There is a particular feeling of helplessness that comes with being a seismologist when a disaster like the Nepal earthquake happens. I spend most of my day thinking about earthquakes in some capacity; I get a couple of alerts a day from the USGS about M3s and 4s in Oklahoma and think, ooh, data, or a M6 hundreds of kilometers deep where it will never be felt, but waking up to a 7.8 last Saturday provoked a moment of both clarity and confusion – that this one was going to mean something real and something terrible.
Even in distant parts of the world, we know within minutes or hours when an earthquake happens, but the aftermath unfolds more slowly. The death toll in Nepal continues to rise; as of the 2nd, it is over 7,000, with at least twice that injured. Damage to the capital Kathmandu is extreme, and the lack of roads, lack of helicopters, and landslides means that relief has been slow to reach the outlying rural areas where casualties and destruction are likely even higher. Rescue operations are still ongoing; just yesterday on the 2nd, a 101 year old man was pulled from the ruins of his home after a full week and is now in stable condition. Officials are pessimistic about finding more survivors however, particularly in the hill districts where entire villages have been destroyed.
On Mt. Everest, an avalanche shaken loose by the quake barreled through Base Camp; at least 19 were killed and hundreds of climbers stranded on the mountain. With descent routes made unsafe and the risk of aftershocks, many were airlifted from camps higher on the mountain. 10 of the dead identified so far were Sherpa climbing guides. Though the Chinese side of the mountain has shut down all expeditions for the season, the Nepali tourism department is encouraging climbers not to abandon their ascents, apparently feeling that “There is no scientific reason to expect another quake… and we feel the ground is stable enough for climbing despite aftershocks.” Aftershocks can continue for more than a year after the mainshock; the position seems like desperate attempt not to lose a second year in a row of Everest attempts by a country where tourism is the largest industry. In 2014, the climbing season was cut short by an avalanche which killed 16 Sherpas, which was then the deadliest disaster in the mountain’s history, and by subsequent protests for adequate compensation for the victims’ families. Nepal is one of the poorest countries in the world, and with the economic toll of the quake in the billions it now faces the task of trying to rebuild a tourism-heavy economy at the same time as rebuilding from the deaths and destruction – which includes many of Nepal’s historical landmarks.
Last week, my department held a special meeting of our Earthquake Record Reading seminar to discuss the quake. An emeritus professor who did some of the foundational work on the Himalayas in the ‘80s opened his presentation thus: Geologists like to quantify their ignorance. As much effort as we put into studying earthquakes and the Earth, it is often an exercise in hypotheticals. The tectonics, at least, are well known: the Himalayas, created by the plate-crunching union of India to Asia, are cut through by large thrust faults where the plates meet, capable of hosting large magnitude events. The biggest earthquake to happen in Nepal since 1934, this event was result of the rupture of one of these faults, with movements of 3 to 5 meters. Sitting in a seismically active region, Kathmandu is particularly vulnerable because it sits in a basin filled with lake sediments; the effect is like sitting atop a bowl of jelly. That’s the geological story; the meeting tended to skitter around the hole in the middle of our discussion: the human cost.
While we can’t predict earthquakes themselves, seismology and geology are vital for assessing potential for hazards, but it takes a wider political effort to do something about implementing that knowledge. Just this February, I read an NPR story about Kathmandu’s “Earthquake Lady” and the government’s attempts to regulate development and prepare for emergencies: http://www.npr.org/blogs/goatsandsoda/2015/02/25/388460206/please-dont-let-an-earthquake-hit-when-im-in-the-shower The predictions in the article – published 2 months to the day before the big quake – have been spot on. Building codes meant to increase resilience to shaking are ignored in favor of rapid expansion. With most older buildings made of unreinforced brick and stone construction, retrofitting existing buildings is expensive, and rapid urbanization means that vulnerable buildings and neighborhoods are often overpopulated, leading to the high death tolls.
One of the results of the Earthscope project which has covered much of the US in seismometers is the creation of some beautiful ground motion visualizations (GMVs). You can watch as the waves from the Nepal quake reverberate around the world: http://ds.iris.edu/spudservice/data/9925696 The world is starting to catch up to the speed of seismic waves, with international aid pouring in. In the aftermath, relief efforts are working hard to get essential supplies to survivors and to maintain sanitation to prevent outbreaks of disease, all while racing against the oncoming summer monsoons which will increase risks of mudslides and illnesses. Relief workers are using every tool at their disposal to maximize their efforts; for example, the Red Cross and the army are using drones and crowd-sourced scouring of satellite images to map what areas are hardest hit and figure out where to send relief. The Red Cross, UNICEF, and the UN World Food Program are all accepting donations, and Cornell has started a campaign at http://www.cornellfornepal.com/ which will send money to “Educate the Children.” The group is an Ithaca based NGO which focuses on helping women and children; their efforts in the wake of the earthquake will be concentrated on some of the rural communities which have been hardest hit. The full devastation of the quake will likely not be known for months, but efforts are digging in to keep worsening conditions at bay, and they could use as much help as possible.