Solar activity, as seen in the forms of sunspots, coronal mass ejections (CMEs), solar flares, solar wind, irradiation variations, etc, is driven by the variable magnetic field of the Sun. Besides the 11-year oscillation (22 years when considering the polarity) of the solar magnetic field, there are variations in short-time scales, such as bursts of activity and double peaks of activity, and variations in the longer time scales as seen in the form of grand minima (e.g., Maunder minimum), the grand maxima (e.g., Modern maximum) and variations of strength in between these phases. Due to these variations, predicting solar activity is a highly challenging task. In the last decade, we have made a considerable amount of progress in understanding the origins of various forms of solar activity and their variations and in making reliable predictions of future activity level. Data from various observatories across the globe, including India's oldest observatory, Kodaikanal Solar Observatory have presented hidden information about solar activity and helped us to understand the causes of variations in the solar activity cycle. The ongoing Solar Cycle 25 is expected to peak around 2024. Therefore, it's an exciting time to bring the theoreticians, observers, modellers, and engineers from various subfields of solar and space physics to reflect upon the learnings from the different prediction methods developed over the years. It is also crucial to discuss the impact of solar activity on space weather, exchange different ideas on how to cross-calibrate data from different observations and utilize the data in various models to understand better and constrain the theoretical models. With this motivation, we propose a one-week international conference to primarily focus on the following topics:

• Availabilities of different ground and space-based data suitable for understanding the solar activity variations and prediction.
• Understanding and modelling various aspects of solar activity, with special emphasis on the long- and short-term modulations and grand minima and maxima.
• Connecting models with data and constraining various parameters of the models.
• Effects of solar activity on space weather, planetary interaction, and the prediction of solar activity.

How it will enhance capacity building:

During this event, we plan to bring scientists from very diverse topics of solar and space physics under the same umbrella; we shall exchange ideas, discuss the status of understanding and predicting solar activity and its variability and plan how to make a more accurate prediction. We shall also discuss how to utilize different data sets, cross-calibrate data and compare different models. This event will enhance capacity building among scientists working in various fields of solar and space physics. Younger generation scientists will benefit most from this event.

Mode of Conference:

Conference will be in person only and by invitation. Every day, there will be 3 sessions, 3 invited reviews (of 25+5 mints), 5 invited talks (of 20+5 mints duration) and 6 solicited presentations. Last day (Friday) we shall have 3-4 talks on Aditya-L1 and visit to Devasthal.

Due to a limited capacity of our conference hall, we shall plan that the participation to this conference will be by invitation only.