NOAA National Environmental Satellite, Data, and Information Service National Climatic Data Center, U.S. Department of Commerce
NOAA Paleoclimatology Program, NCDC Paleoclimatology Branch  
Paleoclimatology Navigation Bar Bookmark and Share
NOAA National Environmental Satellite, Data, and Information Service National Oceanic and Atmospheric Administration NOAA National Climatic Data Center U.S. Department of Commerce Paleo Home Data Paleo Projects Paleo Perspectives Education and Outreach About Paleo Program Site Map
Data Access Tutorial Glossary About CTL CTL Site Map
CTL Overview white space
Today white space
1 Year white space
10 Years white space
100 Years white space
1,000 Years white space
10,000 Years white space
100,000 Years white space

white space

Climate Science:
Investigating Climatic and Environmental Processes
Weather vs. Climate
Forcing Factors

Characterizing Climate

Beginning with the daily and annual cycles and using the power of ten to view longer time scales, Climate Science provides insight into how scientists use data to study climate variability. See an overview of climate processes for general background on Earth's climate system.

Abrupt climate change from Moon Lake salinityThis graph is a reconstruction of lake salinity for Moon Lake, ND. The data (from Laird, et. al., 1996) indicates that the region was generally drier in the early part of the record than in more recent centuries, with an abrupt climate change around 1200 A.D. when the climate shifted from a pattern of regular droughts lasting decades to a wetter climate.

Because records from instruments such as rain gauges and thermometers are limited in their scope, we examine the past climate record using "paleoclimate proxies" such as tree rings and ice cores to reconstruct past climate events. Patterns can be found in many of these natural recorders such as the annual cycle which can leave annual bands in trees, ice caps and some types of coral, and longer term orbital cycles such as precession which are thought to trigger major Ice Age events.

In recent years a large array of climate related dated has been compiled and analyzed. Some questions about climate dynamics have been answered, but the research has revealed the complexity and "nonlinear" nature of many of the systems and processes, raising new questions. Moreover, there remains significant debate and in some cases disagreement in the scientific research community about the nature and implications of these dynamics. Is the El Niño-Southern Oscillation really an oscillation? What role does water vapor- an important greenhouse gas- play in increasing or decreasing global warming? Has climate triggered disease outbreaks? How do various forces that generate climate change interact with each other?

Weather vs. Climate
Radar and sunset from NOAA photo library

Although the two words are sometimes used interchangeably, there are important differences between weather and climate.

Weather's variability occurs quickly, in the period of hours and days, and while extremes between high and low temperatures or abrupt storms can occur on such small time scales, they are influenced by longer-term climatic forces.

Scientists are finding that even with as much information as they have gathered about current and past weather and climates, it is difficult to predict weather beyond an 11-14 day time horizon. Forecasting longer-term climate also proves challenging, although some scientists have a strong track record of predicting tropical storm patterns or the climatic consequences of El Niño type events some months in advance. See Future Forecasts for more.

Image of globe

Weather and climate are influenced by a variety of factors such as:
-astronomical factors such as the tilt of the Earth's axis
-the climate character of a region
-the time of year/season
-the time of day
-volcanic activity
-chemical composition of the atmosphere, including the influence of human impacts such as heat from cities, agriculture practices, and the burning of fossil fuels.


Characterizing Climate
Image of current sea surface temperature

Oceans cover over 70% of the planets surface and their ability to retain and release heat make them one of the major drivers of weather and climate. ENSO (El Niño Southern Oscillation), PDO (Pacific Decadal Oscillation), NAO (North Atlantic Oscillation) and the Thermohaline Circulation (THC) are among the ocean dynamics that may influence climate patterns. The above image is an animation of recent anomalies or irregularities in sea surface temperature (or SST) in the Pacific ocean.

Images (top to bottom) from CLIVAS, NOAA Photo Library, NGDC and CDC/NOAA.

Dividing Line
Privacy Policy information User Survey link First Gov logo Disclaimer information
Dividing Line
Downloaded Tuesday, 24-Jan-2017 04:07:01 EST
Last Updated Wednesday, 20-Aug-2008 11:22:39 EDT by
Please see the Paleoclimatology Contact Page or the NCDC Contact Page if you have questions or comments.