http://ecoinformatics.uvm.edu/projects/ ... model.html
(pas réussi à télécharger le power point)The Global Unified Metamodel of the Biosphere (GUMBO)
The Global Unified Metamodel of the Biosphere (GUMBO) is an exploration through simulation modeling into the global dynamics and interactions of the earth sociology, economy, and ecology. GUMBO, developed and maintained by Roelof Boumans, is aimed at assessing the dynamics of ecosystem services. Its overall resolution and complexity are adjusted to meet the conflicting criteria of:
- complex enough to include the production and interconnections among the major global ecosystem services, and
- simple enough to be distributed and run on a desktop PC by a broad range of users.
GUMBO is central to many activities at the Ecoinformatics Collaboratory that rely on the ability to generate and analyze global change scenarios whose definition includes economic and cultural dimensions. Among the project that use or depend on GUMBO are the Ecosystem Services Database and the ARIES framework.
GUMBO structure: a brief introduction
Some results of a scenario analysis done with GUMBO
Gumbo consists of five sectors or spheres: Atmosphere, Lithosphere, Hydrosphere, Biosphere, and Antrophosphere (human systems). It is also divided into 11 biomes or ecosystem types which encompass the entire surface area of the planet: Open Ocean, Coastal Ocean, Forests, Grasslands, Wetlands, Lakes/Rivers, Deserts, Tundra, Ice/rock, Croplands, and Urban. Global energy, carbon, nitrogen, and water dynamics are incorporated in Gumbo, along with soil erosion and formation, fossil fuel formation and use, plant and animal productivity and harvest, human population, energy, biomass, and water use, economic production and welfare, and changes in natural, built, human, and social capital.
Ecosystem services are aggregated to 10 major types in GUMBO based on flows and storages in the model. These are: Gas regulation, climate regulation, disturbance regulation, water use, soil formation, nutrient cycling, waste treatment, food production, raw materials, and recreation/cultural. These 10 services together represent the contribution of natural capital to the economic production process. They combine with renewable and nonrenewable fuels, built capital, human capital (labor and knowledge), and social capital to produce economic goods and services. They also contribute directly to human welfare. Several different methods to value ecosystem services are implemented in the model, allowing users to observe all of them and compare the results. Historical data on land use, CO2 concentration in the atmosphere, global mean temperature, economic production, population, and several other variables are used to calibrate the model.
GUMBO is available for download in our download page. You can also download a powerpoint presentation detailing its structure and applications.
D'après les prévisions de ce modèle, le crash vient inévitablement avant 2100, comme pour le rapport Meadows, et dans les cas les plus pessimistes, les courbes suggèreraient que nous serions déjà sur la pente descendante.
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