A new dust cycle model with dynamic vegetation: LPJ-dust version 1.0 Bristol Research Initiative for the Dynamic Global Environment (BRIDGE), School of Geographical Sciences, University Road, University of Bristol, Bristol, BS8 1SS, UK
Received: 07 April 2010 – Published in Geosci. Model Dev. Discuss.: 23 April 2010 Abstract. This paper presents a new offline dust cycle model which uses the
Lund-Potsdam-Jena dynamic global vegetation model (Sitch et al., 2003) to
calculate time varying dust sources. Surface emissions are calculated by
simulating the processes of saltation and sandblasting using an existing
model (Tegen et al., 2002). Dust particles are transported using the TOMCAT
chemical transport model (Chipperfield, 2006). Dust particles are removed from the
atmosphere by dry deposition and sub-cloud scavenging. The model is designed
so that it can be driven using reanalysis data or GCM derived fields.
Revised: 20 December 2010 – Accepted: 20 January 2011 – Published: 16 February 2011
To improve the performance of the model, threshold values for vegetation
cover, soil moisture, snow depth and threshold friction velocity, used to
determine surface emissions are tuned. The effectiveness of three sub-cloud
scavenging schemes are also tested. An ensemble of tuning experiments are
evaluated against dust deposition and surface concentration measurements.
Surface emissions which produce the best agreement with observations range
from 1600 to 2400 Mtyr−1.
Citation: Shannon, S. and Lunt, D. J.: A new dust cycle model with dynamic vegetation: LPJ-dust version 1.0, Geosci. Model Dev., 4, 85-105, doi:10.5194/gmd-4-85-2011, 2011.