On July 30, two villages, Mundakkai and Chooralmala, within the Wayanad district of Kerala, have been hit by landslides. On October 4, whereas noting that the catastrophe ranked among the many deadliest in India, Chief Minister Pinarayi Vijayan stated that 231 folks had died and 41 remained lacking. The catastrophic occasion has as soon as once more uncovered our helplessness within the face of nature’s fury. On the similar time, it has raised questions on our strategy to catastrophe administration not solely within the space of Wayanad that was affected this time and that has suffered just a few lethal landslides during the last 4 a long time, however for the State as an entire.
Not comparatively disaster-free
With the ocean to its west and the Western Ghats to its east, Kerala was once thought of a comparatively disaster-free zone. Its growth actions have taken place on this premise. Settlements are distributed all through the State, from the shoreline to the steep hill slopes. Kerala is probably the one State the place human settlements have sprung up alongside the coastal line. Although the forest boundary is frozen, there are encroachments by the folks and for growth tasks. Together with settlements, roads and different infrastructure have been constructed with full disregard for pure drainage and slope stability. The typical inhabitants density of the elements of the Western Ghats in Kerala is nicely above the all-India common.
The pure benefit of being comparatively disaster-free appears to be waning. In the previous couple of a long time, the depth and frequency of disasters have elevated. Kerala has three distinct geographic zones, and all three are going through disasters, particularly floods and landslides. Coastal erosion, an everyday phenomenon, has affected greater than 250 kilometres of the whole coastal size of 590 km within the State. In addition to, sea surge has affected totally different elements of the coast. The lowlands and midlands undergo from floods. Components of the lowlands surrounding the Vembanad lake get inundated throughout each monsoon. The World Meteorological Group described the Kerala floods of 2018 because the ‘floods of the century’ and attributed the catastrophe to local weather change. Landslides within the Western Ghats are additionally turning into common throughout each monsoon.
Landslide stock map wanted
Wayanad, situated to the east of the Western Ghats bordering the Mysore plateau, is characterised by deep gorges and ravines. Just like the river Sharavati, the Chaliyar additionally originates within the japanese aspect of the Western Ghats. Each these rivers reduce throughout the mountain vary and debouch into the Arabian Sea, despite the easterly tilt of the Wayanad-Mysore plateaus. This may be attributed to the existence of tectonic components. A spatial correlation exists between tremors and landslides. Incidences of fractures/cracks have been reported from Wayanad and Idukki put up landslides. Tremors have been felt in elements of Wayanad after the July landslide as nicely. Recurring incidences of landslides and the large human and financial losses name for scientific re-appraisal of the causative components, which are actually being simplified and confined to parameters reminiscent of slope, soil thickness, rainfall depth and period, and land use change. The continued debates present that there’s a hole in understanding the incidence of landslides on this area.
World analysis on this area requires a nuanced strategy. We want a landslide stock map of every area/space. To finalise zones prone to landslides, we are able to put together a landslide susceptibility map factoring within the geological arrange (lithology, construction and tectonics, rock composition, physico-mechanical properties), slope, soil traits, hydrologic parameters, drainage and infiltration, vegetation cowl, human actions reminiscent of mining and quarrying, slope alteration, and agricultural actions. As soon as such maps surrounding inhabitants centres are prepared, monitoring the triggering mechanism (rainfall or tremors within the case of Kerala) would be sure that well timed warnings of landslides are offered, and lives saved. The State and educated native self-help teams can do that collectively.
As a consequence of fast warming of the Arabian Sea, there may be an elevated threat of utmost climate and local weather occasions, reminiscent of floods, warmth waves, and cyclones. The warmth content material of the Indian Ocean has risen quickly because the 2000s. There was an anomalous improve of 1.2°C in summer season sea floor temperatures during the last 100 years within the usually cool western Indian Ocean (Arabian Sea). This has created an surroundings conducive for cyclogenesis (growth or strengthening of cyclonic circulation within the environment) within the Arabian Sea. The affect of those modifications is being felt on Kerala. In 2017, Cyclone Ockhi hit the State. It was probably the most extreme cyclonic storm to have an effect on Kerala in latest reminiscence.
Editorial | Unnatural catastrophe: On the Wayanad landslides
On the entire, the ‘safe operating space’, a time period coined by Johan Rockstrom and the group on the Stockholm Resilience Centre within the case of world environmental change, is shrinking in Kerala. The prevalence of staggered occasions of floods and landslides, and simultaneous landslides on both aspect of the hill ranges, as in Wayanad and Vilangad (Kozhikode district) this time, and at Puthumala (Wayanad district) and Kavalappara (Malappuram district) in 2019, additionally warrant elucidation.
A paradigm shift
Beneath these circumstances, there’s a want for a paradigm shift in catastrophe administration practices, that are principally reactive, top-down, and revolve round rescue, reduction, and rehabilitation. Globally, this has given method to a extra proactive and complete strategy of addressing all points of a catastrophe cycle, reminiscent of preparedness, resilience, threat discount, mitigation, reconstruction, restoration, response, and reduction. The Sendai Framework for Catastrophe Danger Discount offers pointers for catastrophe threat discount. It recognises the first position of the State in catastrophe threat discount however says that the State ought to share this duty with different stakeholders together with native governments, the non-public sector, and communities. We have to perceive the chance of catastrophe, strengthen catastrophe threat governance to handle the chance of catastrophe; put money into catastrophe threat discount for resilience; and improve catastrophe preparedness for efficient response to ‘build back better’.
First, Kerala must work out catastrophe threat zones primarily based on a number of standards overlaying each bodily and social parts inside a social ecological body with the assistance of topic consultants and generate a everlasting database. As landslides and floods observe watershed boundaries, the catastrophe threat zones should be translated based on the watersheds/river basins. Second, Kerala wants the folks’s participation in making ready catastrophe threat maps. Given its expertise within the Folks’s Plan Marketing campaign, it can be crucial for Kerala to introduce a community-based catastrophe threat administration by which at-risk communities are actively engaged in figuring out, analysing, planning, implementing, monitoring, and evaluating catastrophe threat discount initiatives. This would supply alternatives for strengthening communication, dialogue, and studying inside the group and between the group and the native and Central authorities. It might additionally guarantee a bottom-up strategy, assist scale back rigidity and potential conflicts and pave the best way to combine catastrophe threat administration in native stage growth. A quadruple helix mannequin involving group and social organisations, academia/analysis institutes, the federal government, and enterprise and business could also be helpful.
Srikumar Chattopadhyay, Scientist (retired), Centre for Earth Science Research, Thiruvananthapuram; Okay. Soman, Scientist (retired), Centre for Earth Science Research, Thiruvananthapuram
Revealed – October 05, 2024 01:26 am IST
