Spin-up processes in the Community Land Model version 4 with explicit carbon and nitrogen components

摘要: a b s t r c Given arbitrary initial conditions, terrestrial biogeochemistry models typically require hundreds to thousands of years for carbon and nitrogen in various pools reach steady-state solutions. Such long spin-up processes not only pose significant burden computational resources, but also are against observational evidence. The objectives this study to: (1) compare four methods their solutions using the Community Land Model version 4 with explicit (CLM4CN2); (2) elucidate potential weaknesses model that responsible spin-ups. can be classified into two groups: spins up from conditions (e.g., traditional native dynamics or ND method); is initialized observed soil organic matter (SOM) pools. Our results show that: compared ND, accelerating SOM decom- position rates during reduces timescales tropical forests, grasslands, temperate boreal forests; some decelerating denitrification leaching decomposition saves more time than method accelerated; (3) reasonable initialization helps its steady state quickly. We find ecosystems vegetation seasonality described by changed inconsistent method. CLM4CN has improving simulations reducing if structure ways representing immobilization improved.