Actions on black carbon – a short term complement to mitigate Arctic warming
Black carbon – a short-lived climate forcer that arises primarily from wood burning stoves and diesel engines and generators – intensifies climate warming, especially in the Arctic. Reduced emissions can have an immediate positive effect on the climate but coordinated policy action is required from across the northern hemisphere. New European-funded science-to-policy initiative shows how measures can be targeted.
– Action to reduce black carbon is a complement to action on carbon dioxide, not an alternative quick fix. Yet, reducing the emissions of black carbon would slow down the rate of Arctic warming until action on carbon dioxide kicks in, says Stefan Åström, researcher at IVL Swedish Environmental Research Institute and participant in the EU project Action on Black Carbon in the Arctic, EUA-BCA.
These dark particles, more commonly named soot, absorb heat. Emissions of black carbon throughout Asia, Europe and North America warm the atmosphere and this heated air is transferred to the Arctic. Emissions that occur in the Arctic region itself, however, have an even greater climate impact because when black carbon is deposited on snow it reduces the ability of snow and ice to reflect the sun’s rays and thereby contribute extra to melting.
Apart from their impact on climate, black carbon particles in the air are in many situations even more important as a contributing factor to public health effects such as shortened life expectancy as well as heart and lung diseases in people all over the world.
Positive results in a shorter-term than CO2
– Unlike carbon dioxide, the climate effect of black carbon depends, among other things, on where and under what season the emissions occur. Although gaps in knowledge remain, the research community has improved our understanding of the climate and health effects of short-lived climate forcers like black carbon. With what we know today, we can already see which source sectors are important and which measures will have a positive effect on the Arctic, says Simon Wilson of the Arctic Monitoring and Assessment Programme, and co-project manager for EUA-BCA.
Reduced emissions can give positive results in a shorter-term than actions on longer-lived substances such as carbon dioxide, and technical solutions to reduce emissions exist that could be used to a greater extent than today. But this requires urgent regional and global actions and stronger cooperation between actors and nations for the opportunities to be translated into practical actions.
– Reducing soot emissions is also beneficial to public health, potentially reducing the hundreds of thousands of premature deaths that are associated with fine particulate matter air pollution. Several measures to reduce emissions that exist today would therefore mean financial savings – both from increased resource efficiency, and reduced health costs says Simon Wilson.
Globally, the main sources of emissions are:
- Wood burning in homes, especially in open fires and older stoves
- Transport, mainly from older diesel engines
- The energy and industrial sector, including coal combustion
- Open biomass burning, including agricultural burning of crop residues and wildfires
- Flaring of gas at extraction sites and refineries
Wood burning is the largest source in Sweden
In the Arctic countries, emissions are dominated by the transport sector and by flaring, i.e., the combustion of excess gas with no useful energy production. In Sweden, wood burning accounts for the largest emissions.
– Replacing old boilers and stoves would reduce emissions of black carbon which is positive for both air quality and climate. It is also important to avoid incomplete combustion by using appropriate burning methods as well as fuels in stoves and boilers, says Stefan Åström.
To move forward, inventory methods and national reporting of emissions also need to be harmonized and quality assured. This requires a strong capacity build-up and an improved review of reported emissions, the report concludes.
Download the report: Enhancing the reduction of black carbon emissions to protect the Arctic Pdf, 1.6 MB.
For more information, please contact:
Stefan Åström, IVL Swedish Environmental Research Institute, phone: +46 10 788 67 55
Simon Wilson, Arctic Monitoring and Assessment Programme Secretariat, firstname.lastname@example.org
Zbigniew Klimont, International Institute for Applied Systems Analysis, IIASA, email@example.com
Mikael Hildén, Finnish Environment Institute SYKE, firstname.lastname@example.org
Petra Kestler, Environment Agency Austria, email@example.com