This beast that they will ride is called a tidal bore, a wave that flows in from the ocean and propagates to dozens of rivers around the world. Along the Amazon, one of the strongest bore tides brings big waves that travel for miles and seem to last forever, perfect for a long ride.
Local legend has it that three mischievous children travel up the Amazon playing practical jokes. But the scientific harbinger of this curse — or gift if you’re a surfer — is that familiar force we call gravity.
During new and full moons, when the river is relatively shallow and the ocean tide is high, water flows in from the Atlantic, rather than the other way around. As river and ocean collide, the Amazon’s flow reverses and a water swell speeds upstream with incredible force.
The strongest tidal bores occur on biannual equinoxes in September and March, when the sun, moon and Earth align; their combined gravitational pull brings ocean tides to their peak. A full moon on March 23 combined with the equinox means good news for bore riders like Serginho Laus, a surfer and Pororoca pioneer. He broke records in 2003 for his 33.25-minute, 6.3-mile ride along the pororoca of the Araguari, a river in the Brazilian Amazon basin.
And while it might sound tempting for any normal surfer to book a ticket to Brazil to try and paddle into the Pororoca, Laus told the Times that the powerful wave (which can be heard approaching an hour before it arrives) should only be handled by professionals.
“You can’t go alone,” Laus said. “You need to have a crew, with boat pilots and locals that know the way of the river.”
Source: The New York Times