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Abstract Earth system models (ESMs) have been rapidly developed in recent decades to advance our understanding of climate change‐carbon cycle feedback. However, those models are massive in coding, require expensive computational resources, and have difficulty in diagnosing their performance. It is highly desirable to develop ESMs with modularity and effective diagnostics. Toward these goals, we implemented a matrix approach to the Community Land Model version 5 (CLM5) to represent carbon and nitrogen cycles. Specifically, we reorganized 18 balance equations each for carbon and nitrogen cycles among the 18 vegetation pools in the original CLM5 into two matrix equations. Similarly, 140 balance equations each for carbon and nitrogen cycles among the 140 soil pools were reorganized into two additional matrix equations. The vegetation carbon and nitrogen matrix equations are connected to soil matrix equations via litterfall. The matrix equations fully reproduce simulations of carbon and nitrogen dynamics by the original model. The computational cost for forwarding simulation of the CLM5 matrix model was 26% more expensive than the original model, largely due to calculation of additional diagnostic variables, but the spin‐up computational cost was significantly saved. We showed a case study on modeled soil carbon storage under two forcing data sets to illustrate the diagnostic capability that the matrix approach uniquely offers to understand simulation results of global carbon and nitrogen dynamics. The successful implementation of the matrix approach to CLM5, one of the most complex land models, demonstrates that most, if not all, the biogeochemical models can be reorganized into the matrix form to gain high modularity, effective diagnostics, and accelerated spin‐up.
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CESM2-CLM5 Framework for Hindcasting Tropical Mountain Glaciation: Examples and Pre-Industrial Validation Analysis
This data archive contains data and code related to simulating tropical mountain glaciation within high-resolution standalone simulations by the Community Land Model version 5 (CLM5) with a data atmosphere created by the Community Earth System Model version 2. The information here is intended allow one to perform simulations of this type as well as evaluate the performance of the CESM2-CLM5 simulation framework for example tropical mountain glaciers under pre-industrial climate conditions. This work was funded by the Sedimentary Geology and Paleobiology program of the National Science Foundation (EAR-1849754).
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- Award ID(s):
- 1849754
- PAR ID:
- 10350662
- Publisher / Repository:
- Mendeley
- Date Published:
- Subject(s) / Keyword(s):
- Natural Sciences
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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