Advancing greenup and snowmelt: Their implications on the carbon cycle of Alaskan tundra ecosystems
Abstract
The high latitude regions have experienced disproportionate changes in temperature and precipitation, which may alter the latitudinal gradients in the greenup and snowmelt timings and associated vegetation growth and carbon dynamics of tundra ecosystems. We analyzed remotely-sensed and ground-based datasets and implemented a process-based model (the Ecosystem Demography model version 2, ED2) at seven tundra flux tower sites in Alaska during 20012018. We found that the rates of advance of greenup timing have been largely driven by the increasing rates of spring temperature, which shows latitudinal gradients over the study sites, while the snowmelt timing did not show such trends. We also noticed that that ecosystem response to early greenup or delayed snowmelt is largely determined by the local climatic constraints. At the higher latitude sites that are strongly colimited by temperature and water, increases in the net ecosystem productivity (NEP) due to warming-driven early greenup were amplified. At the lower latitude site that is only weakly limited by water, we found that the NEP decreases by caused delayed snowmelt were alleviated due to a relief of water stress. Our results highlight the importance of understanding the role of snowmelt timing on the phenology of the Arctic tundra ecosystem, as well as its impact on vegetation growth and carbon dynamics under different climatic limits, under ongoing climate change. This study was funded by the Korea Polar Research Institute (KOPRI, PE17900 and PE18900) and the National Research Foundation of Korea (NRF) Grant from the Korean government (MSIT; the Ministry of Science and ICT) (2020R1C1C101488612).
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.B22D..05K