SLAMM-View Web-Mapping Application
Last Updated Friday August 01, 2008

To go directly to SLAMM-View, click here.

Disclaimer: The SLAMM model simulates the effects of rising sea level on coastal landcover types. It is important to be aware of the limitations of this approach. Model results are predictive forecasts; they may or may not reflect actual conditions in the future.

NOTE: Digital geospatial data from both this GA/SC project and the Chesapeake project (http://www.nwf.org/sealevelrise/chesapeake.cfm) can now be accessed through SLAMM-View. The “base year” for these modeling efforts is 1999 and 1996, respectively.

Background

Getting Started

Feedback

Background

Efficiently and effectively presenting the large volume of geospatially-referenced, gridded data output from the SLAMM model for each sea-level rise (SLR) scenario time-series is a challenge. In this study, an output file was produced for each of 5 different dates in a time-series (i.e., Base Year, 2025, 2050, 2075, and 2100) for each of 3 different scenarios (i.e., A1B Mean, A1B Max, and 1m SLR). When examining these outputs, the logical pairs of these 15 different data layers are “same scenario, different date” and “same date, different scenario” which results in 45 unique combinations.
 

While summary tables provide the means to present SLAMM output in a condensed form, the spatial context of where the changes occur is lost. Maps of the entire study region at a resolution sufficient to examine local impacts are large and unwieldy to place side by side for comparison, especially in digital format. Making the raw, gridded output data publicly-available is not a viable solution for the researcher or layperson lacking GIS skills, GIS software, or persons with those resources but lacking time.

The research team solved this geospatial accessibility problem by developing a web-mapping application named “SLAMM-View”. SLAMM-View portrays pairs of simulation results in conjunction with other thematic layers which provide context. SLAMM-View allows the user to choose one of the 45 output pairs in a dual “live” map display: either from the same year (e.g., 2100) but from different scenarios (e.g., a 0.5 m SLR and a 1 m SLR), or from different years within the same scenario (e.g., base year 2000, and year 2100 under a 1 m SLR). The zooming and panning tools allow the user to focus the inquiry on their particular locality of interest, be it a large region encompassing both Georgia and South Carolina, or a small barrier island. One unique aspect of this web-mapping tool, vital to facilitating a comparison between the selected pair of simulation results, is that the dual maps are geographically-linked: zooming or panning in one map causes an identical action in the other map.

SLAMM-View is a browser-based application that utilizes a combination of server and client software (Java and Java-script) based on Image Matters userSmarts® technology. The ACSII formatted output was converted to PNG (Portable Network Graphics), an extensible file format for the lossless, portable, well-compressed storage of raster images. This provides for fast rendering of the large gridded maps over the Internet without any reduction in the detail when viewed at local scales. The application accesses contextual layers such as state and county boundaries, roads, and NWI wetlands via web mapping services (OGC WMS), with adjustable layer transparency and a layer control view that allows users to order and turn these ancillary layers on and off. SLAMM-View was developed to support Firefox, as well as both Internet Explorer 6 and 7 browsers. Server side software was installed, with support from Joe Rinkovsky and Keith Lehigh of Research Technologies at University Information Technology Services at Indiana University.

Getting Started
 

SLAMM-View can be accessed at: http://discern.uits.iu.edu:8514/slamm-view/.

The SLAMM-View GUI, displayed below, is composed of 4 "views":

• Map Views (top left)

• Map View (top right)

• Comparison / Layers View (bottom left; toggle between co-located Views)

• Legend / Selected Layer View (bottom right; toggle between co-located Views)

For the latter two sets of Views, you can toggle between the co-located Views by clicking the names in the headers.

HELP is found by clicking the Help icon in the Map Toolbar, or the labeled icon in upper right corner of the GUI.

There are three simple steps in getting started with SLAMM-View:

1) Select a Comparison of interest by clicking on the row in the list in the Comparison View.

There are 45 unique combinations, or pairs, from 3 different scenarios each with 5 different dates:

• 15 combinations of same date, different scenario

• 30 combinations of same scenario, different date

When selected (as appears above):

• a combination (the selected row in the list) will be highlighted in blue, and

• the 2 sets of SLAMM output data from the selected pair will populate the Map Views.

2) Pan and Zoom to your area of interest using the Map Tools in the Map View header. 

Click ("depress") the button of the tool of choice to activate the tool, then use the tool.

 3) Turn contextual layers on or off from within the Layers View, or change opacity settings.

1. Click on the Layers View header to switch from the Comparison View.

2. Select the layer by clicking on the row in the list presented in the Layers View (as shown below)

3. Check (or uncheck) the leftmost "Viz"box to turn on (or off) the selected layer.

To change the opacity setting for a layer:

4. Select the layer as in step "b" (above).

5. Click on the Selected Layer View header to switch from the Legend View.

6. Click on the Opacity Level Bar to change from the 1.00 default value.

Feedback

We would appreciate your feedback about SLAMM-View: bugs, suggested enhancements, etc.  Send email to Jeff Ehman (jeffe@imagemattersllc.com).  Feedback on the SLAMM model itself should go to Jonathan Clough (jclough@warrenpinnacle.com).