Environmental Sustainability

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Browsing Environmental Sustainability by Subject "13 Climate Action"

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    Comment on ‘Estimating methane emissions from manure: a suitable case for treatment?’
    (IOP Publishing, 2025-06-01) Anthony, Steven G.; Cardenas, Laura C.; Gilhespy, Sarah L.; Sandars, Daniel L.; Chadwick, David R.
    Ward et al (2024 Environ. Res. 1 025003) recently published a paper in this journal (Ward et al 2024 Environ. Res. 1 025003) asserting that methane emissions from manure management in the United Kingdom Inventory of Greenhouse Gas emissions could be under-estimated by a factor of four to five. This was based on extrapolation of measurements from two farms located in the south-west of England where manure management is purposely set-up to encourage methane release and capture, for use as a fuel source. We argue that methane thus extracted cannot be compared with the quantities emitted to the atmosphere on a typical farm which is what the national Inventory seeks to estimate, and show that existing Inventory calculations are consistent with wider literature and typical management practices in the United Kingdom.
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    Optimizing the temperature sensitivity of the isoprene emission model MEGAN in different ecosystems using a Metropolis‐Hastings Markov Chain Monte Carlo method
    (American Geophysical Union (AGU), 2025-05-01) DiMaria, Christian A.; Jones, Dylan B. A.; Ferracci, Valerio; Bloom, A. Anthony; Worden, Helen M.; Seco, Roger; Vettikkat, Lejish; Yáñez Serrano, Ana Maria; Guenther, Alex B.; Araujo, A.; Goldstein, Allen H.; Langford, Ben; Cash, James; Harris, Neil R. P.; Brown, Luke; Rinnan, Riikka; Schobesberger, Siegfried; Holst, Thomas; Mak, John E.
    Isoprene is a reactive hydrocarbon emitted to the atmosphere in large quantities by terrestrial vegetation. Annual total isoprene emissions exceed 300 Tg a−1, but emission rates vary widely among plant species and are sensitive to meteorological and environmental conditions including temperature, sunlight, and soil moisture. Due to its high reactivity, isoprene has a large impact on air quality and climate pollutants such as ozone and aerosols. It is also an important sink for the hydroxyl radical which impacts the lifetime of the important greenhouse gas methane along with many other trace gas species. Modeling the impacts of isoprene emissions on atmospheric chemistry and climate requires accurate isoprene emission estimates. These can be obtained using the empirical Model of Emissions of Gases and Aerosols from Nature (MEGAN), but the parameterization of this model is uncertain due in part to limited field observations. In this study, we use ground‐based measurements of isoprene concentrations and fluxes from 11 field sites to assess the variability of the isoprene emission temperature response across ecosystems. We then use these observations in a Metropolis‐Hastings Markov Chain Monte Carlo (MHMCMC) data assimilation framework to optimize the MEGAN temperature response function. We find that the performance of MEGAN can be significantly improved at several high‐latitude field sites by increasing the modeled sensitivity of isoprene emissions to past temperatures. At some sites, the optimized model was nearly four times more sensitive to temperature than the unoptimized model. This has implications for air quality modeling in a warming climate.
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    ItemOpen Access
    Predicted yield and soil organic carbon changes in agroforestry, woodland, grassland, and arable systems under climate change in a cool temperate Atlantic climate
    (Springer, 2025-05) Giannitsopoulos, Michail L.; Burgess, Paul J.; Graves, Anil R.; Olave, Rodrigo J.; Eden, Jonathan M.; Herzog, Felix
    The impact of a changing climate on crop and tree growth remains complex and uncertain. Whilst some areas may benefit from longer growing seasons and increased CO2 levels, others face threats from more frequent extreme weather events. Models can play a pivotal role in predicting future agricultural and forestry scenarios as they can guide decision-making by investigating the interactions of crops, trees, and the environment. This study used the biophysical EcoYield-SAFE agroforestry model to account for the atmospheric CO2 fertilization and calibrated the model using existing field measurements and weather data from 1989 to 2021 in a case study in Northern Ireland. The study then looked at two future climate scenarios based on the representative concentration pathways (RCP 4.5 and RCP 8.5) for 2020–2060 and 2060–2100. The predicted net impacts of future climate scenarios on grass and arable yields and tree growth were positive with increasing CO2 fertilization, which more than offset a generally negative effect of increased temperature and drought stress. The predicted land equivalent ratio remained relatively constant for the baseline and future climate scenarios for silvopastoral and silvoarable agroforestry. Greater losses of soil organic carbon were predicted under arable (1.02–1.18 t C ha−1 yr−1) than grassland (0.43–0.55 t C ha−1 yr−1) systems, with relatively small differences between the baseline and climate scenarios. However, the predicted loss of soil organic carbon was reduced in the long-term by planting trees. The model was also used to examine the effect of different tree densities on the trade-offs between timber volume and understory crop yields. To our best knowledge this is the first study that has calibrated and validated a model that accounts for the effect of CO2 fertilization and determined the effect of future climate scenarios on arable, grassland, woodland, silvopastoral, and silvoarable systems at the same site in Europe.