Millions of young people have risen up to fight the growing climate crisis through youth-led climate movements. Several factors are associated with youths’ engagement in climate protest, such as a desire to be with like-minded people and direct experience with the climate crisis. However, longitudinal research is needed to understand what sustains youth climate activism over the short-term. This dissertation uses three waves of original data collected from a sample of 193 young (18-24 years old) climate activists in India over 6 weeks in 2023. Multinomial logistic regression was used to examine the associations between seven factors (personal growth, sense of community, individual and collective agency, seeing tangible achievements, political repression, climate anxiety, and online and in-person harassment) and changes in youths’ level of climate activism (increased, stable, or decreased) cross-sectionally within each wave, and longitudinally across each pair of waves. The predictors were developed based on an inductive qualitative study (Wilf et al., under review). A Youth Research Advisory Board of 6 young Indian activists supported survey development and recruitment. Cross-sectional results showed that heightened personal growth, collective agency, and seeing tangible achievements from activism were associated with youths’ increased and stable compared with decreased activism, and that social media and in-person harassment were negatively associated with youth reporting stable compared with increased climate activism. Youth with heightened individual agency (power) were less likely to report increased or stable compared with decreased activism. Longitudinally, agency (competence) was positively associated with youths’ increased versus decreased activism, and negatively associated with youths’ stable versus increased activism. Across analyses, school and family responsibilities were significant deterrents to youths’ increased and stable activism, and religious minority youth were less likely to report stable compared with increased and decreased activism. In cross-sectional analysis, men were more likely to report increased and stable compared with decreased activism than women. Few of the results were consistent across waves, or in both cross-sectional and longitudinal analysis, and therefore should be interpreted with caution. This study provides insights into the factors that may shape short-term youth climate activism, with implications for scholars, climate movements, and youth-focused practitioners.