By: Olga Makarova,
PR Manager, OpenWeather 

Solar radiation is the main source of energy for all processes, which occur in the atmosphere and on the Earth’s surface. Its intensity has a profound impact on the chemical composition of plants, and subsequently, on the quality of agricultural crops. As to whether these changes – caused by an increase or decrease in the flux of UV radiation – are significant or insignificant or indeed constructive or harmful, depends on many factors.  

On the one hand, UV radiation favorably influences the life cycle of plants, it boosts the intensity of photosynthesis processes, facilitating the production of chlorophyll and nutrient absorption.  

On the other hand,  excessive UV exposure can cause protein degradation in leaf cells, leading them to die. Plants possess the ability to repair damaged DNA while several are able to protect themselves from synthesizing absorbed ultraviolet light pigment and from changes to key metabolic enzymes.    The danger occurs when the dose of radiation causes damage which exceeds a plant’s regeneration capabilities.   The damage leads to a decrease in crop yields, fertility, commercial quality and severe consequences, such as changes weed-crop synergies.

The impact of UV radiation on agricultural crops can be extremely complex in nature.   For example, for several types of crops, more damage occurs in plants with a high moisture content, than those found in very dry conditions*.  It has also been observed that crops have differing levels of sensitivity to UV radiation.

It is clear that for monitoring the crop life cycle, forecasting crop yields, best management practices and minimizing any negative impact, cutting-edge instruments, aimed at providing access to as much accurate information as possible according to as many indicators as possible, are required.    

One such indicator, which can be applied to carry out complex analysis as well as an evaluation of any given situation, is the UV-index (Clear Sky).

The clear sky UV-index is a tool for effective UV radiation measurement (1 unit is equal to 25 MW/ m2), for UV rays reaching the Earth’s surface.   It is functional in cloudy conditions at midday local time, i.e. when the sun is at the highest point on the horizon and thus there is maximum UV coverage.    

We provide real-time and historical data with the UV index (Clear Sky) for any geolocation (latitude/longitude), as well as a current and 7-day forecast.    Historical data is available from as far as summer 2017.

* For plant moisture surplus/deficits there are vegetation indices such as NDWI, NDVI, EVI.