Dangerous levels of climate change for agricultural production in China

There are increasing attempts to define the measures of 'dangerous anthropogenic inference with the climate system' in context of Article 2 of the Framework Convention on Climate Change, due to its linkage to goals for stabilizing greenhouse gas concentrations. The criteria for identifying dangerous anthropogenic interference may be characterized in terms of the consequences of climate change. In this study, we use the water stress index (WSI) and agricultural net primary production (NPP) as indictors to assess where and when there might be dangerous effects arising from the projected climate changes for Chinese agricultural production. The results showed that based on HadCM3-based climate change scenarios, the region between the North China Plain and Northeast China Plain (34.25-47.75 degrees N, 110.25-126.25 degrees E) would be vulnerable to the projected climate change. The analyses on inter-annual variability showed that the agricultural water resources conditions would fluctuate through the period of 2001-2080 in the region under IPCC SRES A2 scenario, with the period of 2021-2040 as critical drought period. Agricultural NPP is projected to have a general increasing trend through the period of 2001-2080; however, it could decrease during the period of 2005-2035 in the region under the IPCC SRES A2 scenario, and during the period of 2025-2035 under IPCC SRES B2 scenario. Generally, while projected climate change could bring some potentially improved conditions for Chinese agriculture, it could also bring some critical adverse changes in water resources, which would affect the overall outcome. At this stage, while we have identified certain risks and established the general shape of the damage curve expressed as a function of global mean temperature increase, more works are needed to identify specific changes which could be dangerous for food security in China. Therefore, there is a need for the development of more integrated assessment models, which include social-economic, agricultural production and food trade modules, to help identify thresholds for impacts in further studies.