Spring tides are a type of tidal phenomenon characterized by particularly high and low tides. They occur when the gravitational forces of the Moon and the Sun are aligned, either during the new moon or the full moon phases. During these periods, the combined gravitational pull of the Moon and the Sun creates a greater difference between high and low tides compared to other times.

Key Points:

1. Alignment of Gravitational Forces
   Spring tides occur when the Earth, Moon, and Sun are in alignment. This alignment can happen during:
   • New Moon: When the Moon is between the Earth and the Sun, the gravitational forces of the Moon and the Sun are combined.
   • Full Moon: When the Earth is between the Moon and the Sun, the gravitational forces are also aligned.
2. Tidal Range
   During spring tides, the tidal range (the difference between high and low tides) is at its maximum. This results in higher high tides and lower low tides. The increased tidal range can lead to more pronounced effects on coastal environments, including erosion and flooding.
3. Recent Examples:
   • Cyclone Amphan (2020): The powerful spring tides coincided with Cyclone Amphan’s landfall, causing severe flooding in coastal areas of West Bengal and Bangladesh. The combination of spring tides and the cyclone’s storm surge exacerbated the impact on the affected regions.
   • Tsunami Events: Spring tides have been observed to influence the extent of flooding in tsunami events. For instance, the spring tide conditions during the 2011 Japan tsunami contributed to the severity of the flooding in coastal areas.
4. Frequency and Predictability
   Spring tides occur approximately every two weeks, coinciding with the new moon and full moon phases. They are predictable and can be forecasted using tidal charts and astronomical data. Coastal communities often prepare for these high and low tides to manage potential impacts on fishing, shipping, and coastal infrastructure.
5. Global Impact
   • United Kingdom: In the UK, spring tides are carefully monitored as they can impact maritime activities and coastal defenses. For instance, during spring tides in the winter months, there is a higher risk of coastal flooding in regions like East Anglia.
   • India: In India, spring tides can significantly affect the Sundarbans region, where the tidal variations can influence the local mangrove ecosystem and impact local communities. For example, during the spring tides of 2023, the Sundarbans saw increased salinity levels in the water, affecting agriculture and fisheries.

Conclusion

Spring tides are significant tidal events that occur when the gravitational forces of the Moon and the Sun are aligned with the Earth, leading to extreme high and low tides. These tides occur during the new moon and full moon phases and have notable impacts on coastal environments and human activities. Recent examples such as Cyclone Amphan and tsunami events demonstrate the importance of understanding and predicting spring tides for disaster preparedness and coastal management.