1st Brazilian Symposium on Global Enviromental Change, Rio de Janeiro, March 2007 Modelling Land Change: The Scientific Challenges Gilberto Câmara Director National Institute for Space Research Brazil What is a Model? Model = a simplified description of a complex entity or process Deforestation deforest Farmer E0 • income owns E4 space • land use • soil type Model = entities + relations + attributes + rules source: Carneiro (2006) Modelling Complex Problems Application of multidisciplinary knowledge to produce a model. If (... ? ) then ... Desforestation? What is Computational Modelling? Design and implementation of computational enviroments for modelling Requires a formal and stable description Implementation allow experimentation Rôle of computer representation Bring together expertise in different field Make the different conceptions explicit Make sure these conceptions are represented in the information system Scientific Challenges “Third culture” Modelling of physical phenomena Understanding of human dimensions How to model human actions? What makes people do certain things? Why do people compete or cooperate? What are the causative factors of human actions? Uncertainty on basic equations Limits for Models Social and Economic Systems Quantum Gravity Particle Physics Living Systems Global Change Chemical Reactions Hydrological Models Solar System Dynamics Meteorology Complexity of the phenomenon source: John Barrow (after David Ruelle) Public Policy Issues What are the acceptable limits to land cover change activities in the tropical regions in the Americas? What are the future scenarios of land use? How can food production be made more efficient and productive? How can our biodiversity be known and the benefits arising from its use be shared fairly? How can we manage our water resources to sustain our expected growth in urban population? Modelling Land Change in Amazonia Territory (Geography) Money (Economy) Modelling (GIScience) Culture (Antropology) Dynamic Spatial Models Forecast tp - 20 tp - 10 tp Calibration source: Cláudia Almeida Calibration tp + 10 Challenge: How do people use space? Soybeans Loggers Competition for Space Small-scale Farming Source: Dan Nepstad (Woods Hole) Ranchers Dynamic areas (current and future) Escada et al. (2005) New Frontiers INPE 2003/2004: Intense Pressure Future expansion Deforestation Forest Non-forest Clouds/no data Altamira (Pará) – LANDSAT Image – 22 August 2003 Altamira (Pará) – MODIS Image – 07 May 2004 Imagem Modis de 2004-05-21, com excesso de nuvens Altamira (Pará) – MODIS Image – 21 May 2004 Altamira (Pará) – MODIS Image – 07 June 2004 Altamira (Pará) – MODIS Image – 22 June 2004 6.000 hectares deforested in one month! Altamira (Pará) – LANDSAT Image – 07 July 2004 Amazonian new frontier hypothesis (Becker) “The actual frontiers are different from the 60’s and the 70’s In the past it was induced by Brazilian government to expand regional economy and population, aiming to integrate Amazônia with the whole country. Today, induced mostly by private economic interests and concentrated on focus areas in different regions. Modelling Human Actions: Two Approaches Models based on global factors Explanation based on causal models “For everything, there is a cause” Human_actions = f (factors,....) Emergent models Local actions lead to global patterns Simple interactions between individuals lead to complex behaviour “More is different” “The organism is intelligent, its parts are simpleminded” Emergence: Clocks, Clouds or Ants? Clocks Paradigms: Newton’s laws (mechanistic, cause-effect phenomena describe the world) Clouds Stochastic models Theory of chaotic systems Ants The colony behaves intelligently Intelligence is an emergent property Statistics: Humans as clouds y=a0 + a1x1 + a2x2 + ... +aixi +E Establishes statistical relationship with variables that are related to the phenomena under study Basic hypothesis: stationary processes Exemples: CLUE Model (University of Wageningen) Statistics: Humans as clouds MODEL 7: Variables source: Aguiar (2006) R² = .86 PORC3_AR Description Percentage of large farms, in terms of area LOG_DENS Population density (log 10) PRECIPIT stb p-level 0,27 0,00 0,38 0,00 -0,32 0,00 LOG_NR1 Avarege precipitation Percentage of small farms, in terms of number (log 10) 0,29 0,00 DIST_EST Distance to roads -0,10 0,00 LOG2_FER Percentage of medium fertility soil (log 10) -0,06 0,01 PORC1_UC Percantage of Indigenous land -0,06 0,01 Statistical analysis of deforestation Área de estudo – ALAP BR 319 e entorno (Aguiar, 2006b) ALAP BR 319 Estradas pavimentadas em 2010 Estradas não pavimentadas Rios principais Portos BASELINE SCENARIO – Hot spots of change (1997 a 2020) % mudança 1997 a 2020: ALAP BR 319 Estradas pavimentadas em 2010 Estradas não pavimentadas Rios principais source: Aguiar (2006b) 0.0 – 0.1 0.1 – 0.2 0.2 – 0.3 0.3 – 0.4 0.4 – 0.5 0.5 – 0.6 0.6 – 0.7 0.7 – 0.8 0.8 – 0.9 0.9 – 1.0 GOVERNANCE SCENARIO – Differences from baseline scenario (Aguiar, 2006b) ALAP BR 319 Estradas pavimentadas em 2010 Estradas não pavimentadas Rios principais Protection areas Sustainable areas Differences: Less: More: 0.0 -0.50 0.0 0.10 The trouble with statistics Extrapolation of current measured trends How do we know if tommorow will be like today? How do we incorporate feedbacks? Complex adaptative systems How come that a city with many inhabitants functions and exhibits patterns of regularity? How come that an ecosystem with all its diverse species functions and exhibits patterns of regularity? How can we explain how similar exploration patterns appear on the Amazon rain forest? Results of human society such as economies Source: John Finnigan (CSIRO) Agents and CA: Humans as ants Identify different actors and try to model their actions Farms Settlements 10 to 20 anos Recent Settlements (less than 4 years) Escada, 2003 Old Settlements (more than 20 years) Different agents, different motivations Intensive agriculture (soybeans) export-based responsive to commodity prices, productivity and transportation logistics Extensive cattle-ranching local + export responsive to land prices, sanitary controls and commodity prices photo source: Edson Sano (EMBRAPA) Large-Scale Agriculture Agricultural Areas (ha) 1970 Legal Amazonia Brazil 1995/1996 % 5,375,165 32,932,158 513 33,038,027 99,485,580 203 Source: IBGE - Agrarian Census Different agents, different motivations Small-scale settlers Associated to social movements (MST, Church) Responsive to capital availability, land ownership, and land productivity Can small-scale economy be sustainable? Wood loggers Primarily local market Responsive to prime wood availability, official permits, transportation logistics Land speculators Appropriation of public lands Responsive to land registry controls, law enforcement Agent model using Cellular Automata 1985 Small farms environments: 500 m resolution Categorical variable: deforested or forest One neighborhood relation: •connection through roads Large farm environments: 2500 m resolution 1997 Continuous variable: % deforested Two alternative neighborhood relations: •connection through roads • farm limits proximity 1997 The trouble with agents Many agent models focus on proximate causes directly linked to land use changes (in the case of deforestation, soil type, distance to roads, for instance) What about the underlying driving forces? Remote in space and time Operate at higher hierarchical levels Macro-economic changes and policy changes Game theory and mobility Two players get in a strive can choose shoot or not shoot their firearms. If none of them shoots, nothing happens. If only one shoots, the other player runs away, and then the winner receives $1. If both decide to shoot, each group pays $10 due to medical cares. B shoots B does not shoot A shoots (-10,-10) (+1,-1) A does not shoot (-1,+1) (0,0) Game theory and mobility Three strategies A - ((10%;; $200; 0) B - ((50%;; $200; 0) C - ((100%;; $200;; 0)) Game theory and mobility What happens when players can move? If a player loses too much, he might move to an adjacent cell Mobility breaks the Nash equilibrium! TerraME Runtime Environment TerraME INTERPRETER • model syntax semantic checking • model execution TerraView • data acquisition • data visualization • data management • data analysis LUA interpreter TerraME framework data model model TerraME/LUA interface MODEL DATA Model source code TerraLib database data Eclipse & LUA plugin • model description • model highlight syntax Flexible neighbourhoods Consolidated area Emergent area Scale Scale is a generic concept that includes the spatial, temporal, or analytical dimensions used to measure any phenomenon. Extent refers to the magnitude of measurement. Resolution refers to the granularity used in the measures. (Gibson et al. 2000) Multi-scale approach The trouble with current theories of scale Conservation of “energy”: national demand is allocated at local level No feedbacks are possible: people are guided from the above The search for a new theory of scale Non-conservative: feedbacks are possible Linking climate change and land change Future of cities and landscape integrate to the earth system The big challenge: a theory of scale Nested Cellular Automata U U U Environments can be nested Multiscale modelling Space can be modelled in different resolutions Computational Modelling with Cell Spaces Cell Spaces fonte: Carneiro (2006) Components Cell Spaces Generalizes Proximity Matriz – GPM Hybrid Automata model Nested enviroment Cell Spaces Cellular Data Base Resolution 2500 m 2.500 m e 500 m TerraME functionality TerraME INTERPRETER • model syntax semantic checking • model execution TerraView • data acquisition • data visualization • data management • data analysis LUA interpreter TerraME framework data model model TerraME/LUA interface MODEL DATA Model source code fonte: Carneiro (2006) TerraLib database data Eclipse & LUA plugin • model description • model highlight syntax Global Land Project • What are the drivers and dynamics of variability and change in terrestrial humanenvironment systems? • How is the provision of environmental goods and services affected by changes in terrestrial humanenvironment systems? • What are the characteristics and dynamics of vulnerability in terrestrial humanenvironment systems? References Carneiro, T., 2006. Nested-CA: a foundation for multiscale modeling of land use and land change., in PhD Thesis in Computer Science. INPE: São José dos Campos, Brazil. Aguiar, A., 2006a. Modeling Land Use Change in the Brazilian Amazon: Exploring Intra-Regional Heterogeneity, in PhD Thesis, Remote Sensing Program, INPE: Sao Jose dos Campos Escada, M.I.S., 2003. Evolução de Padrões da Terra na Região Centro-Norte de Rondônia. 2003, INPE: São José dos Campos. p. 164. Escada, M.I.S., et al.,2005. Padrões e Processos de Ocupação nas Novas Fronteiras da Amazônia: O Interflúvio do Xingu/Iriri Estudos Avançados, 19(54): p. 9-23.