The world’s nations are doing more to fight climate change, but the actual impact is no different.  Specifically, in 2007, about 45 percent of global greenhouse gas (GHG) emissions were subject to national legislation or strategies.  That percentage increased to 67 percent by 2012.  “However, there has not yet been a substantial deviation in global emissions from the past trend,” states the United Nations’ Intergovernmental Panel on Climate Change (IPCC) in its latest Assessment Report (AR5).  

That unpromising statement is alleviated somewhat by the finding that plans and strategies in many countries are in the early stages of development, adds the IPCC. 

But one does not have to look far in the report to lose confidence that the world’s government, businesses, and citizens will ever assemble the means and the will to keep GHGs at an atmospheric concentration level of about 450 ppm CO2 equivalent for the remainder of this century.  According to the United Nations Framework Convention on Climate Change, that concentration will likely keep the average global temperature rise below 2o Celsius (C) compared to pre-industrial levels.  Any further increase will lead to disastrous consequences, although many observers believe a 2oC increase does not have to be reached for climate-related catastrophes to occur. 

CO2 removal also

IPCC’s ARs come in three parts, with each part produced by a separate working group (WG) that focuses on different aspects of climate change.  The latest part produced by WG III assessed mitigation options.  Mitigation will need to be extraordinary, at least when compared to what is happening today, to meet the 2oC goal.  The WG III estimates that worldwide GHG emissions will need to be lowered by 40 percent to 70 percent by 2050 compared to 2010 levels and to near-zero by the end of the century.  This will probably require both reduction in emissions and removal of CO2 from the atmosphere, primarily through such land use changes as aggressive afforestation. 

Energy emissions may triple

Using baseline and mitigation scenarios, the WG III AR5 examined mitigation in energy supply; energy end-use sectors (transport, buildings, industry); agriculture, forestry, and other land use; and human settlements, infrastructure, and spatial planning.  Here are several key findings:

• Direct CO2 emissions from the energy supply may triple by 2050 compared to 2010 unless energy-intensity improvements can be significantly accelerated beyond the historical development.
• Renewable energy (RE) accounted for just over half of the new electricity-generating capacity added globally in 2012, led by growth in wind, hydro, and solar power. However, many RE technologies still need direct and/or indirect support if their market shares are to be significantly increased.
• The transport sector accounted for 27 percent of final energy use and 6.7 gigatonne CO2-equivalent (GtCO2eq) direct emissions in 2010, with baseline CO2 emissions projected to approximately double by 2050. 
• Technical and behavioral mitigation measures for all transport modes, plus new infrastructure and urban redevelopment investments, could reduce final energy demand in 2050 by around        40 percent below the baseline.  
• In 2010, the building sector accounted for around 32 percent of final energy use and 8.8 GtCO2 emissions, including direct and indirect emissions, with energy demand projected to approximately double and CO2 emissions to increase by 50 percent to 150 percent by midcentury in baseline scenarios.
• For new buildings, the adoption of very-low-energy building codes has progressed substantially since AR4.  Retrofits form a key part of the mitigation strategy in countries with established building stocks, and reductions of heating/cooling energy use by 50 percent to 90 percent in individual buildings have been achieved.
• In 2010, industry accounted for around 28 percent of final energy use, and 13 GtCO2 emissions, including direct and indirect emissions as well as process emissions, with emissions projected to increase by 50 percent to 150 percent by 2050 in the baseline scenarios unless energy-efficiency improvements are accelerated significantly.
• Improvements in GHG emissions efficiency and in the efficiency of material use, recycling and reuse of materials and products, and overall reductions in product demand (e.g., through a more-intensive use of products) and service demand could, in addition to energy efficiency, help reduce GHG emissions below the baseline level in the industry sector. 

WG III AR5