Sandra Solstad: To make the relative carbon impact of different foods easier to understand or to digest, we propose a banana index. What we've done is we compared public food stuff on weight calories and protein to the fruit that's middle of the road in all three categories. And you can check it out online and look up your favorite foods.
Clashes in Khartoum have turned deadly as two rival military factions fight for power. As the conflict escalates, a transition to civilian rule could be in jeopardy. Europe’s cities have a worrying pollution problem and clearing the air is proving difficult. And a new way to measure the environmental impact of food.
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