Cold wave / dzud

Extreme winter cold  can cause death and injury to people, as well as to livestock and wildlife, through direct exposure to cold temperatures, impacts on vegetation, and impacts on the built environment and infrastructure which can depend on elements that become brittle and lose function in cold temperatures.

The impacts of cold weather may often be exacerbated by heavy and persistent snow, which may limit the forage available to grazing animals. In Mongolia the term dzud is used to describe the combination of deep snow and severe cold which reduces availability of forage for livestock and can lead to high livestock mortality.  In situations where socio- and economic vulnerability is high, dzud can have a significant impact on household well‐being as well as local and national economies.


Exposure to cold temperatures, whether indoors or outdoors, can cause serious or life-threatening health problems. While infants, the elderly, and vulnerable populations are particularly at risk, anyone can be affected. To keep you and your family safe, familiarize yourself on how to prevent cold-related health problems and what to do if a cold-wave emergency occurs.

  • Familiarize yourself with who initiates cold weather warnings and where the information will be posted.
  • Make a cold weather kit for you home. In addition to the standard basic home emergency kit, include food that needs no cooking and refrigeration, water, blankets, rock salt, and an alternate, safe way to heat your home during a possible power failure.
  • If you use a fireplace or wood stove for emergency heating, have your chimney or flue inspected each year as well as invest in a multipurpose, dry-chemical fire extinguisher.
  • Install smoke detectors and a battery-operated carbon monoxide detector in your home. Test regularly and replace batteries twice yearly.
  • Insulate any water lines running along exterior walls so your water supply will be less likely to freeze. By adding weather stripping, insulation, insulated doors and storm windows, and thermal-pane windows will also aid in weather-proofing your home.
  • Remember to plan for your pets. If you have outside pets, make sure they are protected by a dry, draft-free shelter large enough to allow them to sit and lie down, but small enough to hold in their body heat. If possible, raise the floor a few inches off the ground and cover with cedar shavings or straw. Turn the shelter away from the wind and cover the doorway with waterproof burlap or heavy plastic.
  • Make sure you have materials necessary to conserve heat within your home. This includes extra towels and rags that can be used to close off unneeded rooms and prevent drafts under doors.
  • Remember that if you will be going away during the cold weather season, leave the heat on in your home and set to a temperature no lower than 13°C (55°F).
  • Prepare vehicles for a cold wave by having maintenance service as recommended by the manufacturer. Additionally, before cold wave season, have the radiator system serviced, replace windshield-wiper fluid with a wintertime mixture if available, and replace worn tires. Make a winter survival kit for your car. Remember to familiarize yourself with steps you can take if you become stranded. Items to keep in your trunk include: sand (or salt), antifreeze, windshield washer fluid, tow rope, jumper cables, fire extinguisher, and warning lights (or road flares).
  • Educate yourself to be able to detect and administer first aid in cases of hypothermia and frostbite.

[Source: CDC and American Red Cross]



Community organization can play a critical role in increasing community resilience to cold waves:

  • Contact your local Red Cross Chapter for details about community disaster education presentations that may be arranged or are available in your workplace, school, or community organization.
    • Local community-based disaster management organizations may consider effectively disseminating information and conducting outreach efforts to everyone, including those most vulnerable, in anticipation of cold weather seasons.
  • By staying up-to-date on cold weather-related events, hospitals may prepare for an increase of admissions of victims of frostbite and hypothermia.
    • Outreach efforts may be used to educate citizens how to detect and administer first aid in cases of hypothermia and frostbite.
  • Promote risk reduction measures, as well as support preventative measures, so that economic activity may not be as affected.
    • Agriculture and livestock can be affected by a cold wave and the capacity to prevent and recover from such has a direct influence on the local economy and agricultural sector.
  • Help establish regualr communication between local autorities and community stakeholders about cold wave conditions, including past and future impacts it may have.


Local and National Government

At a minimum, community officials and other key stakeholders should consider the following to ensure preparedness and readiness for cold waves:

  • People may seek alternative, unfamiliar forms of heat to warm their homes. This increases the potential for fires, creating an additional hazard during periods of extreme cold.
  • Water mains may freeze or break causing water supplies to be unreliable, making firefighting more difficult.
  • Deaths due to cold waves are mostly preventable, but only if communities and local governments are adequately prepared. Those at most risk are the vulnerable populations, including poor families who cannot afford adequate clothing and shelter, as well as the elderly and children.
  • Plan for the potential to convert schools and other public buildings into shelters to keep vulnerable citizens out of the cold. Remain aware of the effects that exposure to extreme cold has on children, the elderly, as well as those already ill, and promote outreach and preparedness efforts.
  • Be aware that demand for electrical power and fuel rises dramatically during periods of extreme cold. Additionally, some metals may become brittle at low temperatures and vehicles may stall or fail. This may impact community resources and road accessibility.



Consider creating a or revising your current workplace’s Business Continuity Program.

Although periods of extreme cold cannot always be predicted far in advance, sometimes weather forecasts can provide you with several days’ notice. Listen to weather forecasts regularly, and check you emergency supplies whenever a period of extreme cold is predicted. Taking preventative action is the best defense against having to deal with extreme cold-weather conditions. Home and car preparation in advance of winter emergencies and observing safety precautions during times of extremely cold weather can reduce the risk of weather-related health problems. [Source: CDC]

While what constitutes as extreme cold differs across the globe, whenever temperatures drop below normal and the wind speed increases, serious weather-related health problems may occur. Generally, a cold wave can be characterized by a large and rapid drop in temperatures over a short period of time that have an effect on infrastructure, health, and safety.

Cold Wave: Marked cooling of the air, or the invasion of very warm air, over a large area; it usually lasts from a few days to a few weeks. This is a drop of atmospheric average temperature well above the averages of a region, with effects on human populations, crops, properties and services. [Source: ReliefWeb]

Dzud: A multiple natural disaster consisting of a summer drought resulting in inadequate pasture and production of hay, followed by very heavy winter snow, winds and lower-than-normal temperatures. Dzuds occur when the winter conditions – particularity heavy snow cover – prevent livestock from accessing pasture or from receiving adequate hay and fodder. [Source: The World Bank]