The world is producing enough food, however today almost one billion people are starving while another billion is malnourished as articulated in FAO reports1. The shortage of food and malnutrition was due to food lost, e.g. the after-harvest loss problem as articulated by Chiou published in Issue 3 of the Asia-Pacific Perspective, 2012, and unstable economical and physical accessibility of food for one sixth populations in the globe.
Food security and climate change are two factors become interdependent and present new challenges to modern agriculture. On the one hand, agricultural practices should increase food production in quantity, quality as well as diversity to meet rapidly rising demand of humans on the planet. According to the FAO reports, food production needs to increase by 60% for 2050 compared to today . The increase of food will mainly come from developing countries where agricultural technology and production is comparatively low and at the same time facing the demand of food growing in an accelerating pace.
The trend of climate change and its consequence, on the other hand, present emerging, severe challenges to current development of agriculture. There are two sides of the relation between agriculture and climate change. Agriculture is an important contributor to climate change and meanwhile greatly influenced by the latter. Agriculture is consuming natural resources heavily in many aspects. It is one of primary sources of greenhouse gases , including nitrous oxide (N2O) and methane (CH4); accounts for 70% of water withdrawal, and is one significant activity responsible for deforestation, forest degradation and loss of biodiversity. In EU, the food system accounts for 31% of the greenhouse emission. IPCC  estimates that by 2030, nitrous oxide will increase by 35-60% while methane by 60%. It is not difficult to see the desire burning for new ways of agriculture considering that huge additional portion of food production is needed to feed our future generations but constrained by the inefficiency of natural resources of current agricultural activities.
Agriculture is, at the same time, significantly impacted by climate change. According to Climate Trends and Global Crop Production Since 1980 by Lobell et al. , global average temperatures have risen by 0.13ºC since 1950. At the global level, maize and wheat showed negative impacts and suffered net loss of 3.8% and 5.5% respectively in relation to the criteria without the climate trends in 1980-2008. Nevertheless, the magnitude of food reduction varies between countries, e.g. Russia had 15% loss of wheat while US had little effect due to the weak trend of climate change.
Another feature of the impact of climate change on agriculture is that temperature is a more significant driver of food reduction than precipitation and for the past decades the change in temperature was larger than precipitation. This implies agriculture in low latitude regions can be more fragile than in high latitude, and thus food security will be greatly undermined in tropical and subtropical areas where economically vulnerable countries locate. Gap between developing and developed countries as a result is widening and conflicts become more possible when the situation is getting worse. Lobell et al. (2010) illustrate a different story happening in high latitude where rice production may be benefitted from warming. This observation is consistent with the IPCC report (2007)  which also illustrates that global warming may increase productivity of both crop and livestock in mid to high latitudes. For instance, the need of irrigation is increasing in Greenland and even in some areas where permanent irrigation system can be found today due to longer growing season on terrestrial vegetation.
Modern technology is another factor transforming agriculture to be more sensitive to climate change. As shown in Schlenker and Lobell's  survey on maize, sorghum, millet, groundnut and cassava in Sub-Saharan Africa that high fertilizer rate which increased yield also strengthens crop sensitivity to weather. In other words, climate change has more impact on highly fertilized crop. Similarly, a study conducted by the World Bank  illustrate that irrigated crop are expected to continue to increase despite the challenge of climate change, however merely up to 2030, by then their yield will drop rather quickly.
Numerous existing evidences show that mitigating climate change and ensuring food security are not incompatible but in fact imperative to each other. Developing agricultural activities of resource efficiency and climate friendly (or climate-smart) is not only achievable but one of primary method to feed our future. The main objective of such win-win evolvement is to transform both agricultural activities and food systems to be (resource and land) efficient and resilient at both community and global levels.
There are at least 3 tasks governments have to address. First is to assist pastoralists by introducing innovative ways to improve resource efficiency and increase crop yield. For instance, the Urea Deep Placement technique is a good climate-smart solution to reduce the use of fertilizer and increase yield of rice by just placing urea deep in the soil and close to the roots of the paddy. Second is to establish overarching policy framework to transform agriculture to be efficient and resilient, and concert the food system management with the climate regime at the national and global spheres. This includes reduce subsidies on variety of agricultural practices, e.g. fertilizer, and provide incentives to climate mitigation actions, e.g. reduce deforestation, or even further linked to green economy/growth strategies. The last but surely not the least is to manage agricultural activities under the overarching framework of food systems and ecosystems as a whole. In considering agriculture's impact on climate change, discovering its mitigation potentials and evaluating possible methods, policy makers should view in a wider perspective and make decision/planning in a holistic manner. In so doing, governments could create favorable policy environment in various spheres to increase yield of crop, decouple agricultural production from greenhouse gas emission and contribute to food security as well as mitigation of climate change simultaneously.
1 For instance, FAO (2012), Greening the Economy with Climate-Smart Agriculture, Hanoi, Vietnam, 3-7 Sep, FAO.
2 Agriculture is not a significant source directly responsible for carbon dioxide emission. However, agriculture imposes negative effects on carbon dioxide density in indirect ways, e.g. deforestation reduces the sinks capacity of original vegetation.
3 Metz, B, Davidson, O., Bosch, P., Dave, R. and L., Meyer (Eds), Glossary, Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the IPCC, Cambridge University Press, Cambridge.
4 Lobell, D., Schlenker, W. and Costa-Robers, J. (2011), Science.
5 Parry, M., Canziani, O., Palutikof, J., van der Linder, P. and C.E. Hanson (Eds), Glossary, Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Glossary, Cambridge University Press, Cambridge, pp.869-883.
6 (2010)Environ. Res. Lett. 5 014010
7 Gommes, R., Hairech, T., Rosillon, D., Balaghi, R., and H., Kanamaru (2009), Morocco Study on the Impact of Climate Change on the Agricultural Sector, 20091007.