Details

Autor(en) / Beteiligte

• Metya, Abirlal
• Datye, Amey
• Chakraborty, Supriyo
• Tiwari, Yogesh K.
• Patra, Prabir K.
• Murkute, Charuta

Titel

Methane sources from waste and natural gas sectors detected in Pune, India, by concentration and isotopic analysis

Ist Teil von

• The Science of the total environment, 2022-10, Vol.842, p.156721-156721, Article 156721

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Methane (CH4) is a potent greenhouse gas and also plays a significant role in tropospheric chemistry. High-frequency (sub-hourly) measurements of CH4 and carbon isotopic ratio (δ13CH4) have been conducted at Pune (18.53°N, 73.80°E), an urban environment in India, during 2018–2020. High CH4 concentrations were observed, with a mean of 2100 ± 196 ppb (1844–2749 ppb), relative to marine background concentrations. The δ13CH4 varied between −45.11 and −50.03 ‰ for the entire study period with an average of −47.41 ± 0.94 ‰. The diurnal variability of CH4 typically showed maximum values in the morning (08:00–09:00 local time) and minimum in the afternoon (15:00 local time). The deepest diurnal amplitude of ~500 ppb was observed during winter (December–February), which was reduced to less than half, ~200 ppb, during the summer (March–May). CH4 concentration at Pune showed a strong seasonality (470 ppb), much higher than that at Mauna Loa, Hawaii. On the other hand, δ13CH4 records did not show distinct seasonality at Pune. The δ13CH4 values revealed that the significant sources of CH4 in Pune were from the waste sector (enhanced during the monsoon season; signature of depleted δ13CH4), followed by the natural gas sector with a signature of enriched δ13CH4. Our analysis of Covid-19 lockdown (April to May 2020) effect on the CH4 variability showed no signal in the CH4 variability; however, the isotopic analysis indicated a transient shift in the CH4 source to the waste sector (early summer of 2020). [Display omitted] •Methane concentration and isotopic values were measured the first time in India.•Methane concentration but not the isotopic values shows seasonality in Pune.•Isotopic analysis shows waste sector is the significant source of methane in Pune.•No lockdown effect was found on methane records.