Welcome to the CASA-2 Interactive Carbon Cycle Model

Casa 2 (lite) is an interactive modeling program which will allow you to simulate the carbon cycle in different types of virtual ecosystems with appropriate vegetation, soil, and climatic conditions.  The simulation interface can be divided into two portions: an input panel, which is visible below these instructions, and an output panel created to display the results of a simulation.
The top row of buttons on the input panel allows you to load a pre-configured ecosystem with climatic data - a boreal forest, a tall grassland, or a tropical forest.

The second row of buttons allow you to modify several basic environmental parameters, the vegetation type, the soil texture, and the latitude of the modeling location.

The next four graph areas display various monthly quantities required by the simulation. Each of these graphs can be modified in two ways. To change the value of an individual month, first click on the point - when selected the point should turn green. Then click on another location within the graph window and the point will reposition itself to the vertical position of your click. The vertical location your cursor is currently over is displayed on the left side of the YearGraph. The orange line shows the annual mean of each quantity. The second method to modify the graphs are to use the +/- buttons located to the right of each graph. These buttons will either add or subtract a constant value from every month. At the bottom of the input panel is a large button, the pressing of which executes the modeling program. The results are then placed in a second window.  Some abbreviations to remember,
bulletNPP = Net Primary Productivity
bulletNPPAN = Net Primary Productivity, Annual Sum
bulletPAR = Photosynthetically Active Radiation
bulletfAPAR = Fractional Absorbtion of Photosynthetically Active Radiation (by leaves)
bulletNDVI = Normalized Difference Vegetation Index
bulletLAI = Leaf Area Index
 


 


greg@globalecology.stanford.edu

Last modified: Wed December 17 2001