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Promoting low carbon transPort in india
Low Carbon City:
A Guidebook for City Planners and Practitioners
3.2 Global targets
The current concentration of CO
2
in the atmosphere stands at 400 ppmv, and is continuing to rise. In
order to remain within the global 2°C temperature target, the greenhouse gas concentration will need to
stabilise at approximately 450 ppm CO
2
e (Table 2). The stabilisation target could be achieved by following
alternate emission pathways. A recent assessment (UNEP, 2012) shows that scenarios that meet the 2°C
limit have global emissions in 2050 roughly 40% below 1990 emission levels and roughly 60% below 2010
emission levels. The medium range (50–66%) of probability of staying below the 2°C limit requires global
emissions to peak before 2020 (Figure 3). One of the suggested pathways shows that emissions need to
peak around 2020, and decline progressively to reach the target emissions reduction by 2050.
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