When I read that the soccer balls used for World Cup games have been specially designed for the climate in Brazil, that got me wondering – which climate? Brazil has many different climates. And are the players ready for a wide range of climates too?

Technically it’s winter in the Southern Hemisphere, but that doesn’t stop the heat or humidity in a place like Manaus, Brazil, at the heart of the Amazon rainforest. During Saturday’s match between England and Italy it was a sweltering 90 degrees Fahrenheit. With over 80 percent humidity, the difference between air and water was slight.

But during Sunday’s match between France and Honduras, 2,000 miles away in Porto Alegre, Brazil, the temperature on the field only got up to 73 degrees. Humidity was much lower too – still high compared to many places, but much less humid than Manaus. In the evening, temperatures were chilly enough for a sweater.

Brazil is huge, spanning about 40 degrees of latitude, and includes ten different climates. Brazilians have peppered 12 soccer stadiums for the World Cup throughout many of these climates, providing the opportunity for players to move from hot and moist stadiums like the one in Manaus to cooler and drier stadiums like the one in Porto Alegre or even a hot and dry stadium like the one in Natal.

If you are watching World Cup games and predicting which teams will win matches, might I suggest that you take into account the climate where matches are played. You can do this with a map of regional climates like the one below. The map is no soothsaying octopus, but it can provide a good first guess at what types of weather soccer players will encounter around the country. Plus, you will be the envy of all other soccer fans if you watch each game with a colorful map in hand.

The Köppen Climate Classification System divides land into different climate types based on average temperature and precipitation. This is regional climate variation. The climate varies over geography depending on factors such as distance from the equator, altitude, and proximity to a coast. All the patchiness of regional climates worldwide, averaged together, is global climate.

I doubt that showcasing regional climates was the reason for the 12 locations, but, for the weather and climate fans among us, it will be an exciting twist. A team that’s winning at temperate stadiums might be struck down when faced with a midday match in extreme heat. My hypothesis is that dehydration and heat exhaustion will be more common in matches in the blue areas on the map, which are hottest and most humid, and the orange areas, which are hot and dry. The World Cup stadiums in green areas in the south will likely have less heat-related ailments, however there’s another variable that could compromise the athletes: smog. Several of the cities in the south are more known for air pollution than hot weather.

In preparation for Saturday’s match in the hot and humid Manaus, the English and Italian teams were training for the climate. According to the LA Times, the Italian players were running on treadmills in a sauna and the British were training in thick extra layers of clothing to get used to the heat.

There will be an extra opponent on the field – climate. If you watch the matches, also watch for climate. It’s invisible, but will be making an impact. The different climates within Brazil are a wildcard in World Cup games. Any octopus could predict that.

Köppen map adapted from Alvares et al., 2013.

Further reading:

Climate Science Basics

Spark Blog at the UCAR Center for Science Education

About the Köppen Climate Classification System

World Cup Match Locations, Days, and Times

About Brazil’s Stadiums

The Science of Soccer Ball Design