From the Arctic to the Himalayas, black carbon is a super pollutant of the atmosphere with impacts on human health and ecosystems.
O Black carbon is one of the oldest pollutants in history, with a devastating impact on health, climate and ecosystems. From the saturated atmosphere in Asian cities to the melting of Arctic ice and Himalayan glaciersit is a ubiquitous super pollutant.
“It is the oldest pollutant in the world. The first human who tamed fire in his cave breathed black carbon,” Xavier Mari, biogeochemist, research director at the Institute for Development Research (IRD) in Bangkok, told AFP.
Black carbon or soot is formed during incomplete combustion of biomass (wood, green waste) or fossil fuels (coal, oil, gas).
It comes from home and kitchen heating (43% of global emissions), of transport (23%) and the industry (11%), ccontributes to air pollution. Since the Industrial Revolution, emissions of this pollutant have increased tenfold, although they have registered a slight reduction since their peak in the 2010s.
Although it only remains in the atmosphere for around 12 days, black carbon seriously affects the health of populations in South Asia and Africa.
“These are fine particles that penetrate deep into the lungs,” warns Bertrand Bessagnet, air quality manager at in Nepal. These particles are linked to serious problems such as heart disease and lung cancer.
With 1,500 times more heating power than CO2
Harmful to health, black carbon also has a heating power up to 1,500 times greater than that of carbon dioxide (CO2)according to of the United Nations Environment Program (UNEP).
“Due to their black color, these particles absorb light and store it as heat”explains Xavier Mari.
This effect amplifies ice melting in sensitive areas such as the Himalayas, Alps and Arctic. Carried by the wind, black carbon is deposited at the top of Himalayan glaciers and reaches the poles. Once covered in soot, these normally white surfaces lose their that is, its ability to reflect solar radiation.
In the French Alps, for example, “black carbon”, combined with Saharan dust, accelerates melting: this phenomenon has reduced the duration of snow cover by 17 days over the past four decades. It also anticipates the peak spring melt, according to a
“Only small amounts of black carbon are needed to have an impact on the color of the snow and therefore on the melting of the snow,” explains Marie Dumont, head of the snow study center (CNRS/Météo France) and co-author of the study.
This early melting “disturbs the balance of fragile mountain ecosystems” and may also have repercussions in agriculture and hydroelectric production.
black carbon contaminates all the world’s oceans
This alliance that brings together 23 NGOs call for the adoption of binding regulations in order to drastically reduce “black carbon” emissions from ships sailing in the Arctic.
Even worse, black carbon enters the food chainfrom zooplankton to mammals and has even been detected in newborn babies, as it crosses the placenta.
Europe sets a good example
Despite the worrying scenario, there are signs of progress. In Europe, black carbon emissions have decreased significantly since the 2000swhich helped to partially mitigate the impact of global warming on the melting of snow cover.
