SuperPollutants

Cut Global Warming in Half & Save our Planet
by Stopping Greenhouse Super-pollutants

 The best and quickest way to slow the global temperature rise over the next 20 years and meet the target set at Paris is to reduce emissions of four short-lived climate pollutants (SLCP, also called “super greenhouse pollutants”) that warm way above their weight, but rapidly disappear from the atmosphere if we stop emitting them. The four SLCP are:

·      Methane, which traps 86 times as much heat in the first 20 years after emission as the same weight of CO2, but most of it decomposes into other substances within those 20 years.

·       Black carbon, which remains in the air for only a few weeks, but still causes thousands of times more global warming in the 20 years after emission as the same weight of CO2  

·      Ground-level ozone, which forms in the air from nitrogen oxides, carbon monoxide, methane, and other volatile organic compounds and causes almost as much warming as methane 

·      Hydrofluorocarbon (HFC) refrigerants, which are now being phased out.

How much warming is from super-pollutants?

The warming of different substances is measured in watts per square metre (W/m2). CO2 causes the most warming, 1.68 W/m2, but as shown by the diagram (left) from the US EPA report: Methane and Black carbon, impacts on the Arctic [1] methane (0.97 W/m2, including the warming of ground-level ozone formed from CH4) and black carbon (0.88 W/m2) are causing more warming than CO2.

Simple, low-cost action could slash SLCP emissions and drastically reduce the rate of warming in the critical period from now to 2050, and at the same time prevent several hundred thousand premature deaths from the air pollution that accompany methane and black carbon emissions.

  Rapidly increasing temperatures threaten to devastate our coral reefs.  The Arctic and Antarctic are warming faster than the global average rate.  When polar ice melts, it absorbs radiation instead of reflecting it back into space.  Methane is released when permafrost and undersea ice melt, and this adds to future warming.

Three experts warn "Unless we rapidly slow down these self-amplifying feedback mechanisms (by reducing super-pollutant emissions), we could lose the first major battle of climate change and face worse problems in the future" Mario Molina (Nobel prizewinner), V. Ramanathan (renowned climate scientist) and Durwood Zaelke (President, Institute for Governance & Sustainable Development).

We can help achieve this by:

·      switching from wood and gas heating to an efficient, affordable reverse cycle air conditioner (also called a heat pump)

·      opposing activities such as ‘fracking’, unnecessary burning of vegetation, including agricultural or forestry waste that produces methane and black carbon

·      lobbying governments for better monitoring of methane emissions from mines and pipelines, for program help helping developing countries replace cooking fires with clean stoves, and an effective overall strategy to avoid SLCP emissions (good examples are California's SLCP strategy and SF Bay's Spare the Air Cool the Climate

·      not letting refrigerants escape

·      composting food waste & supporting City to Soil programs

·      letting other people know the critical importance of tackling super-pollutant emissions if we want to keep the global temperature rise well below 2 degrees

·      keeping an eye on research to reduce methane emissions and improve feed efficiency of cattle and sheep

Many of us have reduced CO2 emissions by lowering use of gas and non-renewable electricity, e.g. by installing efficient appliances, insulation and rooftop solar and not leaving things on ‘standby’. Some have reduced CO2 emissions from their petrol, diesel or gas use. 

However, methane, ground-level ozone and black carbon cause as much warming as CO2.  As shown in the graph (right hand column) there’s no hope of achieving the target set at Paris by just reducing CO2 emissions.  But we can achieve the target by slashing super pollutant emissions, and so halving the rate of warming over the next 20 years, reducing the stress on our Barrier Reef and buying time to replace fossil fuel power with cheaper, renewable energy and transition to clean transport.

It is time to act now, if we want to avoid climate destabilization. 

Additional Information

The UN Environment Program and World Meteorological Organization (UNEP/WMO) formed a committee of 50 experts to investigate the best ways to protect our climate. They considered a package of measures to reduce CO
2 emissions and a package of 16 measures to reduce methane (CH4) and black carbon (BC) emissions. The projected temperatures (above) show there’s no hope of achieving the Paris target by just reducing CO2 emissions (red line). However, by also reducing BC and CH4 emissions, global temperatures are about half a degree cooler in 2040, allowing time to complete the transition to renewable energy and transport.

Renewable energy is now much cheaper than fossil fuel electricity.  Large-scale solar is being built in Queensland for less than $70/MWh
much less than the average wholesale price of coal-fired power.  The 530 MW Stockyard Hill wind farm in Victoria will generate power for just $55/MWh. The transition to cheap renewable energy now seems inevitable, but we need time to build new solar and wind farms together with battery, pumped hydro or molten salt storage.  

Melting Siberian Permafrost is producing methane blow-holes
Methane and black carbon rapidly disappear from the atmosphere if we stop emitting them, dramatically reducing the rate of current warming and so preventing future warming.   Rapidly increasing temperatures threaten to devastate our coral reefs.  The Arctic and Antarctic at are warming twice the global average rate.  When polar ice melts, it absorbs radiation instead of reflecting it back into space.  Methane is released when permafrost and undersea ice melt, and this adds to future warming. 

Prof Carlos Duarte, Director of the University of WA’s Oceans Institute also warned about the devastating consequences if current warming causes substantial quantities of methane to be released from the Arctic: “The amount of greenhouse gas stored in methane hydrates in the Arctic is several times the total CO₂ release since the industrial revolution”. 


As well as being our only hope of keeping the global temperature rise well below 2 degrees, the package of 16 measures, which includes preventing methane leaks from mines and pipelines, banning the open burning of agricultural and forestry waste, clean cookstoves in developing countries, clean diesels, and phasing out domestic log-burning heater will improve our health and prevent several hundred thousand premature deaths from air pollution.

Many people are confused about the term “carbon pollution”. Please help spread the word that the best and most cost-effective way to keep the global temperature rise well below 2 degrees is a two-pronged strategy implementing the UNEP/WMO package of 16 measures to reduce CH4 + BC while at the same time doing all we can to replace fossil fuels with renewables.

See also: Inside Climate News: These Climate Pollutants Don't Last Long, But They’re Wreaking Havoc on the Arctic. If we can cut back on methane, black carbon and other short-lived climate pollutants, it could buy time to solve the trickier problem of CO2.  By Sabrina Shankman, MAR 19, 2018
Comments