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1. Asymmetry of thermal sensitivity and the thermal risk of climate change

   https://doi.org/10.1111/geb.13570  

   Buckley, Lauren B.; Huey, Raymond B.; Kingsolver, Joel G. (July 2022, Global Ecology and Biogeography)

   Abstract AimUnderstanding and predicting the biological consequences of climate change requires considering the thermal sensitivity of organisms relative to environmental temperatures. One common approach involves ‘thermal safety margins’ (TSMs), which are generally estimated as the temperature differential between the highest temperature an organism can tolerate (critical thermal maximum, CT_max) and the mean or maximum environmental temperature it experiences. Yet, organisms face thermal stress and performance loss at body temperatures below their CT_max,and the steepness of that loss increases with the asymmetry of the thermal performance curve (TPC). LocationGlobal. Time period2015–2019. Major taxa studiedAnts, fish, insects, lizards and phytoplankton. MethodsWe examine variability in TPC asymmetry and the implications for thermal stress for 384 populations from 289 species across taxa and for metrics including ant and lizard locomotion, fish growth, and insect and phytoplankton fitness. ResultsWe find that the thermal optimum (T_opt, beyond which performance declines) is more labile than CT_max, inducing interspecific variation in asymmetry. Importantly, the degree of TPC asymmetry increases with T_opt. Thus, even though populations with higher T_opts in a hot environment might experience above‐optimal body temperatures less often than do populations with lower T_opts, they nonetheless experience steeper declines in performance at high body temperatures. Estimates of the annual cumulative decline in performance for temperatures above T_optsuggest that TPC asymmetry alters the onset, rate and severity of performance decrement at high body temperatures. Main conclusionsSpecies with the same TSMs can experience different thermal risk due to differences in TPC asymmetry. Metrics that incorporate additional aspects of TPC shape better capture the thermal risk of climate change than do TSMs. 

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2. The thermal ecology of flowers

   https://doi.org/10.1093/aob/mcz073  

   van der Kooi, Casper J; Kevan, Peter G; Koski, Matthew H (June 2019, Annals of Botany)

   Abstract Background Obtaining an optimal flower temperature can be crucial for plant reproduction because temperature mediates flower growth and development, pollen and ovule viability, and influences pollinator visitation. The thermal ecology of flowers is an exciting, yet understudied field of plant biology. Scope This review focuses on several attributes that modify exogenous heat absorption and retention in flowers. We discuss how flower shape, orientation, heliotropic movements, pubescence, coloration, opening–closing movements and endogenous heating contribute to the thermal balance of flowers. Whenever the data are available, we provide quantitative estimates of how these floral attributes contribute to heating of the flower, and ultimately plant fitness. Outlook Future research should establish form–function relationships between floral phenotypes and temperature, determine the fitness effects of the floral microclimate, and identify broad ecological correlates with heat capture mechanisms. 

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3. Minimum thermal conductivity in the context of diffuson -mediated thermal transport

   https://doi.org/10.1039/c7ee03256k  

   Agne, Matthias T.; Hanus, Riley; Snyder, G. Jeffrey (January 2018, Energy & Environmental Science)

   A model for the thermal conductivity of bulk solids is proposed in the limit of diffusive transport mediated by diffusons as opposed to phonons. This diffusive thermal conductivity, κ diff , is determined by the average energy of the vibrational density of states, ℏ ω avg , and the number density of atoms, n . Furthermore, κ diff is suggested as an appropriate estimate of the minimum thermal conductivity for complex materials, such that (at high temperatures): . A heuristic finding of this study is that the experimental ω avg is highly correlated with the Debye temperature, allowing κ diff to be estimated from the longitudinal and transverse speeds of sound: . Using this equation to estimate κ min gives values 37% lower than the widely-used Cahill result and 18% lower than the Clarke model for κ min , on average. This model of diffuson-mediated thermal conductivity may thus help explain experimental results of ultralow thermal conductivity. 

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4. Understanding the Influence of Short-Term Thermal History on Personalized Thermal Comfort Votes

   Jung, W.; Jazizadeh, F. (January 2021, eSIM 2021)
5. Thermal structure of the blue whirl

   https://doi.org/10.1016/j.proci.2018.05.115  

   Hariharan, Sriram Bharath; Sluder, Evan T.; Gollner, Michael J.; Oran, Elaine S. (January 2019, Proceedings of the Combustion Institute)