IIT-K researchers develop world's first 3D data-based model to predict solar activity

New Delhi, Feb 24 (PTI) Researchers at the Indian Institute of Technology (IIT) Kanpur have developed the world's first three dimensional data-driven model to predict solar activity, contributing towards monitoring space weather.

Solar activity, including solar storms, is governed by a cyclic intensifying and weakening of the internal dynamo process, which creates the Sun's magnetic field. One cycle of solar activity, involving a peak maxima of heightened activity and a minima of reduced activity, typically spans about 11 years.

A huge amount of charged particles, energy and magnetic fields can be discharged into the Solar System during a solar storm. On Earth, the sudden influx of cosmic particles can disrupt satellite-based services and cause communication blackouts, potentially bringing modern society to a standstill.

The duo of physicists Gopal Hazra and Soumyadeep Chatterjee say that if the 3D model -- first of its kind in the world -- is fed with observations of the solar surface of at least 11 years, it can estimate solar activity, also called 'sunspot' activity, up to five years in the future. Sunspots are active regions on the Sun's surface that can trigger solar storms and solar flares.

"What will be the scenario then? How many flares, how many solar storms will occur? We can estimate, for example, on the basis of the presence of a lot of sunspots, a possibility that a solar storm will occur," Hazra said on a video call with PTI.

The model, described in a paper published in January in The Astrophysical Journal Letters, is among the many efforts around the world directed at tracking space weather to issue timely alerts of disruptions from the Sun -- but the IIT-K model is the first data-driven three dimensional one.

"To the best of our knowledge, we are the first ones to do this kind of 3D mapping and solar cycle prediction using fully observational data and no other group in the world has done this before," Hazra said.

The researchers modelled the interior magnetic fields of the Sun using past three decades of data of surface magnetic fields, recorded by past missions of the US' NASA and the European Space Agency (ESA).

Experts said the 3D model adds to a growing body of independent research on Sun's activity and provides a method to link observations of solar surface with theoretical predictions of how strength of a solar cycle changes.

Prasad Subramanian, faculty at the Indian Institute of Science Education and Research (IISER), Pune, said, "The study is interesting and thorough. The findings are significant, because they suggest a concrete pathway for using observations to connect with theoretical predictions of the solar cycle strength." The study also represents a contribution from India to long-term space 'climate' predictions, rather than short-term space 'weather' ones, he said.

However, the model might be somewhat limited in forecasting a future solar cycle "because it requires data to be incorporated well after the current cycle has already started. So it loses the long term predictive value that earlier (2D) models have already demonstrated," said Dibyendu Nandi, a space weather expert and professor at IISER, Kolkata.

He noted that decade-old models from earlier studies assimilate observations of magnetic fields on the Sun's surface into 2D models to predict solar activity, whereas the novelty of the IIT-K study is that it directly assimilates surface observations into a 3D dynamo model.

"The most valuable contribution in my opinion from this work is that it adds to a growing body of independent research works, and a purely analytical theory which posits that the solar surface field is the primary source of the magnetic field production process in the solar interior, which drives the solar cycle," Nandi said.

He added that the 3D model may be more suitable for making a short-term forecast and is an important contribution towards monitoring space weather. PTI KRS MG MG