Climatologists studied ice samples that formed in Antarctica in the mid-19th century and concluded that the concentration of hydrogen in the air has increased by more than 70% over the past century and a half. This growth has further accelerated global warming, scientists write in an article in the journal PNAS.
“Our reconstruction shows that the proportion of hydrogen in the atmosphere remained almost unchanged until the end of the 19th century, after which it began to grow smoothly and grew by 70% by the beginning of this century. In addition, we recorded a sharp surge in hydrogen concentration at the end of the last century, whose existence casts doubt on the link between anthropogenic emissions of carbon monoxide and hydrogen, "the researchers write.
Hydrogen is a very light gas that actively interacts with oxygen and other oxidants. Today hydrogen is considered as a substitute for fuel based on petroleum products or natural gas, since its combustion does not lead to the accumulation of greenhouse gases and various toxins in the atmosphere.
On the other hand, hydrogen itself is a greenhouse gas, as its entry into the lower atmosphere slows down the decay of methane and contributes to the formation of ozone, whose molecules prevent heat from leaving the Earth. According to the current estimates of scientists, hydrogen is significantly inferior to carbon dioxide in its effect on the climate, but its role may increase significantly after the transition of civilization to hydrogen energy.
A group of climatologists led by Eric Zaltzman, professor at the University of California at Irvine (USA), received the first information about how the concentration of hydrogen in the Earth's atmosphere changed over the past century and a half. Scientists obtained similar information by analyzing the chemical composition of air bubbles trapped in ice deposits in Antarctica.
Hydrogen pollution of the atmosphere
The first serious observations of the concentration of hydrogen in the atmosphere, as noted by Professor Salzman and his colleagues, were organized at the global level only in the late 1980s. For this reason, scientists could not say for sure at what rate hydrogen accumulates in the Earth's air and what industrial processes generate its emissions.
Scientists managed to obtain such information thanks to the unique ice deposits that have been formed since 1852 on the territory of "megadunes", undulating deposits of compressed snow in East Antarctica. They are located in a region with extremely low rainfall, so that a relatively thin layer of ice 60-70 meters thick contains layers that have formed over many decades.
Climatologists collected ice samples from different regions of the "megadunes", extracted air bubbles from such layers and studied their chemical composition in detail. Their analysis has shown that the concentration of hydrogen in the atmosphere has increased dramatically over the past 150 years. It has increased by about 70%, and all this growth has occurred in the last hundred years.
Measurements by Professor Zaltsman and his colleagues indicated that the concentration of hydrogen increased especially rapidly in the last two decades of the XX century. The discovery came as a surprise to scientists, as researchers in the past believed that the main source of these leaks was the production of so-called synthesis gas, a mixture of hydrogen and carbon monoxide.
Its production began to decline in the 1980s, leading many scientists to believe that atmospheric hydrogen concentrations should have dropped in a similar way. Ice samples from Antarctica indicate that this is not actually the case, suggesting that there are other significant sources of anthropogenic hydrogen emissions. Their search and study should become one of the main tasks for climatologists, the researchers concluded.