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Afforestation in China cools local land surface temperature.

ABSTRACT: China has the largest afforested area in the world (?62 million hectares in 2008), and these forests are carbon sinks. The climatic effect of these new forests depends on how radiant and turbulent energy fluxes over these plantations modify surface temperature. For instance, a lower albedo may cause warming, which negates the climatic benefits of carbon sequestration. Here, we used satellite measurements of land surface temperature (LST) from planted forests and adjacent grasslands or croplands in China to understand how afforestation affects LST. Afforestation is found to decrease daytime LST by about 1.1 ± 0.5 °C (mean ± 1 SD) and to increase nighttime LST by about 0.2 ± 0.5 °C, on average. The observed daytime cooling is a result of increased evapotranspiration. The nighttime warming is found to increase with latitude and decrease with average rainfall. Afforestation in dry regions therefore leads to net warming, as daytime cooling is offset by nighttime warming. Thus, it is necessary to carefully consider where to plant trees to realize potential climatic benefits in future afforestation projects.

SUBMITTER: Peng SS

PROVIDER: S-EPMC3939881 | biostudies-other | 2014 Feb

REPOSITORIES: biostudies-other

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Afforestation in China cools local land surface temperature.

Peng Shu-Shi SS Piao Shilong S Zeng Zhenzhong Z Ciais Philippe P Zhou Liming L Li Laurent Z X LZ Myneni Ranga B RB Yin Yi Y Zeng Hui H

Proceedings of the National Academy of Sciences of the United States of America 20140210 8

China has the largest afforested area in the world (∼62 million hectares in 2008), and these forests are carbon sinks. The climatic effect of these new forests depends on how radiant and turbulent energy fluxes over these plantations modify surface temperature. For instance, a lower albedo may cause warming, which negates the climatic benefits of carbon sequestration. Here, we used satellite measurements of land surface temperature (LST) from planted forests and adjacent grasslands or croplands ...[more]

PMID: 24516135

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Afforestation in China cools local land surface temperature.

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Afforestation in China cools local land surface temperature.

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