Siberian 2020 heatwave increased spring CO2uptake but not annual CO2uptake - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue Environmental Research Letters Année : 2021

Siberian 2020 heatwave increased spring CO2uptake but not annual CO2uptake

Résumé

Siberia experienced an unprecedented strong and persistent heatwave in winter to spring of 2020. Using bottom-up and top-down approaches, we evaluated seasonal and annual CO2 fluxes of 2020 in the northern hemisphere (north of 30 °N), focusing on Siberia where the pronounced heatwave occurred. We found that, over Siberia, CO2 respiration loss in response to the pronounced positive winter temperature anomaly was greater than in previous years. However, continued warming in the spring enhanced photosynthetic CO2 uptake, resulting in the largest seasonal transition in net ecosystem CO2 exchange; that is, the largest magnitude of the switch from the net CO2 loss in winter to net CO2 uptake in spring until June. However, this exceptional transition was followed by the largest reduction in CO2 uptake in late summer due to multiple environmental constraints, including a soil moisture deficit. Despite a substantial increase of CO2 uptake by 22 ± 9 gC m-2 in the spring in response to the heatwave, the mean annual CO2 uptake over Siberia was slightly lower (3 ± 13 gC m-2yr-1) than the average of the previous five years. These results highlight the highly dynamic response of seasonal carbon fluxes to extreme temperature anomalies at high latitudes, indicating a seasonal compensation between abnormal uptake and release of CO2 in response to extreme warmth that may limit carbon sink capacity in high northern latitudes.
Fichier principal
Vignette du fichier
Kwon_2021_Environ._Res._Lett._16_124030.pdf (1.83 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-03487740 , version 1 (19-12-2021)

Licence

Paternité

Identifiants

Citer

Min-Jung Kwon, Ashley P. Ballantyne, Philippe Ciais, Ana Bastos, Frédéric Chevallier, et al.. Siberian 2020 heatwave increased spring CO2uptake but not annual CO2uptake. Environmental Research Letters, 2021, 16 (12), pp.124030. ⟨10.1088/1748-9326/ac358b⟩. ⟨hal-03487740⟩
50 Consultations
28 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More