(NEW YORK) -- Secretary of State John Kerry on Sunday spoke in stark terms about the dangers of climate change and compared those who deny it is happening to people who believe the world is flat. Calling climate change "catastrophic," Kerry called on Indonesia's leaders to work on cutting greenhouse emissions. "Climate change can now be considered another weapon of mass destruction, perhaps the world's most fearsome weapon of mass destruction," he said.
This week, Britain's weather service said climate change likely played a role in the storms and extreme floods battering the country, but stopped short of saying warming directly caused the extreme storms.
The day before Kerry's speech, the U.S. and China announced they would cooperate more closely to combat climate change. To lower emissions, the countries agreed to multiple changes including reducing vehicle emissions, improving energy efficiency of buildings and other efforts.
According to the Environmental Protection Agency, China is the largest producer of greenhouse gases, followed by the U.S. and then the European Union. U.S. officials are hoping that the agreement between the two countries will encourage other countries to lower greenhouse emissions as well, especially in developing countries. Kerry said that China and the U.S. are the cause of 40 percent of the world's greenhouse gases, but that the agreement is just one step toward cutting greenhouse emissions.
Kerry called on the Indonesian leaders to work on lowering greenhouse emissions in a country vulnerable to serious storms.
"Today, I call on all of you here in Indonesia and concerned citizens around the world to demand that resolve from your leaders. Speak out," Kerry said. "Make climate change an issue that no public official can ignore another day."
Kerry cited the intense Typhoon Haiyan, which killed thousands in Indonesia, as the kind of severe storms the country can expect if climate change worsens.
Kerry also spoke out against the vocal minority of people who deny humans are affecting the climate.
"We should not allow a tiny minority of shoddy scientists and extreme ideologues to compete with scientific facts," Kerry said.
The speech comes as the Obama administration is deciding whether to approve the Keystone XL pipeline, which environmentalists strongly oppose.
The 1,179-mile pipeline would be used to transport oil from Canada to Oklahoma, and would cross the Ogallala Aquifer in South Dakota and Nebraska.
Copyright 2014 ABC News Radio