Spring tides refer to

Spring tides occur when the Sun, Moon, and Earth align in a straight line (syzygy), which happens during the full moon and new moon phases [3]. During this alignment, the gravitational forces of the Sun and the Moon combine to reinforce each other [1]. This additive effect results in higher-than-average high tides and lower-than-average low tides [1]. Consequently, spring tides are characterized by the greatest tidal range, which is the maximum vertical difference between the sea level at high and low tides [1]. In contrast, neap tides occur when the Sun and Moon are at right angles, causing their gravitational pulls to partially counteract each other, leading to the smallest tidal range [2]. Therefore, spring tides represent the period of the greatest difference in sea levels between high and low tide cycles.

Sources

1. [1] FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 13: Movements of Ocean Water > Tides based on the Sun, Moon and the Earth Positions > p. 110
2. [3] https://education.nationalgeographic.org/resource/cause-effect-tides/
3. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 32: Ocean Movements Ocean Currents And Tides > Neap Tides > p. 504