Why is the Amazon rainforest burning?

On Monday, Canada pledged $15 million to help fight fires in the Amazon rainforest. That's on top of the $26.5 million the G7 pledged at the conclusion of this weekend's gathering in France. But why are so many of these fires ablaze in the first place? Today on Front Burner, we talk to Jake Spring. He's a Reuters correspondent based in Brazil and the host of the Foreign Correspondence podcast who has reported on the fires from up close.