Bibliothèque Tour du Valat

Se connecter

Mot de passe oublié ?
Pas encore inscrit ?

La Tour du Valat

Institut de recherche pour la conservation des zones humides méditerranéennes

Détail

Ajouter au panier

Ajouter au panier

Lien vers la notice

Titre :	The climate of the Mediterranean Basin and of Eurasia of the last glacial maximum as reconstructed by inverse vegetation modelling and pollen data
Auteurs :	Joel Guiot, Auteur ; Franck Torre, Auteur ; Rachid Cheddadi, Auteur ; Odile Peyron, Auteur ; Pavel Tarasov, Auteur ; Dominique Jolly, Auteur ; Jed O. Kaplan, Auteur
Type de document :	Article
Dans :	Ecologia Mediterranea (25(2) 1999)
Article en page(s) :	193-204
Résumé :	Classical climate reconstruction based on statistical method implicitly assumes that the atmospheric CO2 concentration, which has greatly fluctuated during the Quaternary, has no influence on the vegetation. In order to attenuate this assumption, we propose to use a process-based vegetation model (BIOME 3.5) in inverse mode to reconstruct from pollen data the most probable climate under lowered CO2 concentration in the biosphere. Appropriate tools to match the model outputs with the pollen data are developed to generate a probability distribution associated with the reconstruction (Monte Carlo sampling and neural network techniques). The method is validated with modern pollen data from Europe and Northern Eurasia: it is able to reconstruction modern climate with a sometimes large error bar from pollen data. The error bar depends in fact on the tolerance of the vegetation to the corresponding climatic variable. The application to 71 pollen assemblages from these regions, representing the last glacial maximum (LGM: 18,000 14C-yr B.P.), is done through two experiments: modern and LGM CO2 concentration. We show that three is a good agreement between previous results based on statistical methods and inverse modelling in the northern part of the studied region. In the Mediterranean region and southern Siberia, the summer temperatures and the water availability parameters could be higher than previously reconstructed, because of the CO2 effect.

FAQ

Infos pratiques

Heures d'ouverture et contact

Lundi , mardi et jeudi de 9h à 12h et de 13h à 17h00 : ouverture au public ...

Liens utiles

A-
A
A+