This handbook presents the basic scientific concepts of climate science for non-technical audiences. It is an elaboration of Climate Literacy: The Essential Principles of Climate Sciences, a set of seven principles and their underlying fundamental concepts that developed by scientists and educators. This set of principles has been reviewed and endorsed by the U.S. Climate Change Science Program. Commentary and online resources follow each principle, allowing further exploration of key climate literacy concepts. The handbook aims to promote greater climate science literacy by providing an educational framework around the Essential Principles of Climate Science.
For a version of Climate Literacy: Essential Principles of Climate Sciences without commentary, click here.
The Essential Principles of Climate Science Literacy
- Principle 1. The Sun is the primary source of energy for Earth’s climate system.
- Principle 2. Climate is regulated by complex interactions among components of the Earth system.
- Principle 3. Life on Earth depends on, is shaped by, and affects climate.
- Principle 4. Climate varies over space and time through both natural and man-made processes.
- Principle 5. Our understanding of the climate system is improved through observations, theoretical studies, and modeling
- Principle 6. Human activities are impacting the climate system.
- Principle 7. Climate change will have consequences for the Earth system and human lives
Weather The specific conditions of the atmosphere at a particular place and time, measured in terms of variables that include temperature, precipitation, cloudiness, humidity, air pressure, and wind.
Weather Forecast A prediction about the specific atmospheric conditions expected for a location in the short-term future (hours to days).
Climate The long-term average of conditions in the atmosphere, ocean, and ice sheets and sea ice described by statistics, such as means and extremes.
Climate Forecast A prediction about average or extreme climate conditions for a region in the long-term future (seasons to decades).
Climate Variability Natural changes in climate that fall within the normal range of extremes for a particular region, as measured by temperature, precipitation, and frequency of events. Drivers of climate variability include the El Niño Southern Oscillation and other phenomena.
Climate Change A significant and persistent change in the mean state of the climate or its variability. Climate change occurs in response to changes in some aspect of Earth’s environment: these include regular changes in Earth’s orbit about the sun, re-arrangement of continents through plate tectonic motions, or anthropogenic modification of the atmosphere.
Global Warming The observed increase in average temperature near the Earth’s surface and in the lowest layer of the atmosphere. In common usage, “global warming” often refers to the warming that has occurred as a result of increased emissions of greenhouse gases from human activities. Global warming is a type of climate change; it can also lead to other changes in climate conditions, such as changes in precipitation patterns.
Climate System The matter, energy, and processes involved in interactions among Earth’s atmosphere, hydrosphere, cryosphere, lithosphere, biosphere, and Earth-Sun interactions.
Likely, Very Likely, Extremely Likely, Virtually Certain These terms are used by the Intergovernmental Panel on Climate Change (IPCC) to indicate how probable it is that a predicted outcome will occur in the climate system, according to expert judgment. A result that is deemed “likely” to occur has a greater than 66% probability of occurring. A “very likely” result has a greater than 90% probability. “Extremely likely” means greater than 95% probability, and “virtually certain” means greater than 99% probability.
Mitigation Human interventions to reduce the sources of greenhouse gases or enhance the sinks that remove them from the atmosphere.
Vulnerability The degree to which physical, biological, and socio-economic systems are susceptible to and unable to cope with adverse impacts of climate change.2
Adaptation Initiatives and measures to reduce the vulnerability of natural and human systems against actual or expected climate change effects.3
Fossil fuels Energy sources such as petroleum, coal, or natural gas, which are derived from living matter that existed during a previous geologic time period.
Feedback The process through which a system is controlled, changed, or modulated in response to its own output. Positive feedback results in amplification of the system output; negative feedback reduces the output of a system.
Carbon Cycle Circulation of carbon atoms through the Earth systems as a result of photosynthetic conversion of carbon dioxide into complex organic compounds by plants, which are consumed by other organisms, and return of the carbon to the atmosphere as carbon dioxide as a result of respiration, decay of organisms, and combustion of fossil fuels.
- Temperature Trends in the Lower Atmosphere: Steps for Understanding and Reconciling Differences. Thomas R. Karl, Susan J. Hassol, Christopher D. Miller, and William L. Murray, editors, 2006. A Report by the Climate Change Science Program and the Subcommittee on Global Change Research, Washington, DC.
- “Climate Change: An Information Statement of the American Meteorological Society,” 2007
- IPCC, 2007: The Physical Science Basis: Contribution of Working Group I
- IPCC, 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II
- IPCC, 2007: Mitigation of Climate Change. Contribution of Working Group III