Photo: Carlo Allegri Getty Images Agence France-Presse
The fires in the summer in California, illustrate very well the consequences of global warming.
The years go by and the thermometer global continues to climb dangerously. New scientific data published on Monday show that the past four years have been the warmest ever recorded. The average global temperature is now higher by 1.1 °C compared to the situation that prevailed before the industrial era and the development of human activity based on the burning of fossil fuels.
The portrait of climate published by the european programme of Earth observation Copernicus is formal : “The last four years have been the warmest ever recorded “, 2018, being in the fourth position, with a temperature of 0.4 °C higher than the average of 1981-2010.
“In 2018, we have once again seen a year of very hot. The weather events are dramatic, such as the warm and dry summer in many parts of Europe or the increase of the temperature around the areas of the Arctic are alarming signals for all of us “, a summary on Monday, the director of Copernicus, Jean-Noël Thépaut, at the time of the publication of the data.
According to this scientific analysis, the first to reveal the complete data for the year 2018, “the global warming more pronounced” compared to the average for 1981-2010 has been observed in the Arctic, a vast region where the thermometer climbs quickly.
This observation is all the more worrisome that the cast understood the permafrost covering 25 % of the nordic regions is expected to release very large quantities of greenhouse gases, including methane. This permafrost, which has already begun to melt because of climate change, would contain at least the equivalent of 15 years of greenhouse gas emissions in the world.
What’s more, the warming observed in the North accelerates the melting of Greenland’s ice, which is disappearing today at a level 50 % higher than before the industrial era, concluded in December, a study published in the scientific magazine Nature.
This situation could accelerate the increase in the level of the oceans to such an extent that” it will not be possible to adapt to them “, warned the co-author of the study, Michiel van den Broeke, in an interview to the Guardian. If all the ice in Greenland melted, the sea level would rise by seven metres.
The level of these same oceans is already mounting, in particular, because they absorb 90 % of the heat generated by the greenhouse gas emissions from human activity, the equivalent of three to six atomic bombs every second, according to a calculation published by The Guardian on Monday.
To the bar of the 1.5 °C
The new data published by Copernicus demonstrated that the trajectory of current climate we are ever closer to a global warming of 1.5 °C, which is the goal — not-to-exceed — the most ambitious set in the framework of the Paris Agreement. The planet has already increased by 1.1 °C compared to temperatures that prevailed prior to the industrial era.
This increase in the thermometer world has nothing trivial, according to the UN : “climate change is already affecting people, ecosystems and livelihoods in the world, with effects such as floods or droughts, which fall disproportionately on the poorest and most vulnerable “.
Moreover, a shift “without precedent” will be necessary to avoid exceeding a global warming of 1.5 °C, finds the latest report of the intergovernmental panel on climate change (IPCC). To achieve this, humanity should reduce its CO2 emissions by 45 % by 2030, and then make it completely disappear by 2050. A scenario that would avoid the worst of it, but that would involve leaving them in the ground the vast majority of oil reserves are known, according to scientists.
The international community is, however, very far from the account, according to the IPCC. The current commitments of the States signatories of the Paris Agreement lead the world to an average temperature rise of over 3 °C. A situation that would cause an increase in extreme climatic events, a reduction of areas for cultivation and water resources in several regions, the influx of millions of climate refugees and the disappearance of panels of major of the world’s biodiversity.
CO2 on the rise
Despite the scientific evidence, the representatives of 196 countries failed to agree to increase their ambition on climate during the recent UN conference on climate, COP24, last December.
The analysis of Copernicus points out, moreover, that the concentration of CO2 in the atmosphere continues to rise, due to our dependence on fossil fuels. It has achieved 406,7 parts per million (ppm) in 2018, breaking once again the record of the previous year.
The problem is that the threshold of 400 ppm is a genuine alarm signal, according to the IPCC, which considers that, to achieve limiting global warming to between 2 °C and 2.4 °C compared to the preindustrial era, it is necessary that the concentration of CO2 tops out between 350 and 400 ppm.
Until the industrial revolution, this rate had not exceeded 300 ppm for at least 800,000 years. But at the current pace, the bar of 450 ppm could be achieved within 20 years, according to the national service in the british weather. It would then be impossible to limit the dramatic changes in the global climate.