Olympic surfing’s debut shows that wave riders are undiscovered masters in science, including meteorology, climatology, and oceanography.

Because there are very few sports dependent on an uncontrollable variable, such as the weather, and the ocean is a literal uneven field, serious wave chasers will be atmospheric science junkies by default.

Surfers have a reputation for obsessively studying both.

Owen Wright, 31, is competing for Australia. “We don’t look at the weather and say, “Oh, it’s sunny,” when we know that (the wind) is offshore. It’s not like “Oh, it’s pouring.” It always has to do with how the surf is.

The Olympics organizers have at least three days of competition planned over the eight-day period that begins July 25. The day before, surf competitions are decided based on weather forecast, wave height, wind direction and temperature.

Kurt Korte is the official Olympic surfing forecaster and lead forecaster for Surfline.

However, the numbers only provide so much information. When evaluating the potential of the ocean, meteorological data is only one part of the equation. This can be a factor in determining what the ocean might deliver.

Waves are formed by how the ocean’s bottom contours and the swells interact. This is called the break. Sandbars are what cause beach breaks, such as the Olympic site at Tsurigasaki Beach. These can shift over time and be affected by storms.

Competitive surfing is simply about choosing the right wave and making the most of the ocean’s resources. For the best chance of riding a wave, surfers must be prepared and keep an eye on the waves.

“How often do the waves come in?” What is the number of waves in a set? Richard Schmidt, a former pro surfer and now a surf school owner in Santa Cruz, California, said, “Which wave of the set has the best wave?” The first wave will be choppy, but the second and the third waves are more fun because the tops are groomed by the first wave. You can see the waves and figure out the best waves.

Surfline, a U.S.-based service for forecasting surf conditions, played a key role in the International Surfing Association’s decision that the sport would make its Olympic debut at Tsurigasaki beach 90 miles east from Tokyo. Surfline has been monitoring the local conditions since 2015. It is forecasting large waves in the early days of competition due to a brewing storm.