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1. Investigating the Urban Air Quality Effects of Cool Walls and Cool Roofs in Southern California

   https://doi.org/10.1021/acs.est.9b00626  

   Zhang, Jiachen; Li, Yun; Tao, Wei; Liu, Junfeng; Levinson, Ronnen; Mohegh, Arash; Ban-Weiss, George (June 2019, Environmental Science & Technology)
2. On the survival of cool clouds in the circumgalactic medium

   https://doi.org/10.1093/mnras/stz3567  

   Li, Zhihui; Hopkins, Philip F; Squire, Jonathan; Hummels, Cameron (February 2020, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT We explore the survival of cool clouds in multiphase circumgalactic media. We revisit the ‘cloud-crushing problem’ in a large survey of simulations including radiative cooling, self-shielding, self-gravity, magnetic fields, and anisotropic Braginskii conduction and viscosity (with saturation). We explore a wide range of parameters including cloud size, velocity, ambient temperature and density, and a variety of magnetic field configurations and cloud turbulence. We find that realistic magnetic fields and turbulence have weaker effects on cloud survival; the most important physics is radiative cooling and conduction. Self-gravity and self-shielding are important for clouds that are initially Jeans-unstable, but largely irrelevant otherwise. Non-self-gravitating, realistically magnetized clouds separate into four regimes: (1) at low column densities, clouds evaporate rapidly via conduction; (2) a ‘failed pressure confinement’ regime, where the ambient hot gas cools too rapidly to provide pressure confinement for the cloud; (3) an ‘infinitely long-lived’ regime, in which the cloud lifetime becomes longer than the cooling time of gas swept up in the leading bow shock, so the cloud begins to accrete and grow; and (4) a ‘classical cloud destruction’ regime, where clouds are eventually destroyed by instabilities. In the final regime, the cloud lifetime can exceed the naive cloud-crushing time owing to conduction-induced compression. However, small and/or slow-moving clouds can also evaporate more rapidly than the cloud-crushing time. We develop simple analytic models that explain the simulated cloud destruction times in this regime. 

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3. 15NH3 in the atmosphere of a cool brown dwarf

   https://doi.org/10.1038/s41586-023-06813-y  

   Barrado, David; Mollière, Paul; Patapis, Polychronis; Min, Michiel; Tremblin, Pascal; Ardevol_Martinez, Francisco; Whiteford, Niall; Vasist, Malavika; Argyriou, Ioannis; Samland, Matthias; et al (December 2023, Nature)
4. A Literature Review of Cooling Center, Misting Station, Cool Pavement, and Cool Roof Intervention Evaluations

   https://doi.org/10.3390/atmos13071103  

   Black-Ingersoll, Flannery; de Lange, Julie; Heidari, Leila; Negassa, Abgel; Botana, Pilar; Fabian, M. Patricia; Scammell, Madeleine K. (July 2022, Atmosphere)

   Heat islands and warming temperatures are a growing global public health concern. Although cities are implementing cooling interventions, little is known about their efficacy. We conducted a literature review of field studies measuring the impact of urban cooling interventions, focusing on cooling centers, misting stations, cool pavements, and cool or green roofs. A total of 23 articles met the inclusion criteria. Studies of cooling centers measured the potential impact, based on evaluations of population proximity and heat-vulnerable populations. Reductions in temperature were reported for misting stations and cool pavements across a range of metrics. Misting station use was evaluated with temperature changes and user questionnaires. The benefits and disadvantages of each intervention are presented, and metrics for evaluating cooling interventions are compared. Gaps in the literature include a lack of measured impacts on personal thermal comfort, limited documentation on intervention costs, the need to standardize temperature metrics, and evaluation criteria. 

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5. The TIME Table: rotation and ages of cool exoplanet host stars

   https://doi.org/10.1093/mnras/stad343  

   Gaidos, Eric; Claytor, Zachary; Dungee, Ryan; Ali, Aleezah; Feiden, Gregory A. (February 2023, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT Age is a stellar parameter that is both fundamental and difficult to determine. Among middle-aged M dwarfs, the most prolific hosts of close-in and detectable exoplanets, gyrochronology is the most promising method to assign ages, but requires calibration by rotation-temperature sequences (gyrochrones) in clusters of known ages. We curated a catalogue of 249 late K- and M-type (Teff = 3200–4200 K) exoplanet host stars with established rotation periods, and applied empirical, temperature-dependent rotation–age relations based on relevant published gyrochrones, including one derived from observations of the 4-Gyr-old open cluster M67. We estimated ages for 227 of these stars, and upper limits for eight others, excluding 14 which are too rapidly rotating or are otherwise outside the valid parameter range of our gyrochronology. We estimated uncertainties based on observed scatter in rotation periods in young clusters, error in the gyrochrones, and uncertainties in temperature and non-solar metallicity. For those stars with measured metallicities, we provide but do not incorporate a correction for the effects of deviation from solar-metallicity. The age distribution of our sample declines to near zero at 10 Gyr, the age of the Galactic disc, with the handful of outliers explainable by large uncertainties. Continued addition or extension of cluster rotation sequences to more thoroughly calibrate the gyrochronology in time and temperature space, more precise and robust measurement of rotation periods, and more accurate stellar parameter measurements will enable continued improvements in the age estimates of these important exoplanet host stars. 

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