globals [ sky-top ;; y coordinate of top row of sky earth-top ;; y coordinate of top row of earth temperature ;; overall temperature valor ] breed [rays ray] ;; packets of sunlight breed [IRs IR] ;; packets of infrared radiation breed [heats heat] ;; packets of heat energy breed [clouds cloud] clouds-own [cloud-speed cloud-id] ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== breed [CFCs CFC];;DECLARAÇÃO DO GAS CFC NO MODELO breed [suns sun] ;;DECLARAÇÃO DO SOL NO MODELO suns-own [sun-speed];;DECLARAÇÃO DA VELOCIDADE DO SOL NO MODELO breed [factories factory];;DECLARAÇÃO DAS FÁBRICAS DO MODELO breed [ozones ozone] ;;DECLARAÇÃO DAS MOLÉCULAS DE OZONIO breed [houses house] ;;DECLARAÇÃO DAS CASAS DO MODELO ozones-own [ozone-speed] ;; DECLARAÇÃO DA VELOCIDADE DAS MOLÉCULAS NO MODELO ;===================================================================== ;; ;; Setup Procedures ;; to setup clear-all set-default-shape rays "ray" set-default-shape IRs "ray" set-default-shape clouds "cloud" set-default-shape heats "dot" ;set-default-shape CO2s "CO2-molecule" setup-world set temperature 12 reset-ticks ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== set-default-shape CFCs "co2-molecule" ;;CHAMADA DA MOLÉCULA DO GÁS CFC set-default-shape suns "sun";;CHAMADA DO SOL NO MODELO PELO BOTÃO DE SETUP set-default-shape factories "factory" ;; CHAMADO DAS FÁBRICAS NO MODELO set-default-shape ozones "cfc-ozone" ;;CHAMADO DAS MOLÉCULAS DO GÁS OZONIO set-default-shape houses "house";;CHAMADO DAS CASAS NO MODELO set valor 0 ;====================================================================== end to setup-world set sky-top max-pycor - 5 set earth-top 0 ask patches [ ;; set colors for the different sections of the world if pycor > sky-top [ ;; space set pcolor scale-color white pycor 22 15 ] if pycor <= sky-top and pycor > earth-top [ ;; sky set pcolor scale-color blue pycor -20 20 ] if pycor < earth-top [ set pcolor red + 3 ] ;; earth if pycor = earth-top ;; earth surface [ update-albedo ] ] ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== create-suns 1 [ set color yellow set size 4 setxy (min-pxcor + 0.3) 20.5 set heading 90 set sun-speed 0.045 ] ;; CÓDIGO QUE CRIA O SOL E ALTERA CONFIGURAÇÕES DESTE ;====================================================================== end ;; ;; Runtime Procedures ;; to go ask clouds [ fd cloud-speed ] ; move clouds along run-sunshine ;; step sunshine ;; if the albedo slider has moved update the color of the "earth surface" patches ask patches with [pycor = earth-top] [ update-albedo ] run-heat ;; step heat run-IR ;; step IR run-CFC ;; MOVIMENTA AS MOLÉCULAS DE CFC tick ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== ;PEDE PARA AS FÁBRICAS EMITIREM CFC ask factories [ emmit-factory ] ; PEDE PARA O SOL "CORRER" PELO AMBIENTE QUANDO PRESSIONADO O BOTÃO EXECUTAR ask suns [ run-sun ] ;PEDE PARA AS PARTÍCULAS DE OZONIO ANDAREM PELO AMBIENTE ask ozones [ run-ozone ] ;PEDE PARA AS CASAS DO AMBIENTE EMITAM PARTÍCULAS DE CFCs. ask houses [ emmit-house ] ask cfcs [ run-ozone ] ;========================= ============================================ end ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== to run-sun fd sun-speed * 49 / 48 ; CÓDIGO QUE DEFINE A VELOCIDADE DO QUAL O SOL PERCORRE O AMBIENTE end to run-ozone fd .04 ;let dist 12; + random-float 0.1 ;fd dist ; CÓDIGO QUE DEFINE A VELOCIDADE DO QUAL AS PARTÍCULAS DE OZONIO PERCORREM O AMBIENTE end ;===================================================================== ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== to emmit-factory if random 100 > 98 [ hatch-CFCs 1 [ set size 1 set color red ] ] end to emmit-house if random 100 > 80 [ hatch-CFCs 1 [ set size 1 set color red ] ] end ;CÓDIGO QUE EMITE O GÁS CFC NA ATMOSFERA DO AMBIENTE ;==================================================================== to update-albedo ;; patch procedure set pcolor scale-color green albedo 0 1 end to add-cloud ;; erase clouds and then create new ones, plus one let sky-height sky-top - earth-top ;; find a random altitude for the clouds but ;; make sure to keep it in the sky area let y earth-top + (random-float (sky-height - 4)) + 2 ;; no clouds should have speed 0 let speed (random-float 0.1) + 0.01 let x random-xcor let id 0 ;; we don't care what the cloud-id is as long as ;; all the turtles in this cluster have the same ;; id and it is unique among cloud clusters if any? clouds [ set id max [cloud-id] of clouds + 1 ] create-clouds 3 + random 20 [ set cloud-speed speed set cloud-id id ;; all the cloud turtles in each larger cloud should ;; be nearby but not directly on top of the others so ;; add a little wiggle room in the x and ycors setxy x + random 9 - 4 ;; the clouds should generally be clustered around the ;; center with occasional larger variations y + 2.5 + random-float 2 - random-float 2 set color white ;; varying size is also purely for visualization ;; since we're only doing patch-based collisions set size 2 + random 2 set heading 90 ] end to run-sunshine ask rays [ if not can-move? 0.3 [ die ] ;; kill them off at the edge fd 0.3 ;; otherwise keep moving ] create-sunshine ;; start new sun rays from top reflect-rays-from-clouds ;; check for reflection off clouds encounter-earth ;; check for reflection off earth and absorption end to create-sunshine ;; don't necessarily create a ray each tick ;; as brightness gets higher make more if 10 * sun-brightness > random 50 [ create-rays 1 [ set heading 160 set color yellow ;; rays only come from a small area ;; near the top of the world setxy (random 10) + min-pxcor max-pycor ] ] end to reflect-rays-from-clouds ask rays with [any? clouds-here] [ ;; if ray shares patch with a cloud set heading 180 - heading ;; turn the ray around ] end to encounter-earth ask rays with [ycor <= earth-top] [ ;; depending on the albedo either ;; the earth absorbs the heat or reflects it ifelse 100 * albedo > random 100 [ set heading 180 - heading ] ;; reflect [ rt random 45 - random 45 ;; absorb into the earth set color red - 2 + random 4 set breed heats ] ] end to run-heat ;; advances the heat energy turtles ;; the temperature is related to the number of heat turtles set temperature 0.99 * temperature + 0.01 * (12 + 0.1 * count heats) ask heats [ let dist 0.5 * random-float 1 ifelse can-move? dist [ fd dist ] [ set heading 180 - heading ] ;; if we're hitting the edge of the world, turn around if ycor >= earth-top [ ;; if heading back into sky ifelse temperature > 20 + random 40 ;; heats only seep out of the earth from a small area ;; this makes the model look nice but it also contributes ;; to the rate at which heat can be lost and xcor > 0 and xcor < max-pxcor - 8 [ set breed IRs ;; let some escape as IR set heading 20 set color magenta ] [ set heading 100 + random 160 ] ;; return them to earth ] ] end to run-IR ask IRs [ if not can-move? 0.3 [ die ] fd 0.3 if ycor <= earth-top [ ;; convert to heat if we hit the earth's surface again set breed heats rt random 45 lt random 45 set color red - 2 + random 4 ] ;if any? CO2s-here ;; check for collision with CO2 if any? CFCs-here ;; CONFERIR A COLISÃO COM O GÁS CFC [ set heading 180 - heading ] ] end ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== to run-CFC ask CFCs [ rt random 51 - 25 ;; turn a bit let dist 0.05 + random-float 0.1 ;; MANTÉM AS MOLÉCULAS DE CFC NA ÁREA DA ATMOSFÉRA DO AMBIENTE if [not shade-of? blue pcolor] of patch-ahead dist [ set heading 180 - heading ] fd dist ;; move forward a bit ] end ;===================================================================== ;================== MODIFICAÇÃO NO MODELO ORIGINAL==================== to add-factory create-factories 1 [ set color red set size 3.5 setxy random-xcor 1 ] end ;CÓDIGO QUE ADICIONA AS FÁBRICAS NO AMBIENTE to add-ozone create-ozones 1 [ set color 105 set size 1.3 setxy (min-pxcor + 1) 17 set heading 90 ] end ;CÓDIGO QUE ADICIONA AS MOLÉCULAS DE OZÔNIO NA CAMADA SUPERIOR DO AMBIENTE to add-house create-houses 1 [ set color green set size 1.5 setxy random-xcor 1 ] end ;CÓDIGO QUE ADICIONA AS CASAS NO AMBIENTE ;===================================================================== to remove-factory ;; REMOVE UMA FÁBRICA POR VEZ repeat 1 [ if any? factories [ ask one-of factories [ die ] ] ] end ;CÓDIGO QUE REMOVE AS FÁBRICAS DO AMBIENTE to remove-CFC ;; RANDOMICAMENTE REMOVE 25 MOLÉCULAS DE CFC repeat 25 [ if any? CFCs [ ask one-of CFCs [ die ] ] ] end ;CÓDIGO QUE REMOVE AS MOLÉCULAS DE CFC DO AMBIENTE to remove-cloud if any? clouds [ let doomed-id one-of remove-duplicates [cloud-id] of clouds ask clouds with [cloud-id = doomed-id] [ die ] ] end to remove-ozone ;; repeat 1 [ if any? ozones[ ask one-of ozones [ die ] ] ] end ; CÓDIGO QUE REMOVE AS NUVENS DO AMBIENTE ;======================================================================= ; Copyright 2007 Uri Wilensky. ; See Info tab for full copyright and license. @#$#@#$#@ GRAPHICS-WINDOW 317 12 864 362 -1 -1 11.0 1 10 1 1 1 0 1 0 1 -24 24 -8 22 0 0 1 ticks 30.0 BUTTON 6 12 101 45 Preparar setup NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 103 12 198 45 Executar go T 1 T OBSERVER NIL NIL NIL NIL 0 SLIDER 18 47 191 80 sun-brightness sun-brightness 0 5 2.8 0.2 1 NIL HORIZONTAL PLOT 13 251 282 462 Temperatura Global NIL NIL 0.0 10.0 10.0 20.0 true false "" "" PENS "default" 1.0 0 -2674135 true "" "plot temperature" BUTTON 10 192 150 225 Remover CFCs remove-CFC NIL 1 T OBSERVER NIL NIL NIL NIL 0 MONITOR 210 60 299 105 NIL temperature 1 1 11 BUTTON 11 118 149 151 Adicionar Nuvem add-cloud NIL 1 T OBSERVER NIL NIL NIL NIL 0 BUTTON 11 155 150 188 Remover Nuvem remove-cloud NIL 1 T OBSERVER NIL NIL NIL NIL 0 MONITOR 210 108 300 153 Qtd. CFCs count CFCs 2 1 11 BUTTON 315 375 492 409 Trajetória Raio de Calor watch one-of rays\nask subject [ pen-down ] NIL 1 T OBSERVER NIL NIL NIL NIL 0 BUTTON 317 420 464 453 Adicionar Fábricas add-factory NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 469 420 610 453 Remover Fábricas remove-factory NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 512 373 650 406 Adicionar ozônio add-ozone NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 665 373 797 406 Remover ozônio remove-ozone NIL 1 T OBSERVER NIL NIL NIL NIL 1 MONITOR 211 11 299 56 Qtd. Ozônio count ozones 17 1 11 BUTTON 615 419 735 452 Emissão casas add-house NIL 1 T OBSERVER NIL NIL NIL NIL 1 SLIDER 18 82 191 115 albedo albedo 0 1 0.2 0.05 1 NIL HORIZONTAL @#$#@#$#@ ## WHAT IS IT? This is a model of energy flow in the earth, particularly heat energy. It shows the earth as rose colored, and the surface of the planet is represented by a black strip. Above the strip there is a blue atmosphere and black space at the top. Clouds and carbon dioxide (CO2) molecules can be added to the atmosphere. The CO2 molecules represent greenhouse gases that block infrared light that is emitted by the earth. Clouds block incoming or outgoing sun rays, influencing the heating up or cooling down of the planet. ## HOW IT WORKS Yellow arrowheads stream downward representing sunlight energy. Some of the sunlight reflects off clouds and more can reflect off the earth's surface. If sunlight is absorbed by the earth, it turns into a red dot, representing heat energy. Each dot represents the energy of one yellow sunlight arrowhead. The red dots randomly move around the earth, and its temperature is related to the total number of red dots. Sometimes the red dots transform themselves into infrared (IR) light that heads toward space, carrying off energy. The probability of a red dot becoming IR light depends on the earth's temperature. When the earth is cold, few red dots generate IR light; when it is hot, most do. The IR energy is represented by a magenta arrowhead. Each carries the same energy as a yellow arrowhead and as a red dot. The IR light goes through clouds but can bounce off CO2 molecules. There is a relation between the number of red dots in the earth and the temperature of the earth. This is because the earth temperature goes up as the total thermal energy is increased. Thermal energy is added by sunlight that reaches the earth as well as from infrared (IR) light reflected down to the earth. Thermal energy is removed by IR emitted by the earth. The balance of these determines the energy in the earth, which is proportional to its temperature. There are, of course, many simplifications in this model. The earth is not a single temperature, does not have a single albedo, and does not have a single heat capacity. Visible light is somewhat absorbed by CO2 and some IR light does bounce off clouds. No model is completely accurate. What is important is that a model reacts in some ways like the system it is supposed to model. This model does that, showing how the greenhouse effect is caused by CO2 and other gases that absorb IR. ## HOW TO USE IT The SUN-BRIGHTNESS slider controls how much sun energy enters the earth's atmosphere. A value of 1.0 corresponds to our sun. Higher values allow you to see what would happen if the earth was closer to the sun, or if the sun got brighter. The ALBEDO slider controls how much of the sun energy hitting the earth is absorbed. If the albedo is 1.0, the earth reflects all sunlight. This could happen if the earth froze, and it is indicated by a white surface. If the albedo is zero, the earth absorbs all sunlight. This is indicated as a black surface. The earth's albedo is about 0.6. You can add and remove clouds with buttons. Clouds block sunlight but not IR. You can add and remove greenhouse gases, represented as CO2 molecules. CO2 blocks IR light but not sunlight. The buttons add and subtract molecules in groups of 25 up to 150. The temperature of the earth is related to the amount of heat in the earth. The more red dots you see, the hotter it is. ## THINGS TO NOTICE Watch a single sunlight arrowhead. This is easier if you slow down the model using the slider at the top of the model. You can also use the WATCH A RAY button. What happens to the arrowhead when it hits the earth? Describe its later path. Does it escape the earth? What happens then? Do all arrowheads follow similar paths? ## THINGS TO TRY 1. Play with the model. Change the albedo and run the model. Add clouds and CO2 to the model and then watch a single sunlight arrowhead. What is the highest earth temperature you can produce? 2. Run the model with a bright sun but no clouds and no CO2. What happens to the temperature? It should rise quickly and then settle down around 37 degrees. Why does it stop rising? Why does the temperature continue to bounce around? Remember, the temperature reflects the number of red dots in the earth. When the temperature is constant, there are about as many incoming yellow arrowheads as outgoing IR ones. Why? 3. Explore the effect of albedo holding everything else constant. Does increasing the albedo increase or decrease the earth temperature? When you experiment, be sure to run the model long enough for the temperature to settle down. 4. Explore the effect of clouds holding everything else constant. 5. Explore the effect of adding 100 CO2 molecules. What is the cause of the change you observe? Follow one sunlight arrowhead now. ## EXTENDING THE MODEL Try to add some other factors influencing the earth's temperature. For example, you could add patches of vegetation and then see what happens as they are consumed for human occupation. Also, you could try to add variable albedo to the model, instead of having one value for the whole planet. You could have glaciers with high albedo, and seas with low albedo, and then evaluate what happens when the glaciers melt into the seas. ## NETLOGO FEATURES Note that clouds are actually made up of lots of small circular turtles. ## RELATED MODELS Daisyworld ## CREDITS AND REFERENCES This model is based on an earlier version created in 2005 by Robert Tinker for the TELS project. ## HOW TO CITE If you mention this model or the NetLogo software in a publication, we ask that you include the citations below. For the model itself: * Tinker, R. and Wilensky, U. (2007). NetLogo Climate Change model. http://ccl.northwestern.edu/netlogo/models/ClimateChange. Center for Connected Learning and Computer-Based Modeling, Northwestern University, Evanston, IL. Please cite the NetLogo software as: * Wilensky, U. (1999). NetLogo. http://ccl.northwestern.edu/netlogo/. Center for Connected Learning and Computer-Based Modeling, Northwestern University, Evanston, IL. ## COPYRIGHT AND LICENSE Copyright 2007 Uri Wilensky. ![CC BY-NC-SA 3.0](http://ccl.northwestern.edu/images/creativecommons/byncsa.png) This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License. To view a copy of this license, visit https://creativecommons.org/licenses/by-nc-sa/3.0/ or send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA. Commercial licenses are also available. To inquire about commercial licenses, please contact Uri Wilensky at uri@northwestern.edu. @#$#@#$#@ default true 0 Polygon -7500403 true true 150 5 40 250 150 205 260 250 airplane true 0 Polygon -7500403 true true 150 0 135 15 120 60 120 105 15 165 15 195 120 180 135 240 105 270 120 285 150 270 180 285 210 270 165 240 180 180 285 195 285 165 180 105 180 60 165 15 arrow true 0 Polygon -7500403 true true 150 0 0 150 105 150 105 293 195 293 195 150 300 150 box false 0 Polygon -7500403 true true 150 285 285 225 285 75 150 135 Polygon -7500403 true true 150 135 15 75 150 15 285 75 Polygon -7500403 true true 15 75 15 225 150 285 150 135 Line -16777216 false 150 285 150 135 Line -16777216 false 150 135 15 75 Line -16777216 false 150 135 285 75 bug true 0 Circle -7500403 true true 96 182 108 Circle -7500403 true true 110 127 80 Circle -7500403 true true 110 75 80 Line -7500403 true 150 100 80 30 Line -7500403 true 150 100 220 30 butterfly true 0 Polygon -7500403 true true 150 165 209 199 225 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