Simulating impacts on UK air quality from net-zero forest planting scenarios

Purser, Gemma ORCID: https://orcid.org/0000-0001-7062-6840; Heal, Mathew R.; Carnell, Edward J. ORCID: https://orcid.org/0000-0003-0870-1955; Bathgate, Stephen; Drewer, Julia ORCID: https://orcid.org/0000-0002-6263-6341; Morison, James I.L.; Vieno, Massimo ORCID: https://orcid.org/0000-0001-7741-9377. 2023 Simulating impacts on UK air quality from net-zero forest planting scenarios. Atmospheric Chemistry and Physics, 23 (21). 13713-13733. https://doi.org/10.5194/acp-23-13713-2023

Before downloading, please read NORA policies.

Preview

Text N535407JA.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (5MB) | Preview

Abstract/Summary

The UK proposes additional bioenergy plantations and afforestation as part of measures to meet net-zero greenhouse gas emissions, but species and locations are not yet decided. Different tree species emit varying amounts of isoprene and monoterpene volatile organic compounds that are precursors to ozone and secondary organic aerosol (SOA) formation, the latter of which is a component of PM2.5. The forest canopy also acts as a depositional sink for air pollutants. All these processes are meteorologically influenced. We present here a first step at coupling information on tree species planting suitability and other planting constraints with data on UK-specific BVOC emission rates and tree canopy data to simulate via the WRF-EMEP4UK high spatial resolution atmospheric chemistry transport model the impact on UK air quality of four potential scenarios. Our ‘maximum planting’ scenarios are based on planting areas where yields are predicted to be ≥50 % of the maximum from the Ecological Site Classification Decision Support System (ESC-DSS) for Eucalyptus gunnii, hybrid aspen (Populus tremula), Italian alder (Alnus cordata) and Sitka spruce (Picea sitchensis). The additional areas of forest in our scenarios are 2.0 to 2.7 times current suggestions for new bioenergy and afforestation landcover in the UK. Our planting scenarios increase UK annual mean surface ozone concentrations by 1.0 ppb or 3 % relative to the baseline landcover for the highest BVOC emitting species (e.g., E. gunni). Increases in ozone reach 2 ppb in summer when BVOC emissions are greatest. In contrast, all the additional planting scenarios lead to reductions in UK annual mean PM2.5 – ranging from -0.2 µg m-3 (-3 %) for Sitka spruce to -0.5 µg m-3 (-7 %) for aspen – revealing that PM2.5 deposition to the additional forest canopy area more than offsets additional SOA formation. Relative decreases in annual mean PM2.5 are greater than the relative increases in annual mean ozone. Reductions in PM2.5 are least in summer, coinciding with the period of maximum monoterpene emissions. Although only a first step in evaluating the impact of increased forest plantation on UK air quality, our study demonstrates the need for locally relevant data on landcover suitability, emissions and meteorology in model simulations.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.5194/acp-23-13713-2023
UKCEH and CEH Sections/Science Areas:	Atmospheric Chemistry and Effects (Science Area 2017-)
ISSN:	1680-7324
Additional Information. Not used in RCUK Gateway to Research.:	Open access paper - full text available via Official URL link.
NORA Subject Terms:	Ecology and Environment Atmospheric Sciences Data and Information
Related URLs:	Other Other
Date made live:	03 Nov 2023 12:52 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/535407

Actions (login required)

View Item

Document Downloads

More statistics for this item...