Measuring wine quality from orbit
BBC News: English wine gets help from space
The ‘help’ is satellite imagery from a company called Infoterra, specifically their “Oenoview” system. And although the BBC likes the British angle, some French vineyards aren’t too proud to ignore it (Link 1, Link 2).
It’s hard to discern what it actually does (this may be intentional on Infoterra’s part, of course), but here’s my best guess:
- By finding the ratios of how well an area reflects different colours (wavelengths) of light, they can work out how much chlorophyll is present. This is already done to map algae in the oceans.
- The BBC mentions leaf area index. This is measured in m² of leaf per m² of ground; if an ant was to look up, LAI is the average number of leaf layers directly above it. I’d assume they’re simply taking this from the amount of chlorophyll. More leaves means more sugar going into the grapes.
- A couple of the sources talk about the infrared, and sensing water status. This could just be done through what I’ve mentioned above (leafier plants have probably had more water), but I suspect they’re also doing thermal imaging, which uses long wavelength infra-red. Plants with plenty of water will be cooler, due to evaporation. Obviously, like any plant, they need enough water to grow, but as one of the French vignerons points out, the wine actually benefits from some level of water stress after the grapes have formed.
Infoterra also offer something similar for more general agriculture, although the wine industry, with its valuable product, is probably easier to sell this to.