Long-Term Trends in Downwelling Spectral Infrared Radiance over the U.S. Southern Great Plains

Abstract A trend analysis was applied to a 14-yr time series of downwelling spectral infrared radiance observations from the Atmospheric Emitted Radiance Interferometer (AERI) located at the Atmospheric Radiation Measurement Program (ARM) site in the U.S. Southern Great Plains. The highly accurate calibration of the AERI instrument, performed every 10 min, ensures that any statistically significant trend in the observed data over this time can be attributed to changes in the atmospheric properties and composition, and not to changes in the sensitivity or responsivity of the instrument. The measured infrared spectra, numbering more than 800 000, were classified as clear-sky, thin cloud, and thick cloud scenes using a neural network method. The AERI data record demonstrates that the downwelling infrared radiance is decreasing over this 14-yr period in the winter, summer, and autumn seasons but it is increasing in the spring; these trends are statistically significant and are primarily due to long-term change in the cloudiness above the site. The AERI data also show many statistically significant trends on annual, seasonal, and diurnal time scales, with different trend signatures identified in the separate scene classifications. Given the decadal time span of the dataset, effects from natural variability should be considered in drawing broader conclusions. Nevertheless, this dataset has high value owing to the ability to infer possible mechanisms for any trends from the observations themselves and to test the performance of climate models.

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Response of Tallgrass Prairie to Management in the U.S. Southern Great Plains: Site Descriptions, Management Practices, and Eddy Covariance Instrumentation for a Long-Term Experiment

10.1002/essoar.10501817.1 ◽

2020 ◽

Author(s):

Pradeep Wagle ◽

Prasanna Gowda ◽

Brian Northup ◽

Patrick Starks ◽

James Neel

Keyword(s):

Eddy Covariance ◽

Great Plains ◽

Tallgrass Prairie ◽

Management Practices ◽

Southern Great Plains ◽

Term Experiment ◽

Long Term Experiment ◽

The U.S

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Comparison of Vaisala radiosondes RS41 and RS92 at the ARM Southern Great Plains Site

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-8-11323-2015 ◽

2015 ◽

Vol 8 (11) ◽

pp. 11323-11368 ◽

Cited By ~ 4

Author(s):

M. P. Jensen ◽

D. Holdridge ◽

P. Survo ◽

R. Lehtinen ◽

S. Baxter ◽

...

Keyword(s):

Great Plains ◽

Measurement Accuracy ◽

Atmospheric Temperature ◽

Atmospheric Radiation ◽

Atmospheric Conditions ◽

North Central ◽

Southern Great Plains ◽

The Us ◽

Atmospheric Radiation Measurement

Abstract. In the fall of 2013, the Vaisala RS41-SG (4th generation) radiosonde was introduced as a replacement for the RS92-SGP radiosonde with improvements in measurement accuracy of profiles of atmospheric temperature, humidity and pressure. In order to help characterize these improvements, an intercomparison campaign was undertaken at the US Department of Energy's Atmospheric Radiation Measurement (ARM) Facility site in north Central Oklahoma USA. During 3–8 June 2014, a total of 20 twin-radiosonde flights were performed in a variety of atmospheric conditions representing typical midlatitude continental summertime conditions. The results suggest that the RS92 and RS41 measurements generally agree within manufacturer specified tolerances with notable exceptions when exiting liquid cloud layers where the "wet bulbing" effect is mitigated in the RS41 observations. The RS41 measurements also appear to show a smaller impact from solar heating. These results suggest that the RS41 does provide important improvements, particularly in cloudy conditions, but under most observational conditions the RS41 and RS92 measurements agree within the manufacturer specified limits and so a switch to RS41 radiosondes will have little impact on long-term observational records.

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Regional Moisture Budget and Land‐Atmosphere Coupling Over the U.S. Southern Great Plains Inferred From the ARM Long‐Term Observations

Journal of Geophysical Research Atmospheres ◽

10.1029/2019jd030585 ◽

2019 ◽

Vol 124 (17-18) ◽

pp. 10091-10108 ◽

Cited By ~ 1

Author(s):

Cheng Tao ◽

Yunyan Zhang ◽

Shuaiqi Tang ◽

Qi Tang ◽

Hsi‐Yen Ma ◽

...

Keyword(s):

Great Plains ◽

Moisture Budget ◽

Southern Great Plains ◽

The U.S

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Comparison of Vaisala radiosondes RS41 and RS92 at the ARM Southern Great Plains site

Atmospheric Measurement Techniques ◽

10.5194/amt-9-3115-2016 ◽

2016 ◽

Vol 9 (7) ◽

pp. 3115-3129 ◽

Cited By ~ 24

Author(s):

Michael P. Jensen ◽

Donna J. Holdridge ◽

Petteri Survo ◽

Raisa Lehtinen ◽

Shannon Baxter ◽

...

Keyword(s):

Great Plains ◽

Weather Forecasting ◽

Climate Modeling ◽

Atmospheric Temperature ◽

Fourth Generation ◽

Atmospheric Conditions ◽

Southern Great Plains ◽

The Us ◽

Atmospheric Radiation Measurement

Abstract. In the fall of 2013, the Vaisala RS41 (fourth generation) radiosonde was introduced as a replacement for the RS92-SGP radiosonde with improvements in measurement accuracy of profiles of atmospheric temperature, humidity, and pressure. In order to help characterize these improvements, an intercomparison campaign was undertaken at the US Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility site in north-central Oklahoma, USA. During 3–8 June 2014, a total of 20 twin-radiosonde flights were performed in a variety of atmospheric conditions representing typical midlatitude continental summertime conditions. The results show that for most of the observed conditions the RS92 and RS41 measurements agree much better than the manufacturer-specified combined uncertainties with notable exceptions when exiting liquid cloud layers where the “wet-bulbing” effect appears to be mitigated for several cases in the RS41 observations. The RS41 measurements of temperature and humidity, with applied correction algorithms, also appear to show less sensitivity to solar heating. These results suggest that the RS41 does provide important improvements, particularly in cloudy conditions. For many science applications – such as atmospheric process studies, retrieval development, and weather forecasting and climate modeling – the differences between the RS92 and RS41 measurements should have little impact. However, for long-term trend analysis and other climate applications, additional characterization of the RS41 measurements and their relation to the long-term observational records will be required.

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Long-term aerosol-mediated changes in cloud radiative forcing of deep clouds at the top and bottom of the atmosphere over the Southern Great Plains

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-4599-2014 ◽

2014 ◽

Vol 14 (4) ◽

pp. 4599-4625

Author(s):

Hongru Yan ◽

Zhanqing Li ◽

Jianping Huang ◽

Maureen Cribb ◽

Jianjun Liu

Keyword(s):

Great Plains ◽

Radiative Forcing ◽

Reanalysis Data ◽

Southern Great Plains ◽

Convective Clouds ◽

The Us ◽

Atmospheric Radiation Measurement ◽

Core Thickness ◽

Weak Wind

Abstract. Aerosols can alter the macro- and micro-physical properties of deep convective clouds (DCC) and their radiative forcing (CRF). This study presents what is arguably the first long-term estimate of the aerosol-mediated changes in CRF (AMCRF) for deep cloud systems derived from decade-long continuous ground-based and satellite observations, model simulations and reanalysis data. Measurements were made at the US Department of Energy's Atmospheric Radiation Measurement Program's Southern Great Plains (SGP) site. Satellite retrievals are from the Geostationary Operational Environmental Satellite (GOES). Increases in aerosol loading were accompanied by the thickening of DCC cores and the expansion and thinning of anvils, due presumably to the aerosol invigoration effect (AIV) and the aerosol microphysical effect (AME). Meteorological variables dictating these cloud processes were investigated. Consistent with previous findings, the AIV is most significant when the atmosphere is moist and unstable with weak wind shear. Such aerosol-mediated systematic changes in DCC core thickness and anvil size alter CRF at the top of atmosphere (TOA) and at the surface. Using extensive observations, ~300 DCC systems were identified over a 10 yr period at the SGP site (2000–2011) and analyzed. Daily mean AMCRF at the TOA and at the surface are 29.3 W m−2 and 22.2 W m−2, respectively. This net warming effect due to changes in DCC microphysics offsets the cooling resulting from the first aerosol indirect effect.

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Multiyear Evaluations of a Cloud Model Using ARM Data

Journal of the Atmospheric Sciences ◽

10.1175/2009jas2957.1 ◽

2009 ◽

Vol 66 (9) ◽

pp. 2925-2936 ◽

Cited By ~ 8

Author(s):

Peter W. Henderson ◽

Robert Pincus

Keyword(s):

Great Plains ◽

Cloud Model ◽

Southern Great Plains ◽

Thermodynamic State ◽

Temporal Averaging ◽

Atmospheric Radiation Measurement ◽

Boundary Layer Cloud ◽

Traditional Performance ◽

Probabilistic Measures

Abstract This work uses long-term lidar and radar retrievals of the vertical structure of cloud at the Atmospheric Radiation Measurement (ARM) program’s Southern Great Plains site to evaluate cloud occurrence in multiyear runs of a cloud system–resolving model in three configurations of varying resolution and sophistication. The model is nudged to remain near the observed thermodynamic state and model fields are processed to mimic the operation of the observing system. The model’s skill in predicting cloud occurrence is evaluated using both traditional performance measures that assume ergodicity and probabilistic measures that do not require temporal averaging of the observations. The model shows considerable skill in predicting cloud occurrence when its thermodynamic state is close to that observed. The overall bias in modeled cloud occurrence is relatively small in all model runs, suggesting that this field is relatively well calibrated. The Brier scores attained by all configurations also suggest considerable model skill. Greater differences in performance are found between seasons than between model configurations during the same season, despite substantial differences between the computational costs of the configurations. Several significant seasonal dependencies are identified, most notably greater conditional bias, but better timing, of boundary layer cloud in winter, and substantially less conditional bias in high cloud during summer.

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Observing Clouds in 4D with Multiview Stereophotogrammetry

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-18-0029.1 ◽

2018 ◽

Vol 99 (12) ◽

pp. 2575-2586 ◽

Cited By ~ 4

Author(s):

David M. Romps ◽

Ruşen Öktem

Keyword(s):

Great Plains ◽

Climate Models ◽

Life Cycles ◽

Digital Cameras ◽

Southern Great Plains ◽

Stereo Cameras ◽

Weather And Climate ◽

Stereo Reconstruction ◽

Shallow Clouds ◽

Atmospheric Radiation Measurement

AbstractNewly installed stereo cameras ringing the Southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) site in Oklahoma are providing a 4D gridded view of shallow clouds. Six digital cameras have been installed in pairs at a distance of 6 km from the site and with a spacing of 500 m between cameras in a pair. These pairs of cameras provide stereoscopic views of shallow clouds from all sides; when these data are combined, they allow for a complete stereo reconstruction. The result—the Clouds Optically Gridded by Stereo (COGS) product—is a 4D grid of cloudiness covering a 6 km × 6 km × 6 km cube at a spatial resolution of 50 m and a temporal resolution of 20 s. This provides a unique set of data on the sizes, lifetimes, and life cycles of shallow clouds. This type of information is critical for developing cloud macrophysical schemes for the next generation of weather and climate models.

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Long-term aerosol-mediated changes in cloud radiative forcing of deep clouds at the top and bottom of the atmosphere over the Southern Great Plains

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-7113-2014 ◽

2014 ◽

Vol 14 (14) ◽

pp. 7113-7124 ◽

Cited By ~ 26

Author(s):

Hongru Yan ◽

Zhanqing Li ◽

Jianping Huang ◽

Maureen Cribb ◽

Jianjun Liu

Keyword(s):

Great Plains ◽

Radiative Forcing ◽

Reanalysis Data ◽

Southern Great Plains ◽

Convective Clouds ◽

The Us ◽

Atmospheric Radiation Measurement ◽

Core Thickness ◽

Weak Wind

Abstract. Aerosols can alter the macro- and micro-physical properties of deep convective clouds (DCCs) and their radiative forcing (CRF). This study presents what is arguably the first long-term estimate of the aerosol-mediated changes in CRF (AMCRF) for deep cloud systems derived from decade-long continuous ground-based and satellite observations, model simulations, and reanalysis data. Measurements were made at the US Department of Energy's Atmospheric Radiation Measurement Program's Southern Great Plains (SGP) site. Satellite retrievals are from the Geostationary Operational Environmental Satellite. Increases in aerosol loading were accompanied by the thickening of DCC cores and the expansion and thinning of anvils, due presumably to the aerosol invigoration effect (AIV) and the aerosol microphysical effect. Meteorological variables dictating these cloud processes were investigated. Consistent with previous findings, the AIV is most significant when the atmosphere is moist and unstable with weak wind shear. Such aerosol-mediated systematic changes in DCC core thickness and anvil size alter CRF at the top of atmosphere (TOA) and at the surface. Using extensive observations, ~300 DCC systems were identified over a 10 years period at the SGP site (2000–2011) and analyzed. Daily mean AMCRF at the TOA and at the surface are 29.3 W m−2 and 22.2 W m−2, respectively. This net warming effect due to changes in DCC microphysics offsets the cooling resulting from the first aerosol indirect effect.

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