Introduction

This report is the result of discussions at the CEOP Reference Site Managers Workshop (31 March and 1 April 2003 in Berlin, Germany) and at the CEOP 2nd Implementation Planning Meeting (2-4 April 2003 also in Berlin). At the Workshop and Meeting the Prototype CEOP EOP-1 Reference Site Data Set that was developed by the CEOP Data Archive (CDA) at the University Corporation for Atmospheric Research/Joint Office for Science Support (UCAR/JOSS) was discussed and several changes were suggested and approved.

This report provides detailed descriptions of the revised formats to be used by the Reference Sites when submitting data to the CDA. Included in these format specifications are the required parameters (both observed and derived), the units that are to be used for each parameter, the values to be used to represent missing values, the equations to be used when deriving parameters, and the definitions of the data flags. The metadata requirements are also described.

All Reference Sites will continue to maintain complete site documentation to be available at the CEOP Reference Site Characteristics Table. This information includes (but is not limited to) web site links, location information (latitude, longitude, elevation), maps, photos, land characterization, canopy height, and measurements (parameters, frequency, instrumentation, specifications, and exposure).

Reference Site Data Sets, Submission Schedule, and Formats

The following table includes the four 30-minute resolution data sets that each Reference Site will develop for each station that is a part of the Reference Site. Also included is the submission schedule for data collected during CEOP EOP-3 (1 October 2002 through 30 September 2003) and CEOP EOP-4 (1 October 2003 through 30 December 2004). This schedule is in accordance with the approved CEOP Reference Site Data Policy. Finally, links are provided to the detailed format descriptions that specify the formats for the data submitted by each Reference Site.

Metadata

Each data set submitted by a Reference Site MUST be accompanied by a corresponding metadata file(s) with information such as that described in the CEOP Reference Site Data Set Metadata Procedures portion of this document.

Gap Filling

There is no specified procedure within CEOP for gap filling. If the Reference Site conducts its own gap filling strategy, the appropriate CEOP-specified data flag needs to be applied when data are interpolated/estimated. The metadata file submitted by the Reference Site MUST include a description of the gap filling strategy used. The CDA will not be implementing a gap filling procedure.

Reference Site Quality Control/Quality Assurance (QC/QA)

The QC of each data set will be performed by the Reference Site prior to submission to the CDA. The Reference Site will use the CEOP-specified data flags. The metadata file submitted by the Reference Site MUST include a description of all QC/QA procedures conducted.

Reference Site Data Set File Naming Conventions and Submission to CDA

The conventions for the naming of CEOP Reference Site Data Set files to be submitted to the CDA can be found here.

The procedures for submission of Reference Site Data Sets to the CDA can be found here.

CDA Composite Formation

The CDA will create four 30-minute CEOP Composite Data Sets using the data files submitted by the Reference Sites (i.e., the Surface Meteorological and Radiation Composite, the Surface Flux Composite, the Meteorological Tower Composite, and the Soils Composite). These composites will remain in the CEOP Reference Site Data Set formats outlined above. These Composite Data Sets will be sorted by Date/Time and then by Latitude/Longitude. Completely missing records will not be included in the Composite Data Sets.

CDA Quality Assurance (QA)

To ensure the completeness and consistency of the submitted data sets, the CDA will perform a set of limit checks and conduct a limited visual examination of the final composite data sets. When a problem is discovered the CDA will contact the responsible Reference Site manager to resolve the problem.

Rawinsonde Data Sets

Each Reference Site will submit its rawinsonde data in the highest possible vertical resolution and in the "native" format to the CDA. The CDA will not be compositing the rawinsonde data due to the large differences in the temporal and vertical resolutions between the Reference Sites. The QC of the rawinsonde data is to be performed by the reference site prior to submission to the CDA. A description of any QC procedures conducted by the Reference Site MUST be included in the metadata provided by the Reference Site.

Ancillary Data Sets

All ancillary data sets (e.g., ground-based radar and lidar, wind profiler and Radio Acoustic Sounding System (RASS), ceiliometer, special measurements, etc.) will be archived by the respective Reference Site (or it's designated data center). If a request is submitted to the CDA, the CDA will contact the respective Reference Site (or data center) to obtain a copy of these data. The CDA will then maintain a copy for any future requests. This procedure relieves the Reference site (or data center) from having to fulfill multiple requests.

Ancillary data sets in their "native" format can be submitted to the CDA. However, these data must be accompanied by separate complete documentation which includes a complete description of the data format. Any of these "native" format data sets submitted to the CDA will also be made available to the community.