International Journal of Biometeorology最新文献

Barley (Hordeum vulgare) is a globally significant cereal crop, widely used in both food production and brewing. However, it is particularly vulnerable to climate change, especially extreme temperature fluctuations, which can severely reduce yields. To address this challenge, a detailed climate zoning study was conducted to assess the suitability of barley production areas across South America, considering both current conditions and future climate scenarios from the Intergovernmental Panel on Climate Change (IPCC). The study utilized historical climate data along with projections from the CMIP6 IPSL-CM6A-LR model for the period 2021–2100. Several indices, such as evapotranspiration, were calculated, and factors like soil composition and topography were integrated into the classification of regions based on their agricultural potential. Critical variables in this assessment included temperature, precipitation, and water or thermal excess. The results showed that 6.59% of South America's territory is currently suitable for barley cultivation without additional irrigation, with these regions concentrated primarily in temperate southern areas. In contrast, 18.62% of the region is already unsuitable due to excessive heat. Projections under future climate scenarios indicate a shrinking of suitable areas, alongside an expansion of unsuitable regions. In the worst-case scenario, only 1.48% of the territory would remain viable for barley farming. These findings emphasize the crop's vulnerability to climate change, underscoring the urgency of developing agricultural adaptation strategies. The predicted contraction in suitable barley cultivation areas demonstrates the profound impact of climate change on agriculture and highlights the need for proactive measures to ensure sustainable barley production in South America.

Against the background of climate warming and humidification, the so-called ‘divergence problem’ reduces the stability of tree rings in response to climate, and affects the reliability of tree-ring reconstruction. Investigation of the divergence problem is crucial to improve our understanding of the response patterns of trees to climate warming, and provide a scientific basis for accurate climate reconstruction. Based on tree-ring width data for Siberian larch (Larix sibirica Ledeb.) growing at low elevations in the eastern Altay Mountains, we analyzed the relationship between radial growth of trees and climatic factors in the context of abrupt climate change in this region. We calculated the proportional contribution of five climatic factors to the radial growth of trees, and discussed the response mechanism of radial growth of L. sibirica in combination with large-scale atmospheric circulation patterns. The radial growth of L. sibirica was mainly constrained by water availability. Before climate warming (1961–1990), the radial growth of L. sibirica was mainly limited by temperature in the previous June. After abrupt climate warming (1991–2020), there was a significant positive correlation between growth and soil moisture in the previous winter, suggesting that high temperatures in the following spring would limit tree radial growth if water availability was low. The attribution analysis results revealed that, before 1990, the proportional of relative contribution of temperature to radial growth of trees exceeded 60%. Since 1990, the proportional of relative contribution of water (precipitation and volumetric soil water) to growth of L. sibirica increased. This might reflect the combined effects of local climatic conditions and changes in large-scale atmospheric circulation.

Heat-health warning systems and services are important preventive actions for extreme heat, however, global evidence differs on which temperature indicator is more informative for heat-health outcomes. We comprehensively assessed temperature predictors on their summer associations with adverse health impacts in a high-density subtropical city. Maximum, mean, and minimum temperatures were examined on their associations with non-cancer mortality and hospital admissions in Hong Kong during summer seasons 2010–2019 using Generalized Additive Models and Distributed Lag Non-linear Models. In summary, mean and minimum temperatures were identified as strong indicators for mortality, with a relative risk(RR) and 95% confidence interval(CI) of 1.037 (1.006–1.069) and 1.055 (1.019–1.092), respectively, at 95th percentile vs. optimal temperature. Additionally, minimum temperatures captured the effects of hospital admissions, RR1.009 (95%CI: 1.000- 1.018). In stratified analyses, significant associations were found for older adults, female sex, and respiratory-related outcomes. For comparison, there was no association between maximum temperature and health outcomes. With climate change and projected increase of night-time warming, the findings from this comprehensive assessment method are useful to strengthen heat prevention strategies and enhance heat-health warning systems. Other locations could refer to this comprehensive method to evaluate their heat risk, especially in highly urbanized environments and subtropical cities.

Terrestrial ecosystems are one of the major sinks of atmospheric CO₂ and play a key role in climate change mitigation. Forest ecosystems offset nearly 25% of the global annual CO₂ emissions, and a large part of this is stored in the aboveground woody biomass. Several studies have focused on understanding the carbon sequestration processes in forest ecosystems and their response to climate change using the eddy covariance (EC) technique and remotely sensed vegetation indices. However, very few of them address the linkage of tree-ring growth with the ecosystem-atmosphere carbon exchange, and nearly none have tested this linkage over a long-term (> 100 years) — limited by the short-term (< 50 years) availability of measured ecosystem carbon flux. Nevertheless, tree-ring indices can potentially act as proxies for ecosystem productivity. We utilise the Coupled Climate Carbon Cycle Model Intercomparison Project (C4MIP) model outputs for its 140-year-long simulated records of mean monthly gross primary productivity (GPP) and compare them with the tree-ring growth indices over the northwestern Himalayan region in India. In this study, we examine three coniferous tree species: Pinus roxburghii and Picea smithiana wall. Boiss and Cedrus deodara and find that the strength of the correlation between GPP and tree ring growth indices (RWI) varies among the species.

Heat stress in hyper-prolific lactating sows is recognised as a factor reducing feed intake, milk production, and welfare, with significant losses in farm productivity. Individual capacities for body thermoregulation during environmental hyperthermia determine the adaptation of the animal during long and recurrent events. This study aimed to evaluate the ability of attenuated total reflectance (ATR) mid infrared (MIR) spectroscopy as a high-throughput method to identify markers of stress in plasma and milk collected from lactating sows under heat stress conditions fed with two levels of protein in the diet defined as low (16%) and standard (20%). The MIR spectra were analysed using linear discriminant analysis (LDA) and principal component analysis and validated using cross-validation. The results obtained indicated that MIR spectroscopy, in combination with chemometrics, was able to identify changes in the spectra associated with heat stress in wavenumbers corresponding with amide groups (proteins) (highest loadings observed in the regions between1065 and 1635 cm⁻¹), lipids and unsaturated fatty acids (regions between 1746 and 3063 cm⁻¹), lipo-polysaccharides (in 1247 cm⁻¹) and carbohydrates (around the region1050 cm⁻¹). These results also indicated that the information provided by these wavenumbers can be used as metabolic markers of the adaptation of the sows to hyperthermia. It was concluded that MIR spectroscopy is a rapid and inexpensive tool capable of detecting and evaluating the main biochemical changes of hyperthermia on lactating sows, facilitating the development of palliative management strategies such as dietary manipulations.

The purpose of this study was to design a local ventilation system (LVS) to help reduce the moisture content of a Scalder hall, evaluate its comfort and thermal stress before and after implementation of LVS and introduce an appropriate index to evaluate warm and humid workplaces. The design of the LVS was performed according to the ACGIH standard (VS-30-01). Heat stress and thermal comfort assessment were performed before and after LVS using humidity index (Humidex), discomfort index (DI), heat index (HI), wet-bulb globe temperature (WBGT) and predicted mean vote index (PMV) indices and the results were compared with predicted mean vote index-predicted percentage of dissatisfied (PMV-PPD) subjective indices. The results of heat stress parameters showed that LVS was able to reduce relative humidity (RH) and wet temperature (t_nw) by 47% and 7 ° C, respectively. This has caused subjects to feel the heat from hot and very RH hot to warm and the hot and percentage of dissatisfaction has dropped by more than 70%. Design and implementation of a LVS reduced the ambient t_nw by decreasing RH. Results also showed in warm and humid workplaces, DI index are highly correlated with subjective evaluation of thermal comfort and this index can be used to evaluate the thermal conditions of the workplaces.

Climate change and growing population and their strain on animal production are the impending challenges that the developing countries, like India, need to tackle in the coming days. This study aimed to detect and analyze the uncharacterized variation in the gene expression patterns with the change of condition, from thermoneutral to chronic hot-humid, in the Sahiwal cattle, one of the best breeds of milk-producing cattle in India, known for being heat-tolerant. Using RNA-Seq analysis on peripheral blood mononuclear cells (PBMCs), 4021 differentially expressed mRNAs (2772 upregulated, 1249 downregulated) and 1303 differentially expressed long non-coding RNAs (769 upregulated, 534 downregulated) were identified, with the thresholds of false discovery rate < 0.05 and|log₂(fold change)| > 2. Significantly (p-adjusted < 0.05) overrepresented Gene Ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome pathways were analyzed, revealing upregulation of processes like pyruvate metabolic process, gluconeogenesis, ion transmembrane transport, neuropeptide signaling pathway, and animal organ development, with genes like SHH, GRK1, CHRM3, CAMK2A, and HSPB7 were upregulated, while translation and immune responses, with genes like RPS3, EEF1A1, TNF, BoLA-DRB3, and UBB were downregulated. Analysis of cis-mRNAs of DE-lncRNAs showed presence of both up- and down-regulated cis-mRNAs for both up- and down-regulated lncRNAs indicating existence of positive and negative regulation of mRNA expression by lncRNAs. Managemental nudges that decrease metabolic heat generation, like betaine and chromium supplementation, and increase heat dissipation, like microenvironment cooling, should be utilized. This study highlights the role of pyruvate metabolism and gluconeogenesis in coping up with heat stress and offers an improved understanding of the heat stress response of Sahiwal cattle along with the genes and pathways responsible for it.