They are called short-lived climate forcers and they contribute to both pollution and climate change. What are they and why are they so important to health and climate?
Greenhouse and pollutant emissions are closely linked. some pollutants are also greenhouse gases and act much faster than CO2.
To many people, however, the difference is not clear, but also the indirect link between greenhouse gases that act on the climate in the long term and air pollution, which is directly harmful to humans, ecosystems and even agriculture.
Crucial to combating climate change and pollution is the little-known role of Short-Lived Climate Pollutants (SLCPs). Here are what the main short-lived climate pollutants are.
Ozone and CFC
Ozone is an emblem of how man is able to make opposite damages to his own house, the Earth. The stratospheric ozone protects us from ultraviolet rays, in the 1980’s the problem of the hole in the ozone layer was in the limelight, but it was curbed by the Montreal Protocol in 1988 which banned the CFC gases used in aerosol cans and as refrigerants which are responsible for it.
The substitutes of CFCs, which are also greenhouse gases, HCFCs, are even more powerful and effective greenhouse gases, 20000 times more than CO2. Small quantities have a significant impact on the Earth’s energy balance. It is therefore essential to regulate and reduce them. But it doesn’t end here.
Ozone is also a greenhouse gas, decreasing in the stratosphere it would have a slight cooling, but on the contrary ozone is formed in the low layers of the troposphere especially in summer as a secondary photochemical pollutant and is therefore a warming factor of the climate.
Tropospheric ozone is not only irritating to health, but it also damages agricultural production. It is estimated that acting for its reduction would avoid the loss of production of 50 million tons of cereals. Moreover, ozone pollution also causes an impoverishment of the nutritional value of wheat and other cereals.
Soot and black carbon
This pollutant is also a short-lived atmospheric climate forcer, meaning it acts on climate in a matter of days or weeks. Equally, reducing them would have almost immediate effects in containing global warming, as well as benefits on health and even sea ice and levels.
The climatic effects of black carbon are mainly regional or macro-regional. Important however are some global side effects, for example with transboundary transport due to large scale winds it arrives and then is deposited in the form of soot on mountain and even polar glaciers. The effect is deadly, in fact soot deposition accelerates the loss of sea ice and the melting of alpine and mountain glaciers. Even mitigating black carbon emissions could limit sea level rise by 20%.
Methane
Methane is not an environmentally friendly fuel at all. It is not a direct pollutant, but with combustion it produces greenhouse gases and in addition its short-term warming effect is also 100 times greater than CO2.
Methane accounts for 16% of global greenhouse emissions and comes from livestock, especially large livestock, oil and gas production and distribution, coal mining, landfills and rice cultivation. Reducing methane emissions also improves local air quality because it reduces volatile organic compounds, precursors to the formation of tropospheric ozone.
This pollutant is also a short-lived atmospheric climate forcer, meaning it acts on climate in a matter of days or weeks. Equally, reducing them would have almost immediate effects in containing global warming, as well as benefits on health and even sea ice and levels.
The climate effects of black carbon are primarily regional or macro-regional. Important however are some global side effects, for example with transboundary transport due to large scale winds it arrives and then is deposited in the form of soot on mountain and even polar glaciers. The effect is deadly, in fact soot deposition accelerates the loss of sea ice and the melting of alpine and mountain glaciers. Even mitigating black carbon emissions could limit sea level rise by 20%.
Thanks to this agreement, 195 countries have adopted the first legally binding universal agreement on the global climate. The agreement’s objective (to limit the average increase in global temperature to well below 2°C, while seeking to reduce it to 1.5°C, compared to pre-industrial levels) is ambitious and cannot be achieved without a major overhaul of global energy production and consumption.
In support of the global climate agenda, the EU has adopted binding climate and energy targets for 2020 and proposed targets for 2030 as part of its overall efforts to move to a low-carbon economy and reduce greenhouse gas emissions by 80-95 % by 2050.
The first set of climate and energy targets for 2020 includes a 20 % reduction in emissions (compared to 1990 levels), a 20 % energy consumption from renewable sources and a 20 % increase in energy efficiency.
According to the current proposals under consideration by the EU institutions, the next 2030 target will include an update of these goals: emissions must be reduced by 40 %, 27 % of energy will have to come from renewable sources and energy efficiency will have to increase by 27 % (or 30 %, according to the European Commission’s recent proposal) over the baseline targets.
Decrease in overall greenhouse gas emissions
Measures taken to meet these targets are helping to reduce European emissions, which in 2015 were down about 22% from their level in 1990 and declined in all major sectors except for transport, refrigeration and cooling.
During this period, the largest reductions were seen, almost equally, in the industry and energy supply sectors.
According to recent EEA assessments of greenhouse gas emissions and energy (Trends and projections in Europe 2016), the EU is overall on track to meet its 2020 targets.
The pace of reductions is expected to slow after this year and more efforts will be needed to achieve the long-term goals. In particular, despite the improved fuel efficiency of cars and the increased use of biofuels, reducing overall emissions from transport in the EU has proven very difficult.
Some technological solutions, such as second-generation biofuels and carbon capture and storage, are expected to contribute to overall climate efforts, but it is unclear whether or not they can be implemented to the extent required and whether they are feasible and truly sustainable in the long term.
Effort Sharing Decision and EU Emissions Trading System
In terms of greenhouse gas (GHG) emission reductions, one of the cornerstones of the EU’s commitment is the Effort Sharing Decision, which sets binding annual greenhouse gas emission targets for all EU member states for 2020.
The decision covers sectors such as transport, construction, agriculture and waste, which account for about 55% of the EU’s total emissions.
National emissions targets have been set according to the relative wealth of member states, meaning that richer countries must reduce their emissions more than others, while some countries are allowed to increase their emissions from these sectors.
Overall, by 2020 the national targets will achieve a reduction of about 10% of total EU emissions from the sectors concerned compared to 2005 levels.
The remaining 45% of EU emissions (mainly from power plants and industrial installations) are regulated by the EU Emissions Trading System (EU ETS).
The EU ETS sets a cap on the total amount of greenhouse gases that can be emitted by more than 11,000 installations that are large energy consumers in 31 countries, including emissions from airlines operating between those States.
Under the system, companies receive or purchase emission allowances, which they can trade with others; heavy fines are imposed on companies that release emissions in excess of their allowances.
Over time, the system-wide cap is reduced to cause the total emissions to decrease.
By establishing a monetary value for carbon, the EU ETS creates incentives for companies to cut emissions in the most cost-effective way and invest in clean, low-carbon technologies.
The European Environment Agency monitors progress in reducing greenhouse gas emissions covered by the EU ETS.
Based on the most recent data and assessment, these emissions decreased by 24% between 2005 and 2015 and are already below the 2020 cap; the decrease is mainly due to less use of coal- and lignite- derived fuels and greater use of renewables for energy production.
Emissions from other industrial activities under the EU ETS have also declined since 2005, but have remained stable in recent years.
The European Commission recently proposed increasing the intensity of emission cuts from 2021, so that the sectors covered by the EU ETS would reduce their emissions by 43% by 2030 compared to 2005.
In the long run, looking beyond the 2030 targets, EU member states will be able to achieve greater reductions in GHG (greenhouse gas) emissions from the sectors covered by the effort sharing decision.
Without substantial efforts in these areas, the EU would fail to meet its 2050 target of cutting its emissions by 80 % from 1990 levels.