1、Map Projections and TypesCartographyThe art and science of making maps,including data compilation,layout,and design.Also concerned with the interpretation of mapped patterns.A stone tablet found in a cave in Abauntz in the Navarra region of northern Spain is believed to contain the earliest known re
2、presentation of a landscape.MapsVisual representation of the earths surface or the phenomenon(any observable occurrence)that occur on the earths surface.Map ScaleThe degree to which a map“zooms in”on the area it is representing.Scale tells you what extent the portion of the earth represented on the
3、map has been reduced from its original size to fit on the map.For example,1 inch on a map may equal 10 miles in the real world.That scale might be written as 1 inch=10 miles.Sometimes,scale is indicated as a fraction.“1/10 miles”or“1:10 miles”means 1 inch on the map equals 10 miles in the real world
4、.THIS IS THE TRICKY PARTCounterintuitive part of mapping:“LARGE”OR“SMALL”scale.“LARGE”OR“SMALL”scale.The more“zoomed in”the map is on an area,the larger is its map scale.large-scale map depicts a smaller areaThe less“zoomed in”the map is on an area,the smaller is its scale.Small-scale map depicts a
5、larger areaMap ProjectionsEarth is ROUND!ROUND!So?Transforming something spherical into something flat means that the 2-D image will never exactly represent what is visible in three-dimensions.Geographers use numerous mathematical equations to produce map projections.All flat maps have some distorti
6、on in their representation of:DistanceShapeAreaOr direction.Types of ProjectionsEqual-area(or equivalent)projections:maps that maintain area but distort other properties.Conformal(or orthomorphic)projections:maps that maintain shape but distort other properties(it is impossible to have a projection
7、that is both conformal and equal area).Azimuthal projections:maps that maintain direction but distort other properties.Equidistant projections:maps that maintain distance but distort other properties.Mercator ProjectionCylindrical map projectionUseful for navigation because it maintains accurate dir
8、ectionFamous for their distortion in area that makes landmasses at the poles appear oversizedMercator ProjectionPeters ProjectionCylindrical map projection Attempts to retain all the accurate sizes of all the worlds landmassesSometimes used as a political statement-that we should refocus our attenti
9、on to the tropics,home to large landmasses and many of the worlds poorest countries.Peters ProjectionFuller ProjectionMaintains the accurate size and shape of landmasses Completely rearranges direction such that the four cardinal directions(north,south,east,and west)no longer have any meaning.Fuller
10、 ProjectionRobinson ProjectionAttempts to balance several possible projection errors.Does not maintain completely accurate area,shape,distance,or direction,but it minimizes errors in each.Used by National GeographicRobinson ProjectionAzimuthal ProjectionPlanarFormed when a flat piece of paper is pla
11、ced on top of the globe and,as described earlier,a light source projects the surrounding areas onto the map.Either the North Pole or South Pole is oriented at the center of the map which gives the viewer the impression of looking up or down at the earth.Azimuthal ProjectionMap TypesReference MapShow
12、 locations of places and geographic features.Thematic MapTell a story about the degree of an attribute,the pattern of its distribution,or its movement.Thematic MapContour Maps(Isopleths)Isolines-Isolines-Lines on a map depicting areas of same or like values.Contour maps use isolinesisolines,or conto
13、ur lines,to depict where the same elevation exists.The contour intervalcontour interval of a contour map is the difference in elevation between successive contour lines.Contour MapsProportional Symbols MapThe proportional symbol technique uses symbols of different sizes to represent data associated
14、with different areas or locations within the map.Proportional Symbols MapProportional Symbols MapA dot may be used to locate each occurrence of a phenomenon.Where appropriate,a dot may indicate any number of entities,for example,one dot for every 100 voters.Dot MapMilitary families in OhioChoropleth
15、 MapShows statistical data aggregated over predefined regions,such as counties or states,by coloringcoloring or shading these regions.For example,countries with higher rates of infant mortality might appear darker on a choropleth map.Choropleth MapCartogramA cartogramcartogram is a map in which some
16、 thematic mapping variable is substituted for land area or distance.The geometry or space of the map is distorted in order to convey the information of this alternate variable.CartogramCartogramCartogramGIS mapA geographic information system(GIS)integrates hardware,software,and data for capturing,ma
17、naging,analyzing,and displaying all forms of geographically referenced information.GIS allows us to view,understand,question,interpret,and visualize data in many ways that reveal relationships,patterns,and trends in the form of maps,globes,reports,and charts.GIS mapLocation ChartVisualizationsVisualizationsp 经常不断地学习,你就什么都知道。你知道得越多,你就越有力量p Study Constantly,And You Will Know Everything.The More You Know,The More Powerful You Will Be写在最后谢谢大家荣幸这一路，与你同行ItS An Honor To Walk With You All The Way演讲人：XXXXXX 时 间：XX年XX月XX日
