SAO PAULO, Sept 19 (Reuters) - Alphabet unit

Google has agreed for the first time ever to purchase

nature-based carbon removal credits from a Brazilian startup,

its first engagement with carbon projects in the South American

country.

Google will buy 50,000 metric tons of carbon removal credits

by 2030 from Mombak, which purchases degraded land from farmers

and ranchers or partners with them to replant native species in

the Amazon rainforest, the firms said on Thursday.

Google, which had previously bought engineered removal

credits, follows fellow U.S. tech giant Microsoft ( MSFT ),

which last year inked a deal to buy up to 1.5 million credits

from Mombak.

The Brazilian startup and Google did not reveal terms of the

deal. In 2023, when it sold credits to McLaren Racing, Mombak

priced them at an average of more than $50 per ton.

"The vote of confidence for us and this sector in general

that comes from Google stepping into this is a really positive

signal," Mombak's Chief Technology Officer Dan Harburg said in

an interview, hoping it would trigger more deals.

The announcement comes as companies and authorities gather

this month in New York for its annual Climate Week.

Earlier this week, Facebook owner Meta agreed to

buy up to 3.9 million carbon offset credits from Brazilian

investment bank BTG Pactual's forestry arm.

Google, Microsoft ( MSFT ), Meta and Salesforce ( CRM ) are the

co-founders of the so-called Symbiosis Coalition, which pledges

to contract for up to 20 million tons of nature-based carbon

removal credits by 2030.

Carbon offsets allow companies to make up for greenhouse gas

emissions by paying for actions to cut emissions elsewhere to

meet corporate climate goals. Each credit represents a reduction

of one ton of carbon dioxide emissions.

Critics of carbon offset markets, including Greenpeace, say

they allow emitters to keep releasing greenhouse gases.