;;types of carbon that are put into the atmosphere
 breed [ EmissionsC ]
 breed [ Ocean-RespirationC]
 breed [ Landplant-RespirationC ]
 breed [ Landsoil-RespirationC ]
 breed [ AtmosphereC ] ;; the pool of carbon we need to count
 breed [OceansurfaceC]
 turtles-own [land? air? ocean? oceansurface? sediment? ]
 globals [ 
  ;;sources of carbon
  Landplant-Respiration   Landsoil-Respiration  Ocean-Respiration  atmospherec-initial atmospherec-post  atmosphere-change
  oceansurfacec-current  pHinitial pH Calcium-Shelled_Organismsnew   oceanabsorption   Landplant-Biomasschange Landplant-Biomassinitial 
  
  ;;pools of carbon
  Oceandeep-C Landdeep-C Landfossil-C Landsoil-C  Oceansediment-C    Atmosphere-C  Landplant-Biomass  ;; Ocean-Biomass Ocean-Biomass-Current
  
  ;;sinks
  Ocean-Photosynthesis Landplant-Photosynthesis
 
  ;; used by the program
  year 
  
    ]
patches-own [ atmosphere? ]

to setup2010 
  ca
  color-patches
     ;; initialize carbon pools and exchanges
  set Ocean-Photosynthesis 60 + ( 60 * (Add_Ocean_Photosynthesizers / 100 ) )
  set Ocean-Respiration 60
  ;; set Ocean-Biomass 1000 ;; measured in megatons, not gigatons!!!!!!!!!!!!!!!!!!!!!
  set Landplant-Biomass (550 + (Add_Forest * 0.0175)) 
  set Landplant-Biomassinitial Landplant-Biomass
  set Landsoil-Respiration ((550 / Landplant-Biomass) * 60 ) 
  set Landdeep-C 0  set Landfossil-C 10000 set Landsoil-C 2300  
  set Oceandeep-C 3700   
  ask patch 0 15 [ sprout-AtmosphereC 800 [ set shape "tinydot" set color blue + 3  set heading 180 set air? true set ocean? false set sediment? false] ]
  ask patch 19 4 [ sprout-OceansurfaceC 1000 [ set shape "tinydot" set color blue - 2  set air? false  set ocean? false set land? false set oceansurface? true set sediment? false ] ]
  set year 2010
  set oceansurfacec-current  count  turtles-on patches with [ pcolor =  blue + 1 ]
  set atmospherec-initial 800
  set pHinitial 8.14
  set pH pHinitial
  set Landplant-Biomass (Landplant-Biomass - (Landplant-Biomass * ( %_of_forest_cleared_yearly / 100))) 
  do-plots
end

to setup1710
  ca
  color-patches
      ;; initialize carbon pools and exchanges
  set Ocean-Photosynthesis 60 + ( 60 * (Add_Ocean_Photosynthesizers / 100 ) )
  set Ocean-Respiration 60
  ;; set Ocean-Biomass 1000 ;; measured in megatons, not gigatons!!!!!!!!!!!!!!!!!!!!!
  set Landplant-Biomass (700 + (Add_Forest * 0.0175)) 
  set Landplant-Biomassinitial Landplant-Biomass
  set Landsoil-Respiration ((700 / Landplant-Biomass) * 60 ) 
  set Landdeep-C 0  set Landfossil-C 10000 set Landsoil-C 2300  
  set Oceandeep-C 3700   
  ask patch 0 15 [ sprout-AtmosphereC 660 [ set shape "tinydot" set color blue + 3  set heading 180 set air? true set ocean? false set sediment? false] ]
  ask patch 19 4 [ sprout-OceansurfaceC 900 [ set shape "tinydot" set color blue - 2  set air? false  set ocean? false set land? false set oceansurface? true set sediment? false ] ]
  set year 1710
  set oceansurfacec-current  count  turtles-on patches with [ pcolor =  blue + 1 ]
  set atmospherec-initial 660
  set pHinitial 8.25
  set pH pHinitial
  set Landplant-Biomass (Landplant-Biomass - (Landplant-Biomass * ( %_of_forest_cleared_yearly / 100))) 
  do-plots
end

to color-patches
ask patches [
    if pycor < -8 and pxcor < -9  [set pcolor white set atmosphere? false ] ;; landdeep 
    if pycor < 2 and pycor >= -8 and pxcor < -9 [set pcolor brown - 3  set atmosphere? false ];; landfossil
    if pycor < 4  and pycor >= 2 and pxcor < -9 [set pcolor brown - 2 set atmosphere? false ];; landsoil
    if pycor = 4 and pxcor = 15 [ set pcolor brown - 2 set atmosphere? false ]
    if pycor < 5 and pycor >= 4  and pxcor < -9 [set pcolor green  set atmosphere? false ] ;; landplants 
    if pycor < 6 and pycor >= 5   and pxcor < -28 and pxcor > -30 [set pcolor green set atmosphere? false ] ;; tree
    if pycor < 6 and pycor >= 5   and pxcor < -26 and pxcor > -28 [set pcolor green  set atmosphere? false ] ;; tree
    if pycor = 4 and pxcor = -15 [ set pcolor brown - 2 set atmosphere? false ]
    if pycor < -12 and pxcor >= -9 [set pcolor brown + 2 set atmosphere? false ] ;; oceansediment
    if pycor < 4 and pycor >= -12 and pxcor >= -9 [set pcolor blue - 1  set atmosphere? false];; oceandeep
    if pycor < 5 and pycor >= 4 and pxcor >= -9 [set pcolor blue + 1 set atmosphere? false ] ;; oceansurface
    if pycor >= 5  [set pcolor blue + 3  set atmosphere? true ];; atmosphere 
    if pycor < 6 and pycor >= 4   and pxcor < -18 and pxcor > -23 [set pcolor black set atmosphere? false ] ;; emissions 
    if pycor < 9 and pycor >= 6   and pxcor < -21 and pxcor > -23 [set pcolor black   set atmosphere? false ] ;; smoke stack
  ] end

to go
 if ( ticks = years + 1 ) [ stop ]
 set atmospherec-initial  count turtles-on patches with [ pycor > 4 ]
 set Landplant-Biomassinitial Landplant-Biomass
 set Landplant-Biomass ( Landplant-Biomass - ( Landplant-Biomass * ( %_of_forest_cleared_yearly / 100)))
 set Landplant-Biomasschange ( Landplant-Biomassinitial - Landplant-Biomass)
    ;;; plant Resp
 ask patch -27 5  [sprout-Landplant-RespirationC   Landplant-Biomasschange
     [set shape "tinydot" set color yellow  set heading 0 fd 1  set air? false set land? true set oceansurface? false set sediment? false ]] 
   ;;; ocean Resp
 ask patch 23 5  [sprout-Ocean-RespirationC  Ocean-Respiration 
     [set shape "tinydot" set color black  set heading 0 fd 1  set air? false set land? false set oceansurface? false set ocean? true set sediment? false ] ]
   ;; factory 
 ask patch -22 8 [sprout-EmissionsC  Emissions [set shape "factory" set size .5 set color black  set heading 0 fd 1 set air? false set land? true
      set oceansurface? false set sediment? false ] ]
    ;;; half of plant resp 
 ask patch -29 5  [sprout-Landplant-RespirationC  0.5 *  .1 *   Landplant-Biomass [set shape "tinydot" set color black set heading 0 fd 1
      set air? false set land? true set oceansurface? false set sediment? false ] ] 
       ;;; half of plant resp
 ask patch -27 5  
     [sprout-Landplant-RespirationC 0.5 * .1 * Landplant-Biomass [set shape "tinydot" set color black  set heading 0 fd 1 set air? false set land? true
          set oceansurface? false set sediment? false ] ]   
  ask patch -15 4  ;;; soil resp
    [sprout-Landsoil-RespirationC   Landsoil-Respiration * ( Landplant-Biomassinitial / Landplant-Biomass  ) [set shape "tinydot" set color black
      set heading 0 fd 1 set air? false set land? true set oceansurface? false set sediment? false ] ]
      
      
      ;;carbon sinks
      
  ask  n-of ( .2 * Landplant-Biomass  )  turtles with [ ycor > 4 ] [ die ]   ;n-of  ( 0.2 * Landplant-Biomass ) 
           ;; if year = 2010 and Landplant-Biomass < Landplant-Biomass-Max [ set Landplant-Biomass Landplant-Biomass + (  .3 * emissions) ];; not using -max anymore
           ;; if year = 2010  [ set Landplant-Biomass ( Landplant-Biomass + (  .3 * emissions ))  ];; not using -max anymore
  let greaterthan3 ( emissions - 3 )
  let atmosphericc ( count turtles-on patches with [ pycor > 4 ] )
  if ( year = 2010  and  greaterthan3 <= 0 ) [ ask n-of ( ( .3 * emissions ) * (Landplant-Biomass / 550 * ( atmosphericc / 1000 ))) turtles with [ pycor > 4 ] [ die ] ]
  if (year = 1710) [ set Landplant-Biomass ( Landplant-Biomass - ( .3 * emissions)) ] ;; burning wood and other deforestation
     
      ;; set Ocean-Photosynthesis ((Ocean-Biomass-Current / 16.666666) * ( oceansurfacec-current / 1000 ))
      ;; set Ocean-Respiration (Ocean-Biomass-Current / 16.666666)
      ;; if  ( Add_Ocean_Photosynthesizers > 0 ) [  ask n-of ((Ocean-Biomass-Current - Ocean-Biomass ) * .12 ) turtles-on patches with [ pcolor = blue + 1 ] [die ] ] 
      ;;;; I use * .12 because ratio of landplants/ocean and ratio of land PS/ ocean ps (ocean appears 12 times more efficient :) !
      ;; if ( Add_Ocean_Photosynthesizers < 0 ) [ ask patch -9 4 [ sprout-OceansurfaceC ((Ocean-Biomass - Ocean-Biomass-Current ) * .12 ) 
      ;; [ set shape "tinydot" set size 1.5 set color white set air? false set land? false set oceansurface? true set sediment? false ] ] ]
      ;; set Ocean-Biomass Ocean-Biomass-Current
              
    set atmospherec-post  count turtles-on patches with [ pycor > 4 ]
    if ( ticks > 0) [ set atmosphere-change (((  atmospherec-post - atmospherec-initial) / ( atmospherec-initial)) / 10 ) ] ;; I hate the 1.1 fudge factor (it's gone)
           ;; anthropogenic C has increased ocean C by only 1-2%, though it is has increased atmospheric C by about 38%. see hall 2009.  see also Revelle Buffer Effect.
           ;; but that's ppm.  what about net in GT?  that's up about 21%
    set oceanabsorption ( atmosphere-change * oceansurfacec-current)
          ;; if ( oceanabsorption < ( .01 * oceansurfacec-current ) ) [set oceanabsorption ( .01 * oceansurfacec-current ) ];; rounds up small numbers
    let ratio ( oceansurfacec-current / atmosphericc )
    if ( ratio > 1.2 ) [ ask n-of ( oceanabsorption  ) turtles with [ pycor = 4 ] [ set ycor 5 + random 9 set air? true set oceansurface? false] ]
    if ( ratio < ( .8 *  ( count turtles-on patches with [ pycor > 4 ] ) )) [ set oceanabsorption .01 * oceansurfacec-current ]
       
    if ( atmosphere-change > 0 ) 
       [ask n-of oceanabsorption turtles with [ pycor > 4 ] [  setxy ( 30 - random 21 )  4  set shape "factory" set size .5 set color blue - 1 set heading 90 
       set air? false  set ocean? false set land? false set oceansurface? true set sediment? false ] ] 
       
    if ( atmospherec-initial  > .8 *  oceansurfacec-current) 
       [ask n-of ( 0.02 *  atmospherec-initial ) turtles with [ pycor > 4 ] [  setxy ( 30 - random 21 )  4  set shape "factory" set size .5 set color blue - 1 set heading 90 
       set air? false  set ocean? false set land? false set oceansurface? true set sediment? false ] ] 
       
    if ( atmospherec-initial  < .8 *  oceansurfacec-current) 
      [ ask n-of ( 0.02 *  oceansurfacec-current ) turtles with [ pycor = 4 ] [ set ycor 5 + random 9 set air? true set oceansurface? false] ]
  
    if ( Add_Every_Year = true ) [ set  Ocean-Photosynthesis ( Ocean-Photosynthesis + ( 60 * (Add_Ocean_Photosynthesizers / 100 ) ))]
    if ( year = 2010) [ ask n-of  ( Ocean-Photosynthesis  * ( oceansurfacec-current / 1000 ) )  turtles with [ ycor > 4 ] [ die ]]
    if ( year = 1710 ) [ask n-of  ( Ocean-Photosynthesis  * ( oceansurfacec-current / 900 ) )  turtles with [ ycor > 4 ] [ die ]]
       
       set pH ((-0.0011 * oceansurfacec-current )+ 9.24 )

    if ( oceansurfacec-current >= 900 ) [ set Calcium-Shelled_Organismsnew (Calcium-Shelled_Organisms * ( 900  / oceansurfacec-current  ) ) ]  ;; Calcification changed to Calcium-Shelled_Organisms  
    if ( oceansurfacec-current < 900 ) [  set Calcium-Shelled_Organismsnew Calcium-Shelled_Organisms ]
    ask n-of ( Calcium-Shelled_Organismsnew  ) turtles with [ oceansurface? = true ] [ setxy (3 + random 26) (-15 + random 3 ) 
       set shape "coccolithophore" set color white set size 1 set land? false set ocean? false set air? false set oceansurface? false set sediment? true ]
       
   set oceansurfacec-current count  turtles-on patches with [ pcolor =  blue + 1 ]
   ask turtles [ move-carbon ]
   do-plots

   end

 to move-carbon 
  if (land? = true)  [set heading heading - (0 - random 10) fd 1]
  if (ocean? = true) [set heading heading + (0 - random 10) fd 1]
  if (air? = true) [set heading heading - (180 - random 10) fd 1]
  if (oceansurface? = true) [ setxy ( -9 + random 39)  4  ]
  if (ycor > 14) [ set ycor (11 - random 3) ]
  
  ;; stopping wrap-around above water
  if (xcor > 29) and ycor >= 5  [set xcor 29 - random 20]  
  if (xcor < -29) [set xcor -29 + random 20]
  if (oceansurface? = false) and ( ycor < 6) and ( sediment? = false ) [set ycor 6 + random 8 ]
 end

  to do-plots
   set-current-plot "Atmospheric and Ocean Surface Carbon"
   set-current-plot-pen "AtmosphereC"
   plot  count turtles-on patches with [ pycor > 4 ]
   set-current-plot-pen "OceanSurfaceC"
   plot  oceansurfacec-current
  
  set-current-plot "Ocean pH" 
  set-current-plot-pen "pH"
  plot   pH
    
    if ( ticks > 0) [ set atmosphere-change (((  atmospherec-post - atmospherec-initial) / ( atmospherec-initial))* 1.1  ) ] ;; I hate the 1.1 fudge factor (it's gone)
          ;; anthropogenic C has increased ocean C by only 1-2%, though it is has increased atmospheric C by about 38%. see hall 2009.  see also Revelle Buffer Effect.
               ;; but that's ppm.  what about net in GT?  that's up about 21%
         ;; if (atmospherec-post > atmospherec-initial)  [ ask n-of (oceansurfacec-change)  turtles with [ ycor > 4 ] 
         ;; [ setxy ( -9 + random 20) 4 set shape "star" set size 2   set air? false  set ocean? false set land? false set oceansurface? true set sediment? false] ]
 
  wait .02  ;; slow the iterations if desired
   tick
  
 end

            ;; watch button watch one-of EmissionsC ;; with [  ]
@#$#@#$#@
GRAPHICS-WINDOW
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BUTTON
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100
2010 levels
setup2010
NIL
1
T
OBSERVER
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NIL
NIL
NIL

BUTTON
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155
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run/stop
go
T
1
T
OBSERVER
NIL
NIL
NIL
NIL

SLIDER
56
121
161
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emissions
emissions
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1.5
.5
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NIL
HORIZONTAL

SLIDER
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213
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Calcium-Shelled_Organisms
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.25
1
NIL
HORIZONTAL

PLOT
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Atmospheric and Ocean Surface Carbon
Years
GigaTons of C
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500.0
1500.0
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PENS
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"OceanSurfaceC" 1.0 0 -13345367 true

BUTTON
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67
213
100
1710 levels
setup1710
NIL
1
T
OBSERVER
NIL
NIL
NIL
NIL

SLIDER
24
175
196
208
years
years
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300
300
1
1
NIL
HORIZONTAL

MONITOR
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437
788
482
Gigatons of Carbon in the Atmosphere
count  turtles-on patches with [ pycor > 4 ]
1
1
11

MONITOR
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437
566
482
Gigatons of Carbon in the Upper Ocean
count turtles with [ pcolor = blue + 1]
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MONITOR
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Gigatons of Carbon in Plants
Landplant-Biomass 
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11

SLIDER
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%_of_forest_cleared_yearly
%_of_forest_cleared_yearly
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0
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HORIZONTAL

SLIDER
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301
429
Add_Ocean_Photosynthesizers
Add_Ocean_Photosynthesizers
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0
.5
1
Percent
HORIZONTAL

PLOT
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Ocean pH
Years
pH
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"pH" 1.0 0 -2674135 true

MONITOR
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pH
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SLIDER
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392
Add_Forest
Add_Forest
0
8000
0
5
1
Thousand square KM
HORIZONTAL

TEXTBOX
73
497
990
567
In 2010, you start with a base of 550 Gigatons of Carbon in Plants.  You can add forest in units of thousands of square Kilometers.  The forest you add is typical of a mixed forest in New Jersey in terms of the Carbon it contains in trees. As long as emissions are occurring and deforestation is not, the amount of Carbon in plants increases every year.  This is because some part of the emissions are being turned into the growth of plants.\nIn 1710, you start with a base of 700 Gigatons of Carbon in Plants.  You cannot add forest in 1710, and the amount of forest decreases automatically.  The rate of decrease is related to the rate of emissions
11
0.0
1

SWITCH
302
396
451
429
Add_Every_Year
Add_Every_Year
1
1
-1000

BUTTON
550
568
719
601
NIL
watch one-of EmissionsC
NIL
1
T
OBSERVER
NIL
NIL
NIL
NIL

@#$#@#$#@
WHAT IS IT?
-----------
Carbon Cycle models the fast carbon cycle. The model is intended to examine the effect of human activities on the amount of Carbon in the atmosphere and the upper ocean. Carbon is reported in gigatons.  Upper ocean pH is shown.

The model can be initialized to two settings:  One represents conditions in 2010; the other represents pre-industrial conditions.  The 2010 setting allows for growth of terrestrial biomass.  Terrestrial biomass decreases in the 1710 scenario to simulate deforestation for fuel and agriculture.  

HOW IT WORKS
------------
Carbon reservoirs and fluxes, especially for the 2010 scenario, are based on the diagram at http://earthobservatory.nasa.gov/Features/CarbonCycle/ (except that I used a terrrestrial plant biomss of 600).  The size of the reservoirs are roughly proportionate to the values given in the diagram, although the Deep ocean is somewhat smaller than it should be.

The pools of Carbon monitored are the atmosphere, the upper ocean, and the deposition of calcium-shelled organisms.  The sources of Carbon are: emissions, ocean photosynthesis, and land plant (forest) photosynthesis.  Land plant photosynthesis and respiration are proprtional to land plant biomas. 
Sinks include ocean respiration, landplant respiration, soil respiration, and tree growth. Soil respiration increases as forest is removed. Calcium-shelled organisms is the long-tern sink of carbon in this model.  The amount of calcification can be adjusted, but it is also automatically affected by the concentration of Carbon in the upper ocean. The object that sinks to indicate calcification is a coccolithophore!   

The absorption of Carbon by the ocean is affected by the ratio of Carbon in the ocean surface over the ratio of Carbon in the atmsophere.  Carbon can go in either direction depending on this ratio.  I used 8/10 as a base ratio.  

HOW TO USE IT
-------------
Use the diagram at http://earthobservatory.nasa.gov/Features/CarbonCycle/ as a reference.
Forest can be added to the initial land plant biomass.  Ocean photosynthesis can be increased initially or yearly.
Hints:
If you have difficulty adjusting a slider to an exact value, you can right click it to edit it and type in the value you desire.

THINGS TO NOTICE
----------------
You can make the model crash by adjusting the value of a variable higher or lower.  What happens to cause the crash? 
Output of emissions is given the shape of little factories.  Once in the atmosphere, all carbon has the same probability of being removed by photosynthesis or absorption by the ocean.  Once in the ocean, it has the same probability of any carbon there of being sequestered by calcification.

THINGS TO TRY
-------------
Try to determine what average yearly emissions are necessary to transform the 1710 world to the 2010 world.  Also try to develop various scenarios to mitigate the current Carbon problem.  Calcification and terrestrial biomass growth can be manipulated for this purpose

EXTENDING THE MODEL
-------------------
A problem to overcome:  under low emissions and high absorption, the ocean becomes depauperate of Carbon.  I neede a feedback to return Carbon sequested in biomass and sedimentation.

NETLOGO FEATURES
----------------

RELATED MODELS
--------------
Watercycle; Global Carbon Cycle; Greenhouse Effect

CREDITS AND REFERENCES
----------------------
http://earthobservatory.nasa.gov/Features/CarbonCycle/ 
http://www.climate.gov/#climateWatch
U.S. DOE. 2008. Carbon Cycling and Biosequestration: Report from the March 2008 Workshop, DOE/SC-108, U.S. Department of Energy Office of Science (http://genomicscience.energy.gov/carboncycle/report/). 
IPCC, 2000 - Nebojsa Nakicenovic and Rob Swart (Eds.) 
Cambridge University Press, UK. pp 570
IPCC, 2007: Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri, R.K and Reisinger, A. (eds.)]. IPCC, Geneva, Switzerland, 104 pp.
Climate Change 2001: The Physical Science Basis, Summary for Policymakers, IPCC
Hall, T/ 2008. Can Ocean Carbon Uptake Keep Pace with Industrial Emissions?
http://www.giss.nasa.gov/research/briefs/hall_03/

http://www.waterencyclopedia.com/Bi-Ca/Carbon-Dioxide-in-the-Ocean-and-Atmosphere.html
Much of the coding was adapted from Watercycle.nlogo, so I thank that anonymous modeler.

Holian, Gary, Andrei P. Sokolov and Ronald G. PrinnUncertainty in Atmospheric CO2 Predictions from a Parametric Uncertainty Analysis of a Global Ocean Carbon Cycle Model
Report No. 80 September 2001
http://web.mit.edu/globalchange/www/MITJPSPGC_Rpt80.pdf

Keith, H., Mackey, B. G. & Lindenmayer, D. B. 2010 Re-evaluation of forest biomass carbon
stocks and lessons from the world’s most carbon-dense forests. Proc. Natl Acad. Sci. USA
106, 11 635–11 640. (doi:10.1073/pnas.0901970106)
@#$#@#$#@
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Polygon -7500403 true true 150 0 135 45 120 75 120 120 105 150 90 180 210 180 195 135 180 105 165 45 150 0

face happy
false
0
Circle -7500403 true true 8 8 285
Circle -16777216 true false 60 75 60
Circle -16777216 true false 180 75 60
Polygon -16777216 true false 150 255 90 239 62 213 47 191 67 179 90 203 109 218 150 225 192 218 210 203 227 181 251 194 236 217 212 240

face neutral
false
0
Circle -7500403 true true 8 7 285
Circle -16777216 true false 60 75 60
Circle -16777216 true false 180 75 60
Rectangle -16777216 true false 60 195 240 225

face sad
false
0
Circle -7500403 true true 8 8 285
Circle -16777216 true false 60 75 60
Circle -16777216 true false 180 75 60
Polygon -16777216 true false 150 168 90 184 62 210 47 232 67 244 90 220 109 205 150 198 192 205 210 220 227 242 251 229 236 206 212 183

factory
false
0
Rectangle -7500403 true true 76 194 285 270
Rectangle -7500403 true true 36 95 59 231
Rectangle -16777216 true false 90 210 270 240
Line -7500403 true 90 195 90 255
Line -7500403 true 120 195 120 255
Line -7500403 true 150 195 150 240
Line -7500403 true 180 195 180 255
Line -7500403 true 210 210 210 240
Line -7500403 true 240 210 240 240
Line -7500403 true 90 225 270 225
Circle -1 true false 37 73 32
Circle -1 true false 55 38 54
Circle -1 true false 96 21 42
Circle -1 true false 105 40 32
Circle -1 true false 129 19 42
Rectangle -7500403 true true 14 228 78 270

fish
false
0
Polygon -1 true false 44 131 21 87 15 86 0 120 15 150 0 180 13 214 20 212 45 166
Polygon -1 true false 135 195 119 235 95 218 76 210 46 204 60 165
Polygon -1 true false 75 45 83 77 71 103 86 114 166 78 135 60
Polygon -7500403 true true 30 136 151 77 226 81 280 119 292 146 292 160 287 170 270 195 195 210 151 212 30 166
Circle -16777216 true false 215 106 30

flag
false
0
Rectangle -7500403 true true 60 15 75 300
Polygon -7500403 true true 90 150 270 90 90 30
Line -7500403 true 75 135 90 135
Line -7500403 true 75 45 90 45

flower
false
0
Polygon -10899396 true false 135 120 165 165 180 210 180 240 150 300 165 300 195 240 195 195 165 135
Circle -7500403 true true 85 132 38
Circle -7500403 true true 130 147 38
Circle -7500403 true true 192 85 38
Circle -7500403 true true 85 40 38
Circle -7500403 true true 177 40 38
Circle -7500403 true true 177 132 38
Circle -7500403 true true 70 85 38
Circle -7500403 true true 130 25 38
Circle -7500403 true true 96 51 108
Circle -16777216 true false 113 68 74
Polygon -10899396 true false 189 233 219 188 249 173 279 188 234 218
Polygon -10899396 true false 180 255 150 210 105 210 75 240 135 240

house
false
0
Rectangle -7500403 true true 45 120 255 285
Rectangle -16777216 true false 120 210 180 285
Polygon -7500403 true true 15 120 150 15 285 120
Line -16777216 false 30 120 270 120

leaf
false
0
Polygon -7500403 true true 150 210 135 195 120 210 60 210 30 195 60 180 60 165 15 135 30 120 15 105 40 104 45 90 60 90 90 105 105 120 120 120 105 60 120 60 135 30 150 15 165 30 180 60 195 60 180 120 195 120 210 105 240 90 255 90 263 104 285 105 270 120 285 135 240 165 240 180 270 195 240 210 180 210 165 195
Polygon -7500403 true true 135 195 135 240 120 255 105 255 105 285 135 285 165 240 165 195

line
true
0
Line -7500403 true 150 0 150 300

line half
true
0
Line -7500403 true 150 0 150 150

pentagon
false
0
Polygon -7500403 true true 150 15 15 120 60 285 240 285 285 120

person
false
0
Circle -7500403 true true 110 5 80
Polygon -7500403 true true 105 90 120 195 90 285 105 300 135 300 150 225 165 300 195 300 210 285 180 195 195 90
Rectangle -7500403 true true 127 79 172 94
Polygon -7500403 true true 195 90 240 150 225 180 165 105
Polygon -7500403 true true 105 90 60 150 75 180 135 105

plant
false
0
Rectangle -7500403 true true 135 90 165 300
Polygon -7500403 true true 135 255 90 210 45 195 75 255 135 285
Polygon -7500403 true true 165 255 210 210 255 195 225 255 165 285
Polygon -7500403 true true 135 180 90 135 45 120 75 180 135 210
Polygon -7500403 true true 165 180 165 210 225 180 255 120 210 135
Polygon -7500403 true true 135 105 90 60 45 45 75 105 135 135
Polygon -7500403 true true 165 105 165 135 225 105 255 45 210 60
Polygon -7500403 true true 135 90 120 45 150 15 180 45 165 90

square
false
0
Rectangle -7500403 true true 30 30 270 270

square 2
false
0
Rectangle -7500403 true true 30 30 270 270
Rectangle -16777216 true false 60 60 240 240

star
false
0
Polygon -7500403 true true 151 1 185 108 298 108 207 175 242 282 151 216 59 282 94 175 3 108 116 108

target
true
0
Circle -7500403 true true 0 0 300
Circle -16777216 true false 30 30 240
Circle -7500403 true true 179 44 122
Circle -16777216 true false 210 75 60
Circle -7500403 true true 104 -1 122
Circle -16777216 true false 135 30 60
Circle -7500403 true true 89 89 122
Circle -16777216 true false 120 120 60
Circle -7500403 true true 164 119 122
Circle -16777216 true false 195 150 60
Circle -7500403 true true 119 179 122
Circle -16777216 true false 150 210 60
Circle -7500403 true true 29 14 122
Circle -16777216 true false 60 45 60
Circle -7500403 true true -16 104 122
Circle -16777216 true false 15 135 60
Circle -7500403 true true 29 164 122
Circle -16777216 true false 60 195 60

tinydot
false
15
Circle -1 true true 135 135 30

tree
false
0
Circle -7500403 true true 118 3 94
Rectangle -6459832 true false 120 195 180 300
Circle -7500403 true true 65 21 108
Circle -7500403 true true 116 41 127
Circle -7500403 true true 45 90 120
Circle -7500403 true true 104 74 152

triangle
false
0
Polygon -7500403 true true 150 30 15 255 285 255

triangle 2
false
0
Polygon -7500403 true true 150 30 15 255 285 255
Polygon -16777216 true false 151 99 225 223 75 224

truck
false
0
Rectangle -7500403 true true 4 45 195 187
Polygon -7500403 true true 296 193 296 150 259 134 244 104 208 104 207 194
Rectangle -1 true false 195 60 195 105
Polygon -16777216 true false 238 112 252 141 219 141 218 112
Circle -16777216 true false 234 174 42
Rectangle -7500403 true true 181 185 214 194
Circle -16777216 true false 144 174 42
Circle -16777216 true false 24 174 42
Circle -7500403 false true 24 174 42
Circle -7500403 false true 144 174 42
Circle -7500403 false true 234 174 42

turtle
true
0
Polygon -10899396 true false 215 204 240 233 246 254 228 266 215 252 193 210
Polygon -10899396 true false 195 90 225 75 245 75 260 89 269 108 261 124 240 105 225 105 210 105
Polygon -10899396 true false 105 90 75 75 55 75 40 89 31 108 39 124 60 105 75 105 90 105
Polygon -10899396 true false 132 85 134 64 107 51 108 17 150 2 192 18 192 52 169 65 172 87
Polygon -10899396 true false 85 204 60 233 54 254 72 266 85 252 107 210
Polygon -7500403 true true 119 75 179 75 209 101 224 135 220 225 175 261 128 261 81 224 74 135 88 99

wheel
false
0
Circle -7500403 true true 3 3 294
Circle -16777216 true false 30 30 240
Line -7500403 true 150 285 150 15
Line -7500403 true 15 150 285 150
Circle -7500403 true true 120 120 60
Line -7500403 true 216 40 79 269
Line -7500403 true 40 84 269 221
Line -7500403 true 40 216 269 79
Line -7500403 true 84 40 221 269

x
false
0
Polygon -7500403 true true 270 75 225 30 30 225 75 270
Polygon -7500403 true true 30 75 75 30 270 225 225 270

@#$#@#$#@
NetLogo 4.1.1
@#$#@#$#@
@#$#@#$#@
@#$#@#$#@
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@#$#@#$#@
default
0.0
-0.2 0 0.0 1.0
0.0 1 1.0 0.0
0.2 0 0.0 1.0
link direction
true
0
Line -7500403 true 150 150 90 180
Line -7500403 true 150 150 210 180

@#$#@#$#@
0
@#$#@#$#@