ARM

Tag: SGP

  • New VAP Yields Aerosol Optical Depth from Irradiance Measurements

    This plot shows spectral AOD versus time of day from the SASHE at the AMF1 Cape Cod site. The plot shows a cloudy morning (gray symbols) followed by cloud-free conditions (colored symbols in a “rainbow” pattern) with aerosol burden evolving over the course of the day. The Shortwave Array Spectroradiometer-Hemispheric (SASHE) is a ground-based instrument…

  • Rejected! Update to Langley VAP Dismisses Outliers

    An example of a clear day where most values made it through the cloud screening algorithm.A Langley plot is a regression of log (signal) versus airmass. Under appropriate conditions, the Langley regression yields values that represent the response of an instrument in absence of atmosphere (i.e., at the top of atmosphere), and these values are…

  • New Value-Added Product Provides Tropospheric Temperature Measurements

    Sample output from the RLPROFTEMP VAP showing four selected months. Results are shown for (a) January 2009, (b) April 2009, (c) July 2009, and (d) October 2009.Temperature is one of the most fundamental atmospheric state variables and is crucial to the understanding of many meteorological processes. The Raman lidars at the ARM Climate Research Facility…

  • Additional Data Added to Aerosol Optical Depth Product

    AOD at five wavelengths (top) and Angstrom exponent (bottom) at the Gan Island site on November 5, 2011.Aerosol optical depth (AOD) measures total aerosol burden in the atmosphere. The spectral dependence of AOD, typically described by the Angstrom exponent, is also an indicator of particle size. Small Angstrom exponent values (near zero) indicate presence of…

  • New Evaluation Product Estimates Aerosol Properties

    Time series of the retrieved aerosol optical depth (aod), single-scattering albedo (ssa), and asymmetry factor (asym) at 415 nm (green color) and 500 nm (red color) wavelengths for May 9, 2011. Solid black line represents a parameter describing the temporal variability of aod: parameter = 1 (variability is large) and parameter = 0 (variability is…

  • Convective Vertical Velocity Data Ready for Evaluation

    A cross-section of the atmosphere over the Billings, Oklahoma, radar wind profiler (RWP) at 22:12 UTC on May 23, 2011. The x-axis shows the location of the RWP (-14.5 km) in relation to the SGP Central Facility (0 km). The y-axis shows height above the surface. The bar on the right-hand side shows reflectivity. Contours…

  • New Evaluation Product Provides Improved Eddy Correlation Data

    This figure describes the process used to generate the QCECOR VAP. Click to enlarge.Eddy correlation flux measurement systems (ECOR) are used by ARM to provide surface turbulence flux measurements. The Quality Controlled Eddy Correlation Flux (QCECOR) value-added product (VAP) improves the ECOR data by applying the following quality control (QC) procedures: Eddy correlation corrections Determination…

  • New Radar Data Lead to New Value-Added Product

    This sample KAZR-ARSCL plot shows data from the SGP on April 26, 2011. The top image shows the ‘reflectivity_best_estimate’ field, and the lower image shows cloud base and cloud top heights for all cloud layers detected on this day.The Ka-band ARM zenith radars (KAZRs) have replaced the long-serving millimeter-wavelength cloud radars (MMCRs). As a result,…

  • New Evaluation Product Provides Thermodynamic Variables from Multiple Instruments

    INTERPSONDE output from the SGP Central Facility during the Midlatitude Continental Convective Clouds Experiment from April 26, 2011. The Interpolated Sonde (INTERPSONDE) value-added product (VAP) is an intermediate step of the MERGESONDE VAP that produces a daily file of atmospheric state variables (temperature, humidity, pressure, and winds) from radiosonde soundings, the microwave radiometer, and surface…

  • Aerosol Optical Depth Measurements Available as Value-Added Product

    These two images show data plots of cloud-screened AOD at the AMF site in China collected on a 20-second interval during daylight hours. These two days show drastically different aerosol optical depths.Aerosol optical depth (AOD) is a measure of the total aerosol burden in the atmosphere. The spectral dependence of AOD, typically described by the…