Interlagos tweaked to try and stop flooding
The FIA is hoping that new grooves in the Interlagos track surface will help to address issues with track flooding at Formula 1's Brazilian Grand Prix venue.
Brazil's F1 race has often been affected by rain, including last year's sodden grand prix, and poor drainage has been a regular issue.
Rain is forecast for this weekend and six corners have been worked on prior to the race in an attempt to make it easier for the cars to run in wet conditions.
The FIA has also added some new "sausage kerbs" behind the existing kerbs on the apex of Turns 2, 4, 8 and 10.
FIA race director Charlie Whiting wrote in his notes to teams: "The apex areas of Turns 2 and 12 have been resurfaced.
"Additional grooving of the track has been carried out in places where water was accumulating the most during the race last year, notably in Turns 2, 3, 12, 13, 14 and 15."
He added: "In order to ensure that the grip of the track is more consistent it has been cleaned twice with very high pressure water."
Heavy rain delayed the start of last year's race by 10 minutes and the conditions were so treacherous that Romain Grosjean crashed on the way to the grid.
Two aquaplaning incidents in the race prompted a safety car and a 35-minute red flag respectively, and when the race was restarted poor conditions prompted another red flag shortly after.