Journal Article
Geoscientific Model Development, vol. 12, iss. 5, pp. 1753-1764, 2019
Authors
Min Chen, Chris R. Vernon, Maoyi Huang, Katherine V. Calvin, Ian P. Kraucunas
Abstract
Abstract. Demeter is a community spatial downscaling model that
disaggregates land use and land cover changes projected by integrated
human–Earth system models. Demeter has not been intensively calibrated, and
we still lack good knowledge about its sensitivity to key parameters and
parameter uncertainties. We used long-term global satellite-based land
cover records to calibrate key Demeter parameters. The results identified the
optimal parameter values and showed that the parameterization substantially
improved the model's performance. The parameters of intensification ratio and
selection threshold were the most sensitive and needed to be carefully tuned,
especially for regional applications. Further, small parameter uncertainties
after calibration can be inflated when propagated into future scenarios,
suggesting that users should consider the parameterization equifinality to
better account for the uncertainties in Demeter-downscaled products. Our
study provides a key reference for Demeter users and ultimately contributes
to reducing the uncertainties in Earth system model simulations.
