RE: For the GIS SC - RE: First cut at a symbology use case - along with some other thoughts

Sorry about the post to the full EM list, but am still 
having problems posting to emergency-gis :-(

 

Tried sending this yesterday:

 

As a follow-up to our teleconference Tuesday, here is 
a simple use case for the need for a common and consistent set of EM symbology. 
These are just some initial thoughts and are totally open to criticism, 
discussion, enhancement, etc.

 

Before stating the use case, I think that it is beneficial 
to look at the problem statement. I believe that the Kent/FEMA study provides an 
excellent summary of the problem:

Problem Statement: "When it comes to spatial information 
that is needed during a disaster, there is currently no consistent national set 
of map symbols available for the development of hazard and emergency management 
maps. In order to facilitate the exchange of information and data, to promote 
universal understanding of hazardous and vulnerable locations and to adequately 
address communication of mission critical information across agencies, 
jurisdictions, and all levels of public and private sectors, a set of standard 
cartographic symbols needs to be developed and endorsed by the Federal 
Geographic Data Committee (FGDC). The development of standards for hazard 
mapping will strengthen coordination and communication between planners and will 
enhance the ability of emergency managers to better understand information at a 
glance during crucial decision making moments."

Reworded as a Requirement: From an operational 
perspective, this problem can be  re-stated in the form of a requirement: 
"There is a requirement to create a common operational picture. To build 
this operational picture, we need to access spatial and related content from 
many sources but be able to render (symbolize) them in a common consistent 
manner, independent of the data underlying feature classification scheme, 
structure or data model". These are my word.

Leads to a simple use case:

I am an emergency management specialist. An emergency event has occurred in 
my area. The event is the release of toxic fumes from a chemical plant. I need 
to access spatial data from the city, the state, the USGS, and FEMA to create an 
operational picture using commonly known symbology - even though the spatial 
data are being accessed from multiple repositories. This operational picture 
must show streets, buildings, schools, hospitals, day care centers, 
assisted living centers, and other facilities that will require rapid 
evacuation. Most importantly, it must show a plume dispersion pattern. Once 
I create this operational picture, I need to broadcast it to the first 
responders using the same symbology and style, independent of the display 
device.

(Sorry if I mixed a few requirements in with the use case :-) )

In picture form

The following picture depicts the realities of what an EM response team could 
deal with in terms of multi-source information access and fusion. Some content 
is static, some is dynamic. There are multiple jurisdictions. Each jurisdiction 
collects, manages, and symbolizes (portrays) their spatial data a bit 
differently. There is, therefore, an overarching requirement to provide the 
ability to utilize common symbology to enhance communication (by creating a 
common operating picture - or set of pictures). Much of the thinking that went 
into the following diagram resulted from a collaborative effort between the OGC, 
our members, and a number of local jurisdictions in an OGC Interoperability 
Project called CIPI - Critical Infrastructure Protection Initiative.

 

 

And finally, definition of some of the terms 
used.

 

•Feature – earth 
objects/phenomena that are normally represented as graphical point, line, and 
polygon entities 
on a map (e.g., a house, political boundary, or lake) 

•Coverage – a 
feature that associates positions within a bounded space (its spatiotemporal 
domain) 
to feature attribute values (its range)  (e.g., a digital terrain model or image) 

•Symbol – a set of 
predefined graphical representation parameters and/or fixed graphic icons; 
the 
instructions for how vector graphics are to be represented (e.g., 
geometry/graphic, fill, color, stroke, 
font, orientation, size, opacity, etc.); the instructions for how raster 
graphics are to be represented 
(e.g., opacity, R/G/B channel selection, color map, shaded relief, contrast 
enhancements, 
etc.)  

•Style – maps features 
(types, properties and constraints) to one or more parameterized symbols; also the 
properties and rules describing how features are drawn during a graphical 
rendering process 
(e.g., order of layers, associate symbol type X with feature type Y, or how to 
apply 
one or more symbols to drawing a road at its centerline, etc.)