Daymet V4 provides gridded estimates of daily weather parameters for Continental North America, Hawaii, and Puerto Rico (Data for Puerto Rico is available starting in 1950). It is derived from selected meteorological station data and various supporting data sources.
Compared to the previous version, Daymet V4 provides effective solutions to known issues and further considers improvements to what were believed to be input weather station biases. Improvements include:
- Reductions in the timing bias of input reporting weather station measurements.
- Improvement to the three-dimensional regression model techniques in the core algorithm.
- A novel approach to handling high elevation temperature measurement biases.
Documentation:
- ORNL DAAC Dataset Documentation
- Dataset Documentation
- The THREDDS location for this Collection
Daymet V4提供北美大陆、夏威夷和波多黎各的每日天气参数的网格化估计（波多黎各的数据从1950年开始提供）。它是由选定的气象站数据和各种辅助数据来源得出的。
与以前的版本相比，Daymet V4对已知的问题提供了有效的解决方案，并进一步考虑改进被认为是输入气象站的偏差。改进措施包括
减少了输入报告气象站测量的时间偏差。
对核心算法中的三维回归模型技术的改进。
处理高海拔地区温度测量偏差的新方法。
文件。
ORNL DAAC数据集文档
数据集文档
该数据集的THREDDS位置
Dataset Availability
1980-01-01T00:00:00 - 2020-12-30T00:00:00
Dataset Provider
NASA ORNL DAAC at Oak Ridge National Laboratory
Collection Snippet
ee.ImageCollection("NASA/ORNL/DAYMET_V4")
Resolution
1000 meters
Bands Table
| Name | Description | Min* | Max* | Units |
| dayl | Duration of the daylight period. Based on the period of the day during which the sun is above a hypothetical flat horizon. | 0 | 86400 | seconds |
| prcp | Daily total precipitation, sum of all forms converted to water-equivalent. | 0 | 544 | mm |
| srad | Incident shortwave radiation flux density, taken as an average over the daylight period of the day. | 0 | 1051 | W/m^2 |
| swe | Snow water equivalent, the amount of water contained within the snowpack. | 0 | 13931 | kg/m^2 |
| tmax | Daily maximum 2-meter air temperature. | -60 | 60 | °C |
| tmin | Daily minimum 2-meter air temperature. | -60 | 42 | °C |
| vp | Daily average partial pressure of water vapor. | 0 | 8230 | Pa |
数据引用：
Thornton, M.M., R. Shrestha, Y. Wei, P.E. Thornton, S. Kao, and B.E. Wilson. {YEAR}. Daymet: Daily Surface Weather Data on a 1-km Grid for North America, Version 4. ORNL DAAC, Oak Ridge, Tennessee, USA
Other Citation Details - 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. doi:10.3334/ORNLDAAC/1840
代码：
var dataset = ee.ImageCollection('NASA/ORNL/DAYMET_V4') .filter(ee.Filter.date('2017-04-01', '2017-04-30')); var maximumTemperature = dataset.select('tmax'); var maximumTemperatureVis = { min: -40.0, max: 30.0, palette: ['1621A2', 'white', 'cyan', 'green', 'yellow', 'orange', 'red'], }; Map.setCenter(-110.21, 35.1, 4); Map.addLayer(maximumTemperature, maximumTemperatureVis, 'Maximum Temperature');
