Summer 2023 Review: Increasingly Polymorphous Summers

January 22, 2024
Heatwave in the summer of 2023 in France, here in Paris

The year 2023 was marked by one of the hottest summers in recent years. Unprecedented record temperatures all over the world. Despite an impression of gloomy weather in some countries such as France, the trend of increasingly hot summer is confirmed. The risk period has increased to 4 to 5 months in temperate climates and 7 to 8 months in subtropical climates. Let’s review in more details.

Record temperatures: a long summer in Europe

In Europe, the summer of 2023 was characterized by:

  • THI (Temperature and Humidity Index) in July and August globally in the average of previous years or even below in some countries such as France
  • A lengthening of the periods of heat stress before and after these two months, especially in June, September and October

READ MORE. What is the THI?

Changes and records in Asia and Latin America

In Asia, 2023 was marked by a more intense hot season. For example, an analysis of weather data shows, in Vietnam, an average increase of 2 days per month with a THI indicating heat stress (THI >71).

In Latin America, summer is underway, but it has already been preceded by heat waves in some countries.  This was the case in spring with a record temperature of 39°C – and a temperature of 58°C considering the humidity – in Rio de Janeiro in November. The period from September to November 2023 was the hottest on record.

The number of days with heat stress increases in Vietnam

READ MORE. Discover the Thermotool application which allows you to anticipate THI variations over 5 days

To download the ThermoTool mobile application on the stores: App Store (iOS) and Play Store (Android).

In conclusion, the summer of 2023 is revealing unprecedented climate trends, underlining the urgent need to take action in the face of global environmental change.