Kushank Bajaj

Fruit and vegetable supply is essential for a healthy diet, yet the exposure of supply chains to climate-related conditions is often overlooked, particularly when sourcing crosses national borders. We develop provincial-scale food flows for 18 fruits and 16 vegetables using average 2018–2022 production and trade data, including estimated interprovincial flows and derived products. We then link these recent sourcing patterns to changes in maximum five-day rainfall, consecutive dry days, days below 0 °C, and days above 35 °C from +1 °C to +3 °C global mean warming relative to 1850–1899. Across Canada’s supply, 43 % of fruit and 19 % of vegetables are sourced from regions projected to experience at least 15 additional days above 35 °C, 19 % and 8 % from regions with at least five additional consecutive dry days, 31 % and 9 % from regions with at least a 5 % decrease in maximum five-day rainfall, and 7 % and 2 % from regions with at least 10 fewer days below 0 °C, respectively. Exposure is concentrated in specific supply chains, including lettuce sourced from California and Arizona and avocados from Mexico, and varies across provinces because of differences in sourcing portfolios. This exposure assessment holds recent sourcing patterns constant and does not estimate crop-yield losses, future trade adjustments, prices, or supply disruptions. It provides a basis for identifying the most exposed commodity, province, and source regions that may warrant more detailed impact and adaptation assessment.

Previous estimates of food transport emissions vary widely, fueling debate about their contribution to agrifood emissions. Using food supply data and multimodal transport networks, we estimate global food transport emissions at ~0.82 GtCO2 annually (2019-2023), lower than previous food-miles-based estimates and consistent with national greenhouse gas inventories. Emissions are concentrated in domestic transport and a few countries and commodities, highlighting where targeted mitigation efforts could most effectively reduce food transport emissions.

As climate change intensifies, extreme weather is becoming a major threat to global food security. Yet we still lack a good understanding of how these extremes will be distributed across the world’s agricultural lands—particularly across small versus large croplands and pasturelands. In this study, we assess their exposure to extreme weather in a warming world. In a world that is 2 °C warmer than today, 25% (11 million km ² ) of present-day agricultural lands will face over two months of extreme heat, up from 16% today (7 million km ² ), and another ∼2% (5 million km ² ) will be exposed to a combination of two or more extremes, up from 10% (4 million km ² ). The total area exposed to prolonged dry conditions and extreme precipitation will remain unchanged (less than 1% or 5 million km ² , with increases in some regions balanced by decreases elsewhere), while ∼2% less area (2 million km ² ), down from 7% (3 million km ² ), will experience a month of frost. Future exposure to extreme weather varies by land use type. Pasturelands will experience prolonged exposure to heat stress, whereas croplands will be exposed to higher excessive rains and heat stress combined. Spatial correlations between farm size and geography indicate potential differences in exposure. Exposure to extreme precipitation and heat stress is highest in small (1–2 ha) and medium (2–4 ha) cropland and pastureland, respectively. These findings offer a preliminary global assessment of how exposure to extreme weather varies by farm size and land use, underscoring the need for tailored adaptation strategies to safeguard food security in a warming world.

The global agrifood system is central to many challenges humanity faces today. Despite significant growth in total production, it fails to ensure food security for all, drives biodiversity decline, and majorly contributes to climate change. Research on agrifood-system burdens often focusses on the national level and isolated burdens, ignoring their systemic complexity. We address this knowledge gap by combining global subnational datasets proxying four key dimensions of agrifood-system burdens: environmental footprint, climate change, income poverty, and malnutrition. We map global hotspots of co-occurring agrifood-system burdens for 2017. We overlay these with data on ambient population counts, agricultural areas, farm size distributions, and lands inhabited by Indigenous peoples to identify spatial correspondence between people in vulnerable contexts and food production regions facing these burdens. We further assess countries’ relative burden against their inequality and governance indicators. Burden hotspots occupy many regions worldwide, especially in low-income, (sub)tropical regions. Single burdens occupy regions harbouring about 5 billion people (∼66% of the global population) and 1.8 billion ha of agricultural lands (∼40%), while multiple burdens occupy regions with about 1.9 billion people and 470 million ha agricultural lands. Environmental footprint is the strongest contributor to these burden profiles. Regions with traditionally marginalised communities (i.e. small-scale farmers and Indigenous peoples) disproportionally face multiple burdens. Agrifood-system burdens are more prevalent in countries with higher economic inequality and poorer governance. Burden profiles vary substantially within and between countries, necessitating regionalised and context-specific policies for effective, bundled, and targeted solutions. Addressing agrifood-system burdens can also synergise with tackling other current global challenges, like biodiversity loss and environmental justice.

As climate change intensifies, extreme weather is becoming a major threat to global food security. Yet we still lack a good understanding of how these extremes will be distributed across the world’s agricultural lands—particularly across small versus large crop and pasturelands. In this study, we assess the exposure of global agricultural lands to extreme weather in a warming world, focusing on small and large crop and pasturelands. In a world that is 2°C warmer than today, 25% (11 million hectares, Mha) of present-day agricultural lands will face over two months of extreme heat, up from 16% today (7 Mha), and another ~2% (5 Mha) will be exposed to a combination of two or more extremes, up from 10% (4 Mha). The total area exposed to prolonged dry conditions and extreme precipitation will remain unchanged (less than 1% or 5 Mha, with increases in some regions balanced by decreases elsewhere), while ~2% less area (2 Mha), down from 7% (3 Mha), will experience a month of frost. Future exposure to extreme weather varies by land use type. Pasture lands will experience prolonged exposure to heat stress, whereas croplands will be exposed to higher excessive rains and heat stress combined. Spatial correlations between farm size and geography indicate potential differences in exposure. Exposure to extreme precipitation and heat stress is highest in small (1-2 ha) and medium (2-4 ha) crop and pastureland, respectively. These findings offer a preliminary global assessment of how exposure to extreme weather varies by farm size and land use, underscoring the need for tailored adaptation strategies to safeguard food security in a warming world.

Fruit and vegetable supply is essential for a healthy diet, yet their vulnerability to climate risks is often overlooked, particularly in terms of cross-border risks. In this study, we assess the exposure of Canada's fruit and vegetable supply to future weather extremes. To do so, we first develop provincial scale food flows for 18 fruits and 16 vegetables from 2018 to 2022, resolving for interprovincial and international trade. Integrating this novel dataset with up-to-date global climate simulations, we assess Canada's consumption-based and cross-border future exposure to excessive rain, dry spells, cold snaps, and heat stress, both by produce and province. Our findings reveal the most exposed sourcing regions for different produce and weather extremes, emphasizing how climate risks cross borders. We underscore the need for comprehensive approaches to evaluate climate risks and develop resilience strategies in Canada's fruit and vegetable supply chain to ensure nutritional security.

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.