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DOE OSTI2023

Evaluation of the Near-Surface Variables in the HRRR Weather Model Using Observations from the ARM SGP Site

Abstract The performance of version 4 of the NOAA High-Resolution Rapid Refresh (HRRR) numerical weather prediction model for near-surface variables, including wind, humidity, temperature, surface latent and sensible fluxes, and longwave and shortwave radiative fluxes, is examined over the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) region. The study evaluated the model’s bias and bias-corrected mean absolute error relative to the observations on different time scales. Forecasts of near-surface geophysical variables at five SGP sites (HRRR at 3-km scale) were found to agree well with observations, but some consistent observation–forecast differences also occurred. Sensible and latent heat fluxes are the most challenging variables to be reproduced. The diurnal cycle is the main temporal scale affecting observation–forecast differences of the near-surface variables, and almost all of the variables showed different biases throughout the diurnal cycle. Results show that the overestimation of downward shortwave and the underestimation of downward longwave radiative flux are the two major biases found in this study. The timing and magnitude of downward longwave flux, wind speed, and sensible and latent heat fluxes are also different with contributions from model representations, data assimilation limitations, and differences in scales between HRRR and SGP sites. The positive bias in downward shortwave and negative bias in longwave radiation suggests that the model is underestimating cloud fraction in the study domain. The study concludes by showing a brief comparison with version 3 of the HRRR and shows that version 4 has better performance in almost all near-surface variables. Significance Statement A correct representation of the near-surface variables is important for numerical weather prediction models. This study investigates the capability of the latest NOAA High-Resolution Rapid Refresh (HRRRv4) model in simulating the near-surface variables by comparing against the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) in situ observations. Among others, we find that the surface heat fluxes, such as sensible and latent heat fluxes, are the most difficult variables to be reproduced. This study also shows that the diurnal cycle has the dominant impact on the model’s performance, which means the majority of the outputted near-surface variables have the strong diurnal cycle in their bias errors.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2022

Investigation of Stochastic Unit Commitment to Enable Advanced Flexibility Measures for High Shares of Solar PV

As the share of solar photovoltaics (PV) in the power system increases, there is a growing need for flexibility from multiple, possibly interdependent sources to adjust to PV's variability, uncertainty, and diurnal dependence. This paper investigates how stochastic unit commitment leveraging probabilistic solar forecasts can support other flexibility measures under high solar shares. We consider two flexibility measures relevant to day-ahead scheduling: battery energy time-shifting and solar ancillary service provision. Unit commitment and economic dispatch simulations are conducted on a realistic test system based on Texas using day-ahead solar trajectories. The benefits of the two flexibility measures are pronounced when the instantaneous solar share is high, offering cost savings of 10%-20% in the spring. For a Texas-sized system, this translates to hundreds of millions of dollars in cost savings once the installed PV capacity enables instantaneous solar shares regularly exceeding 40%. Using probabilistic forecasts also greatly increases the reliability of upward reserve provision from solar PV, reducing unserved reserves by 50%-100%. Both day-ahead forecast resolution and errors can impact system reliability at high solar shares, but the stochastic formulation has significant value, mitigating reliability impacts on over-forecast days.

ancillary services↗

DOE OSTI2023

Measurements of sound propagation in Mars' lower atmosphere

Acoustics has become extraterrestrial and Mars provides a new natural laboratory for testing sound propagation models compared to those ones on Earth. Owing to the unique combination of a microphone and two sound sources, the Ingenuity helicopter and the SuperCam laser-induced sparks, the Mars 2020 Perseverance rover payload enables the in situ characterization of unique sound propagation properties of the low-pressure CO 2 -dominated Mars atmosphere. In this study, we show that atmospheric turbulence is responsible for a large variability in the sound amplitudes from laser-induced sparks. This variability follows the diurnal pattern of turbulence. In addition, acoustic measurements acquired over one Martian year reveal a variation of the sound intensity by a factor of 1.8 from a constant source due to the seasonal cycle of pressure and temperature that significantly modifies the acoustic impedance and shock-wave formation. Finally, we show that the evolution of the Ingenuity tones and laser spark amplitudes with distance is consistent with one of the existing sound absorption models, which is a key parameter for numerical simulations applied to geophysical experiments on CO 2 -rich atmospheres. Overall, these results demonstrate the potential of sound propagation to interrogate the Mars environment and will therefore help in the design of future acoustic-based experiments for Mars or other planetary atmospheres such as Venus and Titan.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2023

Techno-Economic Analysis and Optimization of a Compressed-Air Energy Storage System Integrated with a Natural Gas Combined-Cycle Plant

To address the rising electricity demand and greenhouse gas concentration in the environment, considerable effort is being carried out across the globe on installing and operating renewable energy sources. However, the renewable energy production is affected by diurnal and seasonal variability. To ensure that the electric grid remains reliable and resilient even for the high penetration of renewables into the grid, various types of energy storage systems are being investigated. In this paper, a compressed-air energy storage (CAES) system integrated with a natural gas combined-cycle (NGCC) power plant is investigated where air is extracted from the gas turbine compressor or injected back into the gas turbine combustor when it is optimal to do so. First-principles dynamic models of the NGCC plant and CAES are developed along with the development of an economic model. The dynamic optimization of the integrated system is undertaken in the Python/Pyomo platform for maximizing the net present value (NPV). NPV optimization is undertaken for 14 regions/cases considering year-long locational marginal price (LMP) data with a 1 h interval. Design variables such as the storage capacity and storage pressure, as well as the operating variables such as the power plant load, air injection rate, and air extraction rate, are optimized. Results show that the integrated CAES system has a higher NPV than the NGCC-only system for all 14 regions, thus indicating the potential deployment of the integrated system under the assumption of the availability of caverns in close proximity to the NGCC plant. The levelized cost of storage is found to be in the range of 136–145 $/MWh. Roundtrip efficiency is found to be between 74.6–82.5%. A sensitivity study with respect to LMP shows that the LMP profile has a significant impact on the extent of air injection/extraction while capital expenditure reduction has a negligible effect.

25 ENERGY STORAGE↗

DOE OSTI2020

DSCOVR/EPIC-derived global hourly and daily downward shortwave and photosynthetically active radiation data at 0.1° × 0.1° resolution

Downward shortwave radiation (SW) and photosynthetically active radiation (PAR) play crucial roles in Earth system dynamics. Spaceborne remote sensing techniques provide a unique means for mapping accurate spatiotemporally continuous SW–PAR, globally. However, any individual polar-orbiting or geostationary satellite cannot satisfy the desired high temporal resolution (sub-daily) and global coverage simultaneously, while integrating and fusing multisource data from complementary satellites/sensors is challenging because of co-registration, intercalibration, near real-time data delivery and the effects of discrepancies in orbital geometry. The Earth Polychromatic Imaging Camera (EPIC) on board the Deep Space Climate Observatory (DSCOVR), launched in February 2015, offers an unprecedented possibility to bridge the gap between high temporal resolution and global coverage and characterize the diurnal cycles of SW–PAR globally. In this study, we adopted a suite of well-validated data-driven machine-learning models to generate the first global land products of SW–PAR, from June 2015 to June 2019, based on DSCOVR/EPIC data. The derived products have high temporal resolution (hourly) and medium spatial resolution (0.1°×0.1°), and they include estimates of the direct and diffuse components of SW–PAR. We used independently widely distributed ground station data from the Baseline Surface Radiation Network (BSRN), the Surface Radiation Budget Network (SURFRAD), NOAA's Global Monitoring Division and the U.S. Department of Energy's Atmospheric System Research (ASR) program to evaluate the performance of our products, and we further analyzed and compared the spatiotemporal characteristics of the derived products with the benchmarking Clouds and the Earth's Radiant Energy System Synoptic (CERES) data. We found both the hourly and daily products to be consistent with ground-based observations (e.g., hourly and daily total SWs have low biases of -3.96 and -0.71 W m -2 and root-mean-square errors (RMSEs) of 103.50 and 35.40 W m -2 , respectively). The developed products capture the complex spatiotemporal patterns well and accurately track substantial diurnal, monthly, and seasonal variations in SW–PAR when compared to CERES data. They provide a reliable and valuable alternative for solar photovoltaic applications worldwide and can be used to improve our understanding of the diurnal and seasonal variabilities of the terrestrial water, carbon and energy fluxes at various spatial scales.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS1973

Ionospheric effects on one-way timing signals

A proposed navigation concept requires that a user measure the time-delay that satellite-emitted signals experience in traversing the distance between satellite and user. Simultaneous measurement of the propagation time from four different satellites permits the user to determine his position and clock bias if satellite ephemerides and signal propagation velocity are known. A pulse propagating through the ionosphere is slowed down somewhat, giving an apparent range that is larger than the equivalent free space range. The difference between the apparent range and the true range, or the free space velocity and the true velocity, is the quantity of interest. This quantity is directly proportional to the total electron content along the path of the propagating signal. Thus, if the total electron content is known, or is measured, a perfect correction to ranging could be performed. Faraday polarization measurements are continuously being taken at Fort Monmouth, N. J., using beacon emissions of the ATS-3 (137.35 MHz) satellite. Day-to-day variability of the diurnal variation of total electron content values is present with differences of up to 50% or more not being uncommon. In addition, superposed on the overall diurnal variation are smaller scale variations of approximately 5 to 10% of the total content which are attributed to ionospheric density irregularities.

Soicher, H.↗

NASA NTRS1983

Influence of clouds on the earth's radiation budget determined from GOES data

Estimates of the cloud radiative effects on the earth's regional and zonal radiation budgets derived from GOES data during November 1978 are presented. The diurnal cloud cover variability is shown to affect both the radiation-budget measurements and the estimation of the overall effect of clouds on the net flux. For this data set, the cloud cover causes a decrease in the net flux from the clear-sky value. Thus, the cloud albedo effect outweights the greenhouse effect of the clouds. It is found that the value of the change in the radiation balance is closely related to the amount of incident solar radiation and to the zonal distributions of low, middle, and high cloud cover.

Harrison, E. F.↗

NASA NTRS1989

Why is there a diurnal cycle of precipitation over the oceans?

Using the Colorado State University general circulation model, simulated diurnal and semidiurnal variability of precipitation has been analyzed. At least four mechanisms have been proposed to account for the observed daily oscillations of precipitations over the ocean: direct radiation convection, radiation-dynamics-convection interactions, remote influence of the continents, and atmospheric tidal forces. Results indicate that neither land-sea contrasts nor cloudiness are necessary to produce daily variations of precipitations over the oceans. Clear-sky radiative effects, cloud-radiative effects, and the remote influence of the continents all turn out to play a role.

Randall, David A.↗

NASA NTRS1990

A midlatitude interhemispheric model of the O(+) (2P) airglow emission at 7320 A

The results are reported of the first interhemispheric model of the 7320 A airglow covering mid- and low latitudes, at all longitudes. A comprehensive model of the ionosphere and thermosphere is used to compute volume emission rates as a function of altitude, latitude, longitude, and local time. Selected results are shown here to illustrate the computational capability. In particular, the diurnal and seasonal variability and interhemispheric coupling of conjugate photoelectrons are discussed. The model is particularly well suited for airglow studies, and provides a valuable tool for the comparison, interpretation, and planning of spectroscopic observations made from orbiting platforms for all significant thermospheric emissions.

Torr, Marsha R.↗

NASA NTRS1991

Atmospheric water on Mars, energy estimates for extraction

The Mars atmosphere is considered as a resource for water to support a human expedition. Information obtained from the Viking mission is used to estimate the near-surface water vapor level. The variability over the diurnal cycle is examined and periods of greatest water abundance are identified. Various methods for extracting atmospheric water are discussed including energy costs and the means for optimizing water extraction techniques.

Meyer, Tom↗

NASA NTRS1992

Mapping Mars water vapor with the Very Large Array

This paper presents the first radio measurements of Mars atmospheric water, retrieved from interferometric spectral line observations with the NRAO VLA. Large atmospheric path lengths on the limb of Mars lead to an annulus of H2O line emission which provides a measure of the diurnal and latitudinal variability of atmospheric water on Mars. The measured line shapes of the observed H2O emission yield the first direct measurements of the vertical mixing profile of H2O in the Mars atmosphere. The observations indicate a very dry Mars atmosphere in which the globally averaged water column is approximately 3 pr micron.

Clancy, R. T.↗

NASA NTRS1994

Mean motions and tidal and two-day structure and variability in the mesosphere and lower thermosphere over Hawaii

An overview of the motion field and an analysis of the tidal and 2-day wave motions observed in the mesosphere and lower thermosphere over the central Pacific from 1 October 1990 through 19 August 1992 is presented. Characteristics and interactions of motions at lower and higher frequencies will be addressed elsewhere. Wind measurements were obtained with an MF radar operating on Kauai, Hawaii (22 deg N, 160 deg W), using the partial reflection drift technique. Results presented in this paper reveal a zonal mean motion reflecting the mesopause semiannual oscillation (MSAO) observed at more equatorial latitudes from approximately January to July, coinciding with the period during which the MSAO and the annual cycle of the zonal mean wind at higher latitudes are in phase. Eastward and westward maxima are 55 m/s below 80 km and 45 m/s near 85 km during the first year, with maxima of 57 and 53 m/s during the second year and evidence of substantial interannual variability. The second MSAO cycle is greatly suppressed in the Hawaiian data due to the reversal of the correlation between this and the annual cycle at higher latitudes from approximately July to December and because the second cycle is weaker climatologically at equatorial latitudes. Significant planetary wave activity is observed during periods of mean eastward motions, and tidal and 2-day motions are found to be large and variable. The maximum diurnal tides were observed during October and November 1990, and February, March, April, July, and August of 1991 and 1992. Maximum 2-day amplitudes occurred during February, July, and August of 1991 and 1992. Significantly, the large diurnal amplitude maximum noted during November 1990 failed to appear the following year, while the February 2-day amplitude maximum declined somewhat in 1992.

Fritts, David C.↗

NASA NTRS2012

The SeaFlux Turbulent Flux Dataset Version 1.0 Documentation

Under the auspices of the World Climate Research Programme (WCRP) Global Energy and Water cycle EXperiment (GEWEX) Data and Assessment Panel (GDAP), the SeaFlux Project was created to investigate producing a high-resolution satellite-based dataset of surface turbulent fluxes over the global oceans. The most current release of the SeaFlux product is Version 1.0; this represents the initial release of turbulent surface heat fluxes, associated near-surface variables including a diurnally varying sea surface temperature.

Clayson, Carol Anne↗

NASA NTRS2015

Tropospheric Emissions: Monitoring of Pollution Overview

TEMPO is now well into its implementation phase, having passed both its Key Decision Point C and the Critical Design Review (CDR) for the instrument. The CDR for the ground systems will occur in March 2016 and the CDR for the Mission component at a later date, after the host spacecraft has been selected. TEMPO is on schedule to measure atmospheric pollution for greater North America from space using ultraviolet and visible spectroscopy. TEMPO measures from Mexico City to the Canadian oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution. TEMPO provides a tropospheric measurement suite that includes the key elements of tropospheric air pollution chemistry. Measurements are from geostationary (GEO) orbit, to capture the inherent high variability in the diurnal cycle of emissions and chemistry. The small product spatial footprint resolves pollution sources at sub-urban scale. Together, this temporal and spatial resolution improves emission inventories, monitors population exposure, and enables effective emission-control strategies. TEMPO takes advantage of a GEO host spacecraft to provide a modest cost mission that measures the spectra required to retrieve O3, NO2, SO2, H2CO, C2H2O2, H2O, aerosols, cloud parameters, and UVB radiation. TEMPO thus measures the major elements, directly or by proxy, in the tropospheric O3 chemistry cycle. Multi-spectral observations provide sensitivity to O3 in the lowermost troposphere, substantially reducing uncertainty in air quality predictions by 50 percent. TEMPO quantifies and tracks the evolution of aerosol loading. It provides near-real-time air quality products that will be made widely, publicly available. TEMPO provides much of the atmospheric measurement capability recommended for GEO-CAPE in the 2007 National Research Council Decadal Survey, Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond. Instruments from Europe (Sentinel 4) and Asia (GEMS) will form parts of a global GEO constellation for pollution monitoring later this decade, with a major focus on intercontinental pollution transport. TEMPO will launch at a prime time to be a component of this constellation.

Chance, Kelly↗

NASA NTRS2020

Implementation of Multidomain Unified Forward Operators (UFO) Within the Joint Effort for Data Assimilation Integration (JEDI): Ocean Applications

The Joint Effort for Data assimilation Integration (JEDI) is a collaborative development led by the Joint Center for Satellite Data Assimilation (JCSDA) in conjunction with NASA, NOAA and the Department of Defense (NAVY and Air Force). The (Sea-Ice Ocean and Coupled Assimilation) SOCA as one of the JCSDA projects, focuses on the application of JEDI to marine data assimilation. One of the goals of SOCA is to make use of surface-sensitive radiances to constrain sea-ice and upper ocean fields (e.g., salinity, temperature, sea-ice fraction, sea-ice temperature, etc.). The first elements toward an ocean/atmosphere coupled data assimilation capability within JEDI, with a focus on supporting and developing the assimilation of radiance observations sensitive to the ocean and atmosphere has been implemented. The direct radiance assimilation of surface sensitive microwave radiances focusing on Global Precipitation Measurement (GPM) Imager (GMI) for the SST Constraint and Soil Moisture Active Passive (SMAP) for the Sea Surface Salinity (SSS) has been the main focus. Also, in UFO the capability to calculate the cool skin layer depth and skin temperature has been implemented similar to the GEOS-5. It has been tested with GMI sea surface temperature retrievals. This is important because Satellite and in-situ observations of the Sea-Surface Temperature (SST) show high variability, including a diurnal cycle and very thin, cool skin layer in contact with the atmosphere, and Incorporating a realistic skin SST is essential for atmosphere-ocean coupled data assimilation.

Unified Forward Operators (UFO)↗

NASA NTRS2000

Magnitude, Duration, and Geographic Coherence of Interannual Anomalies of the Great Plains Low-Level Jet

The Great Plains region of the United States is characterized by some of the world's most frequent and regular occurrences of a nocturnal low-level jet (LLJ). While this southerly jet is generally confined to the lowest kilometer of the atmosphere, it may cover a substantial region of the Great Plains and reach wind speed maxima of 20 m/s or more. The temporal and spatial structure of this jet has been well captured by the GEOS-1 15-year reanalysis. The jet is most evident during the warm season, May through August. The year-to-year variability of the seasonally-averaged jet structure is small relative to its diurnal or its intraseasonal variability and is comparable in magnitude to the seasonal variability for the mean climatology. The interannual variance maximum is located to the east of both the jet maximum and the seasonal variance maximum and seems to be related to a biennial oscillation which occurs for the first six years of the reanalysis period. There is a second maximum which is free of this oscillation, which is located at the same latitude but further south in the Gulf of Mexico. Interannual anomalies seem to have a duration of about three weeks and spatial coherences about ten degrees wide. Meridional velocity anomalies for the drought year 1988 and the flood year 1993 are large, but their impacts on the hydrological cycle may be as sensitive to their eastward location as to their magnitudes.

Helfand, H. Mark↗

NASA NTRS1995

On modeling migrating solar tides

Recent updates and extensions to a steady-state two-dimensional linearized model of global-scale atmospheric waves have facilitated improved calculations of those which are subharmonics of a solar day and propagate with the apparent motion of the sun. The model improvements are briefly described and some updated predictions of the migrating solar diurnal component are highlighted. The latter represent the first numerical modeling effort to examining the seasonal variability of the migrating diurnal harmonic as it propagates into the mesosphere and lower thermosphere.

Hagan, M. E.↗

NASA NTRSDate not supplied

Detecting Hail from Space: Using a Multi-Frequency Passive-Microwave Retrieval to Analyze the Global Climatology and Diurnal Cycle of Severe Hail

Severe hail poses myriad threats to society, causing extensive damage to infrastructure and agriculture. As hail is severe, relatively infrequent, and highly localized, it is difficult to measure in-situ and if left unresolved in models and precipitation retrievals, hail can cause large errors and uncertainties. The difficulty in measuring hail in situ and the inconsistency of surface-based hail reporting drive the motivation to use spaceborne remote-sensing platforms to retrieve hail and construct climatologies in a globally uniform way. We leverage the scattering signatures of severe hail in spaceborne passive-microwave datasets paired with surface hail reports to construct a multi-frequency hail retrieval using Tropical Rainfall Measuring Mission (TRMM) microwave imager (TMI) data. Using coincident Global Precipitation Measurement (GPM) Ku-band precipitation radar, we assessed this retrieval and several others in the literature for their effectiveness and regional variability. We use this retrieval to construct global passive-microwave climatologies of severe hail using the TRMM, GPM, Advanced Microwave Scanning Radiometer for EOS (AMSR-E), and Advanced Microwave Scanning Radiometer 2 (AMSR2) sensors and extend into the pre-TRMM era to the Special Sensor Microwave Imager/Sounder (SSMI/(S)) data. We also leverage the sensors in inclined orbits to assess the diurnal variability of severe hail globally and the effect the diurnal cycle has on the detection of hail by sensors in sun-synchronous orbit. The goal is to construct a robust, multi-decade multi-satellite climatology of hail. As part of the NASA Disasters Applied Sciences program, we assess these climatologies against other satellite severe weather datasets and use these climatologies in collaboration with stakeholders and end-users to help them assess risk, and improve the prediction, preparation, and response to severe storms around the world.

Sarah D Bang↗