Further memorandum submitted by Professor
Reduced moisture combined with heat
stress will probably reduce world-wide the yield of major food
staples (wheat, rice, maize) by 5 to 10 per cent by 2050 under
current best-estimate projections of climate change.
The greatest reductions are expected
to be in Africa (mainly the sub-humid parts, i.e. all but
equatorial Africa), the Middle East, and the Indian subcontinent.
The knock-on effect of this would
be by 2050 to reduce global food production by perhaps 5 to
10 per cent from levels it otherwise would have been, and
to increase food prices by more than 15 per cent3.
Price increases will leave low income
groups less able to afford sufficient food, and hunger is estimated
to increase, probably by about 50 million at risk of hunger
by 2050 (above the number estimated to occur without climate
The projected increase in hunger
due to climate change is almost entirely in Africa, due
to relatively high levels of vulnerability stemming from poverty
and weak infrastructure.
The poorest groups within the poorest
countries are those most likely to be negatively affected, due
to low levels of technology and being marginalised from sources
of information and ability.
Mitigation through emissions reduction
will delay and reduce but not avoid the problem (see accompanying
memorandum on Millions at Risk).
Impacts are almost certainly inevitable and adaptation will
Reducing poverty and empowering the
more vulnerable would generally increase resilience to climate
change. Without concerted action on this, the difference in
ability between groups and countries to adapt autonomously to
climate will increase the current difference between rich and
poor. Poorer groups will be most adversely affected, while
more wealthy ones less so.
Transfer of knowledge from
developed to developing countries, specifically about technologies
designed to respond to climate change, would increase the latter's
ability to adapt.
Specific adaptive actions to increase
resilience of agriculture to climate include: development of drought-resistant
crop varieties, use of more efficient forms of irrigation
(eg drip-feed rather than overhead), and effective pricing
of water. Most technologies exist now; the issue is implementation
rather than research.
But there are also key research efforts
needed, such as in plant breeding for climate change. A global
effort is required to develop forms of agriculture better suited
to a warmer world; one where droughts and floods may be more common.
Only the public sector will take the necessary long-term view.
Most agricultural research is now in the private sector, where
climate change is seen as too long-term to deserve attention.
The public- and foundation-funded CGIAR
should take a lead here. These activities should be supported
The policies of response to climate
change most likely to succeed are those which are integrated
into a strategy for sustainable development (see accompanying
memorandum on Millions at Risk).
Professor Martin Parry,
Jackson Environment Institute,
School of Environmental Sciences, University of
3 M Parry and M Livermore (ed) "A New assessment
of the Global Effects of Climate Change", Global Environmental
Change, Vol. 9 Special issue, 2000.; also reported in IPCC
Climate Change 2001: Synthesis Report, Geneva 2002. Back
Ev 39. Back
Consultative Group on International Agricultural Research. Back