CONTINUOUSLY VARIABLE PROPORTIONAL CIRCLE MAP

This continuously variable proportional circle map has been published by the New York Times to show human West Nile Virus cases across the United States. The varied sizes of the circles relate to the specific number of cases (measured variable) in each state. If you consider how much water and mosquitoes we have in Florida, it looks like we were pretty lucky for this particular season and Colorado got slammed. The numbers and circles really stand out at this size but I would be interested to see the original printed version and if it would be this clear.

http://mapmaker.rutgers.edu/355/links.html

DOQQ

This is an amazing Color IR Digital Orthographic Quarter-Quad (DOQQ) overlaid with a thermal mosaic. It is basically a georeferenced and orthorectified aerial photo of the Colina Fire in Riverside County, CA September 10, 2007. By looking closely you can see where four DOQQs have been pieced together to get the entire area and you can also see the outline of the separate thermal image. The USDA Forest Service has this map and many others on their website to illustrate the use of a thermal imaging radiometer. The DOQQs are great because they allow for more accurate measurement of distance, areas, angles and positions which would be critical in a fire fighting situation.

Link to website:
http://www.fireimaging.com/fires/2007/california/colina/253/index.html

DEM

This digital elevation model, or DEM, of the Dundas Valley, in Hamilton, Ontario, CA has been colorized to bring out the relief. The lower elevation values are shaded in green while the higher ones are orange. It looks like they have overlaid the DEM with a layer of street data for reference. If this map is used for public display, the street data would certainly help give people a better understanding of location. By rotating this DEM you might get a better view of the elevations and really see the differences across the subject area. This site has some fantastic images and maps.

Link to website:
http://map.hamilton.ca/maphamilton/S_Files/aboutimages.aspx

DLG

A digital line graph (DLG) contains a wide variety of information like topography, hydrography, boundaries, roads, and utility lines. The data is in vector format and the map features are stored as points, lines, and polygons. This is a map of the 28,000 acre Tosohatchee State Reserve in Orange County, Florida which includes USGS DLG data to show the streams, rivers, lakes, wetlands, roads, railroads, power lines, buildings and other geographic and man-made features. It might also be classified as a hypsometric map because a third variable is represented by the use of different colors to delineate wetlands, water and land. There are also lines that may/may not be contours showing the shape and elevation of this area. The website has some great information about this reserve and several different detailed maps for public use.

Click twice on the map to get a large, clear image.

Link to website:
http://www.outintheboonies.com/Tosohatchee/

DRG

A digital raster graphic (DRG) is a scanned and georectified image of a USGS standard series topographic map. This DRG of Wyoming is a digital map product available for free download from the website listed below. It is not a very clear picture but you can make out the topography and use it for doing work in a GIS. Because it is georectified, it contains spatial reference information that will communicate the spatial location of features on the map. The raster format records, stores and processes cartographic data in a cell or pixel. Of course, you have to be careful with the sources for DRGs and make sure you know how they are georeferenced.

If you click the map twice the image is a bit clearer.

Link to website:
http://wgiac.state.wy.us/scripts/DRGMAP/DRGmap.aspx?Area_Type=250K

ISOPLETH MAP

According to one of our reading assignments, an isopleth is a line of equal value and contouring is the process of drawing isopleths. Several of the previous maps collected for my project could fall into this category. I think isobars, isotachs, isohyets and isopachs would all be considered isopleths. These maps are commonly used for mapping surface elevations, amounts of precipitation, atmospheric pressure, and numerous other measurements that can be viewed statistically as a third dimension. The map I have chosen is a good illustration of isopleth lines showing field pH levels recorded across the United States. It is listed by the North Fork Watershed Association in Brookville, PA as an example in the study of acid deposition and its relation to air pollution.

Link to website source:
http://nfwatershed.org/templates/System/details.asp?id=40322&PID=490669

ISOPACH MAP

An isopach map displays the stratigraphic thickness of a rock unit and is generally used in geological exploration for oil and for underground structural analysis. This particular isopach map created by the US Geological Survey is part of a reservoir characterization of the House Creek Oil Field, Powder River Basin in Wyoming. It is showing the thickness (in feet) of Sussex "B" sandstone. If I understand the illustration correctly, by looking at the small inset map of oil production, the higher producing wells are located where the sandstone is thicker.

Link to website source:
http://pubs.usgs.gov/dds/dds-033/USGS_3D/ssx_txt/all.htm

ISOHYETS

An isohyet is a line joining points of equal precipitation. This is a very pretty map of Tasmania showing mean annual rainfall in millimeters. It is obvious that rainfall is more concentrated in the southwest part of the state while the southeast is dry and the northeast has one area getting moderate rain. The prevailing wind pattern is from west to east, similar to the U.S., so the moisture is falling before it reaches the east reducing the chances of rain. I would like to see a map of the biomes for this area which are created and impacted by this climatic pattern. The source of this map is the Bureau of Meteorology, Hobart.

Link to website source:
http://soer.justice.tas.gov.au/2003/image/265/index.php

ISOTACHS

I chose this map to illustrate isotachs just because it is terribly obnoxious but does get the message across! The blue lines filled in with bright shades of green and yellow are connecting points of equal wind speed. They are using contours and color to represent the third variable and it certainly shows up on the black background. I did have to take a second look to see what the map was since the states are outlined in a very pale orange color and the white isobars look like they are on top of the other layers. It is interesting how both sets of contour lines follow a similar pattern starting in the north and making a sweep south and back up. This is a pretty neat comparison of the two variables together on a map dated October, 1996.

Link to website source:
http://www.atmos.washington.edu/~mcmurdie/oct96/oct96_labs.html

ISOBARS

This is a fairly simple but good map of Australia illustrating isobars and a few other weather symbols. The black contour lines labeled with numbers are connecting points of equal pressure across the map. The image came from the Australian Government website and is a clean, easy to read, representation of the weather leaving off an unnecessary detail to jumble the map. The little barb like symbols indicate wind direction and speed while the cross hatching reflects rainfall in the past 24 hours. Where the isobars are close together, change in the variable is larger and generally the winds are stronger. Around the high pressure systems the pressure is increasing quickly but around the lows the change is gradual. It looks like the four pressure systems and land mass are greatly influencing the wind patterns.

Link to website source:
http://www.bom.gov.au/info/ftweather/page_7.shtml

LIDAR

LIDAR (light detection and ranging) seems to be the up and coming thing and I am sure this particular image has been used extensively. Most people should recognize the haunting illustration of Ground Zero taken in September 2001. This was a direct result of the terrorist attacks that reduced the World Trade Center to 16 acres of rubble. LIDAR is a remote sensing system using laser, instead of radio or microwave radiation, to collect topographic data. With LIDAR, scientists collect elevation figures and create false color images (not photographs) for visualizing information. Each image pixel represents a data (x,y,z) point that is colored according to its value. The points allow generation of a digital elevation model (DEM) of the ground surface and construction of a complete image.

Link to website source:
http://imaging.geocomm.com/gallery/

DOPPLER RADAR

I chose this Doppler radar, base reflectivity image of Tropical Storm Alberto, June 2006 because of the colorful display and great location. They have used vibrant colors against a very simple background which makes the storm really stand out. Doppler radar is tracking a circular motion in the clouds by pulsing the atmosphere with microwave radiation and measuring attenuation in the return pulse. With this technology they have calculated the size and types of particles in the air and created a color chart to show heavy, moderate, light and very light rainfall. They are also estimating the speed and direction of the air and watching for the possibility of tornadoes.

Link to website source:
http://www.srh.noaa.gov/tlh/wxevents/alberto061306.html

BLACK AND WHITE AERIAL PHOTO

This is an incredible black and white aerial photo of what they called the “Balloon Track Site” in Eureka, California. It was taken in 1952 by Merle Shuster when this facility was a fully operational railroad switching, maintenance and freight yard. This photo was part of a study conducted in 2001 showing evidence that the parcel was at one time a tidal marsh. It is now considered an urban brownfield and part of an environmental restoration project. The clarity and visibility of this “old” photo is amazing and I love black and white.

Link to website source:
http://online.redwoods.edu/instruct/colloquium/0607/

INFRARED AERIAL PHOTO

The colors in this infrared aerial photo of Onondaga Lake and the surrounding area drew my attention to this particular map. Most of the maps I have seen of this type use a similar color scheme but there are usually more pinks and reds reflecting the presence of vegetation. This map has a lot more shades of blue because of the water, streets and buildings in the frame. The city of Syracuse, NY partially surrounds this lake and its large population is evident in the abundance of man-made structures. This aerial is part of a website for The Onondaga Lake Partnership promoting a clean lake and fighting the obvious impact of pollution from the surrounding infrastructure and human intrusion.

Link to website source:
http://www.onlakepartners.org/p1101.html

CARTOGRAPHIC ANIMATION

This particular map is a non-temporal (not representing change over time) cartographic animation of Omaha, Nebraska. It reflects the spatial trend of population based on age groups across the city. Omaha’s early growth happened along the river which is the easterly border giving reason for the higher percentage of older people in this area while the younger ones are in the north and west parts of the city which developed later.

Link to website source:
http://maps.unomaha.edu/mp/Articles/GISLIS/VisAnim.html

NON STATISTICAL MAP

This map reflects the unequal distribution of phone lines around the world. The data is from 1992 and it uses different colors to represent the number of main lines per 100 inhabitants. I imagine the numbers are higher today but the variation between countries would probably be close to the same. This map is part of a minority telecommunications development program dedicated to developing programs and policies that increase minority ownership of broadcast and telecommunications businesses. The map is more clear when you click on it.

Note: I originally had this posted as a statisitcal map but upon further study, I realized, by slide definition, this one is not the type.

Link to website source:
http://www.ntia.doc.gov/opadhome/mtdpweb/outline.htm

CARTOGRAM

This map is a cartogram using population as the variable to determine the size and shape of each county in the Contiguous U.S. The distorted result is overlaid with outlines representing the actual size, shape and location of each county. This is a pretty abstract illustration of the U.S. but it certainly gives you a good picture of how the counties compare to each other in population.

Link to website source:
http://issrweb.asu.edu/services/gis/sample-maps.html

FLOW MAP

This flow map shows migration from other states to California and New York. The flow illustrated by this map reflects more people moving from the East Coast to New York while California attracts people from more geographic regions across the country. It looks like the widths of the lines are in proportion with the larger or smaller number of people migrating from specific places. I would like to see this diagram or some version of it over laid on a map of the US so you could get a better idea about distances.

Link to website source:

http://graphics.stanford.edu/papers/flow_map_layout/

ISOLINE MAP

This is an interesting isoline map from an article published by ESRI about how GIS is being used in education. The isolines represent rainfall ranges in Maui, Hawaii and they are laid over a Landsat image. The range is drastic in some areas and this jpg really demonstrates the affects of rainfall amounts on land cover and use. It is an amazing illustration of how climate impacts the surface of the earth. The isolines just seem to highlight the areas of changing vegetation and color.

Cool map!

Link to website source:
http://www.esri.com/news/arcwatch/0207/feature.html

PROPORTIONAL CIRCLE MAP

This map is an example of a proportional circle map showing population by mother tongue for provinces and territories in Canada. The source is Statistics Canada dated 2006 and the green circles represent a specific number. The size of the circle is relative to the size of the population where a smaller circle symbolizes lower population and a larger one, greater population. This website has a learning resource called E-STAT which is an interactive tool about society and the economy in Canada. Access is free but only available to educational institutions. The map I found is just an example of the mapping tools they offer for analyzing trends across geographic regions.

Link to website source:

http://www.statcan.ca/english/Estat/guide/census.htm