Fukuoka, Japan – Scientists at Kyushu University have unveiled a groundbreaking numerical tool to decode sunlight patterns, aiming to revolutionize farming. This clever model, detailed in Ecological Informatics, tracks how sunlight shifts with weather, offering farmers a way to supercharge crop growth. Unlike older methods obsessed with sunlight as raw energy, this study measures its intensity and impact on plants, from blooming to photosynthesis. It’s a game-changer for agriculture, especially as cloud cover shifts with climate change, affecting how plants soak up carbon dioxide.

Everyone knows plants thrive on sunlight for photosynthesis, but more isn’t always better. Cloudy days, with light scattered evenly, can outshine sunny ones by reaching a plant’s lower leaves. On clear days, intense sunlight blasts from one angle, leaving shaded leaves starved. “Plants sense wavelengths like a rainbow,” says Amila Siriwardana, a PhD student at Kyushu University’s Faculty of Agriculture. “They tweak their growth based on these signals.”

To crack this, the team used a spectroradiometer atop their agriculture building, logging sunlight data all day, every day in 2021. Feeding this into a machine learning model, they sorted sunlight into five types—clear skies to thick clouds. Clear days pack more energy, but overcast ones scatter light better, boosting ultraviolet rays and shifting colors from red to blue. With 94% accuracy, the model predicts sunlight using basic weather stats like humidity or pollution.

Led by Professor Atsushi Kume, the researchers want farmers to harness this. In Japan’s rainy June, cloudy light could guide greenhouse tweaks or crop spacing. Even in winter, it could fine-tune planting. “It’s about smarter farming,” Kume says. Next, they’re eyeing tropical and high-altitude zones to broaden the tool’s reach.

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