The atmospheric concentration of greenhouse gases, including carbon dioxide, broke records in 2018 and went on to reach new highs.
The report conducted by the World Meteorological Organisation stated that the increase in carbon dioxide was just over the average rise which has been recorded in the last decade. Other greenhouse gases such as nitrous oxide and methane have also increased more than the average amounts. Long lived greenhouse gases have led to a 43 percent increase in the global warming effect since 1990.
The report doesn’t look at emissions but instead at the concentration of each gas in the atmosphere. The difference between these two are that emissions is the amount of each gas that has been added to the atmosphere from activities such as burning fossil fuels for electricity or deforestation. Whereas total concentration is the amount left of each gas once a series of complex interactions take place, which can lead to a reduction in the amount of a certain gas. For example, about 25% all carbon emissions end up being absorbed by the sea, and similar numbers get absorbed by the trees and land.
The researchers used monitoring stations all over the world, even in the arctic. These stations stated that in 2018 the concentration of carbon dioxide in the world’s atmosphere was 407.8 parts per million, compared to 405.5 parts per million in 2017.
The increase between these two years was more than the average in the last 10 years but more astonishingly, it is 147 percent more than what is was in 1750, the preindustrial era.
The World Meteorological Organisation also take data for gases such as methane or nitrous oxide. Around 40% of the Earth’s atmosphere comes from natural sources, e.g. wetlands, and the other 60% comes from human activities such as landfill dumps, rice cultivation or cattle farming. Methane is currently at 259% of the preindustrial level of 1750, and the increase in methane in the past year was more than the two previous and the average for the past decade.
Nitrous oxide, similarly, has had a large increase with now over 123% more nitrous oxide in the atmosphere than there was in 1750. Nitrous oxide is emitted from fertilisers that are used for farming but also from the oceans and it also had an increase in the last year larger than the average for the previous 10.
The biggest concern to scientists is the effect on global warming these increased concentrations will have. This effect is known as radiative forcing, and since 1990 it has already increased 43%, without showing any signs of slowing down.
Despite all the commitments made under the Paris agreements, there has been no indications of the levels of greenhouse gases reducing in the Earths atmosphere. The commitments made in the agreement need to be acted upon otherwise they may as well not exist. If they are not acted upon it puts the future of welfare of mankind at risk.
The last time the Earth had comparable carbon dioxide concentration levels is predicted to be about 3 to 5 million years ago. During these times temperatures and sea levels were notably higher, with temperatures being 2 to 3 degrees Celsius warmer and sea levels about 10 to 20 metres higher than currently. This means that the world could be heading for conditions like this unless serious action is taking by some of the worlds leading nations.