About the Data

The 2009 State of the Climate report served as a basis for the poster and this website. This report draws on data for 10 key climate indicators that all point to the same finding: the scientific evidence that our world is warming is unmistakable. More than 300 scientists from 160 research groups in 48 countries contributed to the report, which confirms that the past decade was the warmest on record and that the Earth has been growing warmer over the last 50 years.

This set of indicators was selected, as we would unambiguously expect them to increase or decrease if the world were warming. In a warming world, based upon simple physical principles we would expect some indicators to increase land surface air temperature, sea-surface temperature, marine air temperature, sea level, tropospheric temperature, ocean heat content and specific humidity.

Conversely, we would expect the following indicators to decline: snow cover, sea-ice extent, glacier mass, and stratospheric temperatures. Stratospheric temperature decline is also influenced by ozone depletion.

Click here for a 10 page summary or full supplemental package.

Download the poste. Request a printed version
How do we know the world has warmed? by J. J. Kennedy, P. W. Thorne, T. C. Peterson, R. A. Ruedy, P. A. Stott, D. E. Parker, S. A. Good, H. A. Titchner, and K. M. Willett, 2010: [in "State of the Climate in 2009"]. Bull. Amer. Meteor. Soc., 91 (7), S79-106.

Global Climate Change Impacts in the United States, U.S. Global Change Research Program. Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson, (eds.). Cambridge University Press, 2009.

Climate Literacy: The Essential Principles of Climate Sciences, U.S. Global Change Research Program/Climate Change Science Program. (2009). Washington, DC

Why it's Important to Learn about Changing Climate indicators

In the coming decades, scientists expect climate change to have an increasing impact on human and natural systems. In a warmer world, accessibility to food, water, raw materials, and energy are likely to change. To protect fragile ecosystems and to build sustainable communities that are resilient to climate change—including extreme weather and climate events—a climate-literate citizenry is essential. (USGCRP Climate Literacy, 2009.

Climate is an ideal interdisciplinary theme for lifelong learning about the scientific process and the ways in which humans affect and are affected by the Earth's systems.

Learners of all ages can use data from their own experiments, data collected by satellites and other observation systems, or records from a range of physical, chemical, biological, geographical, social, economic, and historical sources to explore the impacts of climate.

Why does Climate Science Literacy matter in a warming world?

  • Society needs citizens who understand the climate system and know how to apply that knowledge in their careers and in their engagement as active members of their communities.
  • Climate change will continue to be a significant element of public discourse. Understanding the essential principles of climate science will enable all people to assess news stories and contribute to their everyday conversations as informed citizens.
From the USGCRP Climate Literacy Guide, 2009

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