A package of 16 measures could, if fully implemented across the globe, save close to 2.5 million lives a year; avoid crop losses amounting to 32 million tonnes annually and deliver near-term climate protection of about half a degree C by 2040.
The report estimates that implementing these measures would help keep a global temperature rise below the 2 degrees C target, at least until mid-century.
The measures, outlined in a new report compiled by the UN Environment Programme (UNEP) with an international team of experts, target short-lived climate forcers (SLCFs)—black carbon which is a major component of soot, methane and tropospheric ozone.
The report, funded by the Government of Sweden, estimates that around half of the black carbon and methane emission reductions can be achieved through measures that result in cost savings over the lifetime of the investment.
This is because some of the measures—such as recovering rather than emitting natural gas during oil production—allow the methane to be harvested as a clean source of fuel.
Cutting black carbon emissions by, for example, replacing inefficient cookstoves and traditional brick kilns with more efficient ones, also cuts fuel costs for households and kiln operators.
In total, nine priority measures are identified for reducing black carbon emissions, with substantial benefits to health and the environment
A switch from traditional biomass cookstoves to more efficient fan-assisted ones, or stoves fueled by Liquefied Petroleum Gas or biogas, offers the biggest reduction potential in Africa, Asia Pacific and, to some extent, in Latin America and the Caribbean.
Action on cookstoves is also pinpointed as a low cost or cost-saving measure, which would represent close to 25 per cent of the total climate benefit, achievable through the full implementation of all 16 measures on short-lived climate forcers.
A switch to more efficient cookstoves would save householders and communities the time and money, usually spent over the collection and purchase of firewood and other sources of fuel.
The cost of replacing traditional cookstoves with more environmentally-friendly ones may seem low by international standards. However, from the perspective of local users in developing countries, this cost may represent a financial burden.
The report looks at ways to overcome such barriers and to link the implementation of such measures to national development plans.
Replacing conventional residential wood burning stoves in North America and Europe with pellet stoves and boilers would also offer important black carbon cuts—estimated at close to 2 per cent of the overall climate benefits.
Replacing traditional brick kilns with more efficient ones could trigger cost savings equal to around $7 a tonnes of CO2 equivalent.
Vertical-shaft brick kilns use about half the energy and, hence half the fuel costs, per brick made compared to the traditional kilns.
Methane Cuts to Reduce Tropospheric Ozone
In respect to methane, seven measures are identified.
The biggest cuts would come from reducing emissions from coal mines and processes related to the production and transport of oil and gas, as well from as the capture of methane from landfill sites.
Globally, nearly 50 per cent of the methane reduction potential can be achieved through measures that will give rise to cost savings over the lifetime of the investment.
What is black carbon?
Black carbon (BC) exists as particles in the atmosphere and is a major component of soot. BC is not a greenhouse gas. Instead it warms the atmosphere by intercepting sunlight and absorbing it. BC and other particles are emitted from many common sources, such as cars and trucks, residential stoves, forest fires and some industrial facilities. BC particles have a strong warming effect in the atmosphere, darken snow when they are deposited, and influence cloud formation. Other particles may have a cooling effect in the atmosphere and all particles influence clouds. In addition to having an impact on climate, anthropogenic particles are also known to have a negative impact on human health.