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The Role of Emissivity in the Detection of Arctic Night Clouds

Filomena Romano, Domenico Cimini, Saverio Nilo, Francesco Di Paola, Elisabetta Ricciardelli, Ermann Ripepi, Mariassunta Viggiano
2017 Remote Sensing  
The objective of this study is to demonstrate the crucial role played by surface emissivity in the detection of polar winter clouds and the potential improvement offered by infrared hyperspectral observations  ...  Detection of clouds over polar areas from satellite radiometric measurements in the visible and IR atmospheric window region is rather difficult because of the high albedo of snow, possible ice covered  ...  emissivity play a dominant role in the performances of the window threshold test often used in cloud detection during the night.  ... 
doi:10.3390/rs9050406 fatcat:o557llluvre7dbbndq4noasmka

Earth as an Exoplanet: I. Time variable thermal emission using spatially resolved MODIS data [article]

Jean-Noël Mettler, Sascha P. Quanz, Ravit Helled
2020 arXiv   pre-print
The complete data set comprises 15 years of thermal emission observations in the 3.66-14.40 microns range for five different locations on Earth (Amazon Rainforest, Antarctica, Arctic, Indian Ocean and  ...  Our findings suggest that (1) viewing geometry plays an important role when thermal emission data is analyzed as Earth's spectrum varies by a factor of three and more depending on the dominant surface  ...  and night-time emission of all five locations.  ... 
arXiv:2010.02589v1 fatcat:xnqrhveit5dgvmtntbppoy7zna

Polar Cloud Climatologies from ISCCP C2 and D2 Datasets

N. Hatzianastassiou, N. Cleridou, I. Vardavas
2001 Journal of Climate  
The A c differences between C2 and D2 increase toward the South Pole and, according to the D2 data, the Arctic has only about 10% high-level cloud cover compared with 45% in Antarctica, during the polar  ...  night.  ...  The ISCCP and ERBE data were obtained from the NASA Langley Research Center Atmospheric Sciences Data Center.  ... 
doi:10.1175/1520-0442(2001)014<3851:pccfic>2.0.co;2 fatcat:b7oc7btbenb47jtmdgnwinyiza

Nighttime polar cloud detection with MODIS

Yinghui Liu, Jeffrey R. Key, Richard A. Frey, Steven A. Ackerman, W.Paul Menzel
2004 Remote Sensing of Environment  
Cloud detection is the first step in studying the role of polar clouds in the global climate system with satellite data.  ...  Results show that the current MODIS cloud mask algorithm performs well in polar regions during the day but does not detect more than 40% of the cloud cover over the validation sights at night.  ...  Surface-based cloud radar and lidar data were provided through the Department of Energy Atmospheric Radiation Measurement program and the NOAA Climate Monitoring and Diagnostics Laboratory.  ... 
doi:10.1016/j.rse.2004.06.004 fatcat:wj3wkywpijfsthppfd2isd5hdm

A meandering polar jet caused the development of a Saharan cyclone and the transport of dust toward Greenland

Diana Francis, Clare Eayrs, Jean-Pierre Chaboureau, Thomas Mote, David M. Holland
2019 Advances in Science and Research  
Ice melt over this area of Greenland was detected in the brightness temperature observations.</p>  ...  The meandering polar jet was at the origin of both dust emission through cyclogenesis over Northwest Africa and poleward transport of the uplifted dust towards the Arctic, through cut-off circulation.  ...  This research was supported by the NYU Abu Dhabi Research Institute (G1204) in the UAE. We wish to thank the editor and the two reviewers for their efforts. Review statement.  ... 
doi:10.5194/asr-16-49-2019 fatcat:pf3uwil46nc4dgnke6gvl34sdy

Arctic Cloud Changes from Surface and Satellite Observations

Ryan Eastman, Stephen G. Warren
2010 Journal of Climate  
Visual cloud reports from land and ocean regions of the Arctic are analyzed for total cloud cover.  ...  During the winter months, time series of satellite-observed clouds in numerous grid boxes show variations that are strangely coherent throughout the entire Arctic.  ...  An advance version of the ocean cloud update was provided by Carole Hahn. Axel Schweiger provided TOVS data, and Jeff Key and Xuanji Wang provided updated APP-x data. We thank J.  ... 
doi:10.1175/2010jcli3544.1 fatcat:jzci3ezn7veddndf3tclfluyhq

Arctic aerosol net indirect effects on thin, mid-altitude, liquid-bearing clouds

Lauren M. Zamora, Ralph A. Kahn, Sabine Eckhardt, Allison McComiskey, Patricia Sawamura, Richard Moore, Andreas Stohl
2016 Atmospheric Chemistry and Physics Discussions  
Here, we have reduced uncertainty in current-day Arctic net aerosol indirect effects on the surface by better constraining various physical and microphysical characteristics of optically thin, liquid-containing  ...  Aerosol presence is related to reduced precipitation, cloud thickness, and radar reflectivity, and may be associated with an increased likelihood of cloud presence in the liquid phase.  ...  because aerosol emissions within and in the vicinity of the Arctic are changing, and perhaps more importantly, the major aerosol removal processes and transport pathways to the Arctic may be changing as  ... 
doi:10.5194/acp-2016-1037 fatcat:fipwt7al7bdapa3otopx23tnke

Arctic Clouds and Surface Radiation – a critical comparison of satellite retrievals and the ERA-Interim reanalysis

M. Zygmuntowska, T. Mauritsen, J. Quaas, L. Kaleschke
2012 Atmospheric Chemistry and Physics  
While passive satellite instruments have serious difficulties, detecting only half the cloudiness of the modeled clouds in the reanalysis, the active instruments are in between.  ...  Globally averaged, at the top of the atmosphere the cloud radiative effect is to cool the climate, while at the Arctic surface, clouds are thought to be warming.  ...  We acknowledge the CloudSat project for providing the CloudSat and CALIPSO data. The AVHRR were provided by the Satellite Appli-  ... 
doi:10.5194/acp-12-6667-2012 fatcat:viqvlptxxzegpfbxbk4jwua52a

Arctic clouds and surface radiation – a critical comparison of satellite retrievals and the ERA-interim reanalysis

M. Zygmuntowska, T. Mauritsen, J. Quaas, L. Kaleschke
2011 Atmospheric Chemistry and Physics Discussions  
While passive satellite instruments have serious difficulties, detecting only half the cloudiness of the modeled clouds in the reanalysis, the active instruments are in between.  ...  Globally averaged, at the top of the atmosphere the cloud radiative effect is to cool the climate, while at the Arctic surface, clouds are thought to be warming.  ...  We acknowledge the CloudSat project for providing the CloudSat and CALIPSO data. The AVHRR were provided by the Satellite Appli-  ... 
doi:10.5194/acpd-11-31495-2011 fatcat:2vjiu5qujrbvjecytr37epa25y

Differing mechanisms of new particle formation at two Arctic sites

Lisa J. Beck, Nina Sarnela, Heikki Junninen, Clara J. M. Hoppe, Olga Garmash, Federico Bianchi, Matthieu Riva, Clemence Rose, Otso Peräkylä, Daniela Wimmer, Oskari Kausiala, Tuija Jokinen (+37 others)
2020 Geophysical Research Letters  
New particle formation in the Arctic atmosphere is an important source of aerosol particles.  ...  Plain Language Summary Cloud properties are sensitive to the formation of new aerosol particles in the Arctic atmosphere, yet little is known about the chemistry and processes controlling this phenomenon  ...  Acknowledgments The authors thank logistic support by AWIPEV and the staff of the Arctic Station "Dirigibile Italia" during the field campaigns at Ny-Ålesund.  ... 
doi:10.1029/2020gl091334 fatcat:53oqqfbeija55aiu7e2zlwzv34

Aerosol indirect effects on the nighttime Arctic Ocean surface from thin, predominantly liquid clouds

Lauren M. Zamora, Ralph A. Kahn, Sabine Eckhardt, Allison McComiskey, Patricia Sawamura, Richard Moore, Andreas Stohl
2017 Atmospheric Chemistry and Physics  
microphysics in these types of clouds over the rapidly changing Arctic Ocean.  ...  The cloud subset of focus covers just ∼ 5<span class="thinspace"></span>% of cloudy Arctic Ocean regions, warming the Arctic Ocean surface by ∼<span class="thinspace"></span>1–1.4<span class="thinspace  ...  We recognize and thank the efforts and funding from the large number of people and agencies involved in making the following datasets available, including the NASA Langley Research Center Atmospheric Science  ... 
doi:10.5194/acp-17-7311-2017 pmid:32849860 pmcid:PMC7447155 fatcat:etbkcydj25aj3g44jb6fy4tuqy

Chlorine nitrate in the atmosphere

Thomas von Clarmann, Sören Johansson
2018 Atmospheric Chemistry and Physics  
</strong> This review article compiles the characteristics of the gas chlorine nitrate and discusses its role in atmospheric chemistry.  ...  The latter sink is particularly important in the context of polar spring stratospheric chlorine activation.  ...  The role of heterogeneous reactions on surfaces of cloud particles in the explanation of the Antarctic ozone hole was first discussed by Solomon et al. (1986) , suggesting the relevance of Reaction (R10  ... 
doi:10.5194/acp-18-15363-2018 fatcat:5kidvw6gxfhb3gf43lztcpfi54

Spatial and seasonal distribution of Arctic aerosols observed by the CALIOP satellite instrument (2006–2012)

M. Di Pierro, L. Jaeglé, E. W. Eloranta, S. Sharma
2013 Atmospheric Chemistry and Physics  
of tropospheric Arctic aerosols during the period 2006–2012.  ...  (1–4 Mm<sup>−1</sup>), thus providing the first pan-Arctic view of Arctic haze seasonality.  ...  We like to thank Environment Canada and NOAA for providing the in-situ aerosol data at Alert and Barrow.  ... 
doi:10.5194/acp-13-7075-2013 fatcat:tnyfztq43nf4ncrqovhxj2sgra

Infrared emission measurements in the Arctic using a new extended-range AERI

Z. Mariani, K. Strong, M. Wolff, P. Rowe, V. Walden, P. F. Fogal, T. Duck, G. Lesins, D. S. Turner, C. Cox, E. Eloranta, J. R. Drummond (+4 others)
2011 Atmospheric Measurement Techniques Discussions  
The presence of clouds creates a large surface radiative forcing in the Arctic, particularly in the 750-1200 cm −1 region where the downwelling radiance 25 is several times greater than clear-sky radiances  ...  A previous extended-range version of the AERI system was deployed at the Surface Heat Budget of the Arctic 6415 AMTD Abstract AMTD 4, 6411-6448, 2011 Abstract AMTD 4, 6411-6448, 2011 Infrared emission  ...  This increase is larger for the Arctic than in other more humid regions, indicating that cloud cover plays a crucial role in the Arctic's radiative budget.  ... 
doi:10.5194/amtd-4-6411-2011 fatcat:xlctcwvt5zddbmdk3gyydsusue

Overview paper: New insights into aerosol and climate in the Arctic

Jonathan P. D. Abbatt, W. Richard Leaitch, Amir A. Aliabadi, Allan K. Bertram, Jean-Pierre Blanchet, Aude Boivin-Rioux, Heiko Bozem, Julia Burkart, Rachel Y. W. Chang, Joannie Charette, Jai P. Chaubey, Robert J. Christensen (+58 others)
2019 Atmospheric Chemistry and Physics  
In addition, INPs are abundant in the sea surface microlayer in the Arctic, and possibly play a role in ice nucleation in the atmosphere when mineral dust concentrations are low. (5) Amongst multiple aerosol  ...  Via accumulation of secondary organic aerosol (SOA), a significant fraction of the new particles grow to sizes that are active in cloud droplet formation.  ...  As well, we know very little about the polar night and the associated formation of ice clouds.  ... 
doi:10.5194/acp-19-2527-2019 fatcat:i3qnfsdjlnfmzmxnvtngeqdiqy
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