Yes. All major scientific agencies of the United States—including the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA)—agree that climate change is occurring and that humans are contributing to it. In the 2014 National Climate Assessment, the Global Change Research Program concluded that "global climate is changing and this is apparent across the United States in a wide range of observations. The global warming of the past 50 years is primarily due to human activities, predominantly the burning of fossil fuels."[1] Hundreds of independent and governmental scientific organizations have released similar statements, both in the United States and worldwide.[1][2][3] Multiple analyses of peer-reviewed science literature have repeatedly shown that more than 97 percent of scientists in the field agree that the world is unequivocally warming, and that human activity is the primary cause.[3]

This broad consensus that climate change is happening and is caused primarily by excess greenhouse gases from human activities is based on multiple lines of evidence, from basic physics to the patterns of change through the climate system (including the atmosphere, oceans, land, biosphere, and cryosphere). However, this doesn't necessarily mean that every scientist agrees on every component of the climate change problem. Scientists are still researching a number of important questions, including exactly how sensitive Earth's climate is to human emissions of various heat-trapping gases, what the consequences of warming will be in specific regions of the world, and how other future changes in oceans and clouds will affect climate change. Scientists continue to research these questions so society can be better informed about how to plan for a changing climate. However, enough certainty exists about basic causes and effects of climate change to justify taking actions that reduce risks.

» Learn more about climate change science.

» Read NASA's web page, Scientific consensus: Earth's climate is warming.