English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The commonly adopted biogeochemistry spin-up process in an Earth system model(ESM) is to run the model for hundreds to thousands of years subject toperiodic atmospheric forcing to reach dynamic steady state of thecarbon–nitrogen (CN) models. A variety of approaches have been proposed toreduce the computation time of the spin-up process. Significant improvementin computational efficiency has been made recently. However, a longsimulation time is still required to reach the common convergence criteria ofthe coupled carbon–nitrogen model. A gradient projection method was proposedand used to further reduce the computation time after examining the trend ofthe dominant carbon pools. The Community Land Model version 4 (CLM4) with acarbon and nitrogen component was used in this study. From point-scalesimulations, we found that the method can reduce the computation time by20–69% compared to one of the fastest approaches in the literature. Wealso found that the cyclic stability of total carbon for some cases differsfrom that of the periodic atmospheric forcing, and some cases even showedinstability. Close examination showed that one case has a carbon periodicitymuch longer than that of the atmospheric forcing due to the annual firedisturbance that is longer than half a year. The rest was caused by theinstability of water table calculation in the hydrology model of CLM4. Theinstability issue is resolved after we replaced the hydrology scheme in CLM4with a flow model for variably saturated porous media

Accelerating the spin-up of the coupled carbon and nitrogen cycle model in CLM4