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This letter raises the possibility that ergodicity concerns might have some bearing on the signal‐to‐noise paradox. This is explored by applying the ergodic theorem to the theory behind ensemble weather forecasting and the ensemble mean. Using the ensemble mean as our best forecast of observations amounts to interpreting it as the most likely phase‐space trajectory, which relies on the ergodic theorem. This can fail for ensemble forecasting systems if members are not perfectly exchangeable with each other, the averaging window is too short and/or there are too few members. We argue these failures can occur in cases such as the winter North Atlantic Oscillation (NAO) forecasts due to intransitivity or regime behaviour for regions such as the North Atlantic and Arctic. This behaviour, where different ensemble members may become stuck in different relatively persistent flow states (intransitivity) or multi‐modality (regime behaviour), can in certain situations break the ergodic theorem. The problem of non‐ergodic systems and models in the case of weather forecasting is discussed, as are potential mitigation methods and metrics for ergodicity in ensemble systems. [ABSTRACT FROM AUTHOR]

Flash droughts (FDs) are distinguished by a rapid development associated with strong precipitation deficits and/or increases in atmospheric evaporative demand in the short‐term, but little is known about the atmospheric conditions underlying these events. In this study, we analyse for the first time the atmospheric dynamics involved in the development of FDs in Spain over the period 1961–2018. FDs are related to large‐scale atmospheric circulation patterns affecting the region, in particular with the positive phase of the North Atlantic Oscillation (NAO). The NAO is the main atmospheric driver of FDs in winter and autumn, and it is essential in explaining FD development in spring. We also found that FDs are typically linked to strong positive anomalies in 500 hPa geopotential height and sea level pressure over the region during the weeks prior to the onset. At the synoptic scale, the most common weather types (WTs) recorded during the development of FDs are Anticyclonic Western (ANT_W_AD), East (E_AD) and Northeast (NE_AD) advection, and Anticyclonic (ANTICYC). In particular, ANTICYC WT is the main atmospheric driver of FDs in summer. Ridging conditions occur frequently during FDs in all seasons, being the most important factor controlling FD development in spring. Likewise, we noted that some of the FDs recorded in summer are related to and/or exacerbated by Saharan air intrusions associated with pronounced ridges. The results of this research have important implications for the understanding, monitoring and prediction of FDs in Spain, providing a detailed assessment of the main atmospheric dynamics involved in FD triggering at different spatial scales. [ABSTRACT FROM AUTHOR]

This systematic review, based on an adaptation of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement from 2020, focuses on studies of the atmospheric mechanisms underlying extreme precipitation events in mainland Portugal, as well as observed trends and projections. The 54 selected articles cover the period from 2000 to 2024, in which the most used keywords are "portugal" and "extreme precipitation". Of the 54, 23 analyse trends and climate projections of precipitation events, confirming a decrease in total annual precipitation, especially in autumn and spring, accompanied by an increase in the frequency and intensity of extreme precipitation events in autumn, spring and winter. Several articles (twelve) analyse the relationship between synoptic-scale circulation and heavy precipitation, using an atmospheric circulation types approach. Others (two) establish the link with teleconnection patterns, namely the North Atlantic Oscillation (NAO), and still others (three) explore the role of atmospheric rivers. Additionally, five articles focus on evaluating databases and Numerical Weather Prediction (NWP) models, and nine articles focus on precipitation-related extreme weather events, such as tornadoes, hail and lightning activity. Despite significant advances in the study of extreme precipitation events in Portugal, there is still a lack of studies on hourly or sub-hourly scales, which is critical to understanding mesoscale, short-lived events. Several studies show NWP models still have limitations in simulating extreme precipitation events, especially in complex orography areas. Therefore, a better understanding of such events is fundamental to promoting continuous improvements in operational weather forecasting and contributing to more reliable forecasts of such events in the future. [ABSTRACT FROM AUTHOR]

Abstract The construction of sub‐daily pressure series is described for the cities of London (GB) and Paris (FR). The series extend back 1692 and 1748, respectively, and as such they represent two of the longest sub‐daily series of barometric pressure available. These series are updated from the previously documented London and Paris daily series and offer more homogeneous series, and in the case of the London series a more temporally complete sequence of data. A pairwise homogenization procedure has been applied to the two series alongside the long series of pressure that exists for De Bilt (NL). The De Bilt series has been available for some time in the International Surface Pressure Dataset (ISPD), but further quality control and homogeneity‐checking procedures have been applied to the data in this paper and therefore the three series are released together in this dataset. The series are of immediate interest for understanding changes to storm activity across the English Channel and North Atlantic region over an extended timeframe but may also be assimilated into reanalysis datasets such as the 20th‐century reanalysis.

This study investigates the long-term temporal patterns of sea level changes by analyzing monthly tide gauge data from 1950 to 2022 (42 to 72 years) along the European coastline and monthly altimetry data from 1992 to 2024 in the surrounding European seas. The primary focus is on signals with periods longer than 5 years. The application of wavelet-based approaches and multiresolution analysis has enabled the isolation of signals with periods of approximately 8 and 16 years. However, the latter has only been observed in tide gauge data, as the altimetry time series is not sufficiently long. The same analysis was applied to the North Atlantic Oscillation (NAO) and Atlantic Multidecadal Oscillation (AMO) indices, which enabled the detection of the same signals. The reported multiyear signals of sea level are correlated with NAO and AMO indices, particularly during the period spanning from 1975 to 2010. [ABSTRACT FROM AUTHOR]

The North Atlantic Oscillation (NAO) and North Atlantic tripole sea surface temperature (SST_tri) are important modes in the atmosphere and ocean over the North Atlantic, respectively. The link between the two is well‐known. However, this link weakened during 1980–2001, which is particularly pronounced in late winter and was not detected in early winter. This phenomenon has not been well revealed. The role of NAO in the above correlation changes was discussed. In late winter, a significant eastward shift (up to 20° longitude) of NAO south center during 1980–2001 was observed in both observation and CMIP6, accompanied by the eastward expansion of NAO north center. Spatial shift of the NAO forced the region of strong air‐sea interactions to shift and resulting in the collapse of NAO‐related SST_tri. These findings deepen our understanding of the NAO on the subseasonal scale. Plain Language Summary: A significant correlation between the North Atlantic Oscillation (NAO) and the North Atlantic tripole sea surface temperature (SST_tri) is widely recognized. However, this study found that the correlation between the two was significantly weakened in late winter during 1980–2001 while no such change was detected in early winter. Therefore, this paper will focus on the late winter and discuss the role of NAO spatial structure in the above correlation changes. When the NAO south center is located over the North Atlantic, both observations and the climate models indicate that the corresponding North Atlantic SST shows a significant tripole pattern. However, during 1980–2001, the NAO south center shift significantly eastward from the North Atlantic toward Western Europe (up to 20° longitude). At the same time, the NAO north center expanded eastward significantly. The eastward shift of the NAO results in the significant eastward shift of the turbulent heat flux and wind stress anomalies. Shift in the region of strong air‐sea interaction led to the collapse of NAO‐related SST_tri. These findings deepen our understanding of the NAO on the subseasonal scale and also provide implications for subseasonal‐seasonal predictions of Eurasian climate extremes. Key Points: The link between NAO and North Atlantic tripole SST weakened obviously during 1980–2001 late winter, which was not detected in early winterThe eastward shift of ∼20° longitude in NAO south center forced the strong air‐sea interactions region to shift in observations and CMIP6NAO's spatial shift in late winter caused the changes in the link between NAO and North Atlantic tripole SST [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion 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.)

Tornado outbreaks (TOs) are highly dangerous meteorological phenomena common in the United States and have limited known relationships with climate variability. Many of the challenges in understanding TOs result from a lack of formal TO quantification (both in definition and impact). Here, we present a TO definition based on a spatially cohesive and distinct region of tornado activity and present a TO intensity index using tornado characteristics within the TO region. In developing this index, we present a support vector regression-based detrending methodology to remove the secular trends within tornado reporting. The resulting TO definition suggests a decline in TO activity of roughly 1 TO per 4–5 years, with a similar decline in TO intensity. In addition, the relationship between this new quantification of TOs and common North American interannual and monthly climate variability indices is explored, namely the El Niño Southern Oscillation, the North Atlantic Oscillation, the Arctic Oscillation, and the Pacific North American Oscillation. In general, the links between these teleconnections and TO frequency and intensity were minimal (and sometimes in opposition when comparing TO frequency and intensity), but interesting patterns emerged that may offer an initial pathway to exploring longer-term TO predictability. [ABSTRACT FROM AUTHOR]

Background: Anticoagulant drugs are a valuable tool for minimizing thrombotic risks in at-risk patients. The purpose of this study is to conduct a literature review highlighting the management of these drugs during daily clinical dental practice. Materials and Methods: We limited our search to English-language papers published between 1 January 1989, and 7 March 2024, in PubMed, Scopus and Web of Science that were relevant to our topic. In the search approach, the Boolean keywords "anticoagulant AND dentistry" were used. Results: Twenty-five clinical trials were included for final review from 623 articles obtained from the databases Web of Science (83), PubMed (382), and Scopus (158), eliminating duplicates and 79 off-topic items, resulting in 419 articles after removing 315 entries and confirming eligibility. Overall, these studies support the use of local hemostatic measures to manage the risk of bleeding in patients on anticoagulant therapy undergoing dental procedures and highlight the importance of greater education and collaboration among healthcare professionals. Conclusions: Research and clinical investigation have improved understanding and management of dental procedures in patients undergoing anticoagulant or antiplatelet therapy. Hemostatic agents, clinical protocols, risk factors, and continuous education are essential for navigating the complexities of anticoagulant therapy, ensuring optimal outcomes and enhancing patient well-being. [ABSTRACT FROM AUTHOR]

The construction of sub‐daily pressure series is described for the cities of London (GB) and Paris (FR). The series extend back 1692 and 1748, respectively, and as such they represent two of the longest sub‐daily series of barometric pressure available. These series are updated from the previously documented London and Paris daily series and offer more homogeneous series, and in the case of the London series a more temporally complete sequence of data. A pairwise homogenization procedure has been applied to the two series alongside the long series of pressure that exists for De Bilt (NL). The De Bilt series has been available for some time in the International Surface Pressure Dataset (ISPD), but further quality control and homogeneity‐checking procedures have been applied to the data in this paper and therefore the three series are released together in this dataset. The series are of immediate interest for understanding changes to storm activity across the English Channel and North Atlantic region over an extended timeframe but may also be assimilated into reanalysis datasets such as the 20th‐century reanalysis. [ABSTRACT FROM AUTHOR]

Abstract This letter raises the possibility that ergodicity concerns might have some bearing on the signal‐to‐noise paradox. This is explored by applying the ergodic theorem to the theory behind ensemble weather forecasting and the ensemble mean. Using the ensemble mean as our best forecast of observations amounts to interpreting it as the most likely phase‐space trajectory, which relies on the ergodic theorem. This can fail for ensemble forecasting systems if members are not perfectly exchangeable with each other, the averaging window is too short and/or there are too few members. We argue these failures can occur in cases such as the winter North Atlantic Oscillation (NAO) forecasts due to intransitivity or regime behaviour for regions such as the North Atlantic and Arctic. This behaviour, where different ensemble members may become stuck in different relatively persistent flow states (intransitivity) or multi‐modality (regime behaviour), can in certain situations break the ergodic theorem. The problem of non‐ergodic systems and models in the case of weather forecasting is discussed, as are potential mitigation methods and metrics for ergodicity in ensemble systems.

The late Quaternary paleoclimate of the North Atlantic region has been widely studied, but the local terrestrial response to broader climatic variations remains underexplored. The Azores Archipelago, influenced by the North Atlantic Oscillation (NAO) and the Azores High, is a strategic target to investigate such interactions. Here, paleosols developed in equilibrium with the atmosphere recorded environmental variations in their geochemistry, and volcanic units sealing those paleosols allow for their precise dating. Clay mineralogical transfer functions from paleosol geochemistry and geochronological data were used to track paleoclimatic and paleoecological changes in this region over the past 1.3 Myr. Mean annual precipitation and air temperature reconstructions range from 620 to 1,520 mm yr−1 and 14–26°C, with the latter tightly coupled with previous reconstructions of sea surface temperature. New K‐Ar ages evidence pulsed soil formation periods under weathering‐favorable wet and warm conditions, suggesting periods of a persistent negative NAO with a weakened or more southern Azores High after glacial Terminations I, II, IV, V, IX, and X. Our humidity province reconstructions indicate a prevailing moist to wet forest under cool temperate to subtropical conditions, with less variability than continental Europe. A rapid paleoecological shift occurred at ∼430 ka in São Miguel Island, probably associated with the high amplitude of Termination V. Paleoecological changes younger than 430 ka could be related to local, not large‐scale, climate changes. Average past precipitations were ∼170 mm yr−1 lower than in the present, which suggests that modern weathering rates are higher than observed in our record. Plain Language Summary: In this work, we studied the local climate of the Azores volcanic islands in response to broader climatic changes over the past 1 million years. By studying the chemistry of paleosols–ancient soils incorporated into the geological record–we reconstructed the conditions of precipitation and temperature at the time of their formation. Air temperature reconstructions are similar to previous reconstructions of sea surface temperatures, suggesting a close relationship between atmospheric and sea surface temperatures in the North Atlantic region. The age determination of volcanic units allowed us to constrain the ages of paleosols. We observed that most paleosols developed quickly after the end of glacial periods, under wet and warm conditions that favored the fast transformation of volcanic products into soils. This indicates periods over which the Azores High–an atmospheric high‐pressure system that impacts the Azores' climate–was weakened or centered farther to the south of its current position. The chemistry of the paleosols registered fast environmental changes and suggests that the present annual precipitations are higher than over the past million years, which could impact the local economic activities and even the global climate, due to the capture of atmospheric CO2 through the weathering of volcanic rocks. Key Points: Precise K‐Ar geochronology revealed pulses of soil formation over the past 1 Myr in the Azores, Central North AtlanticPaleosols' geochemistry recorded paleoclimatic conditions and revealed fast environmental changesWet and warm climate resulted from persistent negative North Atlantic Oscillation conditions, favoring fast weathering of volcanic rocks [ABSTRACT FROM AUTHOR]

The response of the North Atlantic large‐scale circulation to El Niño–Southern Oscillation (ENSO) exhibits distinct differences between early (November–December) and late (January–February) winter. However, the reasons for this are unclear, particularly regarding the early winter response. Here we examine the role of storm‐track dynamics in influencing the intraseasonal variability of the ENSO teleconnection to the North Atlantic. During late winter there a broad weakening of the eddy heat flux upstream of the North Atlantic storm track during the El Niño phase, which is associated with a broad southward jet shift across North America and the North Atlantic. The late winter response is reinforced by synoptic eddies through enhanced cyclonic wave breaking, consistent with previous studies. However, a stronger teleconnection occurs during early winter. There are modest changes in the North Atlantic eddy heat flux, but strong changes in the upper‐level storm track associated with ENSO, with increased anticyclonic wave breaking during El Niño reinforcing the jet across the central North Atlantic. During early winter there are less frequent northern eddy‐driven jet occurrences in El Niño years and more frequent northern eddy‐driven jet occurrences in La Niña years. These poleward North Atlantic jet excursions typically follow peaks in the eddy heat flux; however, in El Niño years this relationship breaks down and the jet does not transition to the northern position as frequently, despite no clear changes in the upstream eddy heat flux. Composite analysis reveals that precursor storm‐track anomalies upstream over the eastern North Pacific/North America are important in suppressing the poleward jet excursions. These precursors map onto the seasonal mean North Pacific storm‐track anomalies during El Niño. Measured across all years, there is a clear relationship between the mean early winter eastern North Pacific storm‐track activity and eastern North Atlantic eddy‐driven jet, which can explain the early winter ENSO teleconnection to the North Atlantic. [ABSTRACT FROM AUTHOR]

This article explores the potential impact of climate change on loggerhead sea turtles in the Alboran Sea. The study focuses on sporadic nesting events in the western Mediterranean, which may indicate a colonization process. Genetic studies have shown past instances of colonization, and current climatic conditions in the western Mediterranean are suitable for nesting. The article also discusses the role of the North Atlantic Oscillation (NAO) in influencing sea turtle migration patterns. The findings have implications for loggerhead turtle conservation and highlight the expansion of nesting range within the Mediterranean basin. In Peru, a citizen science project has observed nesting behavior in two sea turtle species, despite nesting beaches not traditionally being found in the country. However, it is suggested that this may be due to inadequate beach surveys rather than a shift in sea turtle behavior. The absence of similar occurrences outside the Mediterranean suggests that additional factors beyond climate change may be involved. The NAO, which is sensitive to climate change, is expected to contribute to an increase in sporadic nesting on the beaches of the Alboran Sea in the future. [Extracted from the article]

Interaction between social robots and children occurs today in a variety of environments, including schools, hospitals, and homes. This review aims to highlight studies that delve into this interaction in the educational settings, exploring the characteristics of the social robot NAO and how its features influence its relationship with children. A search was conducted on July 1st, 2023 in Scopus and PsychInfo. Inclusion criteria pertained to (1) typical development; (2) age range 4-12 years; (3) educational setting; (4) type of robot (NAO); (5) type of publication: peer-reviewed journal; (6) language: English; (7) research studies. Of the 116 results that emerged from the search, 92 were excluded, yielding 24 valid results. We classified the records into two categories, namely 17 results were included in the "NAO as an informational and educational tool" category and 7 in the "NAO as a relational agent" category. The first category considers all studies where social robots were used as tools for educational and informational support; these studies delve into topics related to the teaching of school subjects and personalized learning, with a specific focus on emotional education. In the second category, we encounter studies that explore the relationships between children and robots, with a primary emphasis on the phenomenon of anthropomorphism, the attribution of mental states, touch interaction, and the robot's caregiving abilities. Based on the present review, social robots like NAO emerge as potential resources to implement new forms of teaching and interaction within the educational context; however, more research is needed to design developmentally-tailored programs and child-friendly features. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes (DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader (narrower) zonal scale dipolar structure possess a longer (shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM (1/1 DM) and a regional or sectoral DM (1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader (narrower) zonal scale possess a longer (shorter) persistence because the effects of the linear terms are less (more) pronounced when the atmospheric DMs have better (worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8 DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics. [ABSTRACT FROM AUTHOR]

Abstract The North Atlantic Oscillation (NAO) and North Atlantic tripole sea surface temperature (SST_tri) are important modes in the atmosphere and ocean over the North Atlantic, respectively. The link between the two is well‐known. However, this link weakened during 1980–2001, which is particularly pronounced in late winter and was not detected in early winter. This phenomenon has not been well revealed. The role of NAO in the above correlation changes was discussed. In late winter, a significant eastward shift (up to 20° longitude) of NAO south center during 1980–2001 was observed in both observation and CMIP6, accompanied by the eastward expansion of NAO north center. Spatial shift of the NAO forced the region of strong air‐sea interactions to shift and resulting in the collapse of NAO‐related SST_tri. These findings deepen our understanding of the NAO on the subseasonal scale.

Compound flooding was investigated in Halmstad on the Swedish west coast. The highest sea level ever recorded in Sweden was recorded by the Halmstad tide gauge. Moreover, through the city runs Nissan, one of the largest hydropower-producing rivers in southern Sweden. Together these features make the city an interesting location to study compound flooding. Co-variability between different hazards are studied using a unique set of downscaled climate scenario projections produced using state-of-the-art regional atmosphere, ocean and hydrological models. River discharge and sea level annual maxima are found to be correlated with peak strength on interannual time scales. This co-variability is found to derive from a mutual dependence that these hazards have on the North Atlantic Oscillation (NAO). Precipitation also shares this dependence in winter months and acts as a driver, building up the fluvial river hazard, while potentially adding additional pluvial hazard. Trends are also assessed, and it was found that future changes in compound flooding will most likely be driven primarily by mean sea level rise and secondarily by increases in mean river discharge.

Increasing the horizontal resolution of an ocean model is frequently seen as a way to reduce the model biases in the North Atlantic, but we are often limited by computational resources. Here, a two‐way nested ocean model configuration (VIKING10) that consists of a high‐resolution (1/10°) component and covers the northern North Atlantic, is embedded in a 1/2° ocean grid as part of the global chemistry‐climate model, FOCI (called FOCI‐VIKING10). This configuration yields a significantly improved path of the North Atlantic current (NAC), which here reduces the North Atlantic cold bias by ∼50%. Compared with the coarse‐resolution, non‐eddying model, the improved thermal state of upper ocean layers and surface heat fluxes in a historical simulation based on FOCI‐VIKING10 are beneficial for simulating the subdecadal North Atlantic Oscillation (NAO) variability (i.e., a period of 8 years). A northward drift of the NAO‐forced ocean thermal anomalies as seen in observations and the eddying FOCI‐VIKING10, provide a lagged ocean feedback to the NAO via changes in the net surface heat flux, leading to the NAO periodicity of 8 years. This lagged feedback and the 8 years variability of the NAO cannot be captured by the non‐eddying standard FOCI historical simulation. Furthermore, the argumentative responses of the North Atlantic to the 11‐year solar cycle are re‐examined in this study. The reported solar‐induced NAO‐like responses are confirmed in the 9‐member ensemble mean based on FOCI but with low robustness among individual members. A lagged NAO‐like response is only found in the nested eddying simulation but absent from the non‐eddying reference simulation, suggesting North Atlantic biases importantly limit climate model capability to realistically solar imprints in North Atlantic climate. Plain Language Summary: A long‐standing cold bias in the North Atlantic in climate models could be reduced by increasing the horizontal resolution, but we are often limited by computational resources. Here we embedded a nest with 1/10° resolution in the ocean in the North Atlantic in a global chemistry‐climate model (called FOCI‐VIKING10). It can largely reduce the North Atlantic cold bias (roughly 50%) and correct the path of the North Atlantic current (NAC). North Atlantic Oscillation (NAO) subdecadal variability (a period of 8 years) can be simulated by FOCI‐VIKING10 when the representations of the NAO‐forced anomalies and the ocean feedback are improved by alleviating the biases. The reported NAO‐like responses to the 11‐year solar cycle are confirmed in the 9‐member ensemble mean with FOCI (non‐eddying). Although the solar signals are also found in a single member with FOCI‐VIKING10, we cannot rule out the aliasing of the internal variability in this single short member. For detecting a weak or varying signal of external forcings like the 11‐year solar cycle in this study, a large ensemble with a "coarse" resolution model is favorable over a single realization with a "presumably" better model. Key Points: North Atlantic biases are alleviated by an eddying nested ocean configuration embedded in a global climate model, FOCI‐VIKING10It is indicated that reduction of the North Atlantic biases could improve the representation of NAO sub‐decadal (8 years) variabilityFor detecting weak external imprints with limited computational resources, an ensemble with a coarse‐resolution model is favorable [ABSTRACT FROM AUTHOR]

Research in the field of human–robot interactions (HRIs) has advanced significantly in recent years. Social humanoid robots have undergone severe testing and have been implemented in a variety of settings, for example, in educational institutions, healthcare facilities, and senior care centers. Humanoid robots have also been assessed across different population groups. However, research on various children groups is still scarce, especially among deaf children. This feasibility study explores the ability of both hearing and deaf children to interact with and recognize emotions expressed by NAO, the humanoid robot, without relying on sounds or speech. Initially, the children watched three video clips portraying emotions of happiness, sadness, and anger. Depending on the experimental condition, the children observed the humanoid robot respond to the emotions in the video clips in a congruent or incongruent manner before they were asked to recall which emotion the robot exhibited. The influence of empathy on the ability to recognize emotions was also investigated. The results revealed that there was no difference in the ability to recognize emotions between the two conditions (i.e., congruent and incongruent). Indeed, NAO responding with congruent emotions to video clips did not contribute to the children recognizing the emotion in NAO. Specifically, the ability to predict emotions in the video clips and gender (females) were identified as significant predictors to identify emotions in NAO. While no significant difference was identified between hearing and deaf children, this feasibility study aims to establish a foundation for future research on this important topic. [ABSTRACT FROM AUTHOR]

Humanoid robotics is an emerging field striving to deploy technological devices capable of resembling and mimicking the human form. Primarily, the capability of human-like robots to interact with people has proved to be contributory in areas such as education and caretaking, but less so in adult training. In this study, we outline the design and experiment of an escape room training activity facilitated by a humanoid robot (HR), NAO. An escape room is a gamified activity where a team of players must complete a series of challenges to "escape from the room" by opening four locks in a limited amount of time. Opening each lock required the team to find hints and solve problems mediated by NAO. During the activity, NAO provided ongoing feedback on the team's performance. Ten experts evaluated the experience and were asked about their overall assessment of the activity and the added value of NAO as a mediator. The results on the feasibility of NAO's serving as motivating tutor in adults' collaborative game-based learning were very encouraging. We believe this study marks the first step toward developing a generic template for learning and training processes supported by a HR. [ABSTRACT FROM AUTHOR]

North Atlantic blocking and the North Atlantic Oscillation (NAO) are two phenomena that have been extensively studied due to their significant spatio-temporal overlap. This work presents an index comparison study applied to this relationship, bringing light to how the strength of it varies considerably depending on blocking index choice and why this could be leading to discrepancies found in previous works. A PV–θ blocking index is used alongside a direction of breaking metric to classify blocking as either cyclonic or anticyclonic based on the Rossby wave breaking occurring at onset. These results are compared against those found using an absolute geopotential height (AGP) index. The analysis is performed using both area-averaged blocking count during winter and at each grid-point across the North Atlantic for all seasons. The study demonstrates that the choice of method significantly affects the results when correlating wintertime blocking and NAO. Blocks found using the AGP index show a much stronger correlation with the NAO compared to those found with the PV–θ index. Other analyses, such as frequency, duration, and composites, suggest that the AGP algorithm detects stronger, more mature, and persistent blocks, which promote a higher correlation with the NAO compared to the shorter-lived PV–θ blocks. Based on this analysis, it can be concluded that different blocking events are being measured between the two indices, contributing to the stark differences in the correlation analysis, each with their own advantages and disadvantages in relating blocking to the NAO. [ABSTRACT FROM AUTHOR]

The subject of the study was the effect of teleconnection patterns on cloudiness in Poland in the period 1990–2020. The analysis was conducted based on daily cloudiness values from 34 measurement stations of Institute of Meteorology and Water Management - National Research Institute and monthly North Atlantic Oscillation (NAO) and Scandinavia (SCAND) indices from the collection of Climate Prediction Center (CPC). The course of cloudiness values in winter in the multiannual period was analyzed together with its averaged spatial distrubution for the entire winter and for particular winter months. Next, the coefficient of correlation of cloudiness with a given teleconnection pattern index was calculated. The analysis also covered cloudiness in the positive and negative teleconnection phases. The results confirm a variable course and increasing trend of winter cloudiness in Poland. The average cloudiness reached 76% in the studied multiannual period. The correlation coefficient for the North Atlantic Oscillation primarily adopted negative values, and positive for the Scandinavian circulation. The strongest correlation between the teleconnection pattern and cloudiness was observed in February for NAO and in December for SCAND. Cloudiness showed no considerable differences between the positive and negative teleconnection phases. [ABSTRACT FROM AUTHOR]

Copyright of Atmosphere -- Ocean (Taylor & Francis Ltd) is the property of Taylor & Francis Ltd 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.)

Interaction between social robots and children occurs today in a variety of environments, including schools, hospitals, and homes. This review aims to highlight studies that delve into this interaction in the educational settings, exploring the characteristics of the social robot NAO and how its features influence its relationship with children. A search was conducted on July 1st, 2023 in Scopus and PsychInfo. Inclusion criteria pertained to (1) typical development; (2) age range 4-12 years; (3) educational setting; (4) type of robot (NAO); (5) type of publication: peer-reviewed journal; (6) language: English; (7) research studies. Of the 116 results that emerged from the search, 92 were excluded, yielding 24 valid results. We classified the records into two categories, namely 17 results were included in the “NAO as an informational and educational tool” category and 7 in the “NAO as a relational agent” category. The first category considers all studies where social robots were used as tools for educational and informational support; these studies delve into topics related to the teaching of school subjects and personalized learning, with a specific focus on emotional education. In the second category, we encounter studies that explore the relationships between children and robots, with a primary emphasis on the phenomenon of anthropomorphism, the attribution of mental states, touch interaction, and the robot's caregiving abilities. Based on the present review, social robots like NAO emerge as potential resources to implement new forms of teaching and interaction within the educational context; however, more research is needed to design...

This study investigates the long-term temporal patterns of sea level changes by analyzing monthly tide gauge data from 1950 to 2022 (42 to 72 years) along the European coastline and monthly altimetry data from 1992 to 2024 in the surrounding European seas. The primary focus is on signals with periods longer than 5 years. The application of wavelet-based approaches and multiresolution analysis has enabled the isolation of signals with periods of approximately 8 and 16 years. However, the latter has only been observed in tide gauge data, as the altimetry time series is not sufficiently long. The same analysis was applied to the North Atlantic Oscillation (NAO) and Atlantic Multidecadal Oscillation (AMO) indices, which enabled the detection of the same signals. The reported multiyear signals of sea level are correlated with NAO and AMO indices, particularly during the period spanning from 1975 to 2010.

Background: Anticoagulant drugs are a valuable tool for minimizing thrombotic risks in at-risk patients. The purpose of this study is to conduct a literature review highlighting the management of these drugs during daily clinical dental practice. Materials and Methods: We limited our search to English-language papers published between 1 January 1989, and 7 March 2024, in PubMed, Scopus and Web of Science that were relevant to our topic. In the search approach, the Boolean keywords “anticoagulant AND dentistry” were used. Results: Twenty-five clinical trials were included for final review from 623 articles obtained from the databases Web of Science (83), PubMed (382), and Scopus (158), eliminating duplicates and 79 off-topic items, resulting in 419 articles after removing 315 entries and confirming eligibility. Overall, these studies support the use of local hemostatic measures to manage the risk of bleeding in patients on anticoagulant therapy undergoing dental procedures and highlight the importance of greater education and collaboration among healthcare professionals. Conclusions: Research and clinical investigation have improved understanding and management of dental procedures in patients undergoing anticoagulant or antiplatelet therapy. Hemostatic agents, clinical protocols, risk factors, and continuous education are essential for navigating the complexities of anticoagulant therapy, ensuring optimal outcomes and enhancing patient well-being.

Tornado outbreaks (TOs) are highly dangerous meteorological phenomena common in the United States and have limited known relationships with climate variability. Many of the challenges in understanding TOs result from a lack of formal TO quantification (both in definition and impact). Here, we present a TO definition based on a spatially cohesive and distinct region of tornado activity and present a TO intensity index using tornado characteristics within the TO region. In developing this index, we present a support vector regression-based detrending methodology to remove the secular trends within tornado reporting. The resulting TO definition suggests a decline in TO activity of roughly 1 TO per 4–5 years, with a similar decline in TO intensity. In addition, the relationship between this new quantification of TOs and common North American interannual and monthly climate variability indices is explored, namely the El Niño Southern Oscillation, the North Atlantic Oscillation, the Arctic Oscillation, and the Pacific North American Oscillation. In general, the links between these teleconnections and TO frequency and intensity were minimal (and sometimes in opposition when comparing TO frequency and intensity), but interesting patterns emerged that may offer an initial pathway to exploring longer-term TO predictability.

AbstractThis study investigates the use of an assistive humanoid robot for teaching to and learning among young children in an informal learning environment. The robot is called NAO and built by SoftBank Robotics. NAO was used to teach a mathematic concept of measurement to young children. They engaged with the robot through the teaching and learning of presentation slides, worksheets, and playing cards. Their interactions with the robot formed the evidence of their learning. The children also played with the robot in an open and friendly environment, which was video recorded. The efficacy and impacts were measured and analyzed through social signals and verbal responses. Results show that the robot can build a positive and friendly relationship with children while achieving learning outcomes. This study demonstrates the possibilities of introducing NAO into the curriculum and calls for further research toward implementing humanoid robots in classroom settings.

Weather regimes are recurrent and quasi‐stationary large‐scale atmospheric circulation patterns, typically linking to surface weather. Two commonly used sets of weather regimes are wintertime North American and Euro‐Atlantic regimes. Notwithstanding recent evidence pointing to a connection between winter weather in North America and Europe, there is little knowledge on the possible relation between North American and Euro‐Atlantic regimes. Here, we find that specific pairs of North American and Euro‐Atlantic regimes show a close visual and statistical correspondence. Moreover, the joint analysis of the two sets of regimes can provide medium‐range statistical predictability for anomalies in their occurrence frequencies. Conditioning on North American weather regimes also results in anomalies in both the large‐scale circulation during specific Euro‐Atlantic regimes, and the associated European surface weather. We conclude that there is a benefit in conducting joint analyses of North American and European weather regimes, as opposed to considering the two in isolation. Plain Language Summary: Wintertime weather in Europe is closely related to large‐scale atmospheric patterns occurring over scales of thousands of kilometers. These patterns, termed weather regimes, are relatively persistent in time, and occur repeatedly. Such weather regimes have been used for many applications, including predicting the weather several weeks in advance. Weather regimes conceptually similar to those identified for Europe have also been determined for North America. In this study, we look at whether and how North American and European weather regimes are related. We show that the two sets of weather regimes have a statistical link, and that accounting for North American regimes can help to gain a more detailed understanding of how European regimes relate to weather in Europe. Key Points: Specific pairs of North American and Euro‐Atlantic weather regimes show a close relationA joint analysis of the two sets of regimes can provide statistical predictability for anomalies in their occurrence frequenciesNorth American regimes have a clear footprint on the European surface weather associated with Euro‐Atlantic regimes [ABSTRACT FROM AUTHOR]

In recent decades, the breeding populations of the yellow-legged gull Larus michahellis (YLG) have increased significantly, primarily due to the increase in open refuse dumps and discards from fisheries. Portugal's largest YLG breeding colony is located on Berlenga Island, where population numbers have been monitored since 1974. The population grew exponentially until 1994, prompting the implementation of population control measures, including culling adult birds and eggs. A long-term data base including number of breeding birds (since 1974), breeding parameters (since 2002), and trophic niches (using stable isotopes since 2011) of YLG breeding on Berlenga was related with oceanographic parameters, fish landings and quantity of urban waste. Trophic ecology showed strong relationships with oceanographic parameters (wNAO, Chl-a, and SST) and fisheries landings (the 10 most frequently consumed species by the YLG, traded at fish auctions in the main fishing harbour nearby). The results indicated significant relationships between reproductive performance and fisheries landings, particularly with demersal species that gulls primarily access through fisheries discards. However, population control measures played a pivotal role in stabilising and even reducing the population, despite sporadic events of poor oceanographic productivity in the past decade having a consistent impact on the reduction in breeding individuals. [ABSTRACT FROM AUTHOR]

The NAO teleconnective pattern has a great influence on the European climate; however, the exact quantification of NAO pattern in the different areas is sometimes lacking, and at other times, highlights even large differences between the various studies. This motivation led to the identification of the aim of this research in the study of the relationship between the NAO index and temperature and precipitation anomalies over the period 1991–2020, through the analysis of 87 rain gauges and 86 thermometric stations distributed as homogeneously as possible over the Italian territory. The results were sometimes at odds with the scientific literature on the subject, as significance was also found outside the winter season, e.g., in the spring for temperatures and in the autumn for precipitation, and in some cases, correlations were found, especially in August, even in southern Italy, which is usually considered a poorly correlated area. In addition, the linear relationship between the NAO index and temperature and precipitation anomalies was verified, with many weather stations obtaining significant coefficients of determinations as high as 0.5–0.6 in December, with 29 degrees of freedom, and a p-value set at 95%. Finally, for both climatic parameters, the presence of clusters and outliers at seasonal and monthly levels was assessed, obtaining a spatial distribution using the local Moran index, and summarising them in maps. This analysis highlighted important clusters in Northern and Central Italy, while clusters in the summer months occur in the South. These results provide information that may further elucidate local atmospheric dynamics in relation to NAO phases, as well as encourage future studies that may link other teleconnective indices aimed at better explaining the variance of climate parameters. [ABSTRACT FROM AUTHOR]

Many previous studies have documented the relationship between the North Pacific Oscillation (NPO) and the weather/climate of upstream and downstream regions. However, the stability of NPO precursor signals of East Asian summer precipitation, which is important for climate prediction, has received little attention. This study identified temporal variations in the connection between the May NPO and subsequent midsummer precipitation over Northeast China (NEC) during 1961–2020. During 1986–2010, the correlation between the May NPO and midsummer precipitation over NEC was found significantly positive, whereas the relation was found statistically insignificant during 1961–1985/2011–2020. Further results indicated that the NPO stimulated a Rossby wave source over the North Pacific that was stronger during 1986–2010 than during 1961–1985/2011–2020. The Rossby wave source anomalies shifted to North America and to the North Atlantic during the subsequent June and midsummer, respectively. Consequently, a teleconnection wave train, which originated over the North Pacific, propagated eastward to North America, across the North Atlantic, and on to East Asia on the subseasonal time scale, influencing midsummer precipitation over NEC through modulation of the atmospheric circulation (e.g., horizontal wind, moisture transport, and vertical movement). Moreover, the intensified Rossby wave anomalies associated with the May NPO were attributed to the strengthened NPO, which could be related to the enhanced standard deviation of SLP over the North Pacific. Additionally, the strengthened out‐of‐phase relation between the NPO and the North Atlantic Oscillation, resulting from changes in the background circulation, partially contributed to intensification of the Rossby wave train. Plain Language Summary: The North Pacific Oscillation (NPO) is an important intrinsic atmospheric variability which is characterized by a north–south seesaw in sea level pressure over the North Pacific Ocean. The NPO has substantial influences on the weather/climate conditions over North America and East Asia. However, the relation between NPO and East Asian climate is not stationary. This study identified a temporal variation in the connection between the May NPO and the midsummer precipitation over Northeast China (NEC) during 1961–2020, which shows a strong (weak) correlation during 1986–2010 (1961–1985 and 2011–2020). This is attributed to the different atmospheric circulation patterns caused by the NPO during the three periods. The NPO can simulate stronger perturbation to the atmosphere during 1986–2010 than during 1961–1985 and 2011–2020. Consequently, the perturbed atmospheric waves can propagate eastward to North America, across the North Atlantic, and toward East Asia during 1986–2010, leading to anomalous atmospheric circulation in East Asia and influencing the midsummer precipitation over NEC. The strengthening of the NPO and the enhanced relation between the NPO and North Atlantic Oscillation during 1986–2010 can explain the above changes. This study may deepen our understanding of the influence of NPO on the East Asian climate and may be meaningful for climate prediction. Key Points: The effect of May North Pacific Oscillation (NPO) on summer rainfall at Northeast China (NEC) is not stable, with a strong (weak) relation for 1986–2010 (for 1961–1985 and 2011–2020)This is attributed to a stronger Rossby wave source stimulated by NPO during 1986–2010 than during 1961–1985 and 2011–2020The strengthened Rossby wave related with NPO is attributed to the intensification of NPO and to the enhanced relation between NPO and North Atlantic Oscillation [ABSTRACT FROM AUTHOR]

• Preschoolers are being increasingly exposed to social robots. • Preschoolers can successfully participate in different tasks with a social robot. • Preschooler behavioural engagement was greater with a human instructor than a social robot. Young children are exposed to new digital technologies, such as social robots. Limited research exists on how children engage with social robots and their role in the preschool classroom. This study observed 35 English-speaking children (M age = 4.60 years) participating in two tasks (Simon Says and iPad drawing) under the guidance of a social robot or human instructor. Children's engagement was measured across behavioural, emotional, and verbal domains. Results showed higher behavioural and positive emotional engagement with a human instructor than a social robot instructor across both tasks. Children uttered more words with the human instructor than the social robot instructor for the iPad drawing task, although there were no differences for the Simon Says task. Children's engagement and utterances were positively correlated during the social robot and human instructor conditions. The findings suggest that child engagement was overall higher with a human than with a social robot and such differences may be important for teachers to consider when using social robots in the preschool classroom. [ABSTRACT FROM AUTHOR]

Given paleoclimatic evidence that the Atlantic Meridional Overturning Circulation (AMOC) may affect the global climate system, we conduct model experiments with EC-Earth3, a state-of-the-art GCM, to specifically investigate, for the first time, mechanisms of precipitation change over the Euro-Atlantic sector induced by a weakened AMOC. We artificially weaken the strength of the AMOC in the model through the release of a freshwater anomaly into the Northern Hemisphere high latitude ocean, thereby obtaining a ~ 57% weaker AMOC with respect to its preindustrial strength for 60 model years. Similar to prior studies, we find that Northern Hemisphere precipitation decreases in response to a weakened AMOC. However, we also find that the frequency of wet days increases in some regions. By computing the atmospheric moisture budget, we find that intensified but drier storms cause less precipitation over land. Nevertheless, changes in the jet stream tend to enhance precipitation over northwestern Europe. We further investigate the association of precipitation anomalies with large-scale atmospheric circulations by computing weather regimes through clustering of geopotential height daily anomalies. We find an increase in the frequency of the positive phase of the North Atlantic Oscillation (NAO+), which is associated with an increase in the occurrence of wet days over northern Europe and drier conditions over southern Europe. Since a ~ 57% reduction in the AMOC strength is within the inter-model range of projected AMOC declines by the end of the twenty-first century, our results have implications for understanding the role of AMOC in future hydrological changes. [ABSTRACT FROM AUTHOR]

The temporal variability of air temperature in the Middle Volga region from 1828 to 2021 is considered according to instrumental observations at the oldest meteorological station in the east of the East European Plain (Kazan University) and throughout the Asian part of Russia against the background of long-term climate fluctuations in the Northern Hemisphere of Earth. A general trend toward an increase in air temperature was revealed. It was found that climate change in Kazan was consistent with the climatic processes that occurred in the Middle Volga region as a whole. The greatest warming for the entire observation period was observed in the winter and spring seasons of the year. In December, warming occurred at a maximum rate of 0.28 °C/10 years. At the same time, the most intense warming process was observed from 1991 to 2021. The analysis of low-frequency fluctuations in the series of monthly average air temperatures made it possible to identify different periods of change, both in type (direction) and intensity. It is shown that in the Middle Volga region, positive anomalies of air temperature have occurred more often than negative ones in recent decades. Statistical data processing was also carried out for 30-year periods, starting from the first period, i.e., 1841–1870. This made it possible to reveal long-term changes in air temperature. Comparisons of climatic parameters in two periods, i.e., 1828–1945 and 1946–2021, allowed us to reliably detect the climatic beginning of the increasingly identifiable Anthropocene epoch (since 1946), characterized by a sharp increase in air temperature, increased interannual variability of the air temperature regime, and a significant increase (by about three times) in the rate of warming in the Middle Volga region. A correlation was made between atmospheric circulation indices and air temperature fluctuations in Kazan over different periods. The closest relationship was found for the 1990–2020 period. It is shown that the contribution of global factors to air temperature variability in the Middle Volga region during the Anthropocene reached 37% in winter and 32% in summer; in annual terms, this contribution amounted to 54%. [ABSTRACT FROM AUTHOR]

This retrospective study presents and summarizes our long-term efforts in the popularization of robotics, engineering, and artificial intelligence (STEM) using the NAO humanoid robot. By a conservative estimate, over a span of 8 years, we engaged at least a couple of thousand participants: approximately 70% were preschool children, 15% were elementary school students, and 15% were teenagers and adults. We describe several robot applications that were developed specifically for this task and assess their qualitative performance outside a controlled research setting, catering to various demographics, including those with special needs (ASD, ADHD). Five groups of applications are presented: (1) motor development activities and games, (2) children's games, (3) theatrical performances, (4) artificial intelligence applications, and (5) data harvesting applications. Different cases of human–robot interactions are considered and evaluated according to our experience, and we discuss their weak points and potential improvements. We examine the response of the audience when confronted with a humanoid robot featuring intelligent behavior, such as conversational intelligence and emotion recognition. We consider the importance of the robot's physical appearance, the emotional dynamics of human–robot engagement across age groups, the relevance of non-verbal cues, and analyze drawings crafted by preschool children both before and after their interaction with the NAO robot. [ABSTRACT FROM AUTHOR]

The influence of the climate signal variability on warm spell characteristics is examined using observed daily temperature data from meteorological stations during the cold season (November to March) from 1961 to 2019 over Iran. Warm spells are classified by characteristics such as frequency, number, duration and intensity. Analysis shows the statistically significant positive correlation between Indian Ocean Dipole (IOD), Atlantic Multidecadal Oscillation (AMO) and Atlantic Meridional Mode (AMM) and negative correlation between North Atlantic Oscillation (NAO) and warm spell characteristics. However, partial correlation analysis used to extract respective influence of climate signals showed a significant negative correlation only with NAO. This study found that NAO influences on the number and frequency of warm spells in western part of Iran. The higher temperature during negative phase of NAO linked to the enhanced cyclonic circulation and associated with westerly to southwesterly airflows which provides warm air advection over Iran during weaker than normal subtropical high. In a positive NAO, anomalously negative geopotential height is centred over the Iceland and anomalously positive geopotential height is located across subtropical Atlantic Ocean and Europe. Elongated area of subtropical high can influence Arabian Peninsula and Iran. In this regard, the cold temperature over the western part of Iran during positive phase of NAO is linked to the enhanced northerly and northwesterly cold air stream over Eastern Europe which influence north of Middle East as well as Iran. [ABSTRACT FROM AUTHOR]

The common snipe (Gallinago gallinago) is a wader that breeds in subarctic regions from Iceland to Russia, and for which global populations are in decline. We studied snipe breeding in western Iceland between 1998 and 2020, locating nests and ringing birds annually. In 2019 and 2020, we deployed geolocators on nesting adults to estimate the timing of their annual migration and the location of overwintering areas. Birds moved principally between breeding locations in Iceland to wintering areas in Ireland, although some birds may winter farther north. We also found that apparent annual adult survival averaged 66%, but was higher in years with warmer, wetter winters. Given the similarity of our survival estimates to those from snipe elsewhere, we suggest that adult survival is unlikely a major contributor to declining populations, and other factors like habitat loss may be of more concern.

The area of Agadir, which is situated on Morocco's southern Atlantic coast, is characterized by an arid climate, and has been strongly impacted by climate change. The purpose of this research is to assess observed and modeled drought variability in time, on the basis of rainfall time series for the periods 1973–2020, and 2022 – 2099 by use of SPI, short for Standardized Precipitation Index. Findings from the SPI analysis show that the years from 1981 to 1986 were the driest as per the instrumental record. Future SPI projections indicate that the area under study will face several prolonged drought and wet periods between 2022 and 2099. The longest drought will take place from 2090 to 2093. Analysis of the relationship between rainfall in Agadir and North Atlantic Oscillation (NAO), is also studied especially for the winter months. The results of the study will provide a basis for drought surveillance and hydro-meteorological studies, in addition to initiating the desired managment of environment in this area.

Abstract Weather regimes are recurrent and quasi‐stationary large‐scale atmospheric circulation patterns, typically linking to surface weather. Two commonly used sets of weather regimes are wintertime North American and Euro‐Atlantic regimes. Notwithstanding recent evidence pointing to a connection between winter weather in North America and Europe, there is little knowledge on the possible relation between North American and Euro‐Atlantic regimes. Here, we find that specific pairs of North American and Euro‐Atlantic regimes show a close visual and statistical correspondence. Moreover, the joint analysis of the two sets of regimes can provide medium‐range statistical predictability for anomalies in their occurrence frequencies. Conditioning on North American weather regimes also results in anomalies in both the large‐scale circulation during specific Euro‐Atlantic regimes, and the associated European surface weather. We conclude that there is a benefit in conducting joint analyses of North American and European weather regimes, as opposed to considering the two in isolation.

Abstract Many previous studies have documented the relationship between the North Pacific Oscillation (NPO) and the weather/climate of upstream and downstream regions. However, the stability of NPO precursor signals of East Asian summer precipitation, which is important for climate prediction, has received little attention. This study identified temporal variations in the connection between the May NPO and subsequent midsummer precipitation over Northeast China (NEC) during 1961–2020. During 1986–2010, the correlation between the May NPO and midsummer precipitation over NEC was found significantly positive, whereas the relation was found statistically insignificant during 1961–1985/2011–2020. Further results indicated that the NPO stimulated a Rossby wave source over the North Pacific that was stronger during 1986–2010 than during 1961–1985/2011–2020. The Rossby wave source anomalies shifted to North America and to the North Atlantic during the subsequent June and midsummer, respectively. Consequently, a teleconnection wave train, which originated over the North Pacific, propagated eastward to North America, across the North Atlantic, and on to East Asia on the subseasonal time scale, influencing midsummer precipitation over NEC through modulation of the atmospheric circulation (e.g., horizontal wind, moisture transport, and vertical movement). Moreover, the intensified Rossby wave anomalies associated with the May NPO were attributed to the strengthened NPO, which could be related to the enhanced standard deviation of SLP over the North Pacific. Additionally, the strengthened out‐of‐phase relation between the NPO and the North Atlantic Oscillation, resulting from changes in the background circulation, partially contributed to intensification of the Rossby wave train.

Variability in the North Atlantic Oscillation (NAO) has contributed to the recent multidecadal trends observed in European climate, especially to trends in winter precipitation over Northern Europe. However, the current generation of coupled climate models struggle to reproduce the NAO's contribution to multidecadal trends, which has important implications for deriving constraints based on the comparison of observed and modeled trends. An observational constraint based on attribution results, both with and without the contribution of variability associated with the NAO, is applied to projections of Northern European precipitation and temperature, and observed NAO variability is shown to lead to a constraint that overestimates future forced changes. Only after removing the NAO variability is the observed climate change consistent with model simulations, and a tighter, unbiased observational constraint based on the forced signal (without the NAO) can be applied to future projections. Plain Language Summary: The observed precipitation and temperature across Northern Europe in winter has been increasing over the past several decades. However, the magnitude of this trend is generally not well reproduced by the latest set of global climate models. A part of the observed increase in precipitation can be related to the variability in the North Atlantic Oscillation (NAO), which is a large‐scale pattern of sea level pressure in the North Atlantic region that varies in strength each season and year, and is strongly linked to temperature and precipitation patterns across Europe, particularly in winter. In this study, we show that if the variability related to the NAO is first removed from the precipitation time series, from both the observations and the model simulations, the difference between the long‐term observed and modeled trends in precipitation is reduced. Removing the NAO variability also has an impact on the difference in observed and modeled trends in temperature. This has important implications for approaches that use the difference in observations and model simulations as a way of constraining future projections of climate change. Key Points: Variability in the North Atlantic Oscillation (NAO) has contributed to the recent multidecadal trends observed in European climateThe suite of current comprehensive global models (CMIP6) struggle to reproduce the NAO's contribution to multidecadal trendsRemoving the NAO from both observations and models provides a tighter, unbiased constraint, which can then be applied to model projections [ABSTRACT FROM AUTHOR]

Teleconnection patterns are one of the key features to understanding high‐frequency natural climate variability. The North Sea‐Caspian Pattern (NCP) was identified as a middle tropospheric dipole and its hydroclimatological implications have been substantially restricted to the Eastern Mediterranean region. Thus, the hydroclimatological influences of the NCP in the Euro‐Mediterranean region were investigated via a comparative approach with dominant tropospheric teleconnections in the Eurasian region and synoptic features such as ridge‐trough positioning and strength. By using high‐resolution ERA5 reanalysis data, cross‐correlations between indexes, anticorrelations at 500 hPa and composite anomaly maps for seasonally representative months were produced to understand the working mechanism of the NCP. Comparisons included the East Atlantic/Western Russian (EAWR) pattern, a rotated principal component analysis (RPCA) variant of NCP which utilizes pole‐based representation. Analysis revealed that the NCP was correlated well with the Mediterranean trough displacement and with the strength of the East Asian trough. Climate anomalies indicated by the NCP were greater and more spatially consistent compared to other teleconnections. The NCP also showed higher contrasts of temperature and precipitation than the EAWR based on the composite anomaly maps. In conclusion, the NCP explained climate variability in all seasons linking remote centres of action within Eurasia's east and west extremes. [ABSTRACT FROM AUTHOR]

Autoregressive spectral analysis revealed underlying cyclical trends in the highly variable biomass and mean body weight indices of two Northwest Atlantic squid species with opposing life histories. Doryteuthis pealeii attaches its egg masses to the seabed in shallow waters on the Northeast USA shelf. The broader-ranging Illex illecebrosus uses the Gulf Stream (GS) to transport its pelagic egg masses and paralarvae from the Southern (USA shelf) to the Middle (Scotian Shelf) and Northern (Grand Banks) Fishery Regions. We compared significant spectral peaks, or cycles, between the 1993–2016 survey indices, GS latitudinal positions (at 74°, 70°, 65°, 60°, 55° and 50°W) and winter North Atlantic Oscillation (NAO) indices to reveal any synchronicities. Positive NAO anomalies associated with northward GS position shifts were predominant. NAO indices exhibited 2–3-year, 4–5-year, and near-decadal cycles. GS position periodicities included 2–3-year, 3–4-year, and both timescales for west of 65°W (Western Segment), east of 60°W (Eastern), and from 65° to 60°W, respectively. I. illecebrosus indices exhibited stock-wide 3–4-year cycles and 2–3-year cycles for the Middle and Southern Fishery Regions that were synchronous with GS latitudinal positions for the Eastern and Western GS Segments, respectively. D. pealeii biomass cycles varied seasonally. Spring 4–5-year cycles were synchronous with the NAO, and fall near-decadal cycles were synchronous with the NAO and all GS locations analyzed. Our findings of inter-annual biomass and body weight cycles from 2 to 3 years to near-decadal are remarkable given the sub-annual lifespans of both species, but confirm the tight coupling between recruitment, body size, and cyclical environmental forcing factors. [ABSTRACT FROM AUTHOR]

Morocco is characterized by a semi-arid climate influenced by the Mediterranean, Atlantic, and Saharan environments, resulting in high variability in rainfall and hydrological conditions. Certain regions suffer from insufficient understanding concerning the spatiotemporal patterns of precipitation, along with facing recurrent periods of drought. This study aims to characterize the current trends and periodicities of precipitation in west-central Morocco at monthly and annual scales, using data from six rain gauges. The link between monthly precipitation and both the North Atlantic Oscillation (NAO) and the Western Mediterranean Oscillation (WeMO) indices was tested to identify potential teleconnections with large-scale variability modes. The results reveal interannual variability in precipitation and climate indices, while showing decreasing insignificant trends in annual precipitation. On a monthly scale, temporal precipitation patterns are similar to the annual scale. Furthermore, a remarkably robust and significant component with a periodicity of 6–8 years emerges consistently across all monitoring stations. Intriguingly, this band exhibits a more pronounced presence on the plains as opposed to the mountainous stations. Additionally, it is noteworthy that the NAO modulated winter precipitation, whereas the influence of the WeMO extends until March and April. This mode could be linked to the fluctuations of the WeMO from 1985 to 2005 and, subsequently, to NAO variations. Indeed, this is consistent with the strong significant correlations observed between rainfall and the NAO/WeMO. This study serves as a baseline for future research aiming to understand the influence of climate indices on rainfall in the North African region. [ABSTRACT FROM AUTHOR]