|| Related articles
on the IMaGe
Animaps IV: Of Time and Place
III: Color Straws, Color Voxels, and Color Ramps.
The University of Michigan
Community Systems Foundation
to original: Caution--browser may crash on loading Java applets.
along the sand
All turn and look
They turn their
They look at the sea
They cannot look
They cannot look in
But when was that
To any watch they
Robert Frost, Neither
out far nor in deep.
Animated maps offer exciting
tracking spatial change over time. In earlier work in this
(see links above), animated maps (or "animaps") were used to track
across the globe, in bee
mite population over time. They were also used as analytic
that could employ surrogate variables to mimic
change over time in variables that were difficult to learn
The introduction of time, through animation, into the mapping process
the user to participate "with" the map in more than a purely passive
two examples are offered below that allow the reader some degree of
with the process. In the first, the reader experiences emotional
involvement only and a downloadable interaction, only; in the second
reader can actually drag elements of the map around on the screen, as
instantaneous interaction achieved directly through the browser.
Mount Everest: Landing and Take-off
Maps showing mountain ranges are often some of the most
read. Tightly spaced contours look like a jumble of spaghetti
communicate effectively only at quite a local scale. The broad
can be difficult to grasp. Consider the following sequence of
of the India/Nepal/China region surrounding Mount Everest. Here
Himalayas come right up against the Gangetic Plain; tightly spaced
give way sharply to no contours at all.
All the maps in the table below are made from files from the
Chart of the World. The contour interval is 1000 feet. The
red dot on the map was placed there at 28 degrees north latitude and
degrees east longitude, the coordinates of Mount Everest given in
World Atlas. That dot appears in all images in this section.
|| The only layers used in this map
are those for contours
from 1000 to 26000 feet along with the country boundary file.
the vertical separation line between tiles and the gaps in contours at
higher elevations. These suggest a lack of information.
||When the layer for glaciers is added some of the
||When the layer for perennial streams is added the
information is not filled in. Extra information and extra clutter
||Taking a closer look (1:2,500,000) one can separate
some of the contours;
others still are clumped.
||Taking an even closer look (1:1,000,000) permits
of all contours but at the expense of any broad view of the mountain
irregular networks (TINs) are one way to bring some degree of
order into maps with tightly spaced contours. The table below
a TIN for each of the maps in the table above. They were made in
ArcView 3.2 with both Spatial Analyst and 3D Analyst Extensions
The shading ramp employed was one of the default hypsometric set of
(The reader should note that even though these are "standard" in some
green does not necessarily mean that there is lush vegetation nor does
brown necessarily mean that there is dry, barren land.)
||TIN based on the contours; the gaps in the contours
appear as unusually
steep slopes in the associated TIN (as at the right of the map).
||Glacier pattern covers some of the contour gaps and
||Streams added to the TIN cover it up a bit too much
at this scale.
||A closer view shows streams filling swales, as one
||In an even closer view some of the finer triangular
the TIN become evident.
At a broad scale these have the advantage of offering some
little was discernible with contours alone or with contours and other
To get both Frost's close-up and far-out view--to look both
and in deep--animate the TINs.
The animation above is formed from a sequence of 100 TINs of
The single images range in scale from 1:5,000,000 to 1:100,000 with
captured at intervals of 100,000 change in the scale. There are
images in the landing on Mount Everest sequence and 50 images in
off from Mount Everest sequence. The red dot is fixed; it appears
to move because, with scale change, the glacier background pattern is
size and the pattern within it is changing position in relation to the
fixed red dot.
In previous animaps, change was displayed on a
Thus, clustering of regions on the map became apparent over a number of
time periods. What did not become apparent was clustering of
in time. Such clustering can be important if one is looking for
to intervene in the diffusion process; choke-points provide an
to introduce innovations that can control or enhance the diffusion
A relatively new graphical device, a Java applet (Java is a trademark
Sun Microsystems), offers an exciting way to display change over time
reveals clusters of information in a graphically dynamic manner, much
one might imagine in watching the accelerated growth pattern of grape
on a vine.
Thus, the "Mapplet" below offers a
perspective on the varroa
mite data set. That data set shows easily that there is one country
reporting the mite in 1904; in 1912 there is a siting in one other
This sort of sporadic siting, one country at a time, occurs until
Post-1963 there are multiple countries that come in on a yearly
sometimes 3 new additions, sometimes 7 new additions. The pattern
of new receptors may show cycles; indeed, experts on the mites might
on whether or not the graphical pattern on number of new countries by
corresponds in any way to various biological cycles associated with the
mite or its host. If it does, then choke-points in the pattern
possible timing opportunities to intervene (Arlinghaus and
If it does not, then one might consider the extent to which there is
pattern in reporting error or in shipping (http://www.agric.wa.gov.au:7000/ento/bee.htm)and
travel patterns. A glance at the maps
suggests that those who live in as yet unaffected regions might find
observations of particular interest.
In the Mapplet below, the pattern of
sitings from multiple national sources starts just after 1963:
the red color of 1963, as the pattern initiator. The next siting
of the mites occurred in 1967, in four different countries: hence
the entries of 67a, 67b, 67c, and 67d. In 1968 there were also
sitings; thus, another four boxes, 68a, 68b, 68c, 68d. The 1963
is joined to each of 67a, 67b, 67c, and 67d using a length of line
four times as long as the lengths from each of 67a, 67b, 67c, and 67d
each of 68a, 68b, 68c, and 68d. Variation in time between sitings
is represented by varying the length of line joining them. All
in year X are joined to all sitings in year X+1 (or the next year in
sitings occurred). The rationale for joining all from one year to
all in the next year is that one does not know how the diffusion is
place. What is interesting here, perhaps, is that even when there
are years with relatively large numbers of countries reporting sitings,
still the pattern settles back to a small number eventually even though
one might expect it simply to spread even more. Two obvious
to interpret this involve reporting error or some sort of saturation of
the diffusion, perhaps related to forces such as human travel patterns
or mite biology, that are outside the simple mechanics of diffusion
The Mapplet can suggest directions for research questions.