The picture used was taken by photographer Loren McIntyre, who died in 2003, meaning the image is at least 16 years old.
The rainy season runs roughly from mid-December to mid-May, the temperature is a bit cooler than the dry season which runs roughly August - November.
The truth is that Macron is afraid of the agreement between Mercosul and the European Union. He's taking advantage of the dry season here in Brazil to take advantage.
Of course illegal fires still happen and should be judged as a crime, but with the advancement of technologies in agribusiness they have decreased.