Quantifying the impact of wintertime changes on the arctic carbon cycle
Abstract
The Arctic is the fastest warming region of the world, which has a strong impact on the carbon cycle and vegetation dynamics. Even though the largest changes in temperature are projected to occur in the winter, cold season processes are often understudied and underrepresented in carbon cycle studies. This study aims to evaluate and quantify the impact of wintertime changes on the arctic carbon cycle by improving the representation of wintertime processes in the LPJ-GUESS DGVM. Firstly, we addressed shortcomings in the simulation of the insulation capacity of snow and its influence on soil temperatures. We implemented a new multi-layer snow scheme to account for the influence of snow dynamics on soil thermodynamics and biogeochemistry. The new scheme improved the models ability to simulate soil temperature and permafrost dynamics. This resulted in significant changes to the modelled biogeochemistry such as increased winter respiration, changes in soil carbon content but also vegetation distribution. Looking forward, we will improve the physical controls on non-growing season greenhouse gas emissions in the model to enable a more realistic outgassing when soils freeze at the onset of winter. So far, our project demonstrates that wintertime changes significantly influence biogeochemical processes at high latitudes. By further refining modelled cold-season processes we aim to simulate snow-soil-vegetation interactions with improved certainty and provide more reliable future projections on the role of the cold season on the Arctic carbon cycle. Understanding these processes is essential to study the future of the arctic carbon cycle and associated climate feedbacks.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.U15A..08P