学进去

Campaigners have been promoting the idea of purchasing local food recently, with the argument that it can reduce “food miles,” referring to the distance food travels from the producer to the shop owner. The greater the food miles, the higher the carbon emissions. Therefore, buying local food results in a lower carbon footprint and is considered more environmentally friendly.

Nonetheless, the actual situation is more complex than it appears. Importantly, imported food often possesses a lower carbon footprint compared to locally grown alternatives. Consider apples, for instance. Local apples in Britain, bought during winter or spring, have usually been stored in refrigeration for months, consuming substantial energy. In contrast, importing apples from New Zealand during their natural season, in spring, is more energy-efficient. Similarly, producing tomatoes in heated greenhouses in the UK has a greater environmental impact than importing them from Spain, where the climate favors their growth.

Additionally, the mode of transportation plays a significant role. Food transported by air tends to generate higher emissions. However, only a limited selection of items are flown to consumer countries, usually high-value and perishable goods that cannot be locally produced. Even in these cases, the carbon footprint of these foods may not surpass that of locally grown alternatives. For example, beans flown in from Kenya are cultivated in sunny fields using natural fertilizers, in contrast to Britain’s reliance on oil-based fertilizers and machinery.

It is crucial to acknowledge that a product’s journey extends beyond the supermarket. Driving long distances to shop for food can offset any environmental benefits gained from buying locally grown produce. Moreover, opting for local over imported food can negatively impact people in developing countries who rely on selling their produce overseas for their livelihoods.

Some supermarkets have recently attempted to raise awareness about food miles by labeling products to indicate air transportation. However, this message oversimplifies a food’s carbon footprint, which is influenced by various factors. Even if we exclusively purchase locally grown, in-season food, ethical concerns remain, potentially limiting dietary choices and affecting us all.