Secretary of State John Kerry has warned that inaction on climate change will have "catastrophic" and wide-ranging consequences.
He said the release of a United Nations report detailing the pervasive effects of climate change should serve as a call to action for the world's nations to curb the emission of greenhouse gases.
Intergovernmental Panel on Climate Change finds "human interference with the climate system" could lead to strains on food systems and conflicts over fresh water resources.
"Read this report and you can't deny the reality: Unless we act dramatically and quickly, science tells us our climate and our way of life are literally in jeopardy," Kerry said, referring to the United Nations's Intergovernmental Panel on Climate Change (IPCC) report.
"The clock is ticking," Kerry said. "The more we delay, the greater the threat. Let's make our political system wake up and let's make the world respond."
"Denial of the science is malpractice..There are those who say we can't afford to act. But waiting is truly unaffordable. The costs of inaction are catastrophic," he added.
The United Nations report said that if left unchecked greenhouse gas emissions may cost trillions of dollars in damage to property and ecosystems, and in bills for shoring up climate defences.
The United States and China are among the world's biggest polluters but Kerry said "no single country causes climate change, and no one country can stop it".
Kerry cautioned that water scarcity and flooding were security risks.
He said dramatic and swift action was required to tackle the threats posed by a rapidly changing climate.
Rajendra K Pachauri, chair of the Intergovernmental Panel on Climate Change (IPCC), which produced the report, told BBC News: "Even in rich countries, the impacts of climate change could lead to greater incidents of pockets of poverty, even in rich countries it could lead to impoverishment of some particular communities.
"However there is an equity issue, because some of the poorest communities in the poorest countries in the world are going to be the worst hit."
The report's authors expressed concern that most policymakers are reacting to past events triggered by climate change rather than preparing for a changing climate future.
The report highlights that the threat climate change poses to Earth's life-support system - from declines in regional food yields, freshwater shortage, damage to settlements from extreme weather events and loss of habitable, especially coastal, land, is all missing from discussions.
"The list goes on: changes in infectious disease patterns and the mental health consequences of trauma, loss, displacement and resource conflict.
"In short, human-driven climate change poses a great threat, unprecedented in type and scale, to well-being, health and perhaps even to human survival," according to the report.
Vincente Barros, a co-chair of the working group, said many of the risks stem from a lack of action.
"We live in an era of man-made climate changeIn many cases, we are not prepared for the climate-related risks that we already face," he stated.
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