Climate encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count, and numerous other meteorological elements in a given region over long periods of time. Climate can be contrasted to weather, which is the present condition of these same elements over periods up to two weeks.

The climate collections project includes data sets containing measured and modeled values for variables such as temperature, precipitation, humidity, radiation, wind velocity, and cloud cover and include station measurements as well as gridded mean values.

The ORNL DAAC Climate Collections Data archive includes 10 data products from the following categories:

• Mean Monthly Climatology
• Historical Climatology
• Atmospheric Nitrogen Deposition
• Monthly Climatology and Precipitation
• Global Nitrogen Cycles

The following Climate Collections resources are maintained by the ORNL DAAC:

• Search Regional and Global Sources for Climate Collections data
• Data Centers Offering Regional and Global Environmental Data