Carbon, Nitrogen and Water Cycle

In the carbon, nitrogen and water cycle component, IMAGE 2.4 includes models for describing the global carbon cycle (Terrestrial Carbon Model) and the global nitrogen and phosphate cycle.

Terrestrial Carbon Model	Global Nitrogen and Phosphate Cycle
Model documentation, input and output	Introduction
Model description	Point sources
Land-cover conversions	Nonpoint sources, denitrification and leaching
	Nonpoint sources, transport and retention in groundwater and surface water

Terrestrial Carbon Model, documentation, input and output

The Terrestrial Carbon Model

The Terrestrial Carbon Model (TCM) simulates the carbon (C) flux between the atmosphere and biosphere as altered by atmospheric CO₂concentrations, climate change and different land-cover conversions. The spatial resolution of the calculations is 0.5 degree latitude by 0.5 degree longitude.

Model documentation

Previous versions of the model are described in detail by Klein Goldewijk et al.(1995) and Alcamo et al. (1998). The basic structure of the terrestrial carbon model in IMAGE version 2.4 has not changed in comparison to IMAGE 2.2.
Comparison with recent studies, which still show a very broad range in CO₂fertilization factors, have shown that C-sequestration in IMAGE 2.2 is on the high end of the spectrum (see van Minnen, 2007). Therefore, we have decreased the CO₂fertilization factor by 50%.

Model input and output
Model input	Historical and updated land-cover map (LCM) Potential vegetation (NVM) CO₂concentration (ACM) Temperature map (GPS) Moisture availability (NVM)
Assumptions	Soil fertility and altitude
Model output	Net Primary Production (NPP) and Soil respiration fluxes Net Ecosystem Productivity (NEP) and Land-use emissions of CO₂

Carbon, Nitrogen and Water Cycle

Terrestrial Carbon Model, documentation, input and output

The Terrestrial Carbon Model

Model documentation

Model input and output

related dossiers

related theme sites

Key publication