[A-CG35] Global Carbon Cycle Observation and Analysis

[ACG35-03] Impact of anomalous high temperature in the 2020 spring-summer season on the terrestrial carbon cycle in Russia

*Takuto Taguchi¹, Kazuhito Ichii¹, Yuhei Yamamoto¹, Dmitry Belikov¹, Prabir Patra², Naveen Chandra², Shunji Kotsuki¹, Kazuyoshi Suzuki², Tetsuya Hiyama³ (1.Center for Environmental Remote Sensing, Chiba University, 2.Japan Agency for Marine-Earth Science and Technology, 3.Institute for Space-Earth Environmental Research, Nagoya University)

Keywords:Terrestrial carbon cycle, Remote sensing of Vegetation, Anomalous high temperature

The seasonal variations in the terrestrial carbon cycle across northern high-latitude zones are tightly associated with the timing and duration of the temperature variations. In the spring to summer of 2020, large parts of Russia experienced unprecedented hot weather, recording nearly +6°C; however, its long-lasting heatwave effects on the net ecosystem carbon balance remain unclear. Here, we analyzed Russia’s vegetation phenology in 2020 with Moderate Resolution Imaging Spectroradiometer (MODIS) sensor measurements and seasonal terrestrial carbon cycle variations using two-different approaches (Top-down and Bottom-up) CO₂ flux estimations. MODIS Land surface temperature (LST) represents extreme positive temperature anomalies in western and central Russia in the first half of 2020, which neatly agrees with the early onset of spring compared to the past 20 years. Two estimations models show enhanced carbon uptake from April to June in the center region (-0.13 ± 0.04 [PgC] in 2001-2019 vs. -0.2 [PgC] in 2020 by Top-down; -0.12 ± 0.03 [PgC] in 2001-2019 vs. -0.24 [PgC] in 2020 by Bottom-up). Revealed by detailed analysis, year-round increased total ecosystem respiration across all regions can be found in response to warming enhancement; its yearly amplified emission offset carbon uptake during the first half of 2020. This may be critical in investigating the impact of future extreme climates on the terrestrial carbon cycle across northern high-latitude regions.