Bajaj Kushank, Mehrabi Zia, Kastner Thomas, Jägermeyr Jonas, Müller Christoph, Schwarzmüller Florian, Hertel Thomas W, Ramankutty Navin
Institute for Resources, Environment and Sustainability, University of British Columbia, Vancouver, British Columbia, Canada.
School of Public Policy and Global Affairs, University of British Columbia, Vancouver, British Columbia, Canada.
PLoS One. 2025 Jan 3;20(1):e0314722. doi: 10.1371/journal.pone.0314722. eCollection 2025.
The risk of national food supply disruptions is linked to both domestic production and food imports. But assessments of climate change risks for food systems typically focus on the impacts on domestic production, ignoring climate impacts in supplying regions. Here, we use global crop modeling data in combination with current trade flows to evaluate potential climate change impacts on national food supply, comparing impacts on domestic production alone (domestic production impacts) to impacts considering how climate change impacts production in all source regions (consumption impact). Under 2°C additional global mean warming over present day, our analysis highlights that climate impacts on national supply are aggravated for 53% high income and 56% upper medium income countries and mitigated for 60% low- and 71% low-medium income countries under consumption-based impacts compared to domestic impacts alone. We find that many countries are reliant on a few mega-exporters who mediate these climate impacts. Managing the risk of climate change for national food security requires a global perspective, considering not only how national production is affected, but also how climate change affects trading partners.
国家粮食供应中断的风险与国内生产和粮食进口都有关联。但对粮食系统气候变化风险的评估通常侧重于对国内生产的影响，而忽略了供应地区的气候影响。在此，我们结合全球作物模型数据和当前贸易流，评估气候变化对国家粮食供应的潜在影响，将仅对国内生产的影响（国内生产影响）与考虑气候变化如何影响所有来源地区生产的影响（消费影响）进行比较。在全球平均气温比当前升高2°C的情况下，我们的分析突出显示，与仅考虑国内影响相比，在基于消费的影响下，53%的高收入国家和56%的中高收入国家的气候对国家供应的影响加剧，而60%的低收入国家和71%的低中收入国家的影响得到缓解。我们发现，许多国家依赖少数几个大型出口国来调节这些气候影响。为保障国家粮食安全应对气候变化风险，需要全球视角，不仅要考虑国家生产如何受到影响，还要考虑气候变化如何影响贸易伙伴。
