Regional trends in terrestrial carbon exchange and their seasonal signatures
Regional trends in terrestrial carbon exchange and their seasonal signatures
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DOI：
10.1111/j.1600-0889.2011.00534.x
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发表时间：
2011-01
期刊：
影响因子：
--
通讯作者：
K. Gurney;W. Eckels
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文献类型：
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作者：
K. Gurney;W. Eckels
陆地碳交换的趋势及其机制驱动因素是了解碳库如何应对气候变化的关键组成部分。在这里，我们利用大气 CO2 反演结果显示了 1980 年至 2008 年季节性非化石陆地-大气碳交换的趋势。分析了四个指标：生长季净通量（GSNF）、休眠季净通量（DSNF）、幅度和年净碳通量（NCF）。我们发现，全球陆地碳汇正在以 -0.057 ± 0.01 PgC yr-2 的速度增强，导致在研究期间额外吸收量为 -1.65 ± 0.29 PgC。总土地占用量的增加是由 DSNF (-0.04 ± 0.01 PgC yr-2) 下降和 GSNF (-0.02 ± 0.008 PgC yr-2) 强化驱动的。区域分析显示非洲大陆南半部发挥主导作用； GSNF 的强化（-0.02 ± 0.005 PgC yr-2）和 DSNF 的下降（-0.013 ± 0.004 PgC yr-2）意味着非洲已从 20 世纪 80 年代的净碳源转向接近中性排放。相比之下，北美温带 (0.015±0.007 PgC yr-2) 和热带美洲 (0.01 ± 0.005 PgC yr-2) GSNF 减弱。
The trends of terrestrial carbon exchange and their mechanistic drivers are key components in understanding how carbon reservoirs will respond to climate change. Here we show trends in seasonal non-fossil land-atmosphere carbon exchange from 1980 to 2008 using atmospheric CO2 inversion results. Four indices were analysed: growing-season net flux (GSNF), dormant-season net flux (DSNF), amplitude and annual net carbon flux (NCF). We find that the global land carbon sink is intensifying at -0.057 ± 0.01 PgC yr-2, resulting in -1.65 ± 0.29 PgC of additional uptake over the period examined. This increased total land uptake is driven by a decline in the DSNF (-0.04 ± 0.01 PgC yr-2) and intensification of the GSNF (-0.02 ± 0.008 PgC yr-2). Regional analysis shows the dominant role of the southern half of the African continent; intensification of the GSNF (-0.02 ± 0.005 PgC yr-2) and a decline in the DSNF (-0.013 ± 0.004 PgC yr-2) imply that Africa has shifted from a net carbon source in the 1980s to near-neutral emissions. By contrast, a weakening of the GSNF is found in temperate North America (0.015±0.007 PgC yr-2) and tropical America (0.01 ± 0.005 PgC yr-2).