2023-05-16 09:32:06
When we burn fossil fuels, it’s not just greenhouse gases that go up in smoke. There are also a whole bunch of other particles including carbon black. Soot whose effects on global warming may well have been underestimated.
You will also be interested
[EN VIDÉO] Earth is darkening due to global warming and that’s not good news For 20 years, the albedo of the Earth has decreased by 0.5%. As she thinks less…
Our climate is warming. Mainly because of our devouring appetite for fuelsfuels fossils. Because by burning them, we emit greenhouse gases (GHG). But also, of which we are probably even less aware, all kinds of aerosol particles. And in particular a few percent of what researchers call the black of carbonecarbone.
Carbon black is mostly GoGo which has the unfortunate tendency – unfortunate especially in the context of global warmingglobal warming – to absorb and store the heatheat of soleilsoleil. Adding a bit more to the impact of greenhouse gasgreenhouse gas in L’atmosphereatmosphere. But that’s not all. Because carbon black, when it sits on light surfaces like snow, decreases their ability to radiate heat back into space. Increasing, here too, the impacts of GHGs.
An accurate estimate of the warming effect
“Understanding the interaction between carbon black and lightlight sunlight is of fundamental importance in climate research”says Assistant Professor Nobuhiro Moteki of the Department of Life Sciences TerreTerre and planets from the University of Tokyo (Japan), in a communiqué. The data that was especially lacking in the mattermatter to the researchers, it was that of the refractive index of carbon black. The way it reflects light rays.
To calculate it, researchers at the University of Tokyo isolated carbon black particles captured in water. Enough to work on pure soot and obtain measurements of unparalleled precision. And their results are not reassuring. They show that the values on which scientists have relied so far may have been underestimated by as much as 16%. So to refine the climate models, the Japanese researchers now recommend not only to integrate these new values, but also to apply their method to the identification of other potential particles with optical properties still unknown in our atmosphere, in the ocean or in ice cream.
Global warming: soot, an aerosol more powerful than it seems
Soot would have twice the impact on climate change than expected. Its warming power is even greater than that of methane. Why then not fight against his emissionsemissions to limit future temperature increases?
Article by Quentin Mauguit published 01/16/2013
THE Diesel enginesDiesel engines, coal-fired power plants and bushfires all have one thing in common: they emit soot into the atmosphere. These carbonaceous particles only measure a few tens of nanometersnanometers in diameter, but their effects on human health are undeniable. The International Center for Research on cancercancer (IARC) has classified soot in the group of certain carcinogens for humans. Beyond this health aspect, the compounds from the combustioncombustion incomplete fossil fuels or biomass also play a considerable role in our climate, in particular because they absorbenergyenergy solar.
About 7,500 gigagrams (Gg) of black carbon would have been released into the atmosphere in 2000, but it should be noted that the error range extends from 2,000 to 29,000 Gg. The implication of these particles in global warming has already been studied by many models… but it would have been underestimated by half. This information has just been revealed in a 232-page report published in the Journal of Geophysical Research: Atmospheres (JGR).
Soot, a new target for attacking global warming
Within theInternational Global Atmospheric Chemistry Project (igac), 31 scientists participated in the drafting of this document, which concludes four years of research. The role of soot has been studied through models and field observations in all its facets. The researchers took into account the accumulation of these aerosols in the atmosphere and their absorbency, but also, for example, the impact of their deposits on snow or ice. In the end, the total radiative forcing of black carbon during the industrial era was estimated at 1.1 W/m2with a 90% uncertainty ranging from 0.17 to 2.10 W/m2. This value is, according to the authors, twice as large as those provided by most of the models developed to date.
As a direct consequence, soot emissions would become the second most anthropogenic factor influencing global warming, just behind the indomitable CO2. Methane was therefore relegated to third place on this podium. The impact of black carbon on our climate would be comparable, according to the new figures, to 66% of that of carbon dioxide. It should be noted, however, that the researchers took into account the effects of all the substances emitted into the atmosphere by a specific mode of combustion (the use of coal, for example, releases sulphidessulphideswhich contribute to the cooling of our planet).
There is a noticeable difference between CO2 and soot. The first persists for several decades in the atmosphere, while the second does not last more than 7 to 10 days. Therefore, new policies aimed at reducing the massive atmospheric release of carbonaceous particles could have substantial and above all rapid results on our climate. According to Piers Forster of the University of Leeds, we could gain 20 years of respite from the ongoing fight against climate change. This report also confirms the results of David Shindell’s work, which was published in January 2012 in the journal Science : fighting methane and soot would be more effective in limiting global warming than reducing CO emissions2. Moreover, any efforts to limit black carbon emissions can only improve the health of millions of people around the world.
1684230877
#littleknown #phenomenon #real #impact #climate #change