At noon on 25 April 2015, within just ten seconds, Kathmandu Valley was shifted five feet to the south, together with all its people and houses, temples and trees. In this geological movement, described in this issue by seismologist Roger Bilham, those of us at Himal were fortunate enough to be spared the worst. Yet the immediacy of the disaster and the proximity of the tragedy have certainly left its mark, prompting us to put together this quarterly on disasters in Southasia.
Our first challenge was identifying the scope of the issue. Given the scale and increasing frequency of disasters in Southasia, we decided to limit the theme to natural disasters, but were then faced with the challenge of defining 'natural'. Earthquakes, such as the recent one in Nepal, can be ascribed to the wholly natural movements of tectonic plates miles below the surface of the earth, even though they are now being triggered by human activities, such as oil extraction and large reservoirs.
However, when it comes to devastation caused by other natural phenomena such as floods and landslides, the lines are blurred. What is the impact of damming rivers on the subsequent fury of its waters? Does the natural ebb and flow of water become disastrous because human settlements and infrastructures are too close to the banks? Do landslides bury villages because of deforestation further up the slopes? Are these disasters manmade or natural, or a combination of both? As Nityanand Jayaraman writes in this issue, the development of the Tamil Nadu coastline for tourism and urban dwellings has eroded natural shock absorbers such as estuaries, mangroves and flats, leaving it more vulnerable to tidal waves including tsunamis.
This issue largely leaves out those disasters triggered primarily by human involvement (such as the 1984 Bhopal gas disaster), but does consider human factors, in the form of political and economic arrangements, that shape the impact of natural events. Though nature's fury is often seen as a great equaliser, indiscriminate in its choice of victims, the disproportionate impact of disasters on the poor and the marginalised was evident in Nepal. The majority of deaths occurred in town and country due to the collapse of houses made with mud-mortar. There was also inequality in the response that followed, with villages in remote valleys not only suffering from the absence of immediate rescue, but also falling victim to uneven relief. Rehabilitation and reconstruction efforts are expected to be tilted against the poor in the remote regions.