37
Rapid implementation of 16 SLCP control
measures to reduce CH
4
and BC has the
potential to avoid the annual loss of over
50 million metric tonnes of crop yields
per year by 2030 (UNEP &WMO 2011).
Benefits are evenly split between CH
4
and
BC control measures, which similarly impact
O
3
formation. For CH
4
measures, addressing
emissions from coal mining, especially in
Asia, and from oil and gas production, would
bring the greatest benefits followed
by improved waste treatment. For BC
measures, the greatest benefits would come
from measures addressing the transport
sector. CH
4
tends to impact O
3
formation
further away from the source than BC
co-pollutants, some of which are also
O
3
precursors. Hence benefits from BC
measures are felt closer to the emission
source than those of CH
4
measures.
In terms of tonnage, the largest avoided crop
yield losses will be achieved in China, India,
and the United States, followed by Pakistan
and Brazil. In terms of percentage, the main
improvements will be gained in the Middle
East, followed by Central and South Asia.
A large impact on percentage crop yields in
Mexico, quite distinct from neighbouring
countries, reflects the influence of local
emission changes (Shindell D.
et al
. 2012).
17
Benefits for Agriculture