Anyone can make, share, and use web maps. You can start by going through a short example. Suppose you want to make a map that allows you to explore the food, architecture, and design destinations for San Diego. Add your data layers and specify how each will be symbolized and portrayed. Create pop-ups that enable users to explore features by clicking on them. Save your map into your My Content folder with a good description and a thoughtful name. The idea of a digital map mashup—recombining various geographic layers—is one of the great force multipliers in modern cartography.
This ability to easily share and repurpose digital content has allowed individuals to create far more ambitious maps than would be possible if they had to work in isolation or start from scratch. The rise of the map mashup expanded cartography, so that anyone could build upon the work of others. Most of the thousands of maps created and shared every day within ArcGIS are created this way—maps that build upon the data, labor, and insights of the larger community. This era of collaborative GIS has empowered everyday citizens to participate in mapping as never before.
In ArcGIS, map authors can readily access beautiful sets of professionally produced basemaps that provide the digital canvas on which to tell their stories. Each of the Esri basemaps has a theme or focus.
Their range serves the need for almost any map type. Each of the ArcGIS basemaps contains highly accurate and up-to-date information, at multiple zoom levels covering geographic scales from detailed building footprints to the entire planet. Providing data at each level of detail, for all locations on the globe, takes a small army of cartographers and eats up terabytes of data. The good news is that each of us can benefit immediately from those efforts. Some of the most widely used basemaps, such as those seen here, rack up billions of views every week.
Basemaps seem simple and relatively unobtrusive—and this is precisely their purpose. Operational overlays carry the subject matter of the map and provide the purpose for making any map. Merging a great basemap with one or more operational layers forms the heart of the modern online map. Some map authors are data creators interested in mapping their own data. Many other authors, however, need help finding operational layers; they know what they want to map but need guidance in finding the data to fully tell the story.
Fortunately, ArcGIS provides access to an array of content to use in operational layers. The GIS community, including Esri, compiles and shares thousands of ready-to-use authoritative datasets in ArcGIS, covering everything from historical census data to environmental conditions derived from live sensor networks and stunning earth observations. You will learn more about it in chapter 4.
Finding mappable, interesting geographic layers has never been easier. Blending together ready-to-use basemaps, operational layers, and statistical graphs into a live, dynamic map allows you to share geographic content in a simple and concise format. Web maps work across multiple scales. Zoom in to see additional details and gain insight. Online maps provide continuous pan and zoom.
They literally have no edges—you can pan anywhere and zoom in for greater detail. Web maps are windows into a wealth of information. Pop-ups help reach into the map for more detailed information that emerges on demand. A single window into a map can become a window into a world of related information, including charts, images, multimedia files, and analytics. The ability to link such a wide variety of content to the map has transformed how we think about maps.
Your online maps are no longer static. They can be readily and immediately updated because your layers online can contain the latest, most accurate information. When your data changes, the maps that reference that layer are also updated. Your maps can combine more than your own data. You can mash up your rich GIS data with information from other users—in fact, whatever is useful and relevant to your objectives from the entire world of GIS users.
The world is full of data, and maps help you make sense of it. There is a growing need to turn geographic data into compelling maps. People just want to create beautiful, interactive maps and infographics with live data, easily and with confidence. Smart mapping is designed to give ArcGIS users the confidence and ability to quickly make maps that are visually pleasing and effective. The map results that you see in front of you are driven by the nature of the data itself, the kind of map you want to create, and the kind of story you want to tell.
By taking much of the guesswork out of all the settings and choices that you could conceivably tweak, your initial map results are cartographically appropriate and visually pleasing. Maps use symbols like lines and different colours to show features such as rivers, roads, cities or mountains. Young geographers need to be able to understand symbols.
All these symbols help us to visualise what things on the ground actually look like. Maps also help us to know distances so that we know how far away one thing is from another. We need to be able to estimate distances on maps because all maps show the earth or regions within it as a much smaller size than their real size. To do this we need to be able to read the scale on a map. Yearning to understand our massive world will inspire one to learn and explore. Finally, I want to make sure that readers understand that this is not an anti-technology argument.
We love technology and advancements in cartography and location-based data continue to deepen our understanding of where we are. This is, however, very much an argument that no matter how far technology advances, GPS will never replace maps because of the limitations we mentioned above. The robot voice may get you from A to B, but maps will get you much further. Remember me Log in. Lost your password? Posted on July 25, April 22, by Mariana Dorbecker.
Are maps even useful anymore? Nautical Charts. Wall Maps. City Prints Maps. Travel Maps. A map usually has a legend , or key, that gives the scale of the map and explains what the various symbols represent. Some maps show relief, or changes in elevation.
A common way to show relief is contour lines, also called topographic lines. These are lines that connect points that have equal elevation. If a map shows a large enough area, contour lines form circles. A group of contour line circles inside one another indicates a change in elevation.
As elevation increases, these contour line circles indicate a hill. As elevation decreases, contour line circles indicate a depression in the earth, such as a basin. Grids Many maps include a grid pattern, or a series of crossing lines that create squares or rectangles. The grid helps people locate places on the map. On small-scale maps, the grid is often made up of latitude and longitude lines. Latitude lines run east-west around the globe , parallel to the Equator , an imaginary line that circles the middle of the Earth.
Longitude lines run north-south, from pole to pole. Latitude and longitude lines are numbered. The intersection of latitude and longitude lines, called coordinates , identify the exact location of a place.
On maps showing greater detail, the grid is often given numbers and letters. The boxes made by the grid may be called A, B, C, and so on across the top of the map, and 1, 2, 3, and so on across the left side.
The user finds the park by looking in the box where column B and row 4 cross. Title, date, author, and sources usually appear on the map though not always together. A map of areas threatened by a wildfire, for instance, would have a date, and perhaps even a time, to track the progress of the wildfire.
A historical map of the ancient Sumerian Empire would have a date range of between 5, B. Assessing accuracy and objectivity also requires checking sources. A map of a school district may list the U. Orientation refers to the presence of a compass rose or simply an arrow indicating directions on the map.
If only an arrow is used, the arrow usually points north. Map Projections Transferring information from the spherical , or ball-shaped, surface of Earth onto a flat piece of paper is called projection. A globe, a spherical model of Earth, accurately represents the shapes and locations of the continents. But if a globe were cut in half and each half were flattened out into a map, the result would be wrinkled and torn. The size, shape, and relative location of land masses would change.
Projection is a major challenge for cartographers. Every map has some sort of distortion. The larger the area covered by a map, the greater the distortion. Features such as size, shape, distance, or scale can be measured accurately on Earth, but once projected on a flat surface only some, not all, of these qualities can be accurately represented.
For example, a map can retain either the correct sizes of landmasses or the correct shapes of very small areas, but not both. This determines which projection to use. For example, conformal maps show true shapes of small areas but distort size. Equal area maps distort shape and direction but show true relative sizes of all areas. There are three basic kinds of projections: planar, conical, and cylindrical. Each is useful in different situations.
Imagine touching a globe with a piece of cardboard, mapping that point of contact, then projecting the rest of map onto the cardboard around that point. They are often used for maps of one of the poles. Imagine you wrapped a cone around Earth, putting the point of the cone over one of the poles. That is a conical projection.
The cone intersects the globe along one or two lines of latitude. When the cone is unwrapped and made into a flat map, latitude lines appear curved in circles or semicircles. Lines of longitude are straight and come together at one pole. In conical projection, areas in the mid-latitudes—regions that are neither close to the Equator nor close to the poles—are represented fairly accurately. For this reason, conical projections are often used for maps of the United States, most of which lies in the mid-latitudes.
The cylinder touches Earth along one line, most often the Equator. When the cylinder is cut open and flattened into a map, the regions near the Equator are the most accurate.
Regions near the poles are the most distorted. Surveying and Remote Sensing Cartographers rely on survey data for accurate information about the planet.
Surveying is the science of determining the exact size, shape, and location of a piece of land. Surveyors gather information from regions both above sea level and beneath bodies of water. Surveying can be done on foot. Surveyors use many instruments to measure the features, or topography , of the land. A compass, measuring device, and theodolites are often used by surveyors doing field work. A theodolite is an instrument that measures angles.
A surveyor may calculate the angle of hills, valleys, and other features by using a theodolite, which is usually mounted on a tripod , or three-legged platform. Today, many surveyors use remote sensing to collect data about an area without actually physically touching it.
Sensors that detect light or radiation emitted by objects are mounted to airplanes or space satellites, collecting information about places on Earth from above. One method of remote sensing is aerial photography, taking photographs of Earth from the air. Aerial photography has eliminated much of the legwork for surveyors and has allowed precise surveying of some places that are impossible to reach on foot.
Satellites, spacecraft that orbit Earth, perform remote sensing. For example, Landsat , a satellite that circles Earth 14 times a day, transmits huge volumes of data to computers on Earth.
The data can be used to quickly make or correct maps.
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