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Mediterranean-type climates are defined by temperate, wet winters, and hot or warm dry summers and exist at the western edges of five continents in locations determined by the geography of winter storm tracks and summer subtropical anticyclones. The climatology, variability, and long-term changes in winter precipitation in Mediterranean-type climates, and the mechanisms for model-projected near-term future change, are analyzed. Despite commonalities in terms of location in the context of planetary-scale dynamics, the causes of variability are distinct across the regions. Internal atmospheric variability is the dominant source of winter precipitation variability in all Mediterranean-type climate regions, but only in the Mediterranean is this clearly related to annular mode variability. Ocean forcing of variability is a notable influence only for California and Chile. As a consequence, potential predictability of winter precipitation variability in the regions is low. In all regions, the trend in winter precipitation since 1901 is similar to that which arises as a response to changes in external forcing in the models participating in phase 5 of the Coupled Model Intercomparison Project. All Mediterranean-type climate regions, except in North America, have dried and the models project further drying over coming decades. In the Northern Hemisphere, dynamical processes are responsible: development of a winter ridge over the Mediterranean that suppresses precipitation and of a trough west of the North American west coast that shifts the Pacific storm track equatorward. In the Southern Hemisphere, mixed dynamic–thermodynamic changes are important that place a minimum in vertically integrated water vapor change at the coast and enhance zonal dry advection into Mediterranean-type climate regions inland.

A lack of reliable winter hardiness has impeded the adoption of winter barley (Hordeum vulgare L.) in much of the northern United States. Direct selection for winter survival is time consuming and often unreliable. In addition, because survival is a binary trait, selection towards small quantitative gains can be difficult. One solution to these challenges is to identify indirect selection traits: anatomical or physiological characteristics which can be measured in the absence of winter stress, but which contribute to improved winter survival. Here, we survey a range of winter and spring barley, as well as winter wheat, winter rye, and perennial species of the genus Hordeum, all of which are more winter hardy than barley, to identify traits associated with winter survival. We identified several traits as promising candidates for selection. These included crown depth and leaf metaxylem diameter, which previous studies have identified as indirect selection traits. New candidates identified by our study include crown diameter and leaf midvein and blade thickness, as well as a suite of traits which suggest a pattern of reduced and efficient investment in above-ground structures. The effect of these traits on winter survival need to be validated and quantified by further experiments, but they represent a promising early step in a potentially valuable breeding strategy.

Higher precipitation is expected over most of the world’s continents under climate change, except for a few specific regions where models project robust declines. Among these, the Mediterranean stands out as a result of the magnitude and significance of its winter precipitation decline. Locally, up to 40% of winter precipitation could be lost, setting strong limits on water resources that will constrain the ability of the region to develop and grow food, affecting millions of already water-stressed people and threatening the stability of this tense and complex area. To this day, however, a theory explaining the special nature of this region as a climate change hot spot is still lacking. Regional circulation changes, dominated by the development of a strong anomalous ridge, are thought to drive the winter precipitation decline, but their origins and potential contributions to regional hydroclimate change remain elusive. Here, we show how wintertime Mediterranean circulation trends can be seen as the combined response to two independent forcings: robust changes in large-scale, upper-tropospheric flow and the reduction in the regional land–sea temperature gradient that is characteristic of this region. In addition, we discuss how the circulation change can account for the magnitude and spatial structure of the drying. Our findings pave the way for better understanding and improved modeling of the future Mediterranean hydroclimate.

Sentinel-2 imagery is an unprecedented data source with high spatial, spectral and temporal resolution in addition to free access. The objective of this paper was to evaluate the potential of using Sentinel-2 data to map winter crops in the early growth stage. Analysis of three winter crop types—winter garlic, winter canola and winter wheat—was carried out in two agricultural regions of China. We analysed the spectral characteristics and vegetation index profiles of these crops in the early growth stage and other land cover types based on Sentinel-2 images. A decision tree classification model was built to distinguish the crops based on these data. The results demonstrate that winter garlic and winter wheat can be distinguished four months before harvest, while winter canola can be distinguished two months before harvest. The overall classification accuracy was 96.62% with a kappa coefficient of 0.95. Therefore, Sentinel-2 images can be used to accurately identify these winter crops in the early growth stage, making them an important data source in the field of agricultural remote sensing.

Crop supply and management is a global issue, particularly in the context of global climate change and rising urbanization. Accurate mapping and monitoring of specific crop types are crucial for crop studies. In this study, we proposed: (1) a methodology to map two main winter crops (winter wheat and winter barley) in the northern region of Finistère with high-resolution Sentinel-2 data. Different classification approaches (the hierarchical classification and the classical direct extraction), and classification methods (pixel-based classification (PBC) and object-based classification (OBC)) were performed and evaluated. Subsequently, (2) a further study that involved monitoring the phenology of the winter crops was carried out, based on the previous results. The aim is to understand the temporal behavior from sowing to harvesting, identifying three important phenological statuses (germination, heading, and ripening, including harvesting). Due to the high frequency of precipitation in our study area, crop phenology monitoring was performed using Sentinel-1 C-band SAR backscatter time series data using the Google Earth Engine (GEE) platform. The results of the classification showed that the hierarchical classification achieved a better accuracy when it is compared to the direct extraction, with an overall accuracy of 0.932 and a kappa coefficient of 0.888. Moreover, in the hierarchical classification process, OBC reached a better accuracy in cropland mapping, and PBC was proven more suitable for winter crop extraction. Additionally, in the time series backscatter coefficient of winter wheat, the germination and ripening (harvesting) phases can be identified at VV and VH/VV polarizations, and heading can be identified in both VV and VH polarizations. Secondly, we were able to detect the germination phase of winter barley in VV and VH, ripening with both polarizations and VH/VV, and finally, heading in VV and VH polarizations.

During recent years, the rapidly warming Arctic and its impact on winter weather and climate variability in the mid- and low latitudes have been the focus of many research efforts. In contrast, anomalous cool Arctic summers and their impacts on the large-scale circulation have received little attention. In this study, we use atmospheric reanalysis data to reveal a dominant pattern of summer 1000–500-hPa thickness variability north of 30°N and its association with East Asian heat waves. It is found that the second thickness pattern exhibits strong interannual variability but does not exhibit any trend. Spatially, the positive phase of the second thickness pattern corresponds with significant Arctic cold anomalies in the mid- and low troposphere, which are surrounded by warm anomalies outside the Arctic. This pattern is the thermodynamic expression of the leading pattern of upper-tropospheric westerly variability and significantly correlated with the frequency of EastAsian heat waves. TheArctic has experienced frequent summer cold anomalies since 2005, accompanied by strengthened tropospheric westerly winds over most of the Arctic and weakened westerlies over the mid- and low latitudes of Asia. The former significantly enhances baroclinicity over the Arctic, which dynamically contributes to increased frequency of anomalous low surface pressure during summer along with decreased frequency over high latitudes of Eurasia and North America. The latter is exhibited by sustained high pressure anomalies in the mid- and low troposphere that dynamically facilitate the occurrence of East Asian heat waves. A systematic northward shift of Asian zonal winds dynamically links Arctic cold anomalies with East Asian heat waves and produces a seesaw structure in zonal wind anomalies over the Arctic and the Tibetan Plateau (the third pole). Evidence suggests that enhanced Arctic westerlies may provide a precursor to improve predictions of the East Asian winter monsoon, though the mechanism for this lag association is unclear.

The boreal winter precipitation variability over East Asia and the western North Pacific is often attributed to the El Niño-Southern Oscillation (ENSO). The present study investigates the independent impacts of the East Asian winter monsoon (EAWM) on winter precipitation anomalies over East Asia and the western North Pacific. It is revealed that anomalous EAWM is accompanied by a south-north dipole pattern of precipitation anomalies in the above regions. During strong EAWM years, the enhanced northeasterly winds induce anomalous convergence and divergence over the tropical and subtropical regions, respectively, leading to anomalous ascent and above-normal precipitation over the southern South China Sea-Philippine Sea and anomalous descent and below-normal precipitation over eastern China-subtropical western North Pacific. Opposite convergence, vertical motion and precipitation anomalies are induced in the above regions during weak EAWM years. In the observations, both ENSO and EAWM contribute to the south-north dipole precipitation anomaly pattern with a larger contribution from ENSO and EAWM for the tropical and subtropical precipitation anomalies, respectively. Atmospheric model experiments with climatological annually varying sea surface temperature forcing confirm the independent role of the EAWM in the formation of the south-north dipole precipitation anomaly pattern. A moisture budget diagnosis shows that the dynamic effect associated with vertical motion is dominant in the formation of the above precipitation anomaly pattern in both the observations and model simulations. The horizontal moisture transport has an additional contribution to the formation of subtropical precipitation anomalies.

Siempre ha habido mujeres artistas, igual que siempre ha habido madres, sin embargo, desde las Venus prehistóricas, la maternidad no ha sido nunca un asunto central del arte. Algunas de ellas son Louise Bourgeois, Frida Kahlo, Rineke Dijstra, Sally Mann, Elena del Rivero, Eulalia Valldosera, o Ana Álvarez Errecalde, por citar a algunas de ellas, entre muchas otras.

Introduction Maladaptive cognitions associated with lower light availability in winter and the changing of the seasons are elevated in winter depression and are treatment targets in psychotherapy. Mechanisms underlying the development of SAD-specific cognitions may be related to seasonal variation in melanopsin-driven retinal responsivity to light. Prior work has shown reduced retinal responsivity to light during the winter in seasonal depression. We hypothesized maladaptive seasonal cognitions would be associated with reduced retinal responses to light. We also tested whether age moderated this relationship, hypothesizing that this learned association may only appear in older individuals who have experienced a greater number of seasonal depressive episodes. Methods Participants ages 19-65 (M=36.13, SD=12.81) with seasonal depression (n=37) and non-depressed controls (n=32) completed assessments in winter months (21st December to 21st March). Maladaptive seasonal cognitions were measured by the Seasonal Beliefs Questionnaire (SBQ). Melanopsin-driven retinal responsivity was assessed using the post illumination pupil response (PIPR). Net PIPR as a percent of baseline was averaged across the 10-30 seconds post-stimulus for use in analyses. Using multiple regression, we tested (1) if seasonal beliefs predict the PIPR and (2) if an interaction between seasonal beliefs and age predicts the PIPR, controlling for gender, the pupillary light reflex (PLR), and circadian time of testing from Dim Light Melatonin Onset. Results Seasonal beliefs were not associated with the PIPR (b= -0.86e-5, SE=0.27e-3, p=0.98). There was a significant interaction between seasonal beliefs and age on the PIPR (b= -0.56e-4, SE=0.23e-4, p=0.02), in which greater seasonal beliefs were associated with reduced PIPR in older individuals but not younger individuals. The Johnson-Neyman interval indicated that in participants above age 49, greater seasonal beliefs were significantly associated with lower retinal responsivity (PIPR; p< 0.05). Conclusion Greater seasonal beliefs were associated with reduced retinal responsivity, but only in older adults with seasonal depression. It is possible that reduced retinal responsivity creates learned maladaptive schemas regarding seasonal changes that are reinforced with annually recurring winter depressive episodes. However, longitudinal data focused on changes in seasonal beliefs resulting from reduced retinal sensitivity is necessary to test whether retinal responsivity is a mechanism in the formation of these seasonal-specific cognitions. Support (if any)

A warming climate is expected to have an impact on the magnitude and timing of river floods; however, no consistent large-scale climate change signal in observed flood magnitudes has been identified so far. We analyzed the timing of river floods in Europe over the past five decades, using a pan-European database from 4262 observational hydrometric stations, and found clear patterns of change in flood timing. Warmer temperatures have led to earlier spring snowmelt floods throughout northeastern Europe; delayed winter storms associated with polar warming have led to later winter floods around the North Sea and some sectors of the Mediterranean coast; and earlier soil moisture maxima have led to earlier winter floods in western Europe. Our results highlight the existence of a clear climate signal in flood observations at the continental scale.