Nathalie de Noblet-Ducoudré

Abstract: This work presents a new dynamic global vegetation model designed as an extension of an existing surface-vegetation-atmosphere transfer scheme which is included in a coupled ocean-atmosphere general circulation model. The new dynamic global vegetation model simulates the principal processes of the continental biosphere influencing the global carbon cycle (photosynthesis, autotrophic and heterotrophic respiration of plants and in soils, fire, etc.) as well as latent, sensible, and kinetic energy exchanges at the surface of soils and plants. As a dynamic vegetation model, it explicitly represents competitive processes such as light competition, sapling establishment, etc. It can thus be used in simulations for the study of feedbacks between transient climate and vegetation cover changes, but it can also be used with a prescribed vegetation distribution. The whole seasonal phenological cycle is prognostically calculated without any prescribed dates or use of satellite data. The model is coupled to the IPSL-CM4 coupled atmosphere-ocean-vegetation model. Carbon and surface energy fluxes from the coupled hydrology-vegetation model compare well with observations at FluxNet sites. Simulated vegetation distribution and leaf density in a global simulation are evaluated against observations, and carbon stocks and fluxes are compared to available estimates, with satisfying results.

TL;DR: It is shown that land-use change plays an additional important role in controlling regional runoff values, particularly in the tropics, and its contribution is substantially larger than that of climate change.

TL;DR: In this article, a fully coupled land-ocean-atmosphere GCM is used to explore the biogeophysical impact of large-scale deforestation on surface climate, and it is shown that the surface albedo increase owing to deforestation has a cooling effect of 21.36 K globally.

TL;DR: The Land Use Model Intercomparison Project (LUMIP) aims to further advance understanding of the impacts of land-use and land-cover change (LULCC) on climate, specifically addressing the following questions.

TL;DR: A robust alternative to prediction that is based on using integrated assessments within the framework of vulnerability studies is suggested and a number of research priorities and the establishment of education programs in Earth Systems Science are recommended.