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Abstract It has been widely reported that isoprene emissions from the Arctic ecosystem have a strong temperature response. Here we identify sedges (Carexspp. andEriophorumspp.) as key contributors to this high sensitivity using plant chamber experiments. We observe that sedges exhibit a markedly stronger temperature response compared to that of other isoprene emitters and predictions by the widely accepted isoprene emission model, the Model of Emissions of Gases and Aerosols from Nature (MEGAN). MEGAN is able to reproduce eddy-covariance flux observations at three high-latitude sites by integrating our findings. Furthermore, the omission of the strong temperature responses of Arctic isoprene emitters causes a 20% underestimation of isoprene emissions for the high-latitude regions of the Northern Hemisphere during 2000-2009 in the Community Land Model with the MEGAN scheme. We also find that the existing model had underestimated the long-term trend of isoprene emissions from 1960 to 2009 by 55% for the high-latitude regions.
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NSF BEAR-oNS Data: Leaf-Chamber Experiments for Investigating the Temperature Sensitivity of Arctic Isoprene Emitters near Toolik Field Station, Alaska, USA (2022-2023)
It has been widely reported that isoprene emissions from Arctic ecosystems show a strong temperature response, and that Arctic warming is increasing ecosystem isoprene emissions. We conducted leaf-chamber experiments on two major groups of Arctic isoprene emitters—sedges and willows—near Toolik Field Station, Alaska, USA. We identify sedges (Carex spp. and Eriophorum spp.) as key contributors to this high temperature sensitivity. Sedges exhibit a markedly stronger temperature response than other isoprene emitters and than predicted by widely used isoprene emission models. In addition, we find that the hourly temperature response curve of Salix spp., the dominant isoprene-emitting shrub in the Arctic, is similar to that of temperate plants. In contrast, willow isoprene emission capacity or emission factor shows a more substantial-than-expected response to the previous day’s mean ambient temperature.
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- Award ID(s):
- 2041251
- PAR ID:
- 10670375
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- ISOPRENE
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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