The summer of 2021 will mark a turning point in the way heat is perceived by the public and communicated by experts. For the first time in 167 years of history, the UK Met Office has issued an orange warning of extreme heat for much of Wales and parts of southern, central and western England, where temperatures are expected to reach 33 ° C in places.
It’s an exciting time to be a heat researcher. I’ve spent a lot of time so far explaining to people that heat is an invisible killer that can affect all aspects of our lives. The Met Office’s new heat warning service, if well communicated, could improve the public’s often risky relationship with heat and save lives.
The Met Office was spurred on by the deaths of nearly 2,500 people in three heat waves in the UK in the summer of 2020 to change the way it forecasts hot weather. This is the highest number of heat-related deaths since the August 2003 heatwave in Europe.
So far, heat warnings for England have been issued as part of the heat health plan funded by Public Health England. These warnings are only communicated to people working in the health sector, in order to protect vulnerable people.
This system has a lot of flaws. For example, his definition of vulnerability does not cover everyone, as vulnerability is something that changes for all of us at different times in our lives. This is especially true for those who live alone or have a mental health problem and tend to go unnoticed. Many vulnerable people do not consider themselves at risk.
Extreme heat forecast
For now, the Met Office continues to only use temperature to indicate an extreme heat warning, while relative humidity, wind speed, and the amount of sun we receive all influence extreme heat levels. A warning is triggered when a part of the UK is expected to have a 70% chance of exceeding a heat threshold, defined by the average summer climate of each region of the UK, for two consecutive days and one night in between.
Here is the confusing part. This definition of an extreme heat event is different from the scientific definition of a heat wave originally established by the Met Office: when conditions are above average for three consecutive days and two nights in between. Overhaul is important because extreme heat affects health before it has been long enough or hot enough for the conditions to be classified as a heat wave.
How to beat the heat
If your area is prone to an extreme heat warning, don’t panic. There are many ways to avoid heat stress, which can cause lethargy, diarrhea, and headaches. Please see a doctor if necessary with NHS 111 or your GP and call 999 in an emergency.
Keep calm. If you are indoors, try bathing your feet in cold water or taking a shower. If you have a garden, wading pools are a good way to cool off. If you are an experienced swimmer and want to swim outdoors, do not go alone and be sure to submerge yourself slowly in the water, in a shallow area. Cold shock from jumping into deep water is a very serious risk – so far six people have drowned in 2021 because of it.
Stay hydrated. Humans are mostly water and we lose a lot of it in heat waves through sweat. Drink more often than usual, even when you are not thirsty. If you don’t like water, squash is good for replenishing the minerals your body needs. When enjoying alcohol or drinks that contain caffeine, be sure to keep drinking water as well.
Cool your house. Close the curtains and open the windows on the side not exposed to the sun. If you have a kitchen extractor fan, turn it on. If you live in an apartment building and feel comfortable doing so, leave your front door open. All of this helps keep the air circulating in your home.
Be sensitive to heat. Pay attention to people over 65, pregnant women, children under five, and people with health problems. These groups are all more vulnerable to heat. You should also avoid being in direct sunlight between 12 p.m. and 3 p.m. when the sun is strongest.
Be aware of the other risks. Sunburn and high levels of air pollution are both more likely during heat waves. There are also non-health risks, such as train signaling failures that can disrupt daily life.
Heat in a changing climate
Heat waves are becoming more frequent, longer and more intense due to climate change. Extreme heat warnings will be an important part of adapting to climate change. But it is only when forecasts are combined with adaptation measures, led by the government and communicated effectively through official channels, that this risk will be addressed.
International heat waves need more research funding and better communication. Extreme weather events such as flooding have been the subject of extensive studies and warnings for over 30 years. The Met Office’s extreme heat warning system gives hope that soon the heat will be treated more seriously.
Author: Chloe Brimicombe – PhD Student in Climate Change and Health, University of Reading