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Short-Lived Climate Pollutants (SLCP) causing Arctic temperatures to soar
Havoc is being wreaked on the Arctic by short-lived climate pollutants (SLCP), see 'Inside Climate Science' (ICS, 19 March 2018) [1]. The combined effect of methane and black carbon is an estimated 1 °C increase in Arctic temperatures [1].

Reductions in CO2 emissions will take decades to significantly reduce global temperatures but: "Tackling the problems raised by these potent pollutants—methane (CH4), black carbon (BC), tropospheric ozone (O3) and hydrofluorocarbons (HFCs) ... offers a glimmer of opportunity for saving the rapidly warming Arctic. If they can be significantly reduced, the impact will be felt almost immediately, giving countries much needed time to solve the trickier problem of CO2."  [1].

A 2016 US EPA Report 'Methane and Black Carbon Impacts on the Arctic: Communicating the Science' [2] came to the same conclusion.  It shows a graph of forcings - CO2: 1.68 W/m2, CH4: 0.99 and black carbon: 0.88. These values for the effect of man-made emissions presumably include the effect of increased tropospheric O3 (abundance-based forcing of 0.37 W/m2 [3]) and stratospheric water vapour associated with CH4 emissions. Thus the combined effect of CH4, BC, CO, HFC and CO emissions is greater than CO2.  

Research published in 2016 [4] co-authored by G. Myhre, a coordinating lead author of chapter 8 of the IPCC 5th Assessment Report, suggests the true effect is even worse with an estimated 25% increase in methane's forcing to 0.61 W/m2

A lay summary of the above and previous UN Environment Program research showing there's little chance of keeping the global temperature rise well below 2 degrees, unless we reduce current warming by tackling SLCP as well CO2 emissions [5] is available on the web [6]. Sharply reducing current warming by tackling SLCP is also the best, and perhaps the only, way to save our coral reefs.  As a result of current warming, two thirds of the great barrier reef has been hit by back-to-back mass coral bleaching with 70% of shallow water corals dead north of Port Douglas.

Feedback mechanism: rising temperatures melt ice, release methane & create even more warming
The ICS report warns about worrisome feedback: "At the same time, warming in the Arctic is leading to a worrisome feedback loop. As temperatures rise, permafrost thaws, unleashing trapped methane into the atmosphere and leading to more warming. Scientists are working to figure out just how much methane is in the permafrost—suffice it to say, it's a lot" [1].  Methane blow-holes are one example of what can happen [4] .  Increasing Arctic temperatures are also melting sub-sea ice. According to Prof Carlos Duarte, Director of the University of WA’s Oceans Institute: “The amount of greenhouse gas stored in methane hydrates in the Arctic is several times the total CO₂ release since the industrial revolution”. 

Renewables cheaper than coal - transition inevitable, but needs time
Renewable energy has a very promising outlook - wind and solar are already cheaper than new coal-fired power. The same will soon be true for solar thermal, batteries and pumped hydro storage, as well as electric vehicles. The switch to renewable energy is inevitable (despite the ignorance of our COALition government), but it will take time. 

A major problem is that we might not have enough time for the transition, because current warming increases future warming. Three experts warned "Unless we rapidly slow down these self-amplifying feedback mechanisms, 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).

Effective, affordable ways to immediately slow global temperature rise & save lives
A UN Environment Program report [5] investigated the most cost-effective ways to slow current warming by reducing CH4 and BC emissions in developed and developing countries.  Unless we implement these measures, we'll exceed 1.5 degrees of warming by about 2030, and there's little chance of keeping the global temperature rise below 2 degrees.  By contrast, in addition to a good chance of meeting the global temperature target,  "Full implementation of the identified measures could avoid 2.4 million premature deaths (within a range of 0.7–4.6 million) and the loss of 52 million tonnes (within a range of 30–140 million tonnes), 1–4 per cent, of the global production of maize, rice, soybean and wheat each year" [5]

The Climate Council's factsheet 'Climate Change & Soaring Arctic Winter Temperatures' notes the worrisome feedback from melting sea ice: "more open water, which absorbs solar radiation rather than reflecting it as ice does. This is a vicious circle (called a ‘feedback loop’ by scientists); as temperatures warm and more sea ice melts, it causes temperatures to warm even more and the cycle continues ... Extreme weather events and other climate impacts (e.g. Arctic warming) will only get worse unless we rapidly and deeply reduce our greenhouse gas emissions. The next few years – the last quarter of the Critical Decade – will be decisive to get emissions tracking strongly downwards."  

However, the factsheet does not mention the benefits of rapid reductions in warming by reducing SLCP.  

Has the Climate Council considered what Australia could to to reduce SLCP, e.g.
    1) Provide accurate emissions inventories using the latest data - the 2016 research suggests a 100-year GWP of 42 for methane, so our current inventory assuming that CH4 is only 25 times as potent as CO2 significantly under-estimates the true climate impact. International agreement on updating official methodologies takes time, but our policies should be guided by the true impact on the climate, not out-of-date data.
    2) Provide estimates of the climate impact over 20, as well as 100 years, for all substances, including CO and BC emissions, that are not covered by current agreed methodologies. Short-term impacts are extremely important for sensitive ecosystems such as coral reefs - we can't save them unless we reduce the current stress that caused the back-to-back bleaching events.  
    3) Obtain accurate estimates of methane leaks from mines, pipelines and fracking.
    4) Lobby for overseas aid programs to install clean cook-stoves in developing countries
    5) Check whether refrigerants are disposed of properly, and that atmospheric leakage is minimal
    6) A CSIRO study measured CH4, BC, CO and CO2 emissions from modern Australian wood stoves.  Results show that the average wood stove in Sydney (which burns 2 tonnes of firewood a year) will cause as much global warming over the next 20 years as 50 homes heated by efficient air conditioners running off standard coal-fired power, or many more homes that use green power, or have rooftop PV.  Emissions from burning the estimated 6 million tonnes of firewood in Australia every year will cause as almost as much global warming over the next 20 years as the CO2 emitted by Australia's entire road transport fleet.  Despite less than 5% of Sydney households using wood as the main form of heating, chemical fingerprinting of Sydney's air pollution shows that residential wood heating is the largest single source of pollution-related deaths - approximately 100 premature every year, compared to about 40 from power station pollution and 17 from shipping pollution. The irony is that many Australians think that wood heating benefits the climate, and have no idea that the chief medical officer of NSW considers wood heating so detrimental to health she supports banning and phasing them out in built-up urban areas

Optimal strategy
It would be really interesting to know your view of the optimal strategy, including whether 1 to 6 above will help tackle SLCP emissions, reduce current warming, help protect our reef and slow the worrisome feedback if current warming melts glaciers and polar ice and releases methane from undersea ice and permafrost.

References 
3. Improved Attribution of Climate Forcing to Emissions. Drew T. Shindell, et al. Science 326, 716 (2009); DOI: 10.1126/science.1174760 
4. Radiative forcing of carbon dioxide, methane, and nitrous oxide: A significant revision of the methane radiative forcing. doi: 10.1002/2016GL071930 
5. Integrated Assessment of Black Carbon and Tropospheric Ozone. Summary for Decision Makers.  UN Environment Program & World Meteorological Organization. www.unenvironment.org/resources/report/integrated-assessment-black-carbon-and-tropospheric-ozone-summary-decision-makers  
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