Methane, comes from several natural and anthropogenic sources. It is an important contributor to global warming because it traps heat in the atmosphere. It is also involved in ground-level formation of ozone, which is an air pollutant and bad for human health. Methane’s atmospheric lifetime — around 12 years — is much shorter than that of carbon dioxide, which lingers for more than a century. But methane is, per unit, more than 20 times as potent as CO2 as a greenhouse gas.
Atmospheric concentrations of the gas — 1,897 parts per billion in September 2021 — are now more than 2.5 times above pre-industrial levels. This increase is predominantly due to agriculture and fossil fuel use. Source: Nature 2020
Over the past 800,000 years, concentrations of nitrous oxide in the atmosphere rarely exceeded 280 ppb. Levels have risen since the 1920s, however, reaching a new high of 335 ppb in 2021. This increase is primarily due to agriculture.
The rapid global expansion of the electric power industry, mainly in Asia, have increased the demand for sulfur hexafluoride (SF6)-insulated switchgear, circuit breakers, and transformers. The large bank of SF6 sequestered in this electrical equipment provides a substantial source of emissions from maintenance, replacement, and continuous leakage. Other emissive sources of SF6 occur from the magnesium, aluminium, and electronics industries as well as more minor industrial applications. Source EGU 2020
Credit: Ted Wood / Cavan