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Based on NCEP/NCAR reanalysis data， the leading modes of the westerly jet over the Asian continent during July-August from 1960 to 2019 and the associated mid-to-high latitude circulations has been investigated in this study.The results show that the first leading mode is characterized by an out-of-phase variation in the south-north direction along the jet axis， resulting in a north-south movement of the jet.The second leading mode exhibits an out-of-phase variation in the east-west direction along the Qinghai-Xizang （Tibetan） Plateau， as a southwest （northwest） - northeast （southeast） tilt of the jet stream axis， which is different from most previous studies emphasizing the intensity variations in the second mode.For the first leading mode， associated with the northward movement of the jet streams， the South Asian High （SAH） moves northward as well as the western Pacific subtropical high （WPSH） northward narrows and vice versa.Furthermore， this first leading mode is associated with the tripolar precipitation pattern over East Asia.Particularly， as the jet stream shifts northward （southward）， the precipitation decreases （increases） in the Jianghuai River and increases （decreases） in South China and North China.As well， the associated temperature variations also show a tripolar pattern over the Eurasian continent， with the boundary of around 20°N and 45°N.It suggests that when the jet stream moves northward， warm （cold） conditions cover East Asia， particularly in the central and eastern regions of China， the Korean Peninsula and Japan， while cold （warm） conditions dominant Lake Baikal， the Indian Peninsula and Indochina Peninsula.As for the second leading mode， the geopotential height in the east （west） side of the SAH increases due to the southwest （northwest）-northeast （southeast） tilt of the jet axis.Additionally， the second mode is related to the precipitation anomalies in the high latitudes of West Asia， Central Asia， and the Indian Peninsula.This mode is particularly important for the double dipole temperature pattern over the Eurasian continent.When the jet stream axis presents a southwest （northwest）-northeast （southeast） tilt， significant positive （negative） temperature anomalies are observed in the middle latitudes of East Asia and specifically in the high latitudes of West Asia.

Assessing the impacts of anthropogenic land use and land cover change (LULCC) on climate extremes is crucial for the public. This necessitates the utilization of state-of-the-art experiments and datasets to enhance our understanding. Here, we used CMIP6-LUMIP experimental results to show the biogeophysical effects of LULCC on extreme temperature and precipitation during the historical period. Three regions with intense LULCC in the Northern Hemisphere experienced cooling effects caused by LULCC. In contrast, only the highest maximum temperature (TXx) showed slight warming effects in three regions with intense LULCC in the Southern Hemisphere near the tropics. The maximum changes in intensity were an ∼ 0.8 °C decrease in the TXx and nearly a 2 °C decrease in the 90th percentile in the lowest minimum temperature (TNn) in North America. South Asia experienced ∼ 4% and 10-day decreases in warm days (TX90p) and warm spell duration (WSDI), respectively, in the 90th percentile. The precipitation response to LULCC displayed a clear difference between the Northern Hemisphere (wetter) and the Southern Hemisphere (drier), especially in terms of mean precipitation and wet days (R1mm). Previous studies support our findings that the impacts of LULCC on temperature extremes are greater in regions with intense LULCC than in remote areas. Seasonal results showed that March-April-May (MAM) and June-July-August (JJA) contributed more to the maximum temperature changes, while the minimum temperature experienced greater responses in MAM and December-January-February (DJF). LULCC tended to induce a shift toward either warmer and drier conditions or wetter and colder conditions in approximately two-thirds of season–region pairs. [ABSTRACT FROM AUTHOR]

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Approximately 11% of the world’s population lives within 10 km of an ocean coastline, a percentage that is likely to increase during the remainder of the 21st century due to urbanization and economic development. In the presence of climate change, coastal communities will be threatened by increasing damages due to sea-level rise (SLR), accompanied by hurricanes, storm surges and coastal inundation, shoreline erosion, and seawater intrusion into the soil. While the past decade has seen numerous proposals for coastal protection using adaptation methods to deal with the deep uncertainties associated with a changing climate, our review of the potential impact of SLR on the resilience of coastal communities reveals that these adaptation methods have not been informed by community resilience or recovery goals. Moreover, since SLR is likely to continue over the next century, periodic changes to these community goals may be necessary for public planning and risk mitigation. Finally, community policy development must be based on a quantitative risk-informed life-cycle basis to develop public support for the substantial public investments required. We propose potential research directions to identify effective adaptation methods based on the gaps identified in our review, culminating in a decision framework that is informed by community resilience goals and metrics and risk analysis over community infrastructure life cycles. [ABSTRACT FROM AUTHOR]

Abstract Background Climate is an important driver of ungulate life-histories, population dynamics, and migratory behaviors. Climate conditions can directly impact ungulates via changes in the costs of thermoregulation and locomotion, or indirectly, via changes in habitat and forage availability, predation, and species interactions. Many studies have documented the effects of climate variability and climate change on North America’s ungulates, recording impacts to population demographics, physiology, foraging behavior, migratory patterns, and more. However, ungulate responses are not uniform and vary by species and geography. Here, we present a systematic map describing the abundance and distribution of evidence on the effects of climate variability and climate change on native ungulates in North America. Methods We searched for all evidence documenting or projecting how climate variability and climate change affect the 15 ungulate species native to the U.S., Canada, Mexico, and Greenland. We searched Web of Science, Scopus, and the websites of 62 wildlife management agencies to identify relevant academic and grey literature. We screened English-language documents for inclusion at both the title and abstract and full-text levels. Data from all articles that passed full-text review were extracted and coded in a database. We identified knowledge clusters and gaps related to the species, locations, climate variables, and outcome variables measured in the literature. Review findings We identified a total of 674 relevant articles published from 1947 until September 2020. Caribou (Rangifer tarandus), elk (Cervus canadensis), and white-tailed deer (Odocoileus virginianus) were the most frequently studied species. Geographically, more research has been conducted in the western U.S. and western Canada, though a notable concentration of research is also located in the Great Lakes region. Nearly 75% more articles examined the effects of precipitation on ungulates compared to temperature, with variables related to snow being the most commonly measured climate variables. Most studies examined the effects of climate on ungulate population demographics, habitat and forage, and physiology and condition, with far fewer examining the effects on disturbances, migratory behavior, and seasonal range and corridor habitat. Conclusions The effects of climate change, and its interactions with stressors such as land-use change, predation, and disease, is of increasing concern to wildlife managers. With its broad scope, this systematic map can help ungulate managers identify relevant climate impacts and prepare for future changes to the populations they manage. Decisions regarding population control measures, supplemental feeding, translocation, and the application of habitat treatments are just some of the management decisions that can be informed by an improved understanding of climate impacts. This systematic map also identified several gaps in the literature that would benefit from additional research, including climate effects on ungulate migratory patterns, on species that are relatively understudied yet known to be sensitive to changes in climate, such as pronghorn (Antilocapra americana) and mountain goats (Oreamnos americanus), and on ungulates in the eastern U.S. and Mexico.

Pollen can serve as an effective ice‐nuclei (IN), altering cloud microphysical and radiative properties, thus precipitation and cloud life cycles. Here, a nationwide pollen emission inventory with a horizontal resolution of 5 km was established based on a parameterization scheme of mass balance of pollen grain fluxes surrounding the plant crowns, and using satellite observational data sets (including leaf area index and fractional vegetation cover) as well as pollen emission rates. The potential emission is then implemented in RegCM‐pollen model which treated pollen as aerosol tracers. Besides, pollen‐IN parameterization schemes were incorporated in RegCM‐pollen to simulate the interactions between pollen and ice clouds. Investigations show that the mean annual pollen emission in China is 2.65 × 107 grains m−2 yr−1, mainly distributed in the south and northeast of China. The IN magnitude is mainly determined by a combination of temperature and pollen concentration. Notably, an increasing number concentration of pollen grains produces opposite effects in Southern China (SC) and Northern China (NC). The weakened upward motion and vertical transport of water vapor in NC made ice clouds hardly form, resulting in cloud forcing (CF) of +0.86 W/m2. In contrast, it generates a CF of −0.84 W/m2 in SC mainly owing to expanded cloud cover. The changes in shortwave radiative forcing is more significant compared to longwave radiative forcing in the two regions. At the surface, the net radiative forcing in NC is +0.74 W/m2, while it is a −0.51 W/m2 in SC. Among them, downward shortwave radiative forcing is approximately twice that of upward longwave radiative forcing in SC and 1.4 times in NC. Surface temperature shows rising over NC, ranging from 0.05 to 0.25 K. In SC, it is primarily decreasing by −0.12 to −0.03 K. The pollen‐IN effect also causes a decline of precipitation in NC (−0.17 mm/day) and a rise in SC (0.09 mm/day). Our results suggest that the pollen effect on ice clouds is complex, yet significant in understanding its impact on radiation and climate of the atmosphere. Plain Language Summary: Bioaerosols such as pollen are emitted into the atmosphere from the terrestrial biosphere. They can affect cloud formation as ice nuclei, thus influencing radiation and climate. Whereas, up to now little is understood about the ice‐nucleating properties of pollen and how they impact cloud and precipitation formation. In this work, the RegCM‐pollen was utilized to quantitatively estimate vegetation pollen emissions in China and their induced radiative forcing and climate responses. We found that higher airborne pollen is chiefly concentrated in Southern China (SC) and Northern China (NC). The ice nucleation effect of pollen generates contrasting effects in the two areas. A positive effect on cloud forcing (CF) in NC is mainly owing to the inhibition of upward motion and reduced vertical transport of water vapor not conducive to the formation of ice clouds. On the opposite, the negative effect on CF in SC is mostly influenced by the enhanced water vapor, thus, expanding the coverage of the ice cloud. Key Points: Model simulations show that airborne pollen is mainly concentrated in Southern China (SC) and Northern China (NC) with seasonal variationsPollen‐induced IN concentrations decrease with altitude, exhibiting large gradient at a given height, particularly above 7 kmOpposite cloud forcing caused by pollen ice nuclei effect was found in SC (−0.84 W/m2) and NC (+0.86 W/m2) mainly due to water vapor difference in these two regions [ABSTRACT FROM AUTHOR]

Phyllosphere microbes residing on plant leaf surfaces for maintaining plant health have gained increasing recognition. However, in desert ecosystems, knowledge about the variety, composition, and coexistence patterns of microbial communities in the phyllosphere remains limited. This study, conducted across three basins (Turpan-TLF, Tarim-CL, and Dzungaria-MSW) and three seasons (spring, summer, and autumn) in Xinjiang, China, aimed to explore the diversity and composition of microbial communities in the phyllosphere, encompassing both bacteria and fungi in Alhagi sparsifolia. We also investigated the co-occurrence patterns, influencing factors, and underlying mechanisms driving these dynamics. Results indicate that phyllosphere bacteria exhibited lower diversity indices (ACE, Shannon, Simpson, Fisher phylogenetic diversity, and Richness) in spring compared to summer and autumn, while the Goods Coverage Index (GCI) was higher in spring. Conversely, diversity indices and GCI of phyllosphere fungi showed an opposite trend. Interestingly, the lowest level of multi-functionality and niche width in phyllosphere bacteria occurred in spring, while the highest level was observed in phyllosphere fungi. Furthermore, the study revealed that no significant differences in multi-functionality were found among the regions (CL, MSW, and TLF). Network analysis highlighted that during spring, phyllosphere bacteria exhibited the lowest number of nodes, edges, and average degree, while phyllosphere fungi had the highest. Surprisingly, the multi-functionality of both phyllosphere bacteria and fungi showed no significant correlation with climatic and environmental factors but displayed a significant association with the morphological characteristics and physicochemical properties of leaves. Structural Equation Model indicated that the morphological characteristics of leaves significantly influenced the multifunctionality of phyllosphere bacteria and fungi. However, the indirect and total effects of climate on multi-functionality were greater than the effects of physicochemical properties and morphological characteristics of leaves. These findings offer new insights into leaf phyllosphere microbial community structure, laying a theoretical foundation for vegetation restoration and rational plant resource utilization in desert ecosystems. [ABSTRACT FROM AUTHOR]

Background: Climate is an important driver of ungulate life-histories, population dynamics, and migratory behaviors. Climate conditions can directly impact ungulates via changes in the costs of thermoregulation and locomotion, or indirectly, via changes in habitat and forage availability, predation, and species interactions. Many studies have documented the effects of climate variability and climate change on North America's ungulates, recording impacts to population demographics, physiology, foraging behavior, migratory patterns, and more. However, ungulate responses are not uniform and vary by species and geography. Here, we present a systematic map describing the abundance and distribution of evidence on the effects of climate variability and climate change on native ungulates in North America. Methods: We searched for all evidence documenting or projecting how climate variability and climate change affect the 15 ungulate species native to the U.S., Canada, Mexico, and Greenland. We searched Web of Science, Scopus, and the websites of 62 wildlife management agencies to identify relevant academic and grey literature. We screened English-language documents for inclusion at both the title and abstract and full-text levels. Data from all articles that passed full-text review were extracted and coded in a database. We identified knowledge clusters and gaps related to the species, locations, climate variables, and outcome variables measured in the literature. Review findings: We identified a total of 674 relevant articles published from 1947 until September 2020. Caribou (Rangifer tarandus), elk (Cervus canadensis), and white-tailed deer (Odocoileus virginianus) were the most frequently studied species. Geographically, more research has been conducted in the western U.S. and western Canada, though a notable concentration of research is also located in the Great Lakes region. Nearly 75% more articles examined the effects of precipitation on ungulates compared to temperature, with variables related to snow being the most commonly measured climate variables. Most studies examined the effects of climate on ungulate population demographics, habitat and forage, and physiology and condition, with far fewer examining the effects on disturbances, migratory behavior, and seasonal range and corridor habitat. Conclusions: The effects of climate change, and its interactions with stressors such as land-use change, predation, and disease, is of increasing concern to wildlife managers. With its broad scope, this systematic map can help ungulate managers identify relevant climate impacts and prepare for future changes to the populations they manage. Decisions regarding population control measures, supplemental feeding, translocation, and the application of habitat treatments are just some of the management decisions that can be informed by an improved understanding of climate impacts. This systematic map also identified several gaps in the literature that would benefit from additional research, including climate effects on ungulate migratory patterns, on species that are relatively understudied yet known to be sensitive to changes in climate, such as pronghorn (Antilocapra americana) and mountain goats (Oreamnos americanus), and on ungulates in the eastern U.S. and Mexico. [ABSTRACT FROM AUTHOR]

Spatial patterns and environmental gradients in plant traits can elucidate the relationships between plant characteristics, environmental factors, and ecosystem functions and can be used to develop the next generation of vegetation models for predicting vegetation distribution and functions. Studies of Plant traits across spatial scales have advanced significantly worldwide, including on the Tibetan Plateau (TP), the highest and largest plateau globally. Previous research on plant traits on the TP has been limited to specific areas, leaving the overall trend across the plateau unclear. In this study, we examined seven leaf traits—leaf thickness (LT), leaf dry matter content (LDMC), leaf area (LA), specific leaf area (SLA), and leaf carbon (LCC), nitrogen (LNC), and phosphorus (LPC) contents—in 1314 individuals at 237 sites within the alpine vegetation region above 3000 m on the TP to determine their distribution patterns across three spatial dimensions and their relationships with environmental factors. Our results indicated that, compared with Chinese plants, TP plants exhibited significantly greater LT, LDMC, and LNC but lower LA, LCC, and LPC. Except for SLA and LCC, most leaf traits showed significant spatial variability. Climate and soil explained 29.23 % of the total variations in traits. Radiation had the most pronounced effect on LDMC, LA, LNC, and LPC, whereas soil pH primarily constrained LT and LCC. Precipitation influenced most traits both directly and indirectly, with substantial overall effects. Temperature and soil nutrient had minimal influence on the regulation of leaf traits across most of the TP. Our findings suggest that alpine plants typically employ a conservative strategy to cope with the harsh conditions on the TP, but this strategy varies at broader spatial scales and longer environmental gradients, particularly in extreme environments such as the highest alpine regions.

Abstract Key message The forest canopy gaps, formed by natural or anthropogenic factors, have been found to reduce soil carbon content and increase nutrient availability. The magnitudes of these effects have been observed to increase with gap age and size, and are largely influenced by changes in temperature, precipitation, and solar radiation. Context Local studies have illustrated the influence of canopy gaps on the spatial heterogeneity of soil carbon and nutrients, playing a pivotal role in driving forest regeneration and succession. Nevertheless, it remains largely unknown whether the response of soil carbon and nutrient content to gap formation is consistent across forest ecosystems at global scale. Aims The aim of this paper is to assess the homogeneity of the observed responses of soil carbon and nutrients following gap formation among a wide array of forest ecosystems and climatic regions. Methods We performed a meta-analysis synthesizing 2127 pairwise observations from 52 published articles to quantify the changes in in soil physical, chemical, and microbial variables resulting from gap creation in natural forests and plantations spanning tropical to boreal regions. Results Canopy gaps resulted in significant decrease of soil organic carbon (C org) and microbial carbon (C mic). The concentrations of ammonium (NH4 +), nitrate (NO3 −), and available phosphorus (available P) increased following gap creation. These changes mainly occurred in the growing season and in the mineral soil layer, becoming more pronounced with increasing gap age and size. The change in C org was negatively regulated by mean annual precipitation, and was associated with the changes in Nt and N mic . The change in NH4 + was positively regulated by mean annual temperature, and was associated with the changes in available P and oxidoreductases (Ox-EEAs). The model explaining the change in soil carbon content exhibited a higher explanatory power than the one accounting for changes in soil nutrient availability. Conclusion The results indicated that forest canopy gaps resulted in a reduction in soil carbon content and an increase in nutrient availability. These findings contribute to a better understanding of the role of small-scale disturbances as drivers of forest ecosystem succession.

Motives for fishing differ among fishers, which may imply different effects of climate change on the net values of fishing. Climate change has impacts on fish population dynamics and on other factors in the fishers' harvest decision, such as alternative sources of food or income. Here we present a bio-economic model that includes impacts of climate change on fish population and on net values of harvest by fishers with recreational or subsistence fishing motives. The conceptual analysis shows that the economic effects of climate change with simultaneous impacts on fish population growth and harvest values are inconclusive with common fishing access for both fisher types and when there are opposite simultaneous climate effects with exclusive access for one of the fisher types. Numerical results from our model of Arctic char (Salvelinus alpinus) in northern Sweden indicate that climate change, measured as temperature increases, reduces fish population growth but increases net values of fishing for both fisher types. The combined net effect of these counteracting forces is that annual net values can almost cease for the subsistence fisher in the future but increase considerably for the recreational fisher. [ABSTRACT FROM AUTHOR]

The estimation of plant‐available soil water (PASW) is essential to quantify transpiration fluxes, the onset of heatwaves, irrigation water management, land‐use decisions, vegetation ecology, and land surface memory in climate models. PASW is the amount of stored water available for plant use. It is broadly defined as the difference between soil water content at field capacity (FC) and wilting point (WP) in the root zone. The limiting states of FC and WP are linked to gravitational drainage and plant physiology and are often deduced from soil water characteristics at prescribed matric potentials (−3.3 and −150 m for FC and WP, respectively). Evidence suggests that static definition of FC at a constant matric potential ignores dynamic effects on FC attainment affected by soil and climate. Here, we revise the definition of PASW by considering (a) soil‐specific dynamic effects and (b) local climate effects of evaporation and rainfall frequency on PASW. The new global PASW maps benefit from state‐of‐the‐art soil maps, water characteristic parameterization, and incorporation of dynamic definition of FC. For completeness we provide static and dynamic PASW estimates. Globally, ice‐free soils store up to 19,941 km3 of water in the top 1 m (representing 18% of annual terrestrial precipitation). Adjusted for local climatic conditions, global PASW storage rarely exceeds 14,853 km3 per year highlighting the need for multiple refilling of soil profiles. Differences between potential and climatic PASW are manifested primarily in arid regions (where soil profiles are rarely filled to capacity) whereas in humid regions differences in PASW storage are minor. Plain Language Summary: Plant‐available soil water (PASW) is defined as the amount of water held in soil that can be used by plants. It is conventionally estimated as the difference between field capacity (FC) and wilting point (WP), which depend on soil type and plant physiology. Water contents at FC and WP are usually deduced at fixed matric potentials irrespective of soil types (−3.3 and −150 m for FC and WP, respectively). However, FC is affected by various factors such as soil texture, soil structure, and clay type that affect the dynamics of FC attainment and put into question the use of a static definition based on constant matric potentials. Therefore, we used the approach developed by Assouline and Or (2014, https://doi.org/10.1002/2014wr015475) that considers a dynamic definition of FC based on soil‐specific matric potential values beyond which the soil water continuity is substantially reduced or disrupted. The potential PASW was calculated by subtracting the WP from the dynamic FC. The novelty of this study is to incorporate the effect of climate such as evaporative water loss to introduce a climatic PASW. Our results suggest that PASW in arid regions are overestimated when climatic effects are ignored. Key Points: Global maps of field capacity (FC) are compared based on dynamic and static definitionsLocal climate effects of evaporation and rainfall frequency via dynamic FC affect climatic plant‐available soil water (PASW)Incorporating climatic effects mainly reduces PASW in arid regions compared to humid climates [ABSTRACT FROM AUTHOR]

Understanding the evolution and maintenance of plant sexual diversity needs to incorporate both regional processes and local climate factors across large geographic scales. Using data of woody flowering plants from a global set of large-scale forest plots and multinomial logistic regression, we quantified region effects on the proportion of dioecy, monoecy, and hermaphrodite species count and abundance while incorporating evolutionary history and local climate factors. We demonstrated that plants were more likely to be dioecy than monoecy in tropical regions than in temperate regions, supporting the role of colonization processes suggested by Baker’s law in structuring the geographic patterns of plant sexual systems. We further found plants were more likely to be dioecious than monoecious in areas with younger mean species age. Plants were more likely to be hermaphrodite than dioecious in areas with high annual potential evapotranspiration and precipitation seasonality but were more likely to be dioecious than monoecious in areas with high precipitation of driest month. Our results suggest that both regional processes and local climate factors play important roles in shaping the geographic distribution of plant sexual systems, providing a baseline for predicting future changes in forest communities under global change. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) isotopes have been utilized to constrain continental weathering; however, to date, little is known about the climate effects on Mg isotope fractionation during weathering. In this study, we measured δ26Mg values of bulk regolith and exchangeable fraction in two granite regolith profiles developed under temperate, semiarid and tropical, humid climate conditions, respectively. Combined with mineralogy and element composition, we aimed to investigate how climate influences fractionation patterns of Mg isotopes during chemical weathering. At the temperate site, δ26Mg values of regolith are slightly higher than that of the bedrock and negatively correlated with τMg,Th. Correspondingly, the exchangeable Mg is characterized by low δ26Mg values. These results can be explained by the formation of small number of clay minerals. For the tropical regolith profile, δ26Mg values decrease toward the surface, and the regolith has either lower δ26Mg values above −250 cm or higher δ26Mg values below −250 cm relative to the bedrock. The δ26Mg value of exchangeable Mg is markedly lower than that of the regolith and varies significantly. These results can be explained by the mixing of Mg from solid weathering products and atmospheric deposition. The Mg from rainwater and/or marine aerosol deposit on the regolith and some may enter the crystal structure of the illite. The deposited Mg can overprint the granitic Mg, and the δ26Mg value of shallow regolith samples will reflect mixing between granitic and atmospheric sources. The compilation of our and previously published Mg isotopic data reveals the potential control of climate on Mg isotope fractionation during continental weathering. Plain Language Summary: The isotopes of magnesium (Mg) can serve as a useful tracer in understanding the chemical weathering processes of silicate rocks. Previous studies have mainly focused on Mg isotope fractionation during silicate weathering by investigating single weathering profiles that have developed under constant climate conditions; however, the impact of climate on Mg isotope fractionation during silicate weathering remains poorly understood. Here, we analyzed Mg isotope compositions in two granite regolith profiles developed under temperate (semiarid) and tropical (humid) climate conditions. Our study suggests that the patterns of Mg mobilization and Mg isotope fractionation during granite weathering differ significantly in distinct climate zones. The compilation of our and previously published Mg isotopic data reveals that climate may have a huge impact on Mg isotope fractionation during terrestrial weathering, which is of significance to interpret the Mg isotope compositions of weathering products and river waters at a global scale. Key Points: Magnesium isotope fractionation differs significantly during granite weathering in temperate and tropical climate zonesThe formation of illite results in heavy magnesium isotope enrichment in solid weathering productsAtmospheric deposition contributes a mass of light magnesium isotopes to shallow regolith under extremely weathered conditions [ABSTRACT FROM AUTHOR]

Abstract The estimation of plant‐available soil water (PASW) is essential to quantify transpiration fluxes, the onset of heatwaves, irrigation water management, land‐use decisions, vegetation ecology, and land surface memory in climate models. PASW is the amount of stored water available for plant use. It is broadly defined as the difference between soil water content at field capacity (FC) and wilting point (WP) in the root zone. The limiting states of FC and WP are linked to gravitational drainage and plant physiology and are often deduced from soil water characteristics at prescribed matric potentials (−3.3 and −150 m for FC and WP, respectively). Evidence suggests that static definition of FC at a constant matric potential ignores dynamic effects on FC attainment affected by soil and climate. Here, we revise the definition of PASW by considering (a) soil‐specific dynamic effects and (b) local climate effects of evaporation and rainfall frequency on PASW. The new global PASW maps benefit from state‐of‐the‐art soil maps, water characteristic parameterization, and incorporation of dynamic definition of FC. For completeness we provide static and dynamic PASW estimates. Globally, ice‐free soils store up to 19,941 km3 of water in the top 1 m (representing 18% of annual terrestrial precipitation). Adjusted for local climatic conditions, global PASW storage rarely exceeds 14,853 km3 per year highlighting the need for multiple refilling of soil profiles. Differences between potential and climatic PASW are manifested primarily in arid regions (where soil profiles are rarely filled to capacity) whereas in humid regions differences in PASW storage are minor.

Wetlands are one of the world's three major ecosystems. Marsh wetland vegetation, with its unique characteristics, is playing an increasingly prominent role in absorbing atmospheric carbon dioxide and mitigating climate warming. This study estimated the annual, seasonal, and monthly trends of marsh wetland vegetation net primary productivity (NPP) in China from 2005 to 2015 based on the Carnegie–Ames–Stanford approach (CASA) model. The temporal and spatial characteristics of NPP were analyzed and the driving factors were discussed. The results showed that the annual marsh wetland vegetation NPP had an increasing trend from 2005 to 2015 on national scale in China, with the lowest and highest values in 2005 (202.03 gCm−2a−1) and 2015 (222.58 gCm−2a−1), respectively. The monthly seasonal variations in marsh wetland vegetation NPP consistent with the typical growth pattern of vegetation observed in China. Monthly marsh wetland vegetation NPP showed a unimodal distribution, and May to September were the main months for NPP accumulation. The highest vegetation NPP values occurred during the summer season. Marsh wetland vegetation types did impact the NPP distribution, Gramineous marsh vegetation contributed most to the total NPP (29%). Spatially, the NPP was higher in east than in the west, and higher in the center than in the south and north. An overall positive impact of precipitation and temperature on the Chinese marsh wetland vegetation NPP was revealed. The study recommended to give greater attention the conservation of Gramineous vegetation alongside the overall protection of Chinese marsh wetlands. Our findings can offer important evaluation results and guidance for the future addressing climate change and conservation and maintenance of the carbon sink capacity of marsh wetland vegetation in China.

Climate oscillations are becoming more extreme, and mangroves may be more susceptible to changes in physical conditions that can lead to mass diebacks. The current study analysed the impacts of an extreme weather event in the Cananéia-Iguape Coastal System, southeast Brazilian mangroves and the condition of the area over three years. We used a multiproxy approach, including analyses of climatic attributes, structural vegetation, and vegetation indices. Damage caused by a strong storm and hail damage had a severe impact on mangrove areas. A meteorological station installed in the mangrove since 2008 recorded a maximum wind gust of 58 km·h−1 on 30 May 2019. On the Beaufort scale, this speed is classified as strong wind. After the extreme weather event, there were catastrophic impacts on the mangrove, with more than 90% dead trunks. Vegetation indices were reduced, indicating intense changes. The NDVI of the mangroves was reduced from 0.72 to 0.35. The LAI confirmed this premise, with a reduction from 4.25 to 0.63. After three years, natural recovery had not occurred. Extreme weather events have continued to occur along coasts, drastically altering the landscape. Mangroves have been affected by these events, and depending on the state of health of the forests, may have difficulties in recovery. [ABSTRACT FROM AUTHOR]

Introduction: cerebrovascular disease is a neurological emergency that requires immediate diagnosis and therapeutic intervention, sometimes influenced by changes in weather and climate. Objective: to describe the relationship between temperature and atmospheric pressure with admissions and deaths due to cerebrovascular disease. Methods: a cross-sectional descriptive study was developed in the "Mártires del 9 de abril" Hospital of the Sagua la Grande Municipality in the period between 1993 and 2017. The universe of hospitalized patients with this diagnosis was 3719; we worked with the population, no sample was selected. The review of individual medical records was performed with the aim of collecting data of interest related to the variables under study. The prognosis of admissions and deaths was modeled using the Objective Regression Regression methodology. Results: a statistical description of these two variables was made. The mean number of admissions was 148.7 cases, with a standard deviation of 24.9. The mean number of deaths was 35.7 with a standard deviation of 13.2. Conclusions: as the minimum temperature increases, admissions and deaths increase, so this impact is related to climate change. In the case of admissions, as atmospheric pressure increases, the number of admissions decreases. [ABSTRACT FROM AUTHOR]

The North Pacific armorhead (NPA), Pentaceros wheeleri, is thought to exhibit an extended post‐spawning epipelagic phase in which larvae disperse to the northeast Pacific Ocean. Current understanding of juvenile distribution, development, and mechanisms that drive recruitment variation, however, remains largely incomplete. The objective of this study was to compare a time series of NPA recruitment to established climate indices and to environmental covariates to explore drivers of the NPA life cycle. Additionally, this work investigates potential larval NPA transport pathways and their positional relationships to the proposed northeastern nursery grounds. Using Lagrangian particle tracking, trajectories of passive larvae were simulated at depths of 0 and 15 m for 18 years (2001–2018) from the Southern Emperor‐Northern Hawaiian Ridge (SE‐NHR) natal habitat. Dispersal distances and particle end positions were examined for their potential relationships with recruitment. Sea surface temperature and net primary productivity were evaluated as predictor variables using generalized additive modeling. Neither regression of particle end‐point characteristics nor environmental covariates resulted in significant correlations with recruitment here, perhaps owing to data limitations surrounding the nursery zone. Particles were found to be advected largely within the North Pacific transition zone in the central north Pacific. Significant seasonal correlations were found between recruitment and the Arctic Oscillation, Pacific Decadal Oscillation and North Pacific Gyre Oscillation, suggesting that NPA recruitment mechanisms respond to interannual ocean‐atmospheric climate oscillations. Better knowledge of the connections between recruitment and the environment would be valuable for stock management, and improvements for advection predictions are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Climate change mitigation trade-offs between increasing harvests to exploit substitution effects versus accumulating forest carbon sequestration complicate recommendations for climate beneficial forest management. Here, a time dynamic assessment ascertains climate change mitigation potential from different rotation forest management alternatives across three Swedish regions integrating the forest decision support system Heureka RegWise with a wood product model using life cycle assessment data. The objective is to increase understanding on the climate effects of varying the forest management. Across all regions, prolonging rotations by 20% leads on average to the largest additional net climate benefit until 2050 in both, saved emissions and temperature cooling, while decreasing harvests by 20% leads to the cumulatively largest net climate benefits past 2050. In contrast, increasing harvests or decreasing the rotation period accordingly provokes temporally alternating net emissions, or slight net emission, respectively, regardless of a changing market displacement factor. However, future forest calamities might compromise potential additional temperature cooling from forests, while substitution effects, despite probable prospective decreases, require additional thorough and time explicit assessments, to provide more robust policy consultation. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau is generally referred to as the Chinese water tower, and evapotranspiration (ET) affects the water budget and stability of alpine meadows on the Tibetan Plateau. However, its variability and controlling mechanisms have not been well documented under the drier conditions induced by global warming. Therefore, this study aimed to clarify whether meteorological or biological factors primarily affected the variability in ET under contrasting water conditions in the alpine meadow ecosystem on the Tibetan Plateau. Based on 6-year (2013–2018) eddy covariance observations and the corresponding meteorological and biological data, linear perturbation analyses were employed to isolate the contributions of meteorological and biological factors to the variability in evapotranspiration (δET). The results showed that δET was mainly driven by meteorological factors in wet peak seasons (July and August), and was dominated by net radiation (Rn) and air temperature (Ta), indicating that the inadequate available energy is the factor limiting ET. However, the dominant factors affecting δET shifted from meteorological to biological in dry peak seasons when the canopy stomatal conductance (gs) and leaf area index were dominant. At this point, the ecosystem was limited by the water conditions. These results provide empirical insights into how meteorological and biological factors regulate variability in ET under contrasting water conditions. These findings can further improve our understanding of water cycle processes and can help effectively manage water resources in alpine meadow ecosystems under future climate change conditions. [ABSTRACT FROM AUTHOR]

Abstract Both the Norwegian Spring Spawning herring (Clupea harengus) and the Northeast Arctic (NEA) cod (Gadus morhua) are examples of strong stock reduction and decline of the associated fisheries due to overfishing followed by a recovery. Cod and herring are both part of the Barents Sea ecosystem, which has experienced major warming events in the early (1920–1940) and late 20th century. While the collapse or near collapse of these stocks seems to be linked to an instability created by overfishing and climate, the difference of population dynamics before and after is not fully understood. In particular, it is unclear how the changes in population dynamics before and after the collapses are associated with biotic interactions. The combination of the availability of unique long‐term time series for herring and cod makes it a well‐suited study system to investigate the effects of collapse. We examine how species interactions may differently affect the herring and cod population dynamic before and after a collapse. Particularly we explore, using a GAM modeling approach, how herring could affect cod and vice versa. We found that the effect of cod biomass on herring that was generally positive (i.e., covariation) but the effect became negative after the collapse (i.e., predation or competition). Likewise a change occurred for the cod, the juvenile herring biomass that had no effect before the collapse had a negative effect after. Our results indicate that the population collapses may alter the inter‐specific interactions and response to abiotic environmental changes. While the stocks are at similar abundance levels before and after the collapses, the system is potentially different in its functioning and may require different management action.

Climate oscillations are becoming more extreme, and mangroves may be more susceptible to changes in physical conditions that can lead to mass diebacks. The current study analysed the impacts of an extreme weather event in the Cananéia-Iguape Coastal System, southeast Brazilian mangroves and the condition of the area over three years. We used a multiproxy approach, including analyses of climatic attributes, structural vegetation, and vegetation indices. Damage caused by a strong storm and hail damage had a severe impact on mangrove areas. A meteorological station installed in the mangrove since 2008 recorded a maximum wind gust of 58 km·h−1 on 30 May 2019. On the Beaufort scale, this speed is classified as strong wind. After the extreme weather event, there were catastrophic impacts on the mangrove, with more than 90% dead trunks. Vegetation indices were reduced, indicating intense changes. The NDVI of the mangroves was reduced from 0.72 to 0.35. The LAI confirmed this premise, with a reduction from 4.25 to 0.63. After three years, natural recovery had not occurred. Extreme weather events have continued to occur along coasts, drastically altering the landscape. Mangroves have been affected by these events, and depending on the state of health of the forests, may have difficulties in recovery.

Pavement temperature is one of the most important factors influencing the performance of flexible pavements. The major components of the Earth's heat balance system are downwelling shortwave radiation (D-SWR) from the sun, downwelling longwave radiation (D-LWR) from the atmosphere, and upwelling longwave radiation (U-LWR) emitted by the warm pavement surface. The Pavement ME Design (PMED) software (AASHTO, 2015. Mechanistic-empirical pavement design guide–a manual of practice. Washington, DC: AASHTO) computes temperature distributions in the pavement over depth and time using algorithms originally proposed by Dempsey et al. (1985. Environmental effects on pavements: theory manual. US Department of Transportation, Federal Highway Administration). These algorithms are largely empirical, depend heavily on imprecise corrections for cloud cover, and in some parts contradict atmospheric physics. Improved models for the major radiation components proposed here include: (1) D-SWR values modelled by the MERRA-2 climate re-analysis product from NASA (Rienecker et al., 2011. MERRA: NASA's modern-era retrospective analysis for research and applications. Journal of Climate, 24, 3624–3648); (2) D-LWR modelled using the Idso (1981. A set of equations for full spectrum and 8-to 14-μm and 10.5-to 12.5-μm thermal radiation from cloudless skies. Water Resources Research, 17, 295–304) empirical parameterisation with a physics-consistent adjustment for cloud cover; and (3) U-LWR calculations without the physics-inconsistent cloud cover adjustment embedded in PMED. The D-SWR and D-LWR radiation models were evaluated via comparisons against ground-based radiation observations at 21 locations in the Solar Infrared Radiations Stations (SIRS) database. The MERRA-2 estimates of D-SWR, although not perfect, were found to agree substantially better than the current PMED models with the ground truth SIRS. The D-LWR fluxes from the Idso (1981. A set of equations for full spectrum and 8-to 14-μm and 10.5-to 12.5-μm thermal radiation from cloudless skies. Water Resources Research, 17, 295–304) parameterisation were also found to agree substantially better than the current PMED with the ground truth SIRS, with particularly striking improvements for the all-sky (i.e. including clouds) condition. A limited series of flexible pavement performance analyses were conducted to illustrate the potential practical impact of these radiation model changes. The new radiation models produced significantly higher pavement temperatures that lead to substantially higher total rutting, asphalt rutting, and bottom up fatigue cracking. These changes in distress magnitudes must be evaluated in qualitative terms only, as all analyses used the same field calibration coefficients for the distress models. The primary conclusion from this work is that the current radiation models incorporated in PMED are inaccurate and, in some cases, inconsistent with fundamental atmospheric physics. This can have significant impacts on predicted pavement performance. It is recommended that the current PMED radiation models be replaced by the new D-SWR, D-LWR, and U-LWR. New field calibration of the empirical distress models would be required after incorporating the new radiation models. [ABSTRACT FROM AUTHOR]

Wuhan has witnessed unprecedented urban expansion that encroached upon sizable inland lakes. However, the impacts of urban expansion on climate and heat stress for such a city with complex physiographic background (land‐water mosaics) remain understudied. Using a coupled urban‐lake‐atmospheric model, we first examined summer climate responses to urban expansion and lake shrinkage in Wuhan during 2000–2020. Second, multiple heat stress indicators were used to evaluate human thermal comfort in different contexts of interest. Results showed that the presence of water bodies reduced daytime maximum temperature, raised nighttime minimum temperature, and increased moisture content in urban and built‐up areas. Urban expansion alone led to summer warming of 0.9°C and drying of 0.9 g/kg, with local peak warming and drying up to 2°C and 1.4 g/kg. In comparison, urban expansion with lake shrinkage showed a reduced magnitude of warming of 0.8°C and increased magnitude of drying of 1.6 g/kg, with the maximum changes up to 1.4°C and 2.0 g/kg. The presence of water bodies reduced while urban expansion increased the frequency of occurrence of yellow and orange heat alert days; however, both increased the number of days exerting high thermal risks on outdoor workers and those days that were dangerous for outdoor pedestrians. Our study underlined that both urban expansion and water body existence exerted a strong influence on summer climate and heat stress in Wuhan, and highlighted that mitigation measures should be taken to alleviate the deleterious impacts of high temperature and humidity on human health. Key Points: High‐resolution simulations with a coupled urban‐lake‐atmospheric model in a rapidly urbanizing and land‐water mosaic areaUrban expansion with lake shrinkage led to reduced magnitude of warming but enlarged magnitude of drying compared to pure urban expansionTemperature and humidity were equally important to affect human thermal comfort of different contexts of interest in Wuhan [ABSTRACT FROM AUTHOR]

The Tension Zone (TZ) is a prominent Midwestern ecotone where the flora of two major forest types (Northern Mixed Forests and Southern Broadleaf Forests) commingle, striking diagonally across the states of Wisconsin and Minnesota. Here, we evaluated the TZ's original placement as demarcated by previous scholars relative to the synecological and autecological characteristics of witness trees from US Public Land Survey records. Witness trees were categorized by temperature and fire relations, point data analyzed in GIS, and spatial outputs compared with the original TZ. Our temperature-based line, representing temperature relations of witness trees, generally corresponded with the original TZ. However, in the lee of firebreaks, isolated pockets of cool/cold mesophytic genera occurred south of the TZ, indicating that other environmental factors were involved in TZ expression. A pyrogenic-based line, created by classifying witness trees by fire relations, had two major northward departures from the original TZ where cold-adapted yet pyrophilic northern pines occurred on sandy glacial deposits. Fire was found to play a contributing role, being pervasive south of the TZ, whereas edaphically restricted to dry, sandy landscapes to the north. Climate change and fire suppression will exert future "tension" on the line, forcing uncertain movement across the landscape from these two divergent forces, with projected higher future temperatures pushing the TZ northward and fire suppression and accompanying mesophication (comprised of primarily cool/cold–based trees) pulling the TZ southward. An endpoint to the temperate-based Midwestern TZ was identified in northwest Minnesota, converting over to a Boreal-Prairie TZ northward. [ABSTRACT FROM AUTHOR]

Copyright of Revista Jurídica (0103-3506) is the property of Revista Juridica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

On the one hand, one of the main obstacles to the photovoltaic (PV) power production is the presence of dust in the atmosphere, which prevents sunlight from reaching the surface of PV modules. On the other hand, the economic operation of PV power plants largely depends on cleaning of dust particles settled on the module surface. In this study, a comprehensive review of experimental (field) studies conducted in different parts of the world is presented to investigate the effect of different climates on the natural and artificial dust particle deposition on the modules surface. The different geographical climates have different potentials for dust production. Some regions such as North Africa, North China, and the Middle East act as a source and transport the generated dust to all parts of the world. Therefore, even areas with less potential for dust generation can be exposed to emitted dust from the sources. This study describes the effect of important factors in dust settlement on the PV module surface such as relative humidity, rainfall, and gravity. The reduction in the power production capacity of PV modules installed in different parts of the world due to dust deposition on their surface was compared and discussed. Furthermore, some studies, which used the artificial particle, i. e. the particles produced from urban pollution sources such as industrial pollutants and vehicular exhaust smoke were also reviewed. [ABSTRACT FROM AUTHOR]

The risk of heatwave events and their persistence has intensified in recent past and is expected to increase faster in future. However, the anticipated changes in socioeconomic exposure to heatwaves are still unexplored. Here, we investigate the projected heat stress and associated socioeconomic exposure across South Asia (SA) and its subregions using the newly released ensemble mean of 23 global climate models from the Coupled Model Intercomparison Project Phase 6 (CMIP6), population, and Gross Domestic Product (GDP) projections. We used two Shared Socioeconomic Pathways (SSPs), namely SSP2‐4.5 and SSP5‐8.5, and three‐time periods, that is, near‐term, midterm, and long‐term relative to the base period (1985–2005). We found that SA region has the potential for widespread changes to Wet bulb globe temperature (WBGT) of 6.5°C, which can exceed the theoretical limits of human tolerance by the mid of 21st century. The SA population's exposure significantly increases during midterm and long‐term periods by ∼750×106 $750\times {10}^{6}$ person‐hours under the SSP5‐8.5 scenario. The GDP exposure is the greatest for the same period's up to 200×109 $200\times {10}^{9}$ dollar‐hours under the SSP2‐4.5. Moreover, the foothills Himalayans and northern parts of Pakistan are presently unaffected by WBGT during midterm and long‐term periods under both scenarios. Among subregions (hereafter R1, R2, R3, and R4), the frequency of subdaily WBGT is projected to increase in the region R2 and R4 by ∼70% and ∼90% under the SSP2‐4.5 and SSP5‐8.5 scenarios relative to the base period. The highest upsurge in exposure is anticipated for R2, including southern Pakistan and southwestern India, followed by R1 and R3. Notably, the climate effect is more dominant than the population, whereas changes in GDP effect contribute to the total change in GDP exposure. Plain Language Summary: SA is one of the hotspot regions to the climatic extremes where the earliest exposure to heat waves is expected in future warmer climates. We show that the SA population is highly exposed to subdaily WBGT for midterm and long‐term periods. In contrast, the robust change in GDP exposure appeared for the same periods under SSP2‐4.5 and SSP5‐8.5. In contrast, relatively less frequent WBGT exhibited over foothills Himalayans and northern parts of Pakistan. Still, the spatial magnitude of WBGT is more likely to be intensified by the end of the 21st century. Regarding regional aggregate changes, R2 and R4 are anticipated to upsurge in subdaily WBGT relative to the base period under SSP2‐4.5 and SSP5‐8.5 scenarios. We also found that southern Pakistan and south‐northern India are projected to increase exposure to heat stress, followed by R1 and R3. Overall, the projected changes in exposure are mainly due to the interaction effect accounted for ∼650 (800) × 106 person‐hours under SSP2‐4.5/SSP2 and SSP5‐8.5/SSP5 scenarios. It can be inferred that the climate influence is more dominant than the population, particularly for southwestern Pakistan and most parts of India. Key Points: The region of South Asia experiences widespread changes to Wet bulb globe temperature of 6.5°CThe spatial magnitude of Wet bulb globe temperature is likely to be intensified by the end of the 21st centuryProjected changes in socioeconomic exposure are mainly due to the interaction effect under Shared Socioeconomic Pathways [ABSTRACT FROM AUTHOR]

This review presents how the boreal and the tropical forests affect the atmosphere, its chemical composition, its function, and further how that affects the climate and, in return, the ecosystems through feedback processes. Observations from key tower sites standing out due to their long-term comprehensive observations: The Amazon Tall Tower Observatory in Central Amazonia, the Zotino Tall Tower Observatory in Siberia, and the Station to Measure Ecosystem-Atmosphere Relations at Hyytiäla in Finland. The review is complemented by short-term observations from networks and large experiments. The review discusses atmospheric chemistry observations, aerosol formation and processing, physiochemical aerosol, and cloud condensation nuclei properties and finds surprising similarities and important differences in the two ecosystems. The aerosol concentrations and chemistry are similar, particularly concerning the main chemical components, both dominated by an organic fraction, while the boreal ecosystem has generally higher concentrations of inorganics, due to higher influence of long-range transported air pollution. The emissions of biogenic volatile organic compounds are dominated by isoprene and monoterpene in the tropical and boreal regions, respectively, being the main precursors of the organic aerosol fraction. Observations and modeling studies show that climate change and deforestation affect the ecosystems such that the carbon and hydrological cycles in Amazonia are changing to carbon neutrality and affect precipitation downwind. In Africa, the tropical forests are so far maintaining their carbon sink. It is urgent to better understand the interaction between these major ecosystems, the atmosphere, and climate, which calls for more observation sites, providing long-term data on water, carbon, and other biogeochemical cycles. This is essential in finding a sustainable balance between forest preservation and reforestation versus a potential increase in food production and biofuels, which are critical in maintaining ecosystem services and global climate stability. Reducing global warming and deforestation is vital for tropical forests. [ABSTRACT FROM AUTHOR]

Marshes bordering rivers and estuaries are productive ecosystems that interact dynamically with the adjacent water mass. This is a multi-year study (2019-2022) of seasonal changes in the density of naked amoebae in monthly samples from the surface water of the Hudson estuary near Piermont, N. Y. with relationships to key environmental variables (surface water temperature, salinity, Secchi depth representing turbidity, and enterococcus bacterial counts). During the colder months (November to March), when decayed leaves and litter from the deciduous marsh grass produced organic matter in the sediment surface, the mean abundance of active amoebae ± standard error of the mean (SEM) was higher (3.07 ± 0.99 × 104/L, N = 7). In warmer months (May to September) the abundance of amoebae was lower (1.35 ± 0.29 × 104 / L, N = 10). A multivariate linear regression analysis was performed relating amoeba abundance to four major water mass variables, resulting in the following statistically significant equation (p = 0.03): AD = 0.121 × T + 0.301 × L - 0.047 × S + 0.359 × C, where: AD = active amoebae density (× 104/L), T = temperature (oC), L = tide level (m), S = Secchi disc depth (cm) and C = bacterial enterococcus concentration (number/ml). In general, given the increasing evidence of the potential importance of amoeboid protists in aquatic ecosystems, further research is warranted on their role in food webs and the carbon biogeochemical cycle within heterotrophic estuarine and coastal waters. [ABSTRACT FROM AUTHOR]

Climate change is associated with more intense phases of heat, drought or precipitation that can have a negative impact on soil properties. Our goal was to understand if elevated CO2 (eCO2) and temperature (eT), and a multicomponent (eCO2eT) climate effect will influence soil properties from cereal‐legume intercrops differently compared to sole crops. We hypothesized that cereal‐legume intercrops can regulate climate effects, causing soil properties and greenhouse gas fluxes to be similar to ambient climate conditions. eT and eCO2eT decreased soil organic carbon (C) (p =.001) and nitrogen (N) (p =.003) but increased (p =.011) soil nitrate in all crop systems, compared to ambient conditions. For crop systems, soil ammonium was lower (p =.001) with all climate effects, but nitrate was greater (p =.011) with eCO2 and eCO2eT compared to ambient conditions. The microbial community had a preferential (p =.024) consumption of C3 sources in the sole crops. Climate effects also influenced how C and N were accessed by microbes in all crop systems, shifting (p =.001) species richness and microbial community structure. CO2 fluxes were greater (p =.001) with eT and eCO2, whereas N2O fluxes were greater (p =.005) with eCO2 and eCO2eT. However, greenhouse gas fluxes from the intercrop were similar between eT or eCO2eT and ambient conditions. For soil properties, we rejected our hypothesis since cereal‐legume intercrops did not have an advantage over sole crops to cope with single‐ and multicomponent climate effects, but we partially accepted our hypothesis since greenhouse gas fluxes were similar between AMB and eT or eCO2eT. [ABSTRACT FROM AUTHOR]

This review presents how the boreal and the tropical forests affect the atmosphere, its chemical composition, its function, and further how that affects the climate and, in return, the ecosystems through feedback processes. Observations from key tower sites standing out due to their long-term comprehensive observations: The Amazon Tall Tower Observatory in Central Amazonia, the Zotino Tall Tower Observatory in Siberia, and the Station to Measure Ecosystem-Atmosphere Relations at Hyytiäla in Finland. The review is complemented by short-term observations from networks and large experiments. The review discusses atmospheric chemistry observations, aerosol formation and processing, physiochemical aerosol, and cloud condensation nuclei properties and finds surprising similarities and important differences in the two ecosystems. The aerosol concentrations and chemistry are similar, particularly concerning the main chemical components, both dominated by an organic fraction, while the boreal ecosystem has generally higher concentrations of inorganics, due to higher influence of long-range transported air pollution. The emissions of biogenic volatile organic compounds are dominated by isoprene and monoterpene in the tropical and boreal regions, respectively, being the main precursors of the organic aerosol fraction. Observations and modeling studies show that climate change and deforestation affect the ecosystems such that the carbon and hydrological cycles in Amazonia are changing to carbon neutrality and affect precipitation downwind. In Africa, the tropical forests are so far maintaining their carbon sink. It is urgent to better understand the interaction between these major ecosystems, the atmosphere, and climate, which calls for more observation sites, providing long-term data on water, carbon, and other biogeochemical cycles. This is essential in finding a sustainable balance between forest preservation and reforestation versus a potential increase in food production and biofuels, which are critical in maintaining ecosystem services and global climate stability. Reducing global warming and deforestation is vital for tropical forests.

Abstract The risk of heatwave events and their persistence has intensified in recent past and is expected to increase faster in future. However, the anticipated changes in socioeconomic exposure to heatwaves are still unexplored. Here, we investigate the projected heat stress and associated socioeconomic exposure across South Asia (SA) and its subregions using the newly released ensemble mean of 23 global climate models from the Coupled Model Intercomparison Project Phase 6 (CMIP6), population, and Gross Domestic Product (GDP) projections. We used two Shared Socioeconomic Pathways (SSPs), namely SSP2‐4.5 and SSP5‐8.5, and three‐time periods, that is, near‐term, midterm, and long‐term relative to the base period (1985–2005). We found that SA region has the potential for widespread changes to Wet bulb globe temperature (WBGT) of 6.5°C, which can exceed the theoretical limits of human tolerance by the mid of 21st century. The SA population's exposure significantly increases during midterm and long‐term periods by ∼750×106 $750 imes {10}^{6}$ person‐hours under the SSP5‐8.5 scenario. The GDP exposure is the greatest for the same period's up to 200×109 $200 imes {10}^{9}$ dollar‐hours under the SSP2‐4.5. Moreover, the foothills Himalayans and northern parts of Pakistan are presently unaffected by WBGT during midterm and long‐term periods under both scenarios. Among subregions (hereafter R1, R2, R3, and R4), the frequency of subdaily WBGT is projected to increase in the region R2 and R4 by ∼70% and ∼90% under the SSP2‐4.5 and SSP5‐8.5 scenarios relative to the base period. The highest upsurge in exposure is anticipated for R2, including southern Pakistan and southwestern India, followed by R1 and R3. Notably, the climate effect is more dominant than the population, whereas changes in GDP effect contribute to the total change in GDP exposure.

Espírito Santo state, in Brazil, is a dengue-endemic region predicted to suffer from an increase in temperature and drought due to climate change, which could affect the areas with active dengue virus transmission. The study objective was modeling climatic factors and climate change effects in zones suitable for dengue virus transmission in Espírito Santo state, Brazil. Data on dengue reports from 2022 were used to determine climatic variables related to spatial distribution. The climate change projections were generated for the 2030s, 2050s, 2070s, and 2090s for three distinct Shared Socioeconomic Pathways: SSP1-2.6, SSP2-4.5 and SSP5-8.5. A maximum entropy algorithm was used to construct the three models and projections, and the results were used to calculate the ensemble mean. Isothermality, the maximum temperature of the warmest month, precipitation of the wettest month, precipitation of the warmest quarter, and annual precipitation impacted the model. Projections indicated a change in areas suitable for dengue virus transmission, varying from -30.44% in the 2070s (SSP1-2.6) to +13.07% in the 2070s (SSP5-8.5) compared to 2022. The coastal regions were consistently suitable in all scenarios. Urbanized and highly populated areas were predicted to persist with active dengue transmission in Espírito Santo state, posing challenges for public health response., (© The Author(s) 2024. Published by Oxford University Press.)

Both the Norwegian Spring Spawning herring (Clupea harengus) and the Northeast Arctic (NEA) cod (Gadus morhua) are examples of strong stock reduction and decline of the associated fisheries due to overfishing followed by a recovery. Cod and herring are both part of the Barents Sea ecosystem, which has experienced major warming events in the early (1920–1940) and late 20th century. While the collapse or near collapse of these stocks seems to be linked to an instability created by overfishing and climate, the difference of population dynamics before and after is not fully understood. In particular, it is unclear how the changes in population dynamics before and after the collapses are associated with biotic interactions. The combination of the availability of unique long‐term time series for herring and cod makes it a well‐suited study system to investigate the effects of collapse. We examine how species interactions may differently affect the herring and cod population dynamic before and after a collapse. Particularly we explore, using a GAM modeling approach, how herring could affect cod and vice versa. We found that the effect of cod biomass on herring that was generally positive (i.e., covariation) but the effect became negative after the collapse (i.e., predation or competition). Likewise a change occurred for the cod, the juvenile herring biomass that had no effect before the collapse had a negative effect after. Our results indicate that the population collapses may alter the inter‐specific interactions and response to abiotic environmental changes. While the stocks are at similar abundance levels before and after the collapses, the system is potentially different in its functioning and may require different management action. [ABSTRACT FROM AUTHOR]

Foliar nutrient concentrations, contents, and ratios are important indicators for the nutritional status of trees. They depend on the availability of nutrients and the uptake capacities of the trees, which are controlled by forest structure, soil and climate condition. Consequently, accounting for climate conditions can aid the interpretation of foliar chemistry measurements.We applied a moving-window approach to identify the effects of atmospheric temperature and precipitation on tree nutrition at different time intervals based on data collected by institutions of the German Federal States within the ICP Forests Level II network. We studied the main nutrients N, P, K, Ca, and Mg as well as foliar mass for the main temperate tree species (European beech, temperate oaks, Norway spruce, Scots pine).Results show that foliar traits of all main tree species are affected by either current and/or lagged climate condition. Nutrient concentrations are generally less sensitive to climate condition than foliar mass and nutrient contents. Nutrient contents show the same response direction to climate condition as foliar mass, while nutrient concentrations mostly show an opposite response, potentially indicating the existence of dilution effects. Only Ca content in spruce shows weak effects of climate as changes in foliar mass are entirely counterbalanced by opposing changes in Ca concentrations.For spruce, pine, and oak significant climate effects on nutrient ratios were found. In general, N:P, N:K, and P:K are less sensitive to climate variations than ratios including Mg or Ca. In beech, all nutrient concentrations show a similar response to climate condition. Nutrient ratios in beech are thus relatively robust against climate condition compared to concentrations and contents.Our results highlight that intervals of less than three month provide a good indication of the climatic impact on tree nutrition. Longer periods, or means over several years, are less suitable as indicators. Defined periods show, however, a significant role of climate beside soil factors and species on foliar nutrition and should therefore be considered for the interpretation of tree nutrition.

This paper compares the predicted distresses (via in the AASHTOWare Pavement ME Design software (PMED)) of asphalt concrete (AC) and jointed plain concrete pavement (JPCP) using four different climate data sources. These sources also include the Modern Era Retrospective Analysis for Research and Application (MERRA) Versions 1.0 and 2.0 (MERRA-1 and MERRA-2). Pavement performance predictions generated using these data showed disagreement among some of the climate data sources, especially for MERRA-2. Comprehensive diurnal and other time-series analyses of the raw climate data found significant disagreements in the percent sunshine estimates. Percent sunshine is used in the PMED environmental effects model to semi-empirically estimate the downwelling shortwave radiation reaching the pavement surface. Both MERRA data (MERRA -1 and MERRA-2) independently provide direct predictions of downwelling surface shortwave radiation (SSR). The direct model predictions of SSR were used to back calculate 'synthetic' per cent sunshine for input into the PMED. The use of the synthetic per cent sunshine derived from the predicted SSR eliminated nearly all discrepancies in the predicted pavement performance using MERRA-1 versus MERRA-2 data. Based on these results, the authors recommend that SSR rather than per cent sunshine be used as a direct input to the PMED. [ABSTRACT FROM AUTHOR]

East Asia (EA) has always been a highly concern region for human-induced climate change. In this study, a well-developed regional model RegCM4 is employed to investigate the influences of major anthropogenic aerosol (MAA, including sulfate and primary carbonaceous aerosols) variations from 2007 to 2020 on East Asian climates in winter. Results indicate that high MAA loadings in EA in winter mainly appear in Central to Eastern China. In most area of Asia (5°-55°N, 70°-140°E), the multi-year (2007–2020) mean instantaneous direct and total effective radiative forcing (IDRF and ERF) induced by MAAs are −4.22 and −3.90 W·m−2 at the surface in winter, which are 2.29 and 1.96 times of those at the tropopause. In polluted area from southwest to center China (SWCC, 27–33°N, 102–115°E), these forcings are much stronger, which causes a dimmer, cooler and drier surface and further stabilizes the lower atmosphere. The multi-year mean sunshine duration, surface air temperature, precipitation, and boundary layer thickness are changed by −20.32 min·d−1, −0.33 K, −0.08 mm·d−1, and −12.51 m, respectively in SWCC in winter. Both the aerosol surface IDRF and ERF are weakened by above 30% in SWCC in winter since the Action Plan for Air Pollution Prevention and Control was carried out, which results in less surface dimming and cooling by 9.4 min·d−1 and 0.23 K, respectively. During the most outbreak period in COVID-19 epidemic, the aerosol surface IDRF is weakened by approximately 46.87% compared to that before 2013 in SWCC, which may offset the aerosol cooling effect by 0.28 K. • Effects of emission reductions on the ARi and ACi are investigated in East Asia in winter. • ARi and ACi in East Asia in winter likely cause a cooler and drier surface, and a more stable PBL. • The aerosol cooling effect in East Asia in winter is weakened since APPCAP/COVID-19. [ABSTRACT FROM AUTHOR]

• Decrease of suspended sediment transport in the Mediterranean over the last century. • Time series reconstruction using artificial intelligence. • Crucial role of climate change in the regulation of suspended sediment transport. • Secondary influences of the anthropic impact. The analysis of suspended sediment transport and of its variations over time is crucial for understanding environmental evolution and it is the key to future challenges caused by current global warming. The Mediterranean area is a hot spot for global changes, and the variation of precipitation amount and intensity will modify the environment of this region. In this work, we analyse the time series of suspended sediment transport of two rivers located in central Italy by using statistical and artificial intelligence techniques. Our study aims to re-analyze time series of suspended sediment transport, in order to demonstrate that climate change is responsible for the substantial decrease in the amount of sediment over the past century, in relation to the atmospheric teleconnections of the North Atlantic. Anthropic pressures like reforestation, land use change, and dam building have influenced the sediment transport capacity of rivers, causing a reduction of sediment concentration in water. These results are key factors to determine the future management of the Mediterranean areas, where the future scenarios predict a greater drop in yearly precipitation, and therefore a possible further decrease in the sediment transport capacity of the rivers, with major consequences for coastal and fluvial environments. [ABSTRACT FROM AUTHOR]

Abstract Evapotranspiration (ET) plays an important role in land‐atmosphere coupling of energy, water, and carbon cycles. Following deforestation, ET is typically observed to decrease substantially as a consequence of decreases in leaf area and roots and increases in runoff. Changes in ET (latent heat flux) revise the surface energy and water budgets, which further affects large‐scale atmospheric dynamics and feeds back positively or negatively to long‐term forest sustainability. In this study, we used observations from a recent synthesis of 29 pairs of adjacent intact and deforested FLUXNET sites to improve model parameterization of stomatal characteristics, photosynthesis, and soil water dynamics in version 1 of the Energy Exascale Earth System Model (E3SM) Land Model (ELMv1). We found that default ELMv1 predicts an increase in ET after deforestation, likely leading to incorrect estimates of the effects of deforestation on land‐atmosphere coupling. The calibrated model accurately represented the FLUXNET observed deforestation effects on ET. Importantly, the search for global optimal parameters converged at values consistent with recent observational syntheses, confirming the reliability of the calibrated physical parameters. Applying this improved model parameterization to the globe scale reduced the bias of annual ET simulation by up to ~600 mm/year. Analysis on the roles of parameters suggested that future model development to improve ET simulation should focus on stomatal resistance and soil water‐related parameterizations. Finally, our predicted differences in seasonal ET changes from deforestation are large enough to substantially affect land‐atmosphere coupling and should be considered in such studies.