The Concentration Of Methane In The Earth's Atmosphere Has Increased By 9% Over The Past 17 Years
Analysis of the concentration of methane in the Earth's atmosphere over the past seventeen years has shown that its share has increased by 9% during this time, reaching record high values, according to the research results published in the scientific journal Environmental Research Letters.
"The two main sources of this increase remain emissions related to the production and use of natural gas, as well as the livestock industry. Cows and other cattle produce almost as much methane as the entire oil and gas industry. People often joke about this, not understanding how much gas they emit," said one of the authors of the study, Professor Robert Jackson of Stanford University (USA).
According to climate scientists, the increase in average annual temperatures on Earth is primarily associated with an increase in the concentration of greenhouse gases, including CO2, methane, and nitrogen compounds. At the end of the nineteenth century, the concentration of carbon dioxide was 285 parts per million (ppm), while by the middle of the last century it had reached 315 parts per million. Now, this indicator is already above 400 ppm.
Because of this, most of the world's countries recognized the threat and signed a series of agreements, including the Paris accords, in which the world's leading industrial powers agreed to voluntarily reduce emissions and improve the efficiency of their economies.
These measures, as noted by Jackson and his colleagues, are primarily aimed at controlling CO2 emissions. They almost do not take into account the fact that there are other sources of greenhouse gases on Earth, in particular, methane and freons, which are produced in large quantities by agriculture and industry; this is especially true in developing countries.
Methane climate problem
According to Professor Jackson, this is since the cycle of methane in the atmosphere is very difficult to monitor. The problem is that this gas is destroyed very quickly under the influence of sunlight and ozone and oxygen molecules in the upper atmosphere. Besides, it is actively absorbed by the soil.
In the past, scientists believed that this process completely balances all methane emissions – both those generated by human activities and natural sources of this gas, such as swamps or geothermal sources. Jackson and his colleagues checked to see if this was true. The researchers studied in detail how the volume of methane emissions changed in the tropical and temperate latitudes of the Earth, and how actively its molecules were destroyed and absorbed.
The results of their work showed that the balance between the formation of new and splitting of old methane molecules was disrupted in the mid-2000s. Because of this, the concentration and total mass of this gas in the atmosphere began to grow rapidly, increasing by 50 million tons (9%) compared to the typical level of the beginning of the XXI century.
This is mainly because anthropogenic CH4 emissions from livestock and agriculture have increased by 11% over the past 17 years. Over the same period, the oil and gas industry and energy industry began to emit 15% more methane into the atmosphere. This has occurred in all regions of the world, except for Europe, where meat consumption has declined and measures have been taken to minimize methane emissions.
So far, scientists can't say whether these emissions have decreased this year due to the COVID-19 epidemic, as happened in China. However, they doubt that this happened, since the level of energy consumption and food production has not changed much. Climate scientists hope that the data they collect will encourage governments around the world to actively monitor methane emissions and take measures to minimize them.