A New, More Violent Rhythm of Rain
The fundamental nature of India's rainfall is shifting. It’s not simply about more or less rain annually, but how it arrives. Climate scientists have observed a disturbing trend: fewer rainy days interspersed with long dry spells, followed by short, intense
bursts of extreme downpour. Research shows widespread extreme rain events across central India have tripled since 1950. This pattern of 'feast or famine' disrupts the delicate balance that forests have adapted to over millennia. Instead of gentle, sustained moisture that nurtures soil and seeds, forests are now subjected to violent deluges that can be as damaging as a drought.
Soil, Slopes, and Landslides
The country's mountainous forests, particularly in the Himalayas and the Western Ghats, are on the front lines of this change. Intense rainfall on steep slopes saturates the soil far quicker than it can be absorbed. This leads to increased soil erosion, washing away the nutrient-rich topsoil that trees depend on for sustenance. In the worst cases, this soil saturation triggers landslides, which can decimate entire patches of forest in an instant, leaving barren scars on the landscape. The Himalayan region is warming at nearly twice the global average, leading to more unseasonal rains that destabilise slopes and increase the frequency of such devastating events. This not only destroys vegetation but also damages the very foundation upon which the forest ecosystem is built.
The Double Threat of Drought and Fire
The other side of extreme rain is the increased frequency and duration of droughts. The long, dry spells between torrential downpours stress forest ecosystems immensely. Trees become weaker, more susceptible to pests and diseases, and their growth is stunted. This prolonged dryness creates a tinderbox effect. With less moisture in the soil and vegetation, forests become highly vulnerable to fires. Studies show a strong link between rising temperatures, erratic rainfall, and an increase in forest fire frequency and intensity, especially in central India, the Himalayas, and the Western Ghats. Some models predict the severe fire season in Central India could extend by over 60 days by the end of the century.
A Cascade of Consequences for Ecosystems
These changes don't just affect trees; they trigger a cascade of consequences for the entire ecosystem. In the Himalayas, warming and altered precipitation are forcing plant and animal species, including the elusive snow leopard, to move to higher altitudes where survival is uncertain. In central India, a study of the Panchmarhi Biosphere Reserve found that it lost 13% of its forest cover between 1972 and 2020, partly due to climate shifts that favoured scrubland over dense forest. The very composition of forests is changing, with some studies suggesting a potential shift from stable forests toward more savanna-like vegetation in areas with high rainfall variability. This loss of biodiversity threatens the intricate web of life and the essential services, from clean water to carbon storage, that these forests provide to millions of people.
