|National Solar Radiation Data Base User's Manual (1961-1990)|
Acronyms and Nomenclature
Welcome to the new National Solar Radiation Data Base. The National Solar Radiation Data Base (NSRDB) is the successor to the SOLMET/ERSATZ data base (SOLMET, Vol. 1 1978). This new data base covers a longer and more recent period (1961-1990) than the SOLMET/ERSATZ (1952-1975), uses improved measurements and an improved model for estimating solar radiation, and provides a variety of user-friendly products.
This manual provides guidance in using all data base products from the 1961-1990 NSRDB. It also acquaints you with the many features of the new data base, and provides information on how to order and use data base products. For these purposes, we have divided the manual into two main parts: Part 1, How to Use and Interpret Data Base Products; and Part 2, How the Data Base Was Produced.
Volume 2 - Final Technical Report of the data base documentation will become available in 1992. This document will describe the research and development performed in support of the data base production.
Part 1: How to Use and Interpret Data Base Products
Part 1 gives you a general overview of the NSRDB, summarizes the type of information contained in the data base, and gives information about the types of data base products you can order and the types of magnetic storage media on which these products are available. Part 1 also provides information necessary for viewing and extracting information from the magnetic media. The hourly data can be obtained in a synoptic format similar to the SOLMET and Typical Meteorological Year (TMY) formats that are familiar to many users. Hourly data are also available in the TD-3282 format. TD-3282 is the archive format used by the National Climatic Data Center (NCDC) and is similar to the TD-3280 format used for Surface Airways Hourly Data.
The statistical products prepared from the hourly data in the NSRDB also are described in Part 1. Daily statistical information is available for each month of each year and for the entire 30-year period of record (1961-1990). Hourly means and standard deviations are available for each month and year. Diurnal profiles of hourly energy can be developed from the means. The hourly data have also been binned to provide frequency distribution information.
Information on the persistence of solar radiation is provided for various levels of daily total solar radiation energy.
Extensive efforts have been made to flag the quality and uncertainty of all the hourly data in the NSRDB. Part 1 describes the format of these quality assessment flags, and provides the information necessary to interpret them. A summary of the quality statistics can be obtained as a separate product for each station.
Part 2: How the Data Base Was Produced
Part 2 begins with a brief history of solar radiation measurements in the United States, which form the basis of the NSRDB. This is followed by detailed information on how the NSRDB was produced, to help you better understand and interpret the information contained in the data base products. Part 2 contains information on the acquistion and derivation of meteorological data and describes the METSTAT (METeorological STATistical) model which was used to estimate solar radiation when measured data were not available. The upgrading of pre-1976 solar radiation data is discussed as is the calculation of uncertainty values used in the quality flags. Part 2 concludes with a discussion of the procedures used to control and monitor the production processes and to verify and validate the computer programs used to produce the NSRDB.
Several appendices are included in the back of this manual to give you additional information on using the data base. These appendices include a list of conversion factors, a detailed station listing, and a summary of the quality statistics for the data base.
1.0 Background and Overview: The National Solar Radiation Data Base (Version 1.0)
Table of Contents