XPIA
Experimental Planetary Boundary Layer Instrumentation Assessment
Overview
Multiple remote sensing devices were compared to reference measurements mounted on the National Oceanic and Atmospheric Administration (NOAA) Boulder Atmospheric Observatory (BAO) near Erie, Colorado. XPIA’s primary data collection period was run for a five-week period from March 2–April 6, 2015.
Julie Lundquist
University of Colorado Boulder
Principal Investigator
Jim Wilczak
National Oceanic and Atmospheric Administration
Co-Investigator
Objective
The primary goal of this study was to evaluate and document uncertainties of wind measurements from remote sensing systems. Sampling configurations were designed to be directly usable for validating high-fidelity models of wind plant inflows and wake flow. This goal entailed quantifying the ability of remote sensing devices to measure the three-dimensional wind field in and around operating wind plants at various temporal and spatial scales. A repeated cycle of measurements was made by all participating devices, including starting at single points and virtual tower, planar, and volumetric scans, which was intended to quantify sources of uncertainty as the scan volume increased in size and complexity.
Because turbulence and temperature profiles are critical for simulations of flow in and around wind plants for wind energy forecasting and/or wind plant control optimization, XPIA aimed to quantify the uncertainty of temperature and turbulence profiles from remote sensing platforms to profiles available from soundings and tower measurements.
Instruments
This field study included three NOAA scanning Doppler lidars, scanning lidars from other institutions, two scanning Ka-band radars from Texas Tech University, several vertical profiling lidars, a radar wind profiler with Radar Analysis Support System (RASS), and one or more microwave radiometers. Data available on the DAP:
| Instrument | DAP instance | Location Description | Latitude | Longitude | Elevation |
|---|---|---|---|---|---|
| ecor | z01 | BAO Tower | 40.05003 | -105.00384 | 1584 |
| lidar | z01 | HRDL water tank | 40.409 | -104.99845 | 1602 |
| lidar | z02 | Dalek1, EHS | 40.04702 | -105.01625 | 1582 |
| lidar | z03 | Dalek2, Visitor Center | 40.04533 | -105.00572 | 1587 |
| lidar | z04 | UTD, NE pad | 40.05063 | -105.00113 | 1582 |
| lidar | z05 | UMBC, NW pad | 40.0507 | -105.00524 | 1578 |
| lidar | z06 | DOE, S pad | 40.04881 | -105.00387 | 1587 |
| mwr | z01 | CU, Visitor Center | 40.04533 | -105.00572 | 1587 |
| mwr | z02 | NOAA, Visitor Center | 40.04533 | -105.00572 | 1587 |
| mwr | z03 | UMBC, water tank | 40.409 | -104.99845 | 1602 |
| radar | z01 | TTU Ka-band, Visitor Center | 40.04533 | -105.00572 | 1587 |
| radar | z02 | TTU Ka-band, Visitor Center | 40.04533 | -105.00572 | 1587 |
| radar | z03 | NOAA 915 MHz, Visitor Center | 40.04533 | -105.00572 | 1587 |
| radar | z04 | NOAA 449 MHz, Visitor Center | 40.04533 | -105.00572 | 1587 |
| sonde | z02 | UMBC, water tank | 40.409 | -104.99845 | 1587 |
Data Status
Data are available to download with a DAP account on the web server: https://a2e.energy.gov/data.
In addition, the Bulletin of the American Meteorological Society has published the following paper: "Assessing State-of-the-Art Capabilities for Probing the Atmospheric Boundary Layer: The XPIA Field Campaign."