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Jennifer Colleen Mikovitz

Publications and source records attributed to Jennifer Colleen Mikovitz.

TPSAS-NF1676L-13108-DND

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David Robert Doelling↗

Toward an Integrated Product of Higher Accuracy and Longer Time Span: Improvement of the Upcoming NASA GEWEX SRB Data Release 4 over Release 3 Based on Validation Against Surface-Based Measurements

The NASA Global Energy and Water Exchanges (GEWEX) Surface Radiation Budget (SRB) is moving toward its next generation, the Release 4 Integrated Product (Rel. 4-IP), and its shortwave algorithm preliminary results as of this writing span 34 years continuously from July 1983 to June 2017 on a quasi-equal-area grid system with 44,016 gridboxes ranging from 1 longitude times 1 latitude around the Equator to 120 longitude times 1 latitude. The data are in the form of 3-hourly, 3-hourly-monthly, daily and monthly means. The Baseline Surface Radiation Network (BSRN) is a project of the Data and Assessments Panel from the GEWEX under the umbrella of the World Climate Research Programme (WCRP). Currently in the archive there are data from 67 sites located in all seven continents spanning from 1992 to the very present. The original BSRN records are at 1-, 2-, 3- or 5-minute intervals, and sophisticated quality-control procedures have been developed to eliminate erroneous records before hourly, daily and monthly means are computed. The Pacific Marine Environmental Laboratory (PMEL) arrays of buoys in the tropical oceans, TAO/TRITON (Pacific Ocean), RAMA (Indian Ocean) and PITARA (Atlantic Ocean), measure shortwave downward fluxes using pyranometers. These buoys transmit measured data to shore in real-time via the Argos satellite system. And these buoys are major components of the CLIVAR climate analysis project and the GOOS, GCOS, and GEOSS observing systems. So far there are data from 64 buoys and the earliest data start from 2000. We have extensively validated the Rel. 4-IP preliminary results against the BSRN and PMEL 3-hourly, daily and monthly means. In this paper, we will show that the new results not only temporally span 10 years longer than its predecessor, Release 3, but agree significantly better with the BSRN data over the land and PMEL data over the ocean.

Taiping Zhang↗

Assessing Uncertainties and Variability 34 Years of Surface Radiative Fluxes Using GEWEX SRB Release4-IP

The NASA/GEWEX Surface Radiation Budget (SRB) project produces 3-hrly shortwave and longwave surface and top of atmosphere radiative fluxes for the 1983-near present time period. The new Release 4 Integrated Product (IP) uses the newly recalibrated and processed ISCCP HXS product as its primary input for cloud and radiance data, replacing ISCCP DX with a ninefold increase in pixel count (10 km instead of 30 km). This first version retains a 1°x1° resolution enabling intercomparison against previous versions and other data sets such as CERES, but spans 34 years from July 1983 through June 2017 and was announced by Kummerow et al. 2019 (GEWEX News). This new IP product also uses an atmospheric temperature and moisture dataset known as nnHIRS and other parameters such as near surface and skin temperatures from SeaFlux and LandFlux data sets. In addition to the input data improvements, several important algorithm improvements have been made since Release 3. These include recalculated SW atmospheric transmissivities and reflectivities, updated ocean and snow/ice albedos, and variable total solar irradiance consistent with SORCE measurements. The LW code has been updated to improve the optical property treatment for clouds and aerosols are included in this version. Radiative treatment of ice clouds is also improved in the LW. The variable aerosol optical properties for the SW and LW are specified using a detailed aerosol history from the Max Planck Institute Aerosol Climatology (MAC). Here we present an assessment of the LW radiative fluxes and the uncertainty of those fluxes relative to the various inputs to surface SW/LW flux measurements from BSRN and PMEL buoys measurements. We review the validation of the SW and LW fluxes and then in terms of time series and then assess the products in terms of their long-term variability of the surface SW and LW net fluxes compared to multiple other data products including atmospheric reanalysis products. The comparisons of radiative estimates to observations are performed at various temporal scales and aimed at investigation of agreement at longer time averages but accessing potential change in diurnal magnitude and daily variability. Utilizing this uncertainty information, to access long-term variability of surface radiation components at selected region and global scales, considering satellite sampling/calibration “artifacts” as necessary. At the longer time scales, the net SW and net LW the TOA and surface have implications toward closure of the energy budgets at the surface, we assess these compared to other studies on energy budget closure for the same selected global and regional scales.

Paul W Stackhouse↗

Using Time Series Data Products to Support ASHRAE’s Historic and Future Climate Data Needs through NASA’s POWER Web Services

To address the data needs for resilience and sustainability of building systems within ASHRAE, the NASA Prediction of Worldwide Energy Resource (POWER) project facilitates the use of NASA Earth Science data on a long-term, global scale. Solar data from several NASA projects and meteorological data from NASA assimilation models have been reformatted and disseminated to the public via a user friendly web GIS-enabled based data portal (https://power.larc.nasa.gov) in selectable data formats, immediately amenable to key industry wide decision support tools such as EnergyPlus. Time series of potential climate conditions from downscaled climate simulations are being made available for similar statistics and formats. An emphasis is placed upon obtaining and utilizing time series data to conduct analysis of building system performance for current and planning building systems for energy savings and greenhouse gas emissions. This presentation has the learning following learning objectives for the ASHRAE community: 1) Learn how NASA POWER’s web service suite can provide supplementary solar and surface meteorological data parameters, including a discussion of uncertainty. 2) Learn how downscaled climate scenario information can be provided to evaluate potential future requirements. The presentation is part of a forum entitled, "Weather Data for Large-Scale Building Energy Modeling".

time series↗