posts: 29743
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| 29743 | Very little of global food is transported by air; this greatly reduces the climate benefits of eating local | untitled-reusable-block-184 | wp_block | publish | <!-- wp:paragraph --> <p>People often think that eating ‘local’ – buying foods which are produced close to home – is one of the most effective ways to reduce our carbon footprint.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>This is certainly true for foods that are transported by plane. But the reality is that very little of our food is.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>Most food travels by sea, not by air</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>One simple way to compare the means of transport for food is to sum up how many kilometers planes with food freight travel; and compare this to how how many kilometers trains, and ships, and trucks do.<br><br>But this does not give the complete picture because a boat can carry much more food for a given distance than a truck can. To give an informative comparison, we use a metric called ‘food miles’; this is calculated as the distance each transport method covers multiplied by the quantity of food transported (by mass). This gives us a comparison of food miles in tonne-kilometers.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The chart here shows the share of global ‘food miles’ by transport method. This data is sourced from the work of Joseph Poore and Thomas Nemecek, published in the journal <em>Science</em> in 2018.{ref}Poore, J., & Nemecek, T. (2018). <a href="https://science.sciencemag.org/content/360/6392/987">Reducing food’s environmental impacts through producers and consumers</a>. <em>Science</em>, 360(6392), 987-992.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>As the data here shows, only 0.16% of food miles come from air travel. Most – nearly 60% – comes by boat.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>You can see this data in absolute terms, in tonne-kilometers, <a href="https://ourworldindata.org/grapher/food-miles-by-transport"><strong>here</strong></a>.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/share-food-miles-by-method" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Whether food travels by sea or air makes all the difference</h3> <!-- /wp:heading --> <!-- wp:columns --> <div class="wp-block-columns"><!-- wp:column --> <div class="wp-block-column"><!-- wp:paragraph --> <p>Transporting food by air emits around 50 times as much greenhouse gases as transporting the same amount by sea. More specifically, 0.023 kilograms of carbon dioxide-equivalents (CO<sub>2</sub>eq) per tonne-kilometer by sea, versus 1.13 kilograms CO<sub>2</sub>eq by air. We see these emission factors for different transport modes in the table.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>For food that is transported by sea, transportation doesn’t actually add much to the carbon footprint. Since most of our food is transported by sea, transport emissions only account for 6% of the carbon footprint of food, on average.{ref}You might think that this figure of 6% is strongly dependent on where in the world you live – that if you live somewhere very remote, that the role of transport must be much higher. But this is not really the case. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Let’s take the example of beef from a beef herd. The average footprint of this beef is approximately 60 kilograms of CO<sub>2</sub>eq per kilogram of beef. Let’s compare the transport footprint of buying from your local farmer (who lives just down the road from you), versus someone in the UK transporting beef from Central America (approximately 9000 kilometers away).</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Transporting food by boat emits 0.023 kilograms of CO<sub>2</sub>eq per tonne of product per kilometer. To transport the 9000 kilometers from Central America to the UK therefore emits 0.207 kilograms CO<sub>2</sub>eq [9000km * 0.023kg per tonne-kilometer / 1000 = 0.207 kg CO<sub>2</sub>eq per kg]. This is only equivalent to 0.35% of the total footprint of the 60 kilograms of CO<sub>2</sub>eq per kilogram of beef. <br><br>If you buy from your local farmer – let’s assume you walk there, and have zero transport emissions – your beef footprint is 59.8 kilograms CO<sub>2</sub>eq per kilogram [we calculate this as 60kg - 0.2kg]. It makes almost no difference.<br><br>Especially for foods with a large footprint, transport as a share of the food’s total emissions is fairly insensitive to the distance travelled.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But for those food items that travel by air, travel distance <em>does</em> have a large impact. We should avoid air-freighted goods where we can.</p> <!-- /wp:paragraph --></div> <!-- /wp:column --> <!-- wp:column --> <div class="wp-block-column"><!-- wp:paragraph --> <p><em>Emission factors for freight by transport mode (kilograms of CO<sub>2</sub>eq per tonne-kilometer)</em>{ref}These emissions factors by transport mode are those applied in the analysis by Joseph Poore and Thomas Nemecek (2018), published in <em>Science</em>. These emission factors are sourced from <a href="https://www.ecoinvent.org/database/ecoinvent-33/ecoinvent-33.html">Ecoinvent v3.3</a>, a comprehensive database which is commonly used in international life-cycle analyses (LCA). Emission factors can span a range of values depending on factors such as the efficiency of vehicle used; packing/loading density of freight; distribution between passenger and freight allocation in shared transport; amongst other factors.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><table><thead><tr><th scope="col" colSpan="1">Transport mode</th><th scope="col" colSpan="1">Ambient transport (kg CO<sub>2</sub>eq per tonne-kilometer)</th><th scope="col" colSpan="1">Temperature-controlled transport (kg CO<sub>2</sub>eq per tonne-kilometer)</th></tr></thead><tbody><tr><td colSpan="1" rowspan="1">Road Transport</td><td colSpan="1" rowspan="1">0.2</td><td colSpan="1" rowspan="1">0.2 to 0.66</td></tr><tr><td colSpan="1" rowspan="1">Rail Transport</td><td colSpan="1" rowspan="1">0.05</td><td colSpan="1" rowspan="1">0.06</td></tr><tr><td colSpan="1" rowspan="1">Sea / Inland Water Transport</td><td colSpan="1" rowspan="1">0.01</td><td colSpan="1" rowspan="1">0.02</td></tr><tr><td colSpan="1" rowspan="1">Air Transport</td><td colSpan="1" rowspan="1">1.13</td><td colSpan="1" rowspan="1">1.13</td></tr></tbody></table></p> <!-- /wp:paragraph --></div> <!-- /wp:column --></div> <!-- /wp:columns --> <!-- wp:paragraph --> <p>Which foods are air-freighted? How do we know which products to avoid?</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Foods which are air-freighted tend to be those which are highly perishable. This means they need to be eaten soon after they’ve been harvested. In this case, transport by boat is too slow, leaving air travel as the only feasible option. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Some fruit and vegetables tend to fall into this category. Asparagus, green beans and berries are common examples of air-freighted goods.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>It is often hard for consumers to identify foods that have travelled by air, since they’re rarely labeled as such. This makes them hard to avoid. A general rule is to avoid foods that have a very short shelf-life <em>and</em> have traveled a long way (many labels have the country of ‘origin’ which helps with this). This is especially true for foods where there is a strong emphasis on ‘freshness’: for these products, transport speed is a priority.</p> <!-- /wp:paragraph --> <!-- wp:owid/additional-information --> <!-- wp:heading {"level":3} --> <h3>Example: how does the footprint of vegetables change if they travel across the world by plane vs. boat?</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Let’s take the example of asparagus. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>If you live in the UK, you may have noticed on food labels that asparagus is often imported from Peru. They often come by plane. How does this affect their carbon footprint?<br><br>The average carbon footprint of asparagus is around 0.4 kilograms CO<sub>2</sub>eq per kilogram. Flying from Lima to London <a href="https://www.entfernungsrechner.net/en/distance/city/2643743/city/3936456">is around</a> 10,000 kilometers. If we were to fly one kilogram of asparagus over this distance, this would emit around 11 kilograms of CO<sub>2</sub>eq [10,000km * 1.13 kilograms CO<sub>2</sub>eq per tonne-kilometer for flying / 1000 = 11.3 kg CO<sub>2</sub>eq per kg]. Suddenly the footprint of your asparagus changes from being a low-carbon food to a relatively high-carbon one, at almost 12 kg CO<sub>2</sub>eq per kg. It has a higher carbon footprint that a kilogram of chicken or pork.<br><br>It is the fact that it’s flown, rather than the travel distance itself that gives asparagus a large footprint in this example. If it traveled the same distance by boat, the travel emissions would be only 0.26 kg CO<sub>2</sub>eq per kg [10,000km * 0.026 kilograms CO<sub>2</sub>eq per tonne-kilometer for transport by boat / 1000 = 0.26 kg CO<sub>2</sub>eq per kg]. So its total footprint would be around 0.67 kg CO<sub>2</sub>eq per kg, which still makes it a low-carbon food option.</p> <!-- /wp:paragraph --> <!-- /wp:owid/additional-information --> | {
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"text": "eq per kilogram of beef. Let\u2019s compare the transport footprint of buying from your local farmer (who lives just down the road from you), versus someone in the UK transporting beef from Central America (approximately 9000 kilometers away).",
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"text": "If you buy from your local farmer \u2013 let\u2019s assume you walk there, and have zero transport emissions \u2013 your beef footprint is 59.8 kilograms CO",
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"text": "If you live in the UK, you may have noticed on food labels that asparagus is often imported from Peru. They often come by plane. How does this affect their carbon footprint?",
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"text": "The average carbon footprint of asparagus is around 0.4 kilograms CO",
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"text": "eq per kilogram. Flying from Lima to London ",
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"text": " 10,000 kilometers. If we were to fly one kilogram of asparagus over this distance, this would emit around 11 kilograms of CO",
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"text": "eq [10,000km * 1.13 kilograms CO",
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"text": "eq per tonne-kilometer for flying / 1000 = 11.3 kg CO",
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"text": "eq per kg]. Suddenly the footprint of your asparagus changes from being a low-carbon food to a relatively high-carbon one, at almost 12 kg CO",
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"text": "eq per kg. It has a higher carbon footprint that a kilogram of chicken or pork.",
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"text": "It is the fact that it\u2019s flown, rather than the travel distance itself that gives asparagus a large footprint in this example. If it traveled the same distance by boat, the travel emissions would be only 0.26 kg CO",
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"text": "eq per kg [10,000km * 0.026 kilograms CO",
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"text": "eq per tonne-kilometer for transport by boat / 1000 = 0.26 kg CO",
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"text": "eq per kg]. So its total footprint would be around 0.67 kg CO",
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"title": "Very little of global food is transported by air; this greatly reduces the climate benefits of eating local",
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2020-01-28 10:22:43 | 2020-04-30 14:00:11 | {} |
People often think that eating ‘local’ – buying foods which are produced close to home – is one of the most effective ways to reduce our carbon footprint. This is certainly true for foods that are transported by plane. But the reality is that very little of our food is. ## Most food travels by sea, not by air One simple way to compare the means of transport for food is to sum up how many kilometers planes with food freight travel; and compare this to how how many kilometers trains, and ships, and trucks do. But this does not give the complete picture because a boat can carry much more food for a given distance than a truck can. To give an informative comparison, we use a metric called ‘food miles’; this is calculated as the distance each transport method covers multiplied by the quantity of food transported (by mass). This gives us a comparison of food miles in tonne-kilometers. The chart here shows the share of global ‘food miles’ by transport method. This data is sourced from the work of Joseph Poore and Thomas Nemecek, published in the journal _Science_ in 2018.{ref}Poore, J., & Nemecek, T. (2018). [Reducing food’s environmental impacts through producers and consumers](https://science.sciencemag.org/content/360/6392/987). _Science_, 360(6392), 987-992.{/ref} As the data here shows, only 0.16% of food miles come from air travel. Most – nearly 60% – comes by boat. You can see this data in absolute terms, in tonne-kilometers, [**here**](https://ourworldindata.org/grapher/food-miles-by-transport). <Chart url="https://ourworldindata.org/grapher/share-food-miles-by-method"/> ## Whether food travels by sea or air makes all the difference Transporting food by air emits around 50 times as much greenhouse gases as transporting the same amount by sea. More specifically, 0.023 kilograms of carbon dioxide-equivalents (CO2eq) per tonne-kilometer by sea, versus 1.13 kilograms CO2eq by air. We see these emission factors for different transport modes in the table. For food that is transported by sea, transportation doesn’t actually add much to the carbon footprint. Since most of our food is transported by sea, transport emissions only account for 6% of the carbon footprint of food, on average.{ref}You might think that this figure of 6% is strongly dependent on where in the world you live – that if you live somewhere very remote, that the role of transport must be much higher. But this is not really the case. Let’s take the example of beef from a beef herd. The average footprint of this beef is approximately 60 kilograms of CO2eq per kilogram of beef. Let’s compare the transport footprint of buying from your local farmer (who lives just down the road from you), versus someone in the UK transporting beef from Central America (approximately 9000 kilometers away). Transporting food by boat emits 0.023 kilograms of CO2eq per tonne of product per kilometer. To transport the 9000 kilometers from Central America to the UK therefore emits 0.207 kilograms CO2eq [9000km * 0.023kg per tonne-kilometer / 1000 = 0.207 kg CO2eq per kg]. This is only equivalent to 0.35% of the total footprint of the 60 kilograms of CO2eq per kilogram of beef. If you buy from your local farmer – let’s assume you walk there, and have zero transport emissions – your beef footprint is 59.8 kilograms CO2eq per kilogram [we calculate this as 60kg - 0.2kg]. It makes almost no difference. Especially for foods with a large footprint, transport as a share of the food’s total emissions is fairly insensitive to the distance travelled.{/ref} But for those food items that travel by air, travel distance _does_ have a large impact. We should avoid air-freighted goods where we can. _Emission factors for freight by transport mode (kilograms of CO2eq per tonne-kilometer)_{ref}These emissions factors by transport mode are those applied in the analysis by Joseph Poore and Thomas Nemecek (2018), published in _Science_. These emission factors are sourced from [Ecoinvent v3.3](https://www.ecoinvent.org/database/ecoinvent-33/ecoinvent-33.html), a comprehensive database which is commonly used in international life-cycle analyses (LCA). Emission factors can span a range of values depending on factors such as the efficiency of vehicle used; packing/loading density of freight; distribution between passenger and freight allocation in shared transport; amongst other factors.{/ref} Which foods are air-freighted? How do we know which products to avoid? Foods which are air-freighted tend to be those which are highly perishable. This means they need to be eaten soon after they’ve been harvested. In this case, transport by boat is too slow, leaving air travel as the only feasible option. Some fruit and vegetables tend to fall into this category. Asparagus, green beans and berries are common examples of air-freighted goods. It is often hard for consumers to identify foods that have travelled by air, since they’re rarely labeled as such. This makes them hard to avoid. A general rule is to avoid foods that have a very short shelf-life _and_ have traveled a long way (many labels have the country of ‘origin’ which helps with this). This is especially true for foods where there is a strong emphasis on ‘freshness’: for these products, transport speed is a priority. ## Additional information Let’s take the example of asparagus. If you live in the UK, you may have noticed on food labels that asparagus is often imported from Peru. They often come by plane. How does this affect their carbon footprint? The average carbon footprint of asparagus is around 0.4 kilograms CO2eq per kilogram. Flying from Lima to London [is around](https://www.entfernungsrechner.net/en/distance/city/2643743/city/3936456) 10,000 kilometers. If we were to fly one kilogram of asparagus over this distance, this would emit around 11 kilograms of CO2eq [10,000km * 1.13 kilograms CO2eq per tonne-kilometer for flying / 1000 = 11.3 kg CO2eq per kg]. Suddenly the footprint of your asparagus changes from being a low-carbon food to a relatively high-carbon one, at almost 12 kg CO2eq per kg. It has a higher carbon footprint that a kilogram of chicken or pork. It is the fact that it’s flown, rather than the travel distance itself that gives asparagus a large footprint in this example. If it traveled the same distance by boat, the travel emissions would be only 0.26 kg CO2eq per kg [10,000km * 0.026 kilograms CO2eq per tonne-kilometer for transport by boat / 1000 = 0.26 kg CO2eq per kg]. So its total footprint would be around 0.67 kg CO2eq per kg, which still makes it a low-carbon food option. | {
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"content": "\n<p>People often think that eating \u2018local\u2019 \u2013 buying foods which are produced close to home \u2013 is one of the most effective ways to reduce our carbon footprint.</p>\n\n\n\n<p>This is certainly true for foods that are transported by plane. But the reality is that very little of our food is.</p>\n\n\n\n<h3>Most food travels by sea, not by air</h3>\n\n\n\n<p>One simple way to compare the means of transport for food is to sum up how many kilometers planes with food freight travel; and compare this to how how many kilometers trains, and ships, and trucks do.<br><br>But this does not give the complete picture because a boat can carry much more food for a given distance than a truck can. To give an informative comparison, we use a metric called \u2018food miles\u2019; this is calculated as the distance each transport method covers multiplied by the quantity of food transported (by mass). This gives us a comparison of food miles in tonne-kilometers.</p>\n\n\n\n<p>The chart here shows the share of global \u2018food miles\u2019 by transport method. This data is sourced from the work of Joseph Poore and Thomas Nemecek, published in the journal <em>Science</em> in 2018.{ref}Poore, J., & Nemecek, T. (2018). <a href=\"https://science.sciencemag.org/content/360/6392/987\">Reducing food\u2019s environmental impacts through producers and consumers</a>. <em>Science</em>, 360(6392), 987-992.{/ref}</p>\n\n\n\n<p>As the data here shows, only 0.16% of food miles come from air travel. Most \u2013 nearly 60% \u2013 comes by boat.</p>\n\n\n\n<p>You can see this data in absolute terms, in tonne-kilometers, <a href=\"https://ourworldindata.org/grapher/food-miles-by-transport\"><strong>here</strong></a>.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/share-food-miles-by-method\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>Whether food travels by sea or air makes all the difference</h3>\n\n\n\n<div class=\"wp-block-columns\">\n<div class=\"wp-block-column\">\n<p>Transporting food by air emits around 50 times as much greenhouse gases as transporting the same amount by sea. More specifically, 0.023 kilograms of carbon dioxide-equivalents (CO<sub>2</sub>eq) per tonne-kilometer by sea, versus 1.13 kilograms CO<sub>2</sub>eq by air. We see these emission factors for different transport modes in the table.</p>\n\n\n\n<p>For food that is transported by sea, transportation doesn\u2019t actually add much to the carbon footprint. Since most of our food is transported by sea, transport emissions only account for 6% of the carbon footprint of food, on average.{ref}You might think that this figure of 6% is strongly dependent on where in the world you live \u2013 that if you live somewhere very remote, that the role of transport must be much higher. But this is not really the case. </p>\n\n\n\n<p>Let\u2019s take the example of beef from a beef herd. The average footprint of this beef is approximately 60 kilograms of CO<sub>2</sub>eq per kilogram of beef. Let\u2019s compare the transport footprint of buying from your local farmer (who lives just down the road from you), versus someone in the UK transporting beef from Central America (approximately 9000 kilometers away).</p>\n\n\n\n<p>Transporting food by boat emits 0.023 kilograms of CO<sub>2</sub>eq per tonne of product per kilometer. To transport the 9000 kilometers from Central America to the UK therefore emits 0.207 kilograms CO<sub>2</sub>eq [9000km * 0.023kg per tonne-kilometer / 1000 = 0.207 kg CO<sub>2</sub>eq per kg]. This is only equivalent to 0.35% of the total footprint of the 60 kilograms of CO<sub>2</sub>eq per kilogram of beef. <br><br>If you buy from your local farmer \u2013 let\u2019s assume you walk there, and have zero transport emissions \u2013 your beef footprint is 59.8 kilograms CO<sub>2</sub>eq per kilogram [we calculate this as 60kg – 0.2kg]. It makes almost no difference.<br><br>Especially for foods with a large footprint, transport as a share of the food\u2019s total emissions is fairly insensitive to the distance travelled.{/ref}</p>\n\n\n\n<p>But for those food items that travel by air, travel distance <em>does</em> have a large impact. We should avoid air-freighted goods where we can.</p>\n</div>\n\n\n\n<div class=\"wp-block-column\">\n<p><em>Emission factors for freight by transport mode (kilograms of CO<sub>2</sub>eq per tonne-kilometer)</em>{ref}These emissions factors by transport mode are those applied in the analysis by Joseph Poore and Thomas Nemecek (2018), published in <em>Science</em>. These emission factors are sourced from <a href=\"https://www.ecoinvent.org/database/ecoinvent-33/ecoinvent-33.html\">Ecoinvent v3.3</a>, a comprehensive database which is commonly used in international life-cycle analyses (LCA). Emission factors can span a range of values depending on factors such as the efficiency of vehicle used; packing/loading density of freight; distribution between passenger and freight allocation in shared transport; amongst other factors.{/ref}</p>\n\n\n\n\n<table id=\"tablepress-120\" class=\"tablepress tablepress-id-120\">\n<thead>\n<tr class=\"row-1 odd\">\n\t<th class=\"column-1\">Transport mode</th><th class=\"column-2\">Ambient transport (kg CO<sub>2</sub>eq per tonne-kilometer)</th><th class=\"column-3\">Temperature-controlled transport (kg CO<sub>2</sub>eq per tonne-kilometer)</th>\n</tr>\n</thead>\n<tbody class=\"row-hover\">\n<tr class=\"row-2 even\">\n\t<td class=\"column-1\">Road Transport</td><td class=\"column-2\">0.2</td><td class=\"column-3\">0.2 to 0.66</td>\n</tr>\n<tr class=\"row-3 odd\">\n\t<td class=\"column-1\">Rail Transport</td><td class=\"column-2\">0.05</td><td class=\"column-3\">0.06</td>\n</tr>\n<tr class=\"row-4 even\">\n\t<td class=\"column-1\">Sea / Inland Water Transport</td><td class=\"column-2\">0.01</td><td class=\"column-3\">0.02</td>\n</tr>\n<tr class=\"row-5 odd\">\n\t<td class=\"column-1\">Air Transport</td><td class=\"column-2\">1.13</td><td class=\"column-3\">1.13</td>\n</tr>\n</tbody>\n</table>\n\n</div>\n</div>\n\n\n\n<p>Which foods are air-freighted? How do we know which products to avoid?</p>\n\n\n\n<p>Foods which are air-freighted tend to be those which are highly perishable. This means they need to be eaten soon after they\u2019ve been harvested. In this case, transport by boat is too slow, leaving air travel as the only feasible option. </p>\n\n\n\n<p>Some fruit and vegetables tend to fall into this category. Asparagus, green beans and berries are common examples of air-freighted goods.</p>\n\n\n\n<p>It is often hard for consumers to identify foods that have travelled by air, since they\u2019re rarely labeled as such. This makes them hard to avoid. A general rule is to avoid foods that have a very short shelf-life <em>and</em> have traveled a long way (many labels have the country of \u2018origin\u2019 which helps with this). This is especially true for foods where there is a strong emphasis on \u2018freshness\u2019: for these products, transport speed is a priority.</p>\n\n\n\t<block type=\"additional-information\" default-open=\"false\">\n\t\t<content>\n\n<h3>Example: how does the footprint of vegetables change if they travel across the world by plane vs. boat?</h3>\n\n\n\n<p>Let\u2019s take the example of asparagus. </p>\n\n\n\n<p>If you live in the UK, you may have noticed on food labels that asparagus is often imported from Peru. They often come by plane. How does this affect their carbon footprint?<br><br>The average carbon footprint of asparagus is around 0.4 kilograms CO<sub>2</sub>eq per kilogram. Flying from Lima to London <a href=\"https://www.entfernungsrechner.net/en/distance/city/2643743/city/3936456\">is around</a> 10,000 kilometers. If we were to fly one kilogram of asparagus over this distance, this would emit around 11 kilograms of CO<sub>2</sub>eq [10,000km * 1.13 kilograms CO<sub>2</sub>eq per tonne-kilometer for flying / 1000 = 11.3 kg CO<sub>2</sub>eq per kg]. Suddenly the footprint of your asparagus changes from being a low-carbon food to a relatively high-carbon one, at almost 12 kg CO<sub>2</sub>eq per kg. It has a higher carbon footprint that a kilogram of chicken or pork.<br><br>It is the fact that it\u2019s flown, rather than the travel distance itself that gives asparagus a large footprint in this example. If it traveled the same distance by boat, the travel emissions would be only 0.26 kg CO<sub>2</sub>eq per kg [10,000km * 0.026 kilograms CO<sub>2</sub>eq per tonne-kilometer for transport by boat / 1000 = 0.26 kg CO<sub>2</sub>eq per kg]. So its total footprint would be around 0.67 kg CO<sub>2</sub>eq per kg, which still makes it a low-carbon food option.</p>\n\n</content>\n\t</block>"
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