Methane emissions from the Munich Oktoberfest

Abstract

Abstract. This study presents the first investigation of the methane (CH4) emissions of a large festival. Munich Oktoberfest, the world's largest folk festival, is a potential source of CH4 as a large amount of natural gas for cooking and heating is used. In 2018 we measured the CH4 emissions of Oktoberfest using in situ measurements combined with a Gaussian plume dispersion model. Measurements were taken while walking and biking around the perimeter of the Oktoberfest premises (Theresienwiese) at different times of the day, during the week and at the weekend. The measurements showed enhancements of up to 100 ppb compared to background values and measurements after Oktoberfest. The average emission flux of Oktoberfest is determined as (6.7±0.6) µg (m2 s)−1. Additional analyses, including the daily emission cycle and comparisons between emissions and the number of visitors, suggest that CH4 emissions of Oktoberfest are not due solely to the human biogenic emissions. Instead, fossil fuel CH4 emissions, such as incomplete combustion or loss in the gas appliances, appear to be the major contributors to Oktoberfest emissions. Our results can help to develop CH4 reduction policies and measures to reduce emissions at festivals and other major events in cities. Furthermore, events with a limited duration have not yet been included in the state-of-the-art emission inventories, such as TNO-MACC, EDGAR or IER. Our investigations show that these emissions are not negligible. Therefore, these events should be included in future emission inventories.

Methane mapping, emission quantification, and attribution in two European cities: Utrecht (NL) and Hamburg (DE)

“…This ratio can vary depending on the mixture of gas compositions from different suppliers, but should meet the standards for gas compositions in the Netherlands (65 mol %-96 mol % for CH 4 and 0.2-11 mol % for C 2 H 6 ; ACM, 2018) and in Germany (83.64-96.96 mol % for CH 4 and 1.06-6.93 mol % for C 2 H 6 ; DVGW, 2013). Compressed natural gas vehicles can be mobile CH 4 emission sources (Nam et al, 2004;Curran et al, 2014;Naus et al, 2018;Popa et al, 2014), and in this study we also observed CH 4 signals from vehicles. For example, the point-to-point C 2 H 6 : CH 4 ratio (C 2 : C 1 ) calculated from road measurements of a car exhaust shown in Fig.…”

“…Zimnoch et al (2019) estimated CH 4 emissions of (6.2 ± 0.4) × 10 6 m 3 yr −1 for Kraków, Poland, based on data for the period of 2005 to 2008 and concluded that leaks from NGDNs are the main emission source in Kraków based on the carbon isotopic signature of CH 4 . Chen et al (2020) also showed that incomplete combustion or loss from temporarily installed natural gas appliances during big festivals can be the main source of CH 4 emissions from such events, while these emissions have not been included in inventory reports for urban emissions.…”

Assessing Urban Methane Emissions using Column Observing Portable FTIR Spectrometers and a Novel Bayesian Inversion Framework

“…Hence the EM27/SUN can be deployed and relocated quickly and inexpensively, while still adequately sampling the desired emission sources. Using multiple EM27/SUNs in an upwind-downwind configuration has been proven to be an effective way to measure methane emissions from dairy farms (Chen et al, 2016;Viatte et al, 2017) and coal mining areas (Luther et al, 2019), and some work has explored their usefulness in cities (Hase et al, 2015;Chen et al, 2020;Dietrich et al, 2020). There is also a coordinated effort to build a world wide network of these sensors (Frey et al, 2019).…”

“…Urban areas, which represent the majority of global anthropogenic greenhouse gas emissions (Hopkins et al, 2016), contain a mix of sources of methane, including landfills, industrial facilities, and fugitive emissions associated with natural gas infrastructure and end use. These fugitive emissions are a significant source of methane in some cities (Townsend-Small et al, 2012;McKain et al, 2015;Chen et al, 2020), but their detection and quantification is difficult (Phillips et al, 2013;Brandt et al, 2014). Governments have established goals for mitigating these emissions (Rosenzweig et al, 2010), creating a need for long term measurement systems to monitor progress and identify areas where action is needed (Gurney et al, 2015;Dietrich et al, 2020).…”

Assessing urban methane emissions using column-observing portable Fourier transform infrared (FTIR) spectrometers and a novel Bayesian inversion framework

“…These flights consisted of upwind and downwind transects of the city, as well as spirals in strategic locations. The ALAR was equipped with a Picarro model G2301-f cavity ring-down spectrometer (Crosson, 2008), which measured dry CO 2 and CH 4 concentrations in situ. High-frequency wind speed and direction data were also collected on the ALAR using the Best Air Turbulence (BAT) probe (Garman et al, 2006).…”