The immediate cause of everyone’s distress is an untoward sequence of weather events. A bone-dry summer last year was followed by a winter of unusually high wind, low temperatures and heavy snow cover. This combination has meant the country’s yaks, cattle, horses, camels, goats and sheep have gone long months without grazing adequately. The dreaded zud, as Mongolians call this phenomenon, is nothing new. In recent memory it struck three years in a row, starting in 2000—but the damage from this year’s zud is proving to be the worst in decades.

Experts warn that the next four to six weeks will see more cold weather and devastated herds, as ever greater numbers of frozen, emaciated animal carcasses dot the vast Mongolian countryside. The United Nations reckons that this year’s zud has robbed 120,000 Mongolian herders of at least half their livestock and that as many as 500,000 herders have been affected. UN agencies have allocated usd3.7m in emergency assistance to help remove animal carcasses, replace herders’ lost income and bring them health services.

According to the International Federation of Red Cross and Red Crescent Societies (IFRC), 19 of Mongolia’s 21 provinces have been afflicted and 4.5m animals—about one-tenth of the total livestock population—have perished in the past three months. The IFRC has launched an emergency appeal to provide food and other supplies, including medical treatment for conditions from frostbite to depression.

The disaster is also descending on the nation’s cities and towns, which already suffer from poverty, poor services and high rates of unemployment. Now it seems they must accommodate an influx of tens of thousands of rural migrants who have lost their herds.

Drought, cold and snow are the proximate causes of this season’s widespread misery. But weather alone is not to blame for its severity. In the 20 years since Communist rule in Mongolia ended, herding practices have changed drastically. Privatisation meant the dismantling of large collectives, and herders now find themselves missing some of the underappreciated benefits of scale—not to mention, in many cases, access to technical and management expertise of the kind that helped sustain operations through harsh winters.

According to Save the Children, another relief agency active in Mongolia, many distressed herders are advocating a return to the Soviet-style system. But even that would not set things right. The old system depended heavily on the Soviet army’s role as a reliable buyer of Mongolian animal products—as well as on direct subsidies ordered by the Politburo. Whatever the zud may bring in years to come, those days are gone for good.