Ahead of today's opening practice session, the final FP1 of 2012, the air temperature is 22 degrees C, while the track temperature is 31 degrees. It is bright and sunny.

In the build-up to the session Sauber has confirmed that Esteban Gutierrez joins the team at the expense of Kamui Kobayashi, while Charles Pic leaves Marussia for Caterham on a "multi-year deal".

Only two reserve drivers are on duty today, Valtteri Bottas replacing Bruno Senna, no doubt as a precursor to 2013, while Giedo van der Garde is in Heikki Kovalainen's Caterham.

In the Ferrari garage Fernando Alonso looks unusually happy, his team all wishing him good luck. Along the pitlane, Lewis Hamilton sports a 'thank you McLaren' decal on his helmet.

Indeed, almost everyone is sporting a new lid this weekend, Michael Schumacher's sporting the message: 'Life is about passions. Thanks for sharing mine'.

The lights go green and di Resta leads Vergne and Ricciardo on to the track, followed by Grosjean, Kobayashi, Bottas and Perez.

Among the first out is Massa who is running the 2013 experimental tyres, two sets of which have been provided to each driver by Pirelli today. Indeed, a number of drivers are running them, Hulkenberg, Glock, Webber and Perez among the exceptions sticking with the 2012-spec.

Bottas is the first driver to post a time, the Finn crossing the line at 1:21.218. Perez subsequently raises the bar with a 17.750, the Mexican, who replaces Hamilton at McLaren next tear, goes on to post a 15.869.

Glock posts a 19.204, Marussia desperate to hold on to tenth in the final standings, the difference between that and eleventh being worth many millions of dollars in prize money.

As Schumacher goes second (17.698), Hamilton goes quickest in the first two sectors, finally crossing the line at a nifty 14.374.

That said, it's hard to compare time today whit with drivers running 2012 and 2013 spec tyres.

McLaren takes a leaf out of Red Bull's book, crew members placing themselves in front of the TV cameras as adjustments are made to Button's car. The Englishman's McLaren one of many carrying a massive amount of sensors as the teams gather as much data as possible going into the winter.

As Hamilton improves to 14.131, he complains that his tyres are overheating after just a few laps. He is running the 2013 prototype rubber.

Vettel's first flying lap sees the German go third (15.909), ahead of Maldonado, Van der Garde, Ricciardo and Vergne. Next time around the world champion improves to second with a 14.443. Alonso watches the German's progress from the back of the Ferrari garage, shades on and looking unusually cool. Out side the garage an enormous pack of photographers have their lenses trained on the Spaniard.

Button goes third on his first flying lap, the Englishman just 0.374s off the pace of his teammate. Elsewhere, Raikkonen finally leaves the pits, the Finn running a new wing today.

Vettel improves to within 0.034s of Hamilton as Alonso finally climbs into his car, overlooked by a picture of team founder Enzo Ferrari.

At 56:00, with Kobayashi, Raikkonen, Webber, de la Rosa, Karthikeyan and Alonso yet to post a time, the world championship hopeful leaves the Ferrari garage.

On his first lap Alonso posts 18.029, while di Resta goes fifth having gone quickest in S3. Webber posts 15.134 to go sixth.

As Alonso improves to fourth (14.605), in the Lotus garage a Renault crew member is changing the spark plugs on Raikkonen's car. Hamilton complains about his tyres overheating again.

At half time, it's: Hamilton, Vettel, Button, Alonso, Massa, Grosjean, di Resta, Webber, Maldonado and Kobayashi. Raikkonen and the HRT duo still to post times.

Maldonado runs wide at T4 while Glock does the same at T1, the grass having been concreted over and painted means that the Senna Esses are much like so many other corners these days. In the old days if it was wet there your session was over, today you are able to simply carry on.

T4 is catching out a lot of drivers today, Perez being the latest, the Mexican having lost track time this morning with a telemetry problem. Sauber has also changed the brake material on Kobayashi's car.