DAAC Home > Resources > News


Daymet Version 4 Data Products highlighted by NASA's Earthdata

Submitted by ORNL DAAC Staff on
Image Media
Daymet V4 Daily Precipitation
Image Media

A regional view of Daymet V4 daily total precipitation over 2 days during the time period that Hurricane Harvey made landfall in August of 2017.

A new article published on NASA's Earthdata website highlights the recent release of Daymet Version 4 and describes improvements over previous versions and plans for decreased latency.

Daymet: Daily Surface Weather Data on a 1-km Grid for North America, Version 4

Daymet Version 4's improvements in algorithm methods and sensor timing and bias result in more accurate and precise data. From the article we learn that V4 "provides effective solutions to known issues with sensor and time of observation biases while taking advantage of the latest station observation datasets. For example, algorithm improvements address issues associated with bounded limits to the range of regression estimates in both temperature and precipitation, resulting in better estimations in all variables of the gridded data products. In addition, potential station input biases based on available time of observation were evaluated for both temperature and precipitation."  Daymet data users will find consistency in the V4 distributed gridded estimates of daily weather parameters for North America, Hawaii, and Puerto Rico, covering the period from 1980 to the most recent full calendar year. Due to additional funding, data for Puerto Rico is available starting in 1950.

Daymet variables include minimum and maximum temperature, precipitation, shortwave radiation, vapor pressure, snow water equivalent, and day length, in a North America Lambert Conformal Conic projection and are distributed in a standardized Climate and Forecast (CF)-compliant netCDF file format.

The Daymet project website provides a variety of access options to all Daymet data including daily data, annual and monthly climatologies, and station-level cross validation estimates.  The project page also Citation information, Publications, and Learning resources.


Thornton, M.M., R. Shrestha, Y. Wei, P.E. Thornton, S. Kao, and B.E. Wilson. 2020. Daymet: Daily Surface Weather Data on a 1-km Grid for North America, Version 4. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1840