Climate-change impacts and adaptation for Pakistan’s irrigated agriculture

<p>Pakistan is one of the most vulnerable counties in terms climate-change impacts on its agricultural productivity. Agriculture is not only the largest sector in Pakistan&#8217;s economy, the food security of its over 220 million inhabitants also strongly depends on its production. As Pakistan&#8217;s arid croplands are extensively irrigated, agricultural productivity is affected by increasing temperatures (projected to increase up to 6&#176;C between 2000 and 2100 under a limited climate-change mitigation scenario), changes in water availability (i.e. river streamflow and groundwater resources) and atmospheric carbon dioxide concentrations ([CO₂]; affecting both crop productivity and water use efficiency).</p><p>Here we present the impacts of climate change on Pakistan&#8217;s primary cereal crops: wheat and rice. Impacts are quantified by combining several climate-change scenarios with a process-based coupled hydrological-crop model, VIC-WOFOST. VIC-WOFOST comprehensively estimates changes in crop growth, water resources and their interactions under climate change. Moreover, the role of elevated [CO₂] on agricultural productivity and sustainable water use is specifically assessed. We then explore the possibilities and limitations of agricultural adaptation to enable sustainable food security for Pakistan under various climate-change and population growth scenarios.</p><p>Our results show that climate-change will severely affect Pakistan&#8217;s agriculture, especially due increased temperatures and crop heat stress. However, climate-change adaptation can potentially mitigate some of these effects, especially for wheat production. Moreover, with sufficient agricultural adaptation, climate-change can even be beneficial for Pakistan&#8217;s agriculture due to the benefits of elevated [CO₂]. While our study is focussed on &#160;Pakistan, it indicates pathways for sustainable food production under climate change that may also be important for other regions that strongly depend on irrigated agriculture.</p>