In a development that will shock absolutely no one who has ever considered cause and effect, Brazil's government announced that deforestation in the Amazon and the Cerrado savanna has fallen to record lows - just in time for a presidential election run-off where the rainforest's future is, awkwardly, a key issue.

Left-wing President Luiz Inácio Lula da Silva, who pledged to end deforestation by 2030 when he took office three years ago, will face Flavio Bolsonaro - son of his right-wing predecessor Jair Bolsonaro - in the 25 October run-off. Polls suggest a neck-and-neck race. Flavio is expected to continue his father's policies if he wins, though he has pledged to fight organised crime in the Amazon, which is a bit like promising to tidy the living room while the roof is on fire.

Satellite data shows that in the year up to July 2026, the deforestation rate fell by 41.8% in the Amazon - the biggest drop since records began in 1988. The Cerrado, Brazil's savanna region, saw a 23.8% fall. Environment Minister Joao Paulo Capobianco called the decline "absolutely stratospheric," which is technically a weather term but we'll allow it.

The Amazon rainforest - the world's largest, 60% of which sits in Brazil - is a crucial buffer in the global fight against climate change. It also absorbs vast quantities of planet-warming carbon dioxide and hosts millions of species, all of which presumably appreciate the break.

The improvement follows a marked reversal of Jair Bolsonaro's policies. During his presidency from 2019 to 2022, Bolsonaro promoted mining in indigenous lands in the Amazon while resources to protect the forest were cut, and forest clearances soared. AFP reported, citing official data, that the Amazon lost nearly 60% more forest land during those four years than in the previous four. Lula reversed those policies, tightened environmental monitoring and increased penalties for illegal logging, and deforestation hit a six-year low in his first year in office.

"Our goal is to achieve zero illegal deforestation by 2030," Lula posted on X on Friday - a sentence that, for once, is not followed by a corporate asterisk.

Marcio Astrini, executive secretary at climate advocacy group Observatorio do Clima, called it a "historic achievement" for Brazil, noting it shows that "with political will, it is possible to curb deforestation and greenhouse gas emissions" - a finding that will surprise the many governments currently testing the alternative hypothesis.

Tropical rainforests remain under increasing pressure from decades of deliberate land clearance for agriculture and logging, as well as climate change, which scientists warn can create conditions for wildfires. So the record drop is good news in the way that a fire extinguisher is good news - vital, but not a reason to cancel the fire department.