| 摘 要： |
Tropical vegetation respiration (TVR) is affected by extreme climate change. As it is very difficult to directly observe TVR, our understanding of the land-ocean-atmosphere carbon cycle, and particularly the regulatory effect of El Nino-Southern Oscillation (ENSO) on TVR and the land-atmosphere carbon balance, is very limited. Therefore, using Moderate Resolution Imaging Spectroradiometer (MODIS) products and meteorological data, we investigated the response of TVR to changes in ENSO during 2000-2015. The influence of El Nino on TVR was approximately 10.8% higher than that of La Nina. During El Nino years, a significant and anomalous increase in thermal measures related to TVR and ENSO and a significant and anomalous decrease in related hydrological measures favor the formation of warmer and drier climate conditions. Furthermore, the zonal distributions of air temperature and vertical velocity at 200-1000 hPa during El Nino years show that a stronger atmospheric inversion over tropical regions causes an increase in the surface temperature. Moreover, anomalous atmospheric subsidence inhibits the upward transport of water vapor, leading to a decrease in the cloud formation probability and reduced precipitation. In summary, increased surface temperatures caused by increased solar radiation and enhanced atmospheric inversion and decreased precipitation cause warmer and drier climate conditions, which forces TVR to increase. As TVR constitutes the key node of the land-atmosphere-carbon cycle process, we focus on TVR and its close linkage with ENSO events and further establish a knowledge framework for understanding the land-atmosphere-ocean carbon cycle. This study deepens our understanding of not only the mechanism of the land-atmosphere carbon balance but also the ocean-induced terrestrial ecosystem processes spurred by ENSO-involved climate change. (C) 2021 Elsevier B.V. All rights reserved. |
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