More than 1.3m hectares of the planet under glass or plastic

Using algorithms and modern sources of satellite imagery, University of Copenhagen researchers mapped the amount of land used for protected cropping worldwide, and said it has increased about four-fold in 40 years.

Growing in glass houses or in open fields wrapped in plastic films covers at least 1.3 million hectares of the Earth's surface, nearly three times more than previous estimates.

Using algorithms and modern sources of satellite imagery, University of Copenhagen researchers mapped the amount of land used for protected cropping worldwide, and said it has increased about four-fold in 40 years.