By Jake Spring

SAO PAULO (Reuters) -Destruction across the Amazon rainforest so far this year has slowed dramatically, down 55.8% from the same period a year ago in a major turnaround for the region vital to curbing climate change, according to an analysis provided to Reuters.

The analysis by the nonprofit Amazon Conservation's MAAP forest monitoring program offers a first look at 2023 deforestation across the nine Amazon countries. Brazil, Colombia, Peru and Bolivia all showed declining forest loss.

"These data show there still is hope for the Amazon," said Matt Finer, an ecologist and MAAP's director.

The Amazon, the world's largest rainforest, helps to curb global warming because its trees absorb huge amounts of carbon dioxide.

The drop coincides with a shift since last year to pro-conservation governments under leftist presidents in Brazil and Colombia.

Analysts credit most of the decline to stronger environmental law enforcement in Brazil - home to the majority of the forest - under President Luiz Inacio Lula da Silva, who assumed office on Jan. 1. His predecessor Jair Bolsonaro had advocated clearing rainforest land for mining, ranching and other uses.

The success at reining in deforestation will give Amazon countries more leverage to push for conservation funding at the upcoming United Nations COP28 climate summit, experts said.

Amazon old-growth forest loss fell to 9,117 square kilometers from Jan. 1 to Nov. 8, down 55.8% from the same period in 2022, according to MAAP.

That is an area about the size of Puerto Rico but still the lowest level since at least 2019, the first year more accurate rapid satellite deforestation alerts became available.

Carlos Nobre, an earth systems scientist at University of Sao Paulo and a co-founder of the Science Panel for the Amazon research collective, called the data "wonderful news."

In 2021, more than 100 countries - including many from the Amazon - pledged to stop deforestation globally by the end of the decade.

Nobre said such a large single-year decline makes him optimistic the Amazon at least can reach that target.

The MAAP analysis also drew on NASA data to estimate that the Amazon contains more than 37 billion metric tons of carbon, which would be released into the atmosphere if the forest is destroyed. That is roughly equivalent to 2.5 times the greenhouse gas emissions from all sources globally in 2022, from coal power plants to cars, according to European Union data.

That estimate is likely low as there are some holes in the data, Finer said.

The highest levels are in the southwestern Amazon in Peru and the northeast in Guyana, Suriname and parts of Brazil and Venezuela, the MAAP data shows.

Deforestation is the largest source of greenhouse gas emissions in Amazonian countries. As destruction falls, the massive decline in emissions will bolster Brazil and others headed into the upcoming United Nations COP28 climate negotiations, which begins on Thursday, Nobre said.

Brazil's Lula has led a push among its Amazonian neighbors and other rainforest countries to get rich nations to pay for woodland conservation.

"With this data, Amazonian countries will have incredible power during COP28," Nobre said.

DECLINES FROM COLOMBIA TO PERU

Brazil is home to 60% of the Amazon and accounts for the largest part of the decline.

MAAP's independent analysis showed a 59% drop in primary forest loss in Brazil, which broadly confirms the trend shown by the country's government-produced data.

Finer credited Lula's stronger enforcement of environmental laws for the decline.

Colombian destruction declined 66.5%, perhaps due to the environmental policy of President Gustavo Petro or shifting attitudes on deforestation among former guerilla fighters who control areas of the forest, Finer said. Peru's forest loss decreased by 37%.

Bolivia saw a surge in forest loss last year, ranking third highest after Brazil and the Democratic Republic of Congo, according to data from monitoring initiative Global Forest Watch.

But MAAP data shows that Bolivian forest loss fell by nearly 60%. While the country is battling massive wildfires, many of them are not in the Amazon, Finer said.

It was not immediately apparent what drove the decline in Peru and Bolivia, Finer said.

The data extends through Nov. 8, but the remainder of the year is a low period for deforestation in much of the Amazon as torrential rains hit and make it difficult for loggers to penetrate deep into the forest.

MAAP's forest loss analysis is based on data from a European Space Agency's rapid alert satellite and the finalized annual figures will be slightly higher, Finer said.

The primary forest loss is overwhelmingly from human-caused deforestation but includes some natural loss as well, such as high winds knocking down trees.

(Reporting by Jake Spring; Editing by David Gregorio)