Autumn warming reduces carbon uptake
29 Jan 2008 by Evoluted New Media
Research has suggested that, in terms of carbon, we lose more than we gain from warmer autumns.
Research has suggested that, in terms of carbon, we lose more than we gain from warmer autumns.
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| Warmer autumns may mean increased soil decomposisiton |
In northern ecosystems the autumn temperature has increased by 1.1ËšC whereas the spring temperature has increased by 0.8ËšC over the past twenty years. This imbalance is reducing the ability for the earth to remove carbon dioxide from the atmosphere.
Dr Shilong Piao, lead author of the study, said: "If warming in autumn occurs at a faster rate than in spring, the ability of northern ecosystems to sequester carbon will diminish in the future."
The international group used a model which incorporated measurements from the forest canopy and remote satellites. The results showed that although warming in the spring enhances carbon uptake as accelerated growth dominates over soil decomposition, in the autumn, warming increases soil decomposition to an extent that greatly decreases carbon uptake. The autumn warming effect is particularly prominent in the northern hemisphere where ecosystems lose carbon dioxide, offsetting 90% of the increased carbon uptake from the spring.
The international study was supported by European Community-funded projects, ENSEMBLES and CARBONEUROPE IP, the National Natural Science Foundation of China and Fluxnet-Canada. The findings are published this month in Nature.
By Leila Sattary
