimental results contribute to knowledge . Experiments that do or do not support a hypothesis may lead to even more questions and more experiments . Example After a year , the farmer finds that erosion on the traditionally farmed hill is times greater than erosion on the hill . The plants on the plots are taller and the soil moisture is higher . The farmer decides to convert to farming for future crops . The farmer continues researching to see what other factors may help reduce erosion . Theory As scientists conduct experiments and make observations to test a hypothesis , over time they collect a lot of data . If a hypothesis explains all the data and none ofthe data contradicts the hypothesis , the hypothesis becomes a theory . A scientific theory is supported by many observations and has no major inconsistencies . A theory must be constantly tested and revised . Once a theory has been developed , it can be used to predict behavior . A theory provides a GEOGRAPHY

model of reality that is simpler than the phenomenon itself . Even a theory can be overthrown if conflicting data is discovered . However , a longstanding theory that has lots of evidence to back it up is less likely to be overthrown than a newer theory . Science does not prove anything beyond a shadow of a doubt . Scientists seek evidence that supports or refutes an idea . is no significant evidence to refute an idea and a lot of evidence to support it , the idea is accepted . The more lines of evidence that support an idea , the more likely it will stand the test of time . The value of a theory is when scientists can use it to offer reliable explanations and make accurate predictions . GEOGRAPHIC GRID SYSTEM Geography is about spatial understanding , which requires an accurate grid system to determine absolute and relative location . Absolute location is the exact and coordinate on the Earth . Relative location is the location of something relative to other entities . For example , when you use Google Maps , you put in an absolute location . But as you start driving , the device tells you to turn right or left relative to objects on the ground Turn left on exit is relative to the other exit points . Or if you give directions to your house , you often use relative locations to help them understand how to get to your house . Great Small Circles Much of Earth grid system is based on the location of the North Pole , South Pole , and the Equator . The poles are considered points . The plane of the equator is an imaginary horizontal line that cuts the earth into two equal halves . This brings up the topic of great and small circles . A great circle is any circle that divides the earth into a circumference of two equal halves . also the largest circle that can be drawn on a sphere . The line connecting any points along a great circle is also the shortest distance between those two points . Examples of great circles include the Equator , all lines of longitude , the line that divides the earth into day and night called the circle of illumination , and the plane ofthe ecliptic , which divides the earth into equal halves along the equator . Small circles are circles that cut the earth , but not into equal halves . GEOGRAPHY

great circle Figure Great small circles . Image by Brian is under a license . Latitude Longitude Many assume that latitude is a line connecting points on the earth and it not . Latitude is an angular measurement north or south of the equator . So , 30 degrees north means a point that is 30 degrees north of the equator . Latitude is also expressed in degrees , minutes , and seconds 360 degrees in a circle , 60 minutes ( in a degree , and 60 seconds ( in a minute . When you use Google Earth , the coordinate locations are in this format . Latitude varies from degrees ( equator ) to 90 degrees north and south ( the poles ) North Pole South Pole Prime Meridian Figure Latitude Longitude . Image by has been designated to the public domain under a Universal Public Domain Dedication connecting all points of the same latitude is called a parallel , because the lines run parallel to each other . The only parallel that is also a great circle is the equator . All other parallels are small circles . The following are the most important parallel lines GEOGRAPHY

Equator , degrees Tropic of Cancer , degrees Tropic of Capricorn , degrees Arctic Circle , degrees Antarctic Circle , degrees North Pole , 90 degrees ( infinitely small circle ) South Pole , 90 degrees ( infinitely small circle ) Latitude is also sometimes described as zones of latitude . Some of these zones of latitude include Low latitude generally between the equator and 30 degrees Midlatitude between 30 degrees and 60 degrees and High latitude latitudes greater than about 60 degrees and Equatorial within a few degrees of the equator Tropical within the tropics ( between degrees and degrees Subtropical slightly of the tropics , generally around degrees and Polar within a few degrees of the North or South Pole Longitude is the angular measurement east and west of the Prime Meridian . Like latitude , longitude is measured in degrees , minutes , and seconds . Lines connecting equal points of longitude are called meridians . But unlike parallels , meridians do not run parallel to each other . Rather they are farthest apart from each other at the equator and merge toward each other toward the poles . The problem with longitude is that there is a natural baseline like the equator is for latitude . For over a hundred years , nations used their own prime meridian which proved problematic for trade . But in 1883 an international conference in Washington was held to determine a global prime meridian . After weeks of debate , the Royal Observatory at Greenwich , England was determined as the Greenwich Meridian or also called the prime meridian for the world . So today , longitude starts at the Prime Meridian and measures east and west of that line . At 180 degrees of the Prime Meridian in the Pacific Ocean is the International Date Line . The line determines where the new day begins in the world . Now because of this , the International Date Line is not straight , rather it follows national borders so that a country is divided into two separate days ( and we think our time zones are a pain ) If you look at the map on the next page , the International Date Line is to the right in a dark , black line . Note how it is drawn to make sure nations are not divided by the International Date Line . GEOGRAPHY

Time Zones This is also a good time to take a look at time zones around the world . Ifyou refer to the map on the next page , you can see the different time zones in the various colors . Since the earth rotates 360 degrees in a period , the earth rotates 15 degrees every hour creating 24 time zones . In an ideal world , each time zone would follow lines of longitude every 15 degrees ( in each direction from the center of the time zone ) But because of political boundaries , time zones are not divided up so perfectly and vary greatly in shape and width . Greenwich , England was chosen in the century as the starting point of time worldwide . The reason was that at the time , England was the superpower of the time both militarily and economically . So , the meridian that ran through Greenwich became zero degrees or the prime meridian . Because of the earth rotation in reference to the prime meridian , locations east of the new meridian meant time was ahead while locations west of the meridian were behind in time in reference to Greenwich , England . Ultimately , when you combine parallel and meridian lines , you end up with a geographic grid system that allows you to determine your exact location on the planet . Pin It ! Time Zones Visit this interactive Time Zone Ma for more information on time zones . or Figure Global map showing time zone distribution . Image by is in the public domain . GEOGRAPHY

TECHNOLOGY Data , data , data data is everywhere . It collected every time you go to the grocery store and use their card to reduce the costs when you click on a link on Facebook , or when you do any kind of search on a search engine like Google , Bing , or Yahoo ! It is used by the state department when you are driving on a freeway , or when you use an app on a smartphone . believe that in the near future , face recognition technology will allow a sales representative to know what types of clothes you like to buy based on a database of your recent purchases at their store and others . Now there are two basic types of data you need to know spatial and data . Spatial data , also called data , is data that can be linked to a specific location on Earth . data is becoming big business because it is just data , but data that can be located , tracked , patterned , and modeled based on other data . Census information that is collected every 10 years is an example of spatial data . data is data that can not be specifically traced to a specific location . This might include the number of people living in a household , enrollment within a specific course , or gender information . But data can easily become spatial data if it can be linked in some way to a location . technology specialists have a method called that can be used to give spatial data a geographic location . Once data has a spatial component associated with it , the type of questions that can be asked dramatically changes . Remote Sensing Remote sensing can be defined as the ability to study objects without being in direct physical contact with them . For example , your eyes are a form of passive remote sensing because they are absorbing electromagnetic energy within the visible spectrum from distant objects and your brain is processing that energy into information . There are a variety of remote sensing platforms or devices , but they can be categorized into the following that we will look at throughout the course . Satellite imagery is a type of remotely sensed imagery taken of the Earth surface , which is produced from orbiting satellites that gather data via electromagnetic energy . Next is aerial photography , which is or digital photographs of the Earth , usually from an airplane or drone . Images are either taken from a vertical or oblique position . The third is radar , which is an interesting form of remote sensing technology that uses microwave pulses to create imagery of features on Earth . This can be from a satellite image or Doppler radar for weather forecasting . Finally , a realm of remote sensing is called Light Detection and Ranging or , which is a form of remote sensing that measures the distance of objects using laser pulses of light . GEOGRAPHY

Figure Remote sensing of the environment . Used with permission from Global Positioning Systems Another type of technology , and a key technology for acquiring accurate control points on Earth surface , is global positioning systems ( In order to determine the location of a receiver on Earth surface , a minimum of four satellites are required using a mathematical process called triangulation . Normally the process of triangulation requires a minimum of three transmitters , but because the energy sent from the satellite is traveling at the speed of light , minor errors in calculation could result in large location errors on the ground . Thus , a minimum of four satellites is often used to reduce this error . This process using the geometry to determine location is used not only in but a variety of other location needs , like finding the epicenter of earthquakes . A user can use a receiver to determine their location on Earth through a dynamic conversation with satellites in space . Each satellite transmits orbital information called the ephemeris using a highly accurate atomic clock along with its orbital position called the almanac . The receiver will use this information to determine its distance from a single satellite using the equation , where distance , rate or the speed of light ( meters per second ) and time using the atomic clock . GEOGRAPHY

Data source Data layers Street data . is A . Vegetation data , Source GAO . Figure Visual Representation of Themes in a GIS . Image is in the public domain . There is a technology that is capable of bringing together remote sensing data , data points , spatial and data , and spatial statistics into a single , dynamic system for analysis , and that is a geographic information system ( GIS ) A GIS is a powerful database system that allows users to acquire , organize , store , and most importantly analyze information about the physical and cultural environments . A GIS views the world as overlaying physical or cultural layers , each with quantifiable data that can be analyzed . A single GIS map of a national forest could have layers such as elevation , deciduous trees , evergreens , soil type , soil erosion rates , rivers and tributaries , major and minor roads , forest health , burn areas , regrowth , restoration , animal species type , trails , and more . Each of these layers would contain a database of information specific to that layer . Nearly every discipline , career path , or academic pursuit uses geographic information systems because of the vast amount of data and information about the physical and cultural world . Disciplines and career paths that use GIS include conservation , ecology , disaster response and mitigation , business , marketing , engineering , sociology , demography , astronomy , transportation , health , criminal justice and law enforcement , travel and tourism , news media , and the list could endlessly go on . GEOGRAPHY

Now , GIS primarily works from two different spatial models raster and vector . Raster based GIS models are images much like a digital picture . Each image is broken down into a series of columns and rows of pixels and each pixel is to somewhere on Earth surface is represents a specific numeric value usually a specific color or wavelength within the electromagnetic spectrum . Most remote sensing images come into a GIS as a raster layer . The other type of GIS model is called a vector model . GIS models are based on the concept of points that are again ( given an , and possibly location ) to somewhere specific on the ground . From points , lines can be created by connecting a series of points and areas can be created by closing loops of vector lines . For each of these vector layers , a database of information can be attributed to it . As an example , a vector line of rivers could have a database associated with it such as length , width , government agencies responsible for it , and anything else the GIS user wants to tie to it . What these vector models represent is also a matter of scale . For example , a city can be represented as a point or a polygon depending on how zoomed in you are to the location . A map of the world would show cities as points , whereas a map of a single county may show the city as a polygon with roads , populations , pipes , or grid systems within it . UNIT SUMMARY Physical geography is the spatial study of our home planet and all of its components its lands , waters , atmosphere , and interior . Like other sciences , physical geography is a science that is grounded in scientific knowledge using the scientific method as the fundamental way to understand the environment . and all spatial scientists require a strong background in understanding the way humans have partitioned the Earth to determine location . In order to do that , a series of lines representing angular measurements on the earth was established , known as the geographic grid system . Once that has been done , spatial knowledge can be collected and analyzed based on geographic or spatial data . This allows us to understand spatial concepts of patterns , and flows based on location and spatial boundaries . Oftentimes this geographic data must be collected and analyzed using a and dynamic technology called technology . This technology encompasses powerful remote sensing technology , global positioning systems , and geographic information systems . GEOGRAPHY