Went to a talk on March 19, 2012 by Dr Joel Schwarz about a recent UNEP report on Short Lived Climate Forcers:
Integrated Assessment of Black carbon and Tropospheric Ozone and Near Term Climate Protection and Clean Air Benefits
http://www.unep.org/dewa/Porta…
Summary for Decision Makers
http://www.unep.org/pdf/Near_T…
The report focuses on three SCLF [short lived climate forcers] – black carbon, tropospheric ozone and methane [an ozone precursor*] – because reducing them will provide significant benefits through improved air quality and a slowing of near-term climate change.
Black carbon and tropospheric (10 – 20 km above ground) ozone are resident in the atmosphere for a few days to three weeks (3-8 days for carbon, up to 4-18 days for ozone). Methane has an atmospheric lifetime of 12 years, ± 3 years.
“Full implementation” of all the identified measures could reduce future global warming by “0.5˚C (within a range of 0.2-0.7˚C)”. If implemented by 2030, this tactic might halve the potential increase in global temperature projected for 2050. “The rate of regional temperature increase would also be reduced” wherever they are put into practice.
These 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.” Benefits will be felt immediately “in or close to the regions” where black carbon, methane, and tropospheric ozone are reduced. The potential for emissions reductions, climate, health, and economic benefits are highest in Asia but gains can also be realized in Africa, Latin America, and wherever these measures are put into practice.
A few emission reduction measures “targeting black carbon and ozone precursors could immediately begin to protect climate, public health, water and food security, and ecosystems. Measures include the recovery of methane from coal, oil and gas extraction and transport, methane capture in waste management, use of clean-burning stoves for residential cooking, diesel particulate filters for vehicles and the banning of field burning of agricultural waste.”
All these benefits can be obtained with existing technology but require significant strategic investment and institutional arrangements to make them widespread, part of general and every day use.
*Ozone is not directly emitted. It is a secondary pollutant that is formed in the troposphere by sunlight-driven chemical reactions involving carbon monoxide (CO), non-methane volatile organic compounds (NMVOCs), methane (CH4), and nitrogen oxides (NO ). Ozone in the troposphere is the third most human-emitted greenhouse gas, after CO2 and methane. Ozone formation increases as temperature rises.
Continue reading Short Term Climate Forces: Black Carbon, Methane, and Tropospheric Ozone