Competition between Radiative Power and Dissipation Power in the Refrigeration Process in Oxide Multifilms

This study describes the development of a prototype bi-spectral microbolometer sensor system designed explicitly for radiometric measurement and characterization of wildfire mid- and long-wave infrared radiances. The system is tested experimentally over moderate-scale experimental burns coincident with FLIR reference imagery. Statistical comparison of the fire radiative power (FRP; W) retrievals suggest that this novel system is highly reliable for use in collecting radiometric measurements of biomass burning. As such, this study provides clear experimental evidence that mid-wave infrared microbolometers are capable of collecting FRP measurements. Furthermore, given the low resource nature of this detector type, it presents a suitable option for monitoring wildfire behaviour from low resource platforms such as unmanned aerial vehicles (UAVs) or nanosats.

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Real-Time Detection of Daytime and Night-Time Fire Hotspots from Geostationary Satellites

Remote Sensing ◽

10.3390/rs13091627 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1627

Author(s):

Chermelle B. Engel ◽

Simon D. Jones ◽

Karin J. Reinke

Keyword(s):

Real Time ◽

Infrared Imaging ◽

Night Time ◽

Clear Link ◽

Radiative Power ◽

Biogeographical Region ◽

Moderate Resolution ◽

Resolution Imaging ◽

Moderate Resolution Imaging Spectroradiometer ◽

Fire Radiative Power

This paper introduces an enhanced version of the Biogeographical Region and Individual Geostationary HHMMSS Threshold (BRIGHT) algorithm. The algorithm runs in real-time and operates over 24 h to include both daytime and night-time detections. The algorithm was executed and tested on 12 months of Himawari-8 data from 1 April 2019 to 31 March 2020, for every valid 10-min observation. The resulting hotspots were compared to those from the Visible Infrared Imaging Radiometer Suite (VIIRS) and the Moderate Resolution Imaging Spectroradiometer (MODIS). The modified BRIGHT hotspots matched with fire detections in VIIRS 96% and MODIS 95% of the time. The number of VIIRS and MODIS hotspots with matches in the coincident modified BRIGHT dataset was lower (at 33% and 46%, respectively). This paper demonstrates a clear link between the number of VIIRS and MODIS hotspots with matches and the minimum fire radiative power considered.

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Jet-gas interactions at crucial jet power for feedback

Proceedings of the International Astronomical Union ◽

10.1017/s174392131500229x ◽

2014 ◽

Vol 10 (S313) ◽

pp. 260-265

Author(s):

D. M. Worrall ◽

M. Birkinshaw

Keyword(s):

Gas Flows ◽

Rich Cluster ◽

Power Sources ◽

X Ray ◽

Wide Range ◽

Higher Power ◽

Radiative Power ◽

Gas Interactions ◽

Work Done ◽

Radio Luminosity Function

AbstractMost X-ray studies of radio-mode feedback have concentrated on locally-abundant low-power radio sources in relatively rich cluster environments. But the scaling found between mechanical and radiative power, when combined with the radio luminosity function, means that half of the heating in the local Universe is expected from higher-power sources, which lie within a factor of about three of the FRI/II transition, and these sources encounter a wide range of atmosphere properties. We summarize what is observed at FRI/II transition powers from a complete sample observed with modest Chandra exposure times. We then discuss two systems with deep Chandra data. In one we find that the work done in driving shocks exceeds that in evacuating cavities. This source also displays a remarkable jet-cloud interaction, and revealing hotspot X-ray emission. In the second we find evidence of radio-emitting plasma running along boundaries between gas of different temperature, apparently lubricating the gas flows and inhibiting heat transfer, and itself being heavily structured by the process.

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Kinetic and radiative power from optically thin accretion flows

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stx543 ◽

2017 ◽

Vol 468 (2) ◽

pp. 1398-1404 ◽

Cited By ~ 18

Author(s):

Aleksander Sądowski ◽

Massimo Gaspari

Keyword(s):

Accretion Flows ◽

Radiative Power

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Combining fire radiative power observations with the fire weather index improves the estimation of fire emissions

10.5194/acp-2017-790 ◽

2017 ◽

Cited By ~ 1

Author(s):

Francesca Di Giuseppe ◽

Samuel Rémy ◽

Florian Pappenberger ◽

Fredrik Wetterhall

Keyword(s):

Biomass Burning ◽

Atmospheric Composition ◽

Composition Analysis ◽

Fire Weather ◽

Atmospheric Conditions ◽

Weather Index ◽

Fire Weather Index ◽

Fire Emissions ◽

Radiative Power ◽

Fire Radiative Power

Abstract. The atmospheric composition analysis and forecast for the European Copernicus Atmosphere Monitoring Services (CAMS) relies on biomass burning fire emission estimates from the Global Fire Assimilation System (GFAS). GFAS converts fire radiative power (FRP) observations from MODIS satellites into smoke constituents. Missing observations are filled in using persistence where observed FRP from the previous day are progressed in time until a new observation is recorded. One of the consequences of this assumption is an overestimation of fire duration, which in turn translates into an overestimation of emissions from fires. In this study persistence is replaced by modelled predictions using the Canadian Fire Weather Index (FWI), which describes how atmospheric conditions affect the vegetation moisture content and ultimately fire duration. The skill in predicting emissions from biomass burning is improved with the new technique, which indicates that using an FWI-based model to infer emissions from FRP is better than persistence when observations are not available.

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Extreme levels of Canadian wildfire smoke in the stratosphere over central Europe on 21–22 August 2017

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-11831-2018 ◽

2018 ◽

Vol 18 (16) ◽

pp. 11831-11845 ◽

Cited By ~ 26

Author(s):

Albert Ansmann ◽

Holger Baars ◽

Alexandra Chudnovsky ◽

Ina Mattis ◽

Igor Veselovskii ◽

...

Keyword(s):

Central Europe ◽

Volcanic Eruptions ◽

Light Extinction ◽

Ozone Monitoring Instrument ◽

Wildfire Smoke ◽

The North ◽

Radiative Power ◽

Peak Mass ◽

Moderate Resolution ◽

Moderate Resolution Imaging Spectroradiometer

Abstract. Light extinction coefficients of 500 Mm−1, about 20 times higher than after the Pinatubo volcanic eruptions in 1991, were observed by European Aerosol Research Lidar Network (EARLINET) lidars in the stratosphere over central Europe on 21–22 August 2017. Pronounced smoke layers with a 1–2 km vertical extent were found 2–5 km above the local tropopause. Optically dense layers of Canadian wildfire smoke reached central Europe 10 days after their injection into the upper troposphere and lower stratosphere which was caused by rather strong pyrocumulonimbus activity over western Canada. The smoke-related aerosol optical thickness (AOT) identified by lidar was close to 1.0 at 532 nm over Leipzig during the noon hours on 22 August 2017. Smoke particles were found throughout the free troposphere (AOT of 0.3) and in the pronounced 2 km thick stratospheric smoke layer at an altitude of 14–16 km (AOT of 0.6). The lidar observations indicated peak mass concentrations of 70–100 µg m−3 in the stratosphere. In addition to the lidar profiles, we analyzed Moderate Resolution Imaging Spectroradiometer (MODIS) fire radiative power (FRP) over Canada, and the distribution of MODIS AOT and Ozone Monitoring Instrument (OMI) aerosol index across the North Atlantic. These instruments showed a similar pattern and a clear link between the western Canadian fires and the aerosol load over Europe. In this paper, we also present Aerosol Robotic Network (AERONET) sun photometer observations, compare photometer and lidar-derived AOT, and discuss an obvious bias (the smoke AOT is too low) in the photometer observations. Finally, we compare the strength of this record-breaking smoke event (in terms of the particle extinction coefficient and AOT) with major and moderate volcanic events observed over the northern midlatitudes.

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Remote Sensing Data for Calibrated Assessment of Wildfire Emissions in Siberian Forests

Proceedings ◽

10.3390/ecrs-2-05161 ◽

2018 ◽

Vol 2 (7) ◽

pp. 348

Author(s):

Evgenii Ponomarev ◽

Eugene Shvetsov ◽

Kirill Litvintsev ◽

Irina Bezkorovaynaya ◽

Tatiana Ponomareva ◽

...

Keyword(s):

Standard Procedure ◽

Remote Sensing Data ◽

Fire Danger ◽

Variable Intensity ◽

Burned Areas ◽

Radiative Power ◽

Terra Modis ◽

Siberian Forests

This study was carried out for Siberia using Terra/Modis satellite data (2002–2016), data of ground surveys on burned areas of different ages, long-term meteorological information, and numerical simulation results. On the basis of meteorological and wildfire databases, we evaluated the probability (~18%) of an extreme fire danger scenario that was found to occur every 8 ± 3 years in different parts of the region. Next, we used Fire Radiative Power (FRP) measurements to classify the varieties of burning conditions for each wildfire in the database. The classification of the annually burned forest area was obtained in accordance with the assessments of burning intensity ranges categorized by FRP. Depending on the fire danger scenario in Siberia, 47.04 ± 13.6% of the total wildfire areas were classified as low-intensity burning, 42.46 ± 10.50% as medium-intensity fire areas, and 10.50 ± 6.90% as high-intensity. Next, we calculated the amount of combusted biomass and the direct emissions for each wildfire, taking into account the variable intensity of burning within the fire polygons. The total annual emissions were also calculated for Siberia for the last 15 years, from 2002 to 2016. The average estimate of direct carbon emission was 83 ± 21 Tg/year, which is lower than the result (112 ± 25 Tg/year) we obtained using the standard procedure.

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