Increased terrestrial ecosystem respiration in China estimated by land-atmosphere coupling model

Ecosystem respiration (Re), the sum of heterotrophic respiration and autotrophic respiration, is an important component of the carbon cycle in terrestrial ecosystems, so accurate assessment of ecosystem respiration could help us to understand the mechanisms underlying the interaction between global carbon cycle and climate change. However, the ability of the Weather Research and Forecasting model coupled with the Noah land surface model with multiple-physics options (WRF/Noah-MP) to simulate Re had not yet been evaluated in China. In this study, the WRF/Noah-MP model is used to simulate the respiration of terrestrial ecosystems from 2002 to 2022 with spatial resolution of 12 km x 12 km in China. Results suggested that the R-2 of the Re simulated by WRF/ Noah-MP was 0.58, which indicated that the WRF/Noah-MP model had good ability to simulate ecosystem respiration. During 2002 similar to 2022, the annual average Re was about 5.56 Pg C yr(-1), with an increasing trend of 0.03 Pg C yr(-1). There were significant spatial and seasonal differences in China's Re. The average Re in summer accounted for about 50 % of the mean annual Re. As a consequence, the interaction between climate warming and terrestrial ecosystem respiration needs to receive more attention in the future.