Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.1
2.9
Journals
Atmosphere
Special Issues
On the Variability of Atmospheric Transparency: Key Players, Geographic Specificities...
share announcement

On the Variability of Atmospheric Transparency: Key Players, Geographic Specificities and Implications for Daytime Radiative Cooling

A special issue of Atmosphere (ISSN 2073-4433). This special issue belongs to the section "Meteorology".

Deadline for manuscript submissions: closed (2 July 2021) | Viewed by 14070

Special Issue Editors

Dr. Giulia Ulpiani

E-Mail Website
Guest Editor
European Commission, Joint Research Centre (JRC), Ispra, VA, Italy
Interests: radiative cooling; urban heat; heat island mitigation; climate change; outdoor comfort; building energy efficiency
Special Issues, Collections and Topics in MDPI journals
Dr. Chi Yan Tso

E-Mail Website
Guest Editor
School of Energy and Environment, City University of Hong Kong, Hong Kong, China
Interests: thermofluid; energy and built environment; heat transfer; energy efficient building technology
Special Issues, Collections and Topics in MDPI journals
Dr. Yu-Bin Chen

E-Mail Website
Guest Editor
Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu City, Taiwan
Interests: diffraction and scattering; energy harvesting and conversion; infrared radiative cooling; thermal radiation

Special Issue Information

Dear Colleagues,

In about 30 years, the demand for cooling would be three to four-fold, accompanied by an unprecedented air conditioning penetration. To limit the environmental impact, passive and sustainable cooling systems are urgently needed. Daytime radiative cooling is the gold promise of passive cooling and refrigeration in the built environment. It exploits the atmospheric transparency in the so-called atmospheric window (8-13 μm) as a channel to reject heat directly into the outer space, thus reaching sub ambient temperatures even under peak irradiance when high mid-infrared emittance is combined with high solar reflectance. The potential against local climate change is extraordinary under ideal, desert-like conditions. However, any loss of atmospheric transparency, ascribable to humidity, clouds and pollutants, causes the downwelling longwave radiation to increase and the net radiative cooling to diminish, if not to disappear.

Despite being a well-acknowledged issue, a cohesive literature that tackles and quantifies the key variables and geographic variability behind the loss of atmospheric transparency is still missing, just like a well-established methodology to compute the corresponding radiative power loss.

In this framework, this Special Issue aims at publishing high-quality papers targeting the following goals:

  • Collecting criteria and methods to quantify the atmospheric transparency loss as a function of the local atmospheric conditions, climate, geography and air quality;
  • Establishing innovative monitoring systems to measure the atmospheric transparency and capture the key variables involved in the interaction between radiative cooler and atmosphere;
  • Correlating the atmospheric transparency loss with observables at surface level and/or with the radiative cooling power impairment;
  • Interpreting historical data to predict the potential loss of atmospheric transparency at local and global scale in future scenarios;
  • Investigating methods to minimize the radiative cooling sensitivity to atmospheric transparency”.

Dr. Giulia Ulpiani
Dr. Chi Yan Tso
Dr. Yu-Bin Chen
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Atmosphere is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • atmospheric transparency
  • downwelling longwave radiation
  • daytime radiative cooling
  • atmospheric transmission spectrum
  • atmospheric monitoring
  • spectral correlation
  • humidity
  • pollution
  • cloud cover
  • precipitable water vapor

Published Papers (4 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

20 pages, 4224 KiB  
Article
Global Radiative Sky Cooling Potential Adjusted for Population Density and Cooling Demand
by Ablimit Aili, Xiaobo Yin and Ronggui Yang
Atmosphere 2021, 12(11), 1379; https://doi.org/10.3390/atmos12111379 - 21 Oct 2021
Cited by 15 | Viewed by 4026
Abstract
Thanks to recent advances in nanophotonics and scalable manufacturing of metamaterials, radiative sky cooling has emerged as a “self-reliant” cooling technology with various potential applications. However, not every region across the globe is well suited for the adoption of radiative cooling technologies, depending [...] Read more.
Thanks to recent advances in nanophotonics and scalable manufacturing of metamaterials, radiative sky cooling has emerged as a “self-reliant” cooling technology with various potential applications. However, not every region across the globe is well suited for the adoption of radiative cooling technologies, depending on the local climate, population density, cooling demand, air conditioning saturation, economic prosperity, etc. Because the atmospheric downward longwave radiation, especially the portion from the atmospheric window (8–13 µm), is substantially affected by weather conditions, the performance of a well-designed radiative cooler can be vastly different across regions and seasons. Here, we first map the global radiative sky cooling potential in the form of net cooling power density. We then further evaluate it based on the global population density and cooling demand. In terms of the adjusted potential, we show that geographically and demographically “transitional” regions, located between wet and dry climates as well as sparsely and densely populated regions, are better suited for the adoption of radiative cooling technologies because of their temperate climate and moderate population density. Even in densely populated and humid regions, the cumulative impact and other accompanying benefits must not be ignored. Full article
(This article belongs to the Special Issue On the Variability of Atmospheric Transparency: Key Players, Geographic Specificities and Implications for Daytime Radiative Cooling)
►▼ Show Figures

Figure 1

14 pages, 14839 KiB  
Article
Simple Double-Layer Coating for Efficient Daytime and Nighttime Radiative Cooling
by Mourad Benlattar, Issam Ibourk and Rahma Adhiri
Atmosphere 2021, 12(9), 1198; https://doi.org/10.3390/atmos12091198 - 15 Sep 2021
Cited by 3 | Viewed by 2838
Abstract
The passive radiative cooling approach refers to the physical process that pumps heat into outer space via the atmospheric window (8–13 μm) without energy input. The ability to continuously adjust the emissivity of thermal emitters in the sky window while maintaining high reflectivity [...] Read more.
The passive radiative cooling approach refers to the physical process that pumps heat into outer space via the atmospheric window (8–13 μm) without energy input. The ability to continuously adjust the emissivity of thermal emitters in the sky window while maintaining high reflectivity in the solar spectrum remains a challenge. In order to achieve this task, a novel design referred to as double-layer nanoparticle-based coating is proposed. Our proposed emitter is appropriate for both high solar reflection and strong mid-infrared emissivity. The bottom and top layers are Al2O3 embedded with Ni nanoparticles and a super-hydrophilic TiO2-SiO2 layer. The bottom layer is designed to achieve high emissivity in “the atmospheric transparency window”. The top layer is designed to block solar illumination and to favor an enhanced cleanability of the coated design. Our double-layer coating as an optical solar reflector has excellent solar irradiation (0.96) and is strongly emissive (0.97) across the “full sky window” at room temperature. Furthermore, a detailed numerical energy study has been performed, evaluating the temperature reduction and the radiative cooling performance under different conditions. The proposed simple coating can be used as an efficient radiative cooler on a large scale for energy conservation and thermoelectric devices. Full article
(This article belongs to the Special Issue On the Variability of Atmospheric Transparency: Key Players, Geographic Specificities and Implications for Daytime Radiative Cooling)
►▼ Show Figures

Figure 1

10 pages, 2433 KiB  
Article
Accurately Quantifying Clear-Sky Radiative Cooling Potentials: A Temperature Correction to the Transmittance-Based Approximation
by Jyotirmoy Mandal, Xin Huang and Aaswath P. Raman
Atmosphere 2021, 12(9), 1195; https://doi.org/10.3390/atmos12091195 - 15 Sep 2021
Cited by 3 | Viewed by 3273
Abstract
Theoretical calculations of the cooling potential of radiative cooling materials are crucial for determining their cooling capability under different meteorological conditions and evaluating their performance. To facilitate these calculations, accurate models of long-wave infrared downwelling atmospheric irradiance are needed. However, the transmittance-based cosine [...] Read more.
Theoretical calculations of the cooling potential of radiative cooling materials are crucial for determining their cooling capability under different meteorological conditions and evaluating their performance. To facilitate these calculations, accurate models of long-wave infrared downwelling atmospheric irradiance are needed. However, the transmittance-based cosine approximation, which is widely used to determine radiative cooling potentials under clear sky conditions, does not account for the cooling potential arising from heat loss to the colder reaches of the atmosphere itself. Here, we show that use of the approximation can lead to >10% underestimation of the cooling potential relative to MODTRAN 6 outputs. We propose a temperature correction to the transmittance-based approximation, which accounts for heat loss to the cold upper atmosphere, and significantly reduces this underestimation, while retaining the advantages of the original model. In light of the widespread and continued use of the transmittance-based model, our results highlight an important source of potential errors in the calculation of clear sky radiative cooling potentials and a means to correct for them. Full article
(This article belongs to the Special Issue On the Variability of Atmospheric Transparency: Key Players, Geographic Specificities and Implications for Daytime Radiative Cooling)
►▼ Show Figures

Figure 1

14 pages, 2493 KiB  
Article
Mapping Nighttime and All-Day Radiative Cooling Potential in Europe and the Influence of Solar Reflectivity
by Roger Vilà, Marc Medrano and Albert Castell
Atmosphere 2021, 12(9), 1119; https://doi.org/10.3390/atmos12091119 - 31 Aug 2021
Cited by 11 | Viewed by 2412
Abstract
Radiative cooling is a natural process to cool down surfaces through the rejection of thermal radiation using the outer space as a cold sink, taking advantage of the transparency of the atmospheric windows (8–14 μm), which partially matches the infrared radiation band. With [...] Read more.
Radiative cooling is a natural process to cool down surfaces through the rejection of thermal radiation using the outer space as a cold sink, taking advantage of the transparency of the atmospheric windows (8–14 μm), which partially matches the infrared radiation band. With the development of new materials that have a high reflectivity of solar radiation, daytime radiative cooling can be achieved. This phenomenon depends on the optical properties of the surface and the local weather conditions. In this research, climatological data from 1791 weather stations were used to present detailed nighttime and all-day radiative cooling maps for the potential implementation of radiative cooling-based technologies. The paper offers a parametric study of the variation of the potential as a result of decreasing the solar reflectivity. The results show that southern Europe is the region with the highest potential while northern Europe holds more hours of available radiative cooling. After varying the solar reflectivity from 1 to 0.5 the average power reduces from 60.18 to 45.32 W/m2, and energy from 527.10 to 264.87 kWh/m2·year. For solar reflectivity lower than 0.5, all-day radiative coolers behave as nighttime radiative coolers, but power and energy values improve significantly for high values of solar reflectivity. Small variations of solar reflectivity have greater impacts on the potential at higher reflectivity values than at lower ones. Full article
(This article belongs to the Special Issue On the Variability of Atmospheric Transparency: Key Players, Geographic Specificities and Implications for Daytime Radiative Cooling)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-4
Back to TopTop