PROVIDENCE — Brown University announced that it plans to cut campus greenhouse-gas emissions by 75% by 2025 and halt the university’s investments in fossil-fuel extraction companies.

President Christina Paxson on Wednesday posted a letter to the college community describing efforts to tackle what she said "may be the single most pressing problem that society faces today."

Paxson also described efforts by Brown to help improve the state’s ability to limit the impact of climate change, stop the university’s investments in fossil fuel companies, and use Brown’s leverage as an investor to encourage others to reduce greenhouse gases.

According to Brown, 90% of the university’s investments in companies that extract fossil fuels have been sold.

The remainder — which a university spokesman says amounts to less than 1% of Brown’s investment portfolio — is being sold.

lborg@providencejournal.com

(401) 277-7823

On Twitter: @lborgprojocom