Winter Heatwaves – Explained, pointwise

Introduction

In March of last year (2022), meteorologists in India issued the first heat wave warning of the year. They were anticipating an exceptionally early summer with some of India’s highest temperatures ever recorded.

But, this year, India Meteorological Agency issued the year’s first heat wave advisory in February. It stated that regions of India’s western region could reach temperatures of 98.6 degrees Fahrenheit or higher (37C). Some parts of India, on the other hand, are experiencing temperatures that are exceptional for mid-March and are at least 9 degrees above average. Experts are concerned about the exceptionally high temperatures.

Similarly, several parts of Europe witnessed an unprecedented winter heat wave at the beginning of 2023. The Washington Post report called it an “extreme event”. Experts said that temperatures increased 10 to 20 degrees Celsius above normal.

According to the report, at least seven countries recorded their hottest January weather ever. These included Poland, Denmark, the Czech Republic, the Netherlands, Belarus, Lithuania, and Latvia.

Therefore, it becomes important to understand the reason behind the winter heat wave that has become a global phenomenon this year.

What are the factors causing winter heat waves?

In India

• Weak Western Disturbances: Western disturbance is the factor that keeps the temperature in control during Feb and march. However, this year, western disturbances have been weak due to which wind is lacking moisture for adequate rainfall. It is causing dry spells over the plains and subdued rainfall or snowfall over hills
• Climate change: In terms of climate change, the Middle East is warming faster than other regions near the equator, and it is acting as a source of warm air that blows toward India.
• Anti-cyclone formation: The anticyclone is forming over the northeastern part of the Arabian Sea, which has now moved over southwest Rajasthan. Due to this anticyclone, hot and dry winds from Balochistan, South Sindh, and Thar Desert are reaching northwest India as well as Gujarat, Maharashtra, and Karnataka.
• Possibility of El Nino Year: The last three years have been La Nia years. Scientists have predicted a high likelihood that this year will be an El Nino year. It has a significant impact on weather and climate patterns and is linked to drought and poor monsoons in India. This may also contribute to a winter heat wave in India.

In Europe

• Heat dome: According to the Washington Post, the European continent is experiencing an unusually warm spell due to the creation of a heat dome over the region.

Other General Factors

• Air flowing in from the northwest rolls in over the mountains of Afghanistan and Pakistan, so some of the compression also happens on the leeward side of these mountains, entering India with a bristling warmth.
• Lapse rate – the rate at which temperatures cool from the surface to the upper atmosphere – is declining under global warming. In other words, global warming tends to warm the upper atmosphere faster than the air near the surface. This in turn means that the sinking air is warmer due to global warming, and thus produces heat waves as it sinks and compresses.

What are heat waves?

Qualitatively, heat wave is a condition of air temperature which becomes fatal to the human body when exposed. Quantitatively, it is defined based on the temperature thresholds over a region in terms of actual temperature or its departure from normal. In certain countries, it is defined in terms of the heat index based on temperature and humidity or based on the extreme percentile of the temperatures.

How heat waves are different from Heat domes?

While both are connected, they are not the same. Weather patterns with a high-pressure system aloft and sinking air at the surface are called heat domes. Whereas A heat wave is a lengthy period of extremely hot weather that can be generated by a variety of weather patterns, including heat domes, as well as other factors such as a strong ridge of high pressure or a lack of cloud cover.

What are the Implications of heat waves?

Reduced agricultural productivity: Crops, like human bodies, thrive within a fairly narrow range of temperatures. While a small temperature increase can lead some plants to produce more, heat over 90 degrees Fahrenheit leads to a sharp drop in yields for grains like wheat, chickpeas, and mustard seeds. Last year’s (2022) heat brought wheat production down by roughly 10 percent or almost 11 million metric tons. This year has already seen not just issues with wheat production, but also with chickpeas and mustard seeds — crucial Indian crops.

Low rainfall: A lack of moisture in the winds restricts the amount of winter rain and snow in certain Himalayan cities, resulting in record-breaking temperatures.

Economic consequences: Employees are less productive during hot weather, even if they work inside, while children struggle to learn in extreme heat, resulting in lower lifetime earnings which in turn hurts future economic growth. A 2018 study found that the economies of US states tend to grow at a slower pace during hot summers. “The data shows that annual growth falls 0.15 to 0.25 percentage points for every 1 degree Fahrenheit that a state’s average summer temperature was above normal.”

Energy crisis: Moreover, a coal shortage last year (2021-2022) led to a fuel crisis in India’s thermal power plants, as electricity demand for air conditioners and fans shot up alongside a recovering post-pandemic economy. One study anticipates that by 2100, greater use of air conditioning could increase residential energy consumption by 83% globally.

Health impacts: That health can suffer greatly without spring during the transition from winter to summer. The heat index, a combination of heat and humidity, is often used to convey this danger by indicating what the temperature will feel like to most people. The high humidity also reduces the amount of cooling at night. Warm nights can leave people without air conditioners unable to cool off, which increases the risk of heat illnesses and deaths. With global warming, temperatures are already higher.

Equity and justice: Not everyone experiences heat waves in the same ways and the ill effects of heat impact most heavily those in already-disadvantaged groups.

What are the strategies to deal with heat waves?

Global

• The United Farm Workers are doing everything they can to get a new national heat regulating measure passed.
• Climate activists are continuing their campaigns for the requirements of a Green New Deal, including the need that public housing be environmentally friendly, and are also continuing their efforts to halt the development of fossil fuel

India

Prior to 2015

• Prior to 2015, there was no comprehensive national strategy to combat heat waves.
• According to the NDMA, before 2015, it was mostly up to the state governments to deal with disaster risk
• Heat waves have been declared a local disaster in Chhattisgarh, Odisha, Kerala, Rajasthan, Andhra Pradesh, Maharashtra, and
• Under the rules for disaster relief in place at the national level, heat waves were not considered to be a disaster. But, state governments were authorized to spend up to 10 percent of funds under certain heads for the heat wave

After 2015

• After 2015, the natural disaster started figuring in the priority list of topmost officials in the country including the Prime Minister as chairman of the
• Following this in 2016, the NDMA drew up the first national guidelines for heat waves titled ‘Preparation of Action Plan–Prevention and Management of Heat Wave‘.
• The guidelines were twice revised, first in 2017 and then in 2019. They were enriched with recommendations for more specific actions, based on scientific inputs derived from various research papers, reports, and best practices in heat wave assessment and mapping
• Ward-level Heat Action Plans have improved cities’ and states’ capacity to manage heat stress and respond to heat wave-related
• The revisions in 2019 included a new section, ‘Built Environment’; the revisions focused on short-term, medium-term, and long-term measures for heat wave risk
• Fixing responsibility: The National Guidelines on Heat Wave spell out in a matrix format the roles and responsibilities of central and state government agencies, district administrations, local self-governments, NGOs, civil society organizations, and other stakeholders.

What should be done going ahead?

Over the years, the NDMA has also taken a host of measures that include rescheduling of working hours for outdoor workers, the creation of drinking water kiosks, the supply of water through tankers, the erection of special shelter homes, an increase in health facilities, the stocking of ORS packets at health centers and the nearest anganwadi centers, the placement of cooling systems, and construction of gaushalas with fodder banks, etc. However, there are more steps that can be take:

1. States need to compare mortality numbers to previous years to ascertain heat-related deaths, a data set that is underdeveloped in the country.
2. Awareness should be created of the symptoms of heat stroke and its consequences as also the precautions that should be taken.
3. The Medical and Health department should keep stock of ORS, IV fluids, glucose, Pot Chlor (Potassium Chloride), derma allergic creams, and other essentials in adequate quantities while it should ensure uninterrupted telephone link to all its facilities (institutions) so that people in distress could make emergency contact with them.
4. The village secretaries and other officials concerned should conduct gram sabhas and publicize the do’s and don’ts besides ensuring dependable water
5. Persons hailing from the weaker sections who suffer heat strokes should be given free treatment at government hospitals while effort should be made to rope in NGOs and other voluntary bodies to run water and butter milk supply centres.
6. The Labour department on its part should sensitise and encourage employers to shift outdoor workers’ schedules away from peak afternoon hours during heat alert.
7. Effort should be made to ensure all amenities to children appearing for examinations in addition to prioritising maintenance of power to all critical facilities like hospitals and drinking water supply
8. District collectors should prepare their district specific heat wave action
9. Fast-tracking the switch to clean energy sources is vital to dealing with the issue of the heat wave.
10. There is a need to adapt their buildings, infrastructure, and working hours to higher temperatures.
11. There are also benefits to so-called ‘urban greening’, where more trees and other vegetation can help to cool down cities and towns.