Cold Wave

A cold wave is a period of marked and unusual cold weather characterized by a sharp and significant drop in air temperature near the surface (maximum, minimum and daily average) over a large area and persisting below certain thresholds for at least two consecutive days during the cold season (WMO, 2020).

The World Meteorological Organization guidelines on the definition and monitoring of extreme weather and climate events advise the following (WMO, 2020):

Index: Daily values of Tmax, Tmin, and /or average temperature. Another index could be computed using temperature change in the 24 hours prior to the onset of the event.
Threshold: Determined based on historical values of the index.
Temporal: Station-level information on starting date, ending date, and duration of the event. Persistence of conditions for a cold wave are two days.
Spatial: Calculate the area affected, by providing the percentage of stations where the threshold was surpassed; locate the coordinates of the impacted stations and the center with the highest/lowest values of the indices; and optional, but recommended if resources are available, to use a geographical information system (GIS) to calculate the area affected by the event, the magnitude, and severity.

This hazard category also includes Dzud which is a cold-season disaster in which anomalous climatic (i.e., heavy snow and severe cold) and/or land-surface (snow/ ice cover and lack of pasture) conditions lead to reduced accessibility and/or availability of forage/pastures, and ultimately to high livestock mortality during winter–spring. This page also contains content on Blizzard which is a severe snow storm characterised by poor visibility, usually occurring at high-latitude and in mountainous regions.

Vulnerability

Human health impacts from cold waves include mortality from ischaemic heart disease and cerebrovascular disease both of which increase in cold weather.

Living in a cold bouse can affect health at any age, not just in old age, for a variety of reasons. Although the extra deaths in elderly people are caused mainly by cardiovascular and respiratory disease, far greater numbers have minor ailments that lead to a huge burden of disease, costs to the health system, and misery.

Compared with those who live in a warmer house, respiratory problems are roughly doubled in childre, arthrities and rheumatism increase, and mental hearlth can be impaired at any age. Adolescents who live in a cold house have a five-fold increaser risk of multiple health problems (Dear and McMichael, 2011).

Risk reduction measures

To reduce impacts related to cold waves, countries have used national alerting parameters for cold wave warning or cold weather plans which help prevent major avoidable effects on health (HIP, 2021).

Latest Cold Wave additions in the Knowledge Base

Documents and publications

20 April 2023

Excess mortality attributed to heat and cold: a health impact assessment study in 854 cities in Europe

In this study, the researchers did a comprehensive mortality impact assessment due to heat and cold in European urban areas, considering geographical differences and age-specific risks.

Research briefs

15 April 2023

More heat waves and fewer cold waves are the new normal in India

A study led by Aninda Bhattacharya used daily maximum temperature and minimum temperature data from 1970 to 2019 to investigate the trend in the frequency of occurrence of days with anomalously high temperature and days with anomalously low temperature

University of Hyderabad

Update

24 February 2023

After a series of winter storms, regulators approve new standards for power plants

Standards adopted by FERC include freeze protection steps, better cold weather preparedness plans and requirements to identify freeze-prone equipment

Idaho Capital Sun

Update

14 February 2023

For disaster-hit Afghans, a brutally cold winter and shrinking aid

On a remote hillside in Afghanistan’s Logar province, the tents of some 300 families stretch across the snow-covered ground. This makeshift village has stood here since last July, when unusually strong floodwaters destroyed hundreds of nearby homes.

The New Humanitarian

Update

10 February 2023

Two years after its historic deep freeze, Texas is increasingly vulnerable to cold snaps – and there are more solutions than just building power plants

Texans like to think of their state as the energy capital of the world. But in mid-February 2021, the energy state ran short of energy.

Conversation Media Group, the

Update

2 February 2023

Texas’ tech capital again fumbles digital communication amid a power crisis

As tens of thousands of households and businesses face a third day in the dark, Austin leaders say they will improve emergency communications. But residents and critics have little patience for bungled warnings.

The Texas Tribune

Update

1 February 2023

How is climate change affecting winter storms in the US?

With extreme winter weather breaking out across the USA this week, a question in many people’s minds is—how is climate change affecting winter storms? Chat about it with Dr. Jennifer Francis, Scientist with the Woodwell Climate Research Center.

Union of Concerned Scientists

Update

29 January 2023

Inside Japan's snowy nightmare

The country is set to experience more frequent and heavier snowstorms, and as the death toll rises, it becomes clear that its snow adaptation tactics must change.

Fairplanet