A big climate announcement could come this week in Washington.
Experts are watching to see if Indian Prime Minister Narendra Modi commits to ratifying the Paris climate agreement before the end of the year. If India ratifies the deal, that will put it on the brink of going into force well ahead of the original 2020 target.
Advocates say it would be a strong signal that developing countries are serious about fighting climate change. But critics note that India has committed to very little under the Paris agreement. They say much more will be needed from India and the rest of the world to keep the planet below the 2-degree threshold that scientists consider critical to the well-being of the planet.
Modi is on a state visit to the United States, including a special address to a joint meeting of Congress and his seventh meeting with President Obama.