The new research was led by Irina Kitiashvili, a researcher with the Bay Area Environmental Research Institute at NASA’s Ames Research Center, in California’s Silicon Valley. It combined observations from two NASA space missions – the Solar and Heliospheric Observatory and the Solar Dynamics Observatory – with data collected since 1976 from the ground-based National Solar Observatory.
One challenge for researchers working to predict the Sun’s activities is that scientists don’t yet completely understand the inner workings of our star. Plus, some factors that play out deep inside the Sun cannot be measured directly. They have to be estimated from measurements of related phenomena on the solar surface, like sunspots.
Kitiashvili’s method differs from other prediction tools in terms of the raw material for its forecast. Previously, researchers used the number of sunspots to represent indirectly the activity of the solar magnetic field. The new approach takes advantage of direct observations of magnetic fields emerging on the surface of the Sun – data which has only existed for the last four solar cycles.
Mathematically combining the data from the three sources of Sun observations with the estimates of its interior activity generated a forecast designed to be more reliable than using any of those sources alone.
In 2008 the researchers used this method to make their prediction, which was then put to the test as the current solar cycle unfolded over the last decade. It has performed well, with the forecast strength and timing of the solar maximum aligning closely with reality.
Her results are as follows:
Using the currently available observational data, predictions and prediction uncertainties have been calculated for Solar Cycle 25. The results, based on both the sunspot number series and observed magnetic fields, indicate that the upcoming Solar Maximum (Solar Cycle 25) is expected to be significantly weaker than that of the current cycle (which near its end). The model results show that a deep extended solar activity minimum is expected in about 2019-2021, the maximum will occur in 2024 – 2025, and the sunspot number at the maximum will be about 50 (for the v2.0 sunspot number series) with an error estimate of ~15-30%. The maximum will likely have a double peak or show extended high activity over 2 – 2.5-years.
NOAA Has also released a more modest preliminary forecast for Solar Cycle 25 on April 5, 2019. Similar to Kitiashvili’s predictions they state Cycle 25 will be similar in size to cycle 24. It is expected that sunspot maximum will occur no earlier than the year 2023 and no later than 2026 (Kitiashvili’s Prediction 2024 – 2025), with a minimum peak sunspot number of 95 and a maximum of 130 (Kitiashvili’s Prediction 50). In addition, the panel expects at NOAA state the end of Cycle 24 and start of Cycle 25 to occur no earlier than July, 2019, and no later than September, 2020. The panel hopes to release a final, detailed forecast for Cycle 25 by the end of 2019. Please read the official NOAA press release describing the international panel’s forecast at https://www.weather.gov/news/190504-sun-activity-in-solar-cycle & Here
It will be interesting to see how Valentina Zharkova’s works stacks up against these two predictions! STAY TUNED!!