Assessment of model estimates of land-atmosphere CO 2 exchange across Northern Eurasia
[Notes_IRSTEA]European Union 7th Framework Programme under project Page21 (grant 282700) [Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU International audience A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobiliz...
Published in: | Biogeosciences |
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Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , |
Other Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2015
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Subjects: | |
Online Access: | https://insu.hal.science/insu-01218089 https://insu.hal.science/insu-01218089/document https://insu.hal.science/insu-01218089/file/BIOGEOSCIENCES-Assessment%20of%20model%20estimates%20of%20land-atmosphere%20CO2%20exchange%20across%20Northern%20Eurasia.pdf https://doi.org/10.5194/bg-12-4385-2015 |
Summary: | [Notes_IRSTEA]European Union 7th Framework Programme under project Page21 (grant 282700) [Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU International audience A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO 2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960–2009 at 0.5 • resolution, which is a scale common among many global carbon and climate model simulations. Model performance benchmarks were drawn from comparisons against both observed CO 2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. Published by Copernicus Publications on behalf of the European Geosciences Union. 4386 M. A. Rawlins et al.: CO 2 Exchange Across Northern Eurasia The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m −2 yr −2 , equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960–1969 vs. 2000–2009), with a weakening CO 2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the ... |
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