RIO DE JANEIRO — Fires are burning in the Amazon rain forest at one of the fastest paces in years, Brazil’s space research center said this week.

The center, the National Institute for Space Research, which monitors fires using satellite images, reported on Wednesday that it had detected 39,194 fires this year in the world’s largest rain forest, a 77 percent increase from the same period in 2018.

The fires, most of which have been set by farmers clearing their land, are raging in uninhabited areas of rain forest and intruding on populated areas in the country’s north, including the states of Rondônia and Acre.

The blazes are so large and widespread that smoke has wafted thousands of miles away to the Atlantic coast and São Paulo, the country’s most populous city, according to the World Meteorological Organization.