In recent times, noticeable shifts in rainfall patterns have been observed in Northeast (NE) India, and these changes are largely attributed to Climate Change. There is a visible effect of this shift on various sectors including agriculture, fishing, and various ecosystems. This article delves into the causes, effects, and associated actions taken in response to these irregularities.
The National Action Plan and Climate Change
The Prime Minister’s Council on Climate Change launched the National Action Plan on Climate Change (NAPCC) in 2008. The objective of this plan is to facilitate measures that not only foster India’s growth but also make a positive impact on dealing with climate change efficiently.
Alterations in Monsoon Patterns
Northeast India is typically known for its heavy monsoon rainfall from June to September. However, recent years have witnessed an irregularity in these patterns. Intense bursts of rainfall leading to flooding, followed by extended dry spells characteristic of drought have become more common. A research paper published in 2018 revealed that the monsoon rainfall in the region had decreased by 355mm between the years 1979 and 2014.
Geographical Features and Rainfall
Geographical features like unique topology, steep slopes, and plains make NE India vulnerable to river course changing. Due to the hilly topography and its extension to the Indo-Gangetic Plains, this region is highly susceptible to regional and global climate changes. Decreasing rainfall trend has been noticed in most of the northeastern states during the monsoon season over two decades compared to the Long Period Average (LPA).
Factors Impacting Rainfall Patterns
Several factors contribute to the changes in these patterns. Global warming is resulting in the simultaneous increase in moisture and drying up of land. This not only alters rainfall patterns but also intensifies periods of drought. The monsoons are also impacted by increased snowfall in the Eurasian region and changes in the Pacific Decadal Oscillation (PDO) that lead to a weakened summer monsoon season. PDO is influenced by global warming, decreasing the temperature differences between ocean layers. Sunspot epochs, periods of increased and decreased activity on the sun’s surface, further modify the rainfall patterns.
Consequences of Altered Rainfall Patterns
Changes in rainfall patterns, particularly during the monsoon season, influence several ecological and economic aspects. These changes affect river flow, snow cover, and the health of mountain springs, leading to potential ramifications on agriculture and fishing industries, forest growth, and animal habitats. Evidence suggests that rivers including Subansiri, Dibang and Brahmaputra have been changing their courses unexpectedly. Extreme rainfall events caused by global warming have triggered soil erosion, increasing the surface run-off of rivers and subsequent alterations in their course.
