Global impacts of surface ozone changes on crop yields and land use

Abstract

h i g h l i g h t sWe estimate ozone impacts on crop yields using high and low air pollution scenarios. Substantial crop losses can be avoided by air pollution control, especially in Asia. Climate policies can have co-benefits for crops due to reduced co-emissions. Reduced ozone damage will also reduce land use and associated carbon emissions. a b s t r a c tExposure to surface ozone has detrimental impacts on vegetation and crop yields. In this study, we estimate ozone impacts on crop production and subsequent impacts on land use in the 2005e2050 period using results of the TM5 atmospheric chemistry and IMAGE integrated assessment model. For the crops represented in IMAGE, we compute relative yield losses based on published exposure-response functions. We examine scenarios with either constant or declining emission factors in a weak climate policy future (radiative forcing target of 6.0 W/m 2 at the end of the century), as well as co-benefits of stringent climate policy (targeted at 2.6 W/m 2 ). Without a large decrease in air pollutant emissions, higher ozone concentrations could lead to an increase in crop damage of up to 20% locally in 2050 compared to the situation in which the changes in ozone are not accounted for. This may lead to a 2.5% global increase in crop area, and a regional increase of 8.9% in Asia. Implementation of air pollution policies could limit crop yield losses due to ozone to maximally 10% in 2050 in the most affected regions. Similar effects can be obtained as a result of co-benefits from climate policy (reducing ozone precursor emissions). We also evaluated the impact of the corresponding land-use changes on the carbon cycle. Under the worst-case scenario analysed in this study, future ozone increases are estimated to increase the cumulative net CO 2 emissions between 2005 and 2050 by about 3.7 Pg C, which corresponds to about 10% of baseline land use emissions over the same period.

Tropospheric Ozone Assessment Report: Present-day tropospheric ozone distribution and trends relevant to vegetation

“…At the coarsest resolution, the distribution of areas identified in TOAR-Vegetation as having vegetation at low or high risk of damage from ozone largely matches that predicted by global modelling of M12, AOT40 or W126 (Avnery et al, 2011;Chuwah et al, 2015;Fuhrer et al, 2016;Hollaway et al, 2012;Van Dingenen et al, 2009;). However, the high values for ozone metrics in TOAR-Vegetation at SEA sites tend to be underestimated in modelling studies.…”

“…However, the high values for ozone metrics in TOAR-Vegetation at SEA sites tend to be underestimated in modelling studies. It is more difficult though to align measurements included in TOARVegetation with modelled data due to uncertainties introduced by comparing site-specific data with grid square values presented at resolutions of 2.8° × 2.8° (Avnery et al, 2011;Hollaway et al, 2012) or 3° × 2° (Chuwah et al, 2015). Differences in the years used also confound detailed comparisons as the global modelling studies tend to have used earlier years such as 2000 (Avnery et al, 2011;Fuhrer et al, 2016;Hollaway et al, 2012) or 2005(Chuwah et al, 2015 whilst TOAR-Vegetation provides 5-year means for the period 2010-2014.…”

Implications of Switching Fossil Fuel Subsidies to Solar: A Case Study for the European Union

“…Although the figures are not very high (0.32 and 1.47%, respectively), it is important to realize that they could entail some indirect damage. For instance, CO is a precursor for the formation of tropospheric ozone (O3), which has been proven to have impacts on health [25,26] and agricultural systems [27]. Moreover, OC emissions are also a key element for the deposition of PM2.5 in the atmosphere.…”

Ozone effects on photosynthesis of ornamental species suitable for urban green spaces of China

“…Studies over the past several decades indicated that chronic O 3 exposure significantly decreased the production of forests (Proietti et al, 2016), crops (Avnery et al, 2011;Ghude et al, 2014;Chuwah et al, 2015) and grasslands (Gilliland et al, 2016). However, there are some exceptions where O 3 exposure promoted biomass accumulation under particular environmental conditions (e.g.…”