Darwin and the biological rhythms
While the formalization of chronobiology as a scientific discipline occurred in the mid-20th century, the exploration of rhythmic phenomena has a longer history, notably exemplified by De Mairan’s observations of Mimosa pudica in darkness in 1729. In this historical narrative, Charles Darwin is known for his investigations into the “sleep movements” of plants. Nevertheless, the complete scope of Darwin’s exploration of biological rhythms remains incompletely understood. Through a detailed examination of Darwin’s writings, meticulous observations, experiments, and conceptualizations, we unveil a depth of engagement that surpasses his widely acknowledged work on plants, revealing a more extensive interest in and insight into biological rhythms than traditionally recognized.
Journal Reference:
Tiago G de Andrade et al, ‘Darwin and the biological rhythms’, PNAS Nexus (2024). DOI: 10.1093/pnasnexus/pgae318
How can event attribution science underpin financial decisions on Loss and Damage?
With climate extremes hitting nations across the globe, disproportionately burdening vulnerable developing countries, the prompt operation of the Loss and Damage fund is of paramount importance. As decisions on resource disbursement at the international level, and investment strategies at the national level, loom, the climate science community’s role in providing fair and effective evidence is crucial. Attribution science can provide useful information for decision makers, but both ethical implications and deep uncertainty cannot be ignored. Considering these aspects, we articulate a vision that integrates established attribution methods and multiple lines of evidence within a coherent logical framework.
Journal Reference:
Dim Coumou, Paola A Arias, Ana Bastos, Charlotte Kendra Gotangco Gonzales, Gabriele C Hegerl, Pandora Hope, Christopher Jack, Friederike Otto, Fahad Saeed, Olivia Serdeczny, Theodore G Shepherd, Robert Vautard, ‘How can event attribution science underpin financial decisions on Loss and Damage?’, PNAS Nexus (vol. 3, Iss. 8, pgae277, 2024). DOI: 10.1093/pnasnexus/pgae277
Solar irradiance variability around Asia Pacific: Spatial and temporal perspective for active use of solar energy
This study discusses solar irradiance variability in the spatial and temporal domains for the active use of solar energy. The spatial domain was calculated using the difference between one location and another in a focused small tile area. The principal component analysis (PCA) was used for this analysis in the spatial and temporal domain. The Umbrella Effect Index (UI) was calculated to determine the probability of an umbrella effect event within a specific time range. This study discusses solar irradiance variability using solar irradiance data analyzed every 10 min from high-temporal observations of geostationary satellites in the Asia-Pacific region. This study shows that solar heterogeneity around the Asia-Pacific ranges from 0–135 W/m2 with a high tendency in the area around the equator and highlands. In addition, this study also shows that the Asia Pacific region has umbrella effect events of approximately 50–2224 h/year with an index ranging approximately 0–0.34. This study presents the annual analysis and seasonal trends of solar irradiance variability over the entire study area. Determining seasonal trends is important because electricity demand fluctuates significantly as seasons progress. An integrated analysis of heterogeneity and UI revealed trends in spatiotemporal variations in solar irradiance. This approach provides useful information for optimizing and managing the locations for installing solar power plants. Moreover, an evaluation of existing solar power plants is presented. Evaluations based on spatiotemporal data reveal impossible characteristics using traditional approaches that use long-term simple averages or typical solar irradiance data. This research shows the distributed photovoltaic (PV) system in wide area can increase the stability of solar energy supply to the grid.
Journal Reference:
Kalingga Titon Nur Ihsan, Hideaki Takenaka, Atsushi Higuchi, Anjar Dimara Sakti, Ketut Wikantika, ‘Solar irradiance variability around Asia Pacific: Spatial and temporal perspective for active use of solar energy’, Solar Energy (vol. 276, 2024). DOI: 10.1016/j.solener.2024.112678
Extreme summer temperature anomalies over Greenland largely result from clear-sky radiation and circulation anomalies
The polar regions have been undergoing amplified warming in recent years. In particular, Greenland has experienced anomalously warm summers with intense melt rates. We employ a surface radiation budget framework to examine the causes for positive and negative summer temperature anomaly events over Greenland from 1979 to 2021. We found a dominant contribution of the clear-sky downwelling longwave radiation and the surface albedo feedback to temperature anomalies. Atmospheric temperature perturbations dominate the effect of anomalous emissivity on clear-sky downwelling longwave radiation. In warm years, enhanced turbulent heat exchange due to increased surface temperature and diabatic warming in the troposphere induces adiabatic heating of the atmosphere, enhanced moisture advection, and a high-pressure anomaly with a blocking-like anti-cyclonic circulation anomaly following peak temperature days. Different modes of natural climate variability, in particular, related to blocking over Greenland, can further amplify or dampen the ongoing warming trend, causing extreme temperature events.
Journal Reference:
Blau, M.T., Ha, KJ. & Chung, ES. ‘Extreme summer temperature anomalies over Greenland largely result from clear-sky radiation and circulation anomalies’, Communications Earth & Environment 5, 405 (2024). DOI: 10.1038/s43247-024-01549-7
Trends of heat-related deaths in the US, 1999-2023
This study found that heat-related mortality rates in the U.S. increased between 1999 and 2023, especially during the last 7 years. Although a study using data through 2018 found a downward trend in heat-related mortality in the U.S., this study is the first to our knowledge to demonstrate a reversal of this trend from 2016 to 2023. These results align with site-specific data analyzed in a global study that suggest increases in heat-related mortality. As temperatures continue to rise because of climate change, the recent increasing trend is likely to continue. Local authorities in high-risk areas should consider investing in the expansion of access to hydration centers and public cooling centers or other buildings with air conditioning.
Journal Reference:
Howard JT, Androne N, Alcover KC, Santos-Lozada AR. ‘Trends of Heat-Related Deaths in the US, 1999-2023’, JAMA (Published online August 26, 2024). DOI: 10.1001/jama.2024.16386
Featured image credit: kjpargeter | Freepik
