Enhanced aurora borealis forecasting service promises greater precision

By admin On Jan 24, 2024

Aurora borealis (nothern lights). Photo: Svein-Magne Tunli

A significant upgrade has been made to the real-time aurora borealis (northern lights) forecasting service, enhancing the accuracy and user experience for those eager to witness this natural spectacle. The service, which has been operational for about 20 years, utilizes fluctuations in the Earth’s magnetic field to predict the likelihood of aurora appearances.

The key enhancement in the service is the introduction of two threshold values instead of one.

These thresholds are based on data analysis of 146,747 images from aurora borealis cameras in Kevo, Muonio, and Hankasalmi. These images captured 463 hours of aurora displays, including moments of dark sky, providing valuable statistical data.

The higher threshold value, similar to the previous single threshold, indicates a strong likelihood of a vivid aurora display. When this level is exceeded, the service’s map and bar chart indicators turn red, as was the case previously. The new addition is a lower threshold, represented by yellow markers on the map and charts. Exceeding this lower threshold suggests a possibility of aurora visibility, though likely in a dimmer and more subdued form. Each observation station has its unique threshold values, illustrated as horizontal lines in the bar chart.

Another significant change is the introduction of the R-index (Revontuli Index), named after the Finnish word for aurora borealis. This index measures the rate of change in the magnetic field but is not tied to physical units. Typically represented as an integer in tens or hundreds, the R-index offers a more intuitive understanding of auroral activity.

The R-index calculation frequency has been doubled, now updated every five minutes instead of ten, bringing the service closer to real-time monitoring.

Accessibility improvements include a redesign of the map markers: yellow squares and red rhombuses replace the previous color-only system, aiding those with color vision deficiencies to distinguish between different levels of auroral activity.

These enhancements make the aurora borealis service more reliable and user-friendly, promising a better experience for enthusiasts and researchers alike. This upgrade is a significant step forward in aurora forecasting, potentially increasing the success rate for those hoping to witness one of nature’s most mesmerizing phenomena.

Source: www.helsinkitimes.fi