Extreme Winter Temperatures Research Articles

Survival analysis of freezing stress in the North American native perennial flax, Linum lewisii Pursh

Abstract The expansive range of Lewis flax (Linum lewisii Pursh.), an herbaceous perennial, exposes the species to a diversity of climatic conditions. As interest in the domestication and adoption of perennial crop alternatives grows and interest in this species for natural area restoration continues, the assurance of a commercial plant variety’s ability to endure the full range of possible climatic extremes is paramount. This study examines the freezing tolerance of a geographically representative sampling of 44 Lewis flax accessions at winter temperature extremes experienced in the northern Great Plains of the United States. Survival analysis models were adapted to include temperature exposure, in replacement of ordinal time typically used in such models, to produce statistics evaluating reactions to extreme temperatures that Lewis flax would encounter in our field environments. Our results revealed Lewis flax is more freezing tolerant than previously reported, and revealed four accessions with significantly superior genetic freezing tolerance than the released ‘Maple Grove’ cultivar. Furthermore, regrowth analyses indicate variation among accessions not associated with survival, which could lead to improving regrowth rate and survival simultaneously. These findings and their methodology expand the understanding of Lewis flax adaptation for winter hardiness and offer an efficient, new model that can be used to evaluate freezing tolerance at ordinal temperatures without requiring extensive prior physiological knowledge for a species.

Evaluation of Pre-Analytical Variables for Human Papillomavirus Primary Screening from Self-Collected Vaginal Swabs

HPV primary screening is an effective approach to assessing cervical cancer risk. Self-collected vaginal swabs have shown promise to expand testing access, but there are limited data defining analytical performance criteria necessary for adoption of self-collected specimens, especially for those occurring outside the clinic where the swab remains dry during transport. Here, we evaluated the performance of self-collected vaginal swabs for HPV detection using the Roche Cobas 6800. There was insignificant variability between swabs self-collected by the same individual (n=15 participants collecting 5 swabs/participant), measured by amplification of HPV and human β-globin control DNA. Comparison of self-collected vaginal swab and provider-collected cervical samples (n=144 paired collections) proved highly concordant for HPV detection (total agreement=90.3%;PPA=84.2%). There was no relationship between the number of dry storage days and amplification of HPV (n=68, range 4-41days). Exposure of self-collected dry swabs to extreme summer and winter temperatures did not affect testing outcomes. We assessed a second internal control (RNAseP) in a subset and demonstrate that lack of amplification for β-globin from self-collected specimens was consistent with poor, but not absent, cellularity. These data suggest that self-collected vaginal samples enable accurate clinical HPV testing, and that extended ambient dry storage or exposure to extreme temperatures do not influence HPV detection. Further, lack of β-globin amplification in HPV negative samples accurately identified participants that required recollection.

Jet Configurations Leading to Extreme Winter Temperatures Over Europe

AbstractThe North Atlantic eddy‐driven jet (EDJ) is the main driver of winter weather in Europe and has often been described by its latitude or strength. Here, we show that the influence of the EDJ on European winter temperature extremes can be better characterized by a multiparametric perspective that accounts for additional aspects of the EDJ structure (tilt, zonal elongation, etc.). We identify four regions where extreme temperatures are distinctly associated with the EDJ: Scandinavia, Central Europe, Eastern Europe, and Western Mediterranean (WMED). Overall, the anomalous horizontal advection induced by blockings during cold spells and enhanced westerlies during warm events is the main mechanism leading to extreme event occurrence. However, diabatic processes play an important role in WMED region. Both processes generate asymmetric effects in minimum and maximum temperatures contributing to higher intensities of cold than warm events. These extreme events are associated with different EDJ configurations, which typically involve perturbed EDJs during cold spells and strong tilted EDJs during warm events, but with important variations depending on the region. In almost every region, the combined effects of more than two EDJ parameters yield significant increases in the probability of cold and warm events, suggesting an oversimplification of traditional approaches based on a single EDJ parameter. We show, using logistic regression models, that, although important, latitude and intensity are often unable to discriminate unequivocally the region of extreme event occurrence, and in some regions, they do not drive the largest changes in the odds of extremes.

Variation of temperature extremes in wintertime over Beijing-Tianjin-Hebei region in the era of sharp decline of Arctic sea ice

The more frequent winter temperature extremes have exerted significant negative impacts on the coordinated development of the Beijing-Tianjin-Hebei(BTH) region of China during the recent decades. To more deeply understand the extreme temperature events(ETEs) in the region, in this study, the temperature intra-seasonal variability(TSV) and ETEs are investigated based on the observation data. Our results suggest that the TSV of wintertime over the BTH region has significantly amplified in the era of sharp decline of Arctic sea ice during 1990/1991–2020/2021, which is reflected by a polarization between warm and cold extremes, particularly increasing cold nights and temperature whiplash events. The amplified TSV is mainly driven by the abnormal atmospheric circulation triggered by rapidly melting autumn Arctic sea ice. The synergistic effects of obviously weakened polar vortex, significantly strengthened Ural Blocking High (UH) and Siberian High (SH), and increased days of extreme negative phase of Arctic Oscillation (AO), which are conducive to the inverted Ω type circulation at 500 hPa, may cause more cold extremes and enhance the TSV in the BTH region since 1990/1991 winter. While global warming favors more frequent warm extremes in this region. We hope this study can help reduce the impact of ETEs and provide some scientific support for the coordinated development of the BTH region.

PiCAM: A Raspberry Pi‐based open‐source, low‐power camera system for monitoring plant phenology in Arctic environments

Abstract Time‐lapse cameras have been widely used as a tool to monitor the timing of seasonal vegetation growth. These simple, relatively inexpensive systems can provide high‐frequency observations of leaf development and demography which are critical data sets needed to characterize plant phenology from species to landscapes. This is important for understanding how plants are responding to global changes, as well as for validating satellite‐derived phenology products. However, in remote regions including the high‐latitude Arctic, deploying time‐lapse cameras could be challenging. The remoteness and lack of widespread power and telecommunications infrastructure limit options for the installation, maintenance and retrieval of data and equipment, and make it difficult for cameras to survive in extreme weather (e.g. long cold winters). To improve our understanding of Arctic phenology, new technologies are required to address these challenges. Here, we present a novel, low‐power, compact, lightweight time‐lapse camera system, called power‐interval camera automation module (PiCAM). The PiCAM was designed with explicit consideration to simplify deployment (i.e. without a need for external power supplies) of camera systems and to address the challenges of camera survival in harsh Arctic environments. In this paper, we describe the design, setup and technical details of the PiCAM and provide a roadmap for how to build and operate these systems. As proof of concept, we deployed 26 PiCAMs at three low‐Arctic tundra sites on the Seward Peninsula, Alaska in early August 2021 for characterizing Arctic plant phenology. Of the 26 PiCAMs, 70% remained active at the point of our revisit in late July 2022 despite the extreme winter temperatures they experienced (< −30°C, heavy snow cover). We extracted key plant phenology metrics from the PiCAMs and captured strong differences across key Arctic plant species. We showed that the PiCAM has the potential to be widely used for monitoring plant phenology across the broader Arctic region, addressing the need for ground‐based understanding of Arctic phenological diversity to develop knowledge of plant response to climate change and to validate remote sensing products.

Carrying out the demercurization of heavy metals (mercury) using the Denite immobilizer and its effect on the soil

On the territory of the Northern industrial zone of Pavlodar in the area of the industrial wastewater reservoir «Bylkyldak» in some areas of the earth there is soil contamination with mercury, exceeding the MPC for mercury (2.1 mg/kg) by 500 times. The total mass of mercury dispersed in the surface layer of soils is 2.8 tons. The mass of contaminated soil is approximately 208,000 tons. Pollution of the territory is historical. The purpose of the article is to determine the efficiency of chemical binding (immobilization) of mercury in the soil with the Japanese drug Denite® in real field conditions of the territory of mercury contamination in the Northern industrial zone of Pavlodar using an experimental study; to determine the stability of insoluble mercury compounds formed by the preparation at extreme winter and summer temperatures and seasonal fluctuations in open ground. Soil samples were taken for the study at 11 points in the centers of mercury pollution. Laboratory studies were carried out in an accredited analytical laboratory of the Testing Center of JSC Caustic. Soil samples were treated with Denite®, the preparations obtained were stabilized, and water extracts were prepared. The content of mercury in soils, extracts from them, and plants was determined by the atomic absorption method on a RA-915+ spectrometer equipped with RP-91 and RP-91S attachments. As a result of research, the effectiveness of Denite® in the chemical binding of mercury in the soil has been proven and its optimal dosages have been determined. As a result of the positive tests of the technology of chemical immobilization of mercury, the prospect of a practical solution to the issue of demercurization of mercury-contaminated soil on the territory of the Northern industrial zone appeared.

Increasing the Biodiversity of the Dendroflora of Sparsely Wooded Regions by Adapted Representatives of the Genus Robinia L.

Purpose of the study: to substantiate the prospects of using various species, varieties and forms of the genus Robinia in protective afforestation and landscaping of settlements in dry-steppe and semi-desert zones of southern Russia. It is established that the main limiting factors affecting the growth, development and condition of representatives of the genus Robinia in the Volgograd region are winter temperatures up to −37 °C, as well as poor moisture availability and uneven distribution of precipitation during the growing season in combination with extremely low temperatures in the autumn–winter period. All representatives of the generic complex belong to the group of plants that start late and finish the vegetative period late. Phenological atypicity is in the lower half of the normal range, with indicators from +1 °C to 0, which indicates a high level of adaptation to the climatic conditions of the region. In the process of long-term acclimatization, many introduced species have developed a number of genotypic adaptations and are currently able to tolerate extreme winter temperatures up to −37 °C. An assessment of potential drought resistance based on the water-retaining ability of the leaves showed that higher rates of water-resistance capacity (76.8% water loss) are typical of R. neomexicana, which has a natural distribution area in the western arid part of the North American continent. R. viscosa var. hartwegii, with a natural distribution in the areas of the monsoon subtropical climate of eastern North America, is distinguished by low indicators (94.1% water loss), as are clonal decorative forms of R. pseudoacacia: f. pyramidalis and f. umbraculifera (97.6–95.8% water loss), which are common only in culture and characterized by a whole complex of low indicators of bioecological stability. The data obtained by us allow us to recommend the following assortment of species and forms of Robinia for protective afforestation and landscaping in the arid territories of southern Russia: R. pseudoacacia, R. neomexicana var. neomexicana, R. neomexicana var. rusbyi and R. pseudoacacia x R. neomexicana.

Changes in Winter Temperature Extremes From Future Arctic Sea‐Ice Loss and Ocean Warming

AbstractObserved rapid Arctic warming and sea‐ice loss are likely to continue in the future, unless and after greenhouse gas emissions are reduced to net‐zero. Here, we examine the possible effects of future sea‐ice loss at 2°C global warming above pre‐industrial levels on winter temperature extremes across the Northern Hemisphere, using coordinated experiments from the Polar Amplification Model Intercomparison Project. 1‐in‐20‐year cold extremes are simulated to become less severe at high‐ and mid‐latitudes in response to Arctic sea‐ice loss. 1‐in‐20‐year winter warm extremes become warmer at northern high latitudes due to sea‐ice loss, but warm by less than cold extremes. We compare the response to sea‐ice loss to that from global sea surface temperature (SST) change also at 2°C global warming. SST change causes less severe cold extremes and more severe warm extremes globally. Except northern high latitudes, the response to SST change is of larger magnitude than that to Arctic sea‐ice loss.

Evaluation of an open forecasting challenge to assess skill of West Nile virus neuroinvasive disease prediction

BackgroundWest Nile virus (WNV) is the leading cause of mosquito-borne illness in the continental USA. WNV occurrence has high spatiotemporal variation, and current approaches to targeted control of the virus are limited, making forecasting a public health priority. However, little research has been done to compare strengths and weaknesses of WNV disease forecasting approaches on the national scale. We used forecasts submitted to the 2020 WNV Forecasting Challenge, an open challenge organized by the Centers for Disease Control and Prevention, to assess the status of WNV neuroinvasive disease (WNND) prediction and identify avenues for improvement.MethodsWe performed a multi-model comparative assessment of probabilistic forecasts submitted by 15 teams for annual WNND cases in US counties for 2020 and assessed forecast accuracy, calibration, and discriminatory power. In the evaluation, we included forecasts produced by comparison models of varying complexity as benchmarks of forecast performance. We also used regression analysis to identify modeling approaches and contextual factors that were associated with forecast skill.ResultsSimple models based on historical WNND cases generally scored better than more complex models and combined higher discriminatory power with better calibration of uncertainty. Forecast skill improved across updated forecast submissions submitted during the 2020 season. Among models using additional data, inclusion of climate or human demographic data was associated with higher skill, while inclusion of mosquito or land use data was associated with lower skill. We also identified population size, extreme minimum winter temperature, and interannual variation in WNND cases as county-level characteristics associated with variation in forecast skill.ConclusionsHistorical WNND cases were strong predictors of future cases with minimal increase in skill achieved by models that included other factors. Although opportunities might exist to specifically improve predictions for areas with large populations and low or high winter temperatures, areas with high case-count variability are intrinsically more difficult to predict. Also, the prediction of outbreaks, which are outliers relative to typical case numbers, remains difficult. Further improvements to prediction could be obtained with improved calibration of forecast uncertainty and access to real-time data streams (e.g. current weather and preliminary human cases).Graphical

Frequency of the winter temperature extremes over Siberia dominated by the Atlantic Meridional Overturning Circulation

Widespread observed and projected increases in warm extremes, along with decreases in cold extremes, have been confirmed as being consistent with global and regional warming. Here we disclosed that the decadal variation in the frequency of the surface air temperature (SAT) extremes over Siberia in winter was primarily dominated by the Atlantic Meridional Overturning Circulation (AMOC) rather than anthropogenic forcing. The stronger AMOC induced more warm and cold extremes through increasing the variance of winter SAT over Siberia while the direct effect of external forcings, especially anthropogenic greenhouse gases, had little impact on the summation of warm and cold extremes due to equivalent effects on the increases in warm extremes and decreases in cold extremes. The possible mechanism can be deduced that the stronger AMOC stimulated the propagation of the wave train originated in the North Atlantic Ocean, across mid- to high latitudes, thereby increasing the variabilities in the circulations over the Ural blocking region and Siberia, which are critical to the SAT extremes there.

Dynamics of Two Distinct Subseasonal Growth Mechanisms of the North Pacific Oscillation

Abstract This study investigates the growth mechanisms of the North Pacific Oscillation (NPO), one of the primary causes of winter temperature extremes at midlatitudes. We find that the NPO has two distinct origins. One is the Rossby wave propagating across Eurasia that strengthens during cold or warm surges over East Asia. The corresponding vorticity and thermal anomalies grow into the NPO as they move eastward. The other is a local disturbance at the Asian Pacific jet stream exit that amplifies when propagating westward. The dynamical processes behind these two types of NPO growth are investigated by conducting quasigeostrophic geopotential tendency budget analysis, focusing on the relative importance of the vorticity flux and differential heat flux. It is revealed that the contribution of high-frequency eddies is greater in the NPO that grows from a local disturbance. However, NPO growth in both cases is primarily steered by low-frequency vorticity flux, which facilitates eastward or westward propagation through relative or planetary vorticity advections, respectively. Differential heat flux promotes the growth of the NPO before the onset, but dissipates the NPO anomalies afterward. The net effect of the heat flux, however, allows the NPO to amplify and persist through baroclinic instability by constraining the NPO anomalies to have westward vertical tilt. Accordingly, the NPO grows conforming to the dissipative destabilizing mechanism. From the perspective of potential vorticity (PV), the eastward growth of the NPO originates from the downstream advection of PV anomalies accumulated over East Asia, while westward growth is favored by a strong PV gradient near the jet stream. Significance Statement This study examines the origins and growth mechanism of the North Pacific Oscillation (NPO), which causes cold or warm spells in the midlatitudes during winter. Two distinct origins of the NPO are found, which are abnormal temperature events over East Asia and local atmospheric disturbances at the Asian Pacific jet stream exit. Evolutions of the NPO are traced by analyzing the roles of the vorticity and heat fluxes in addition to the contributions of synoptic eddies, which turns out to be more significant for the NPO that grows from a local disturbance. Vorticity flux overall dominates the growth of the NPO, but heat flux also helps the NPO amplify owing to background instability.

On the seasonal prediction and predictability of winter surface Temperature Swing Index over North America

The rapid day-to-day temperature swings associated with extratropical storm tracks can cause cascading infrastructure failure and impact human outdoor activities, thus research on seasonal prediction and predictability of extreme temperature swings is of huge societal importance. To measure the extreme surface air temperature (SAT) variations associated with the winter extratropical storm tracks, a Temperature Swing Index (TSI) is formulated as the standard deviation of 24-h-difference-filtered data of the 6-hourly SAT. The dominant term governing the TSI variability is shown to be proportional to the product of eddy heat flux and mean temperature gradient. The seasonal prediction skill of the winter TSI over North America was assessed using Geophysical Fluid Dynamics Laboratory's new seasonal prediction system. The locations with skillful TSI prediction show a geographic pattern that is distinct from the pattern of skillful seasonal mean SAT prediction. The prediction of TSI provides additional predictable climate information beyond the traditional seasonal mean temperature prediction. The source of the seasonal TSI prediction can be attributed to year-to-year variations of the El Niño-Southern Oscillation (ENSO), North Pacific Oscillation (NPO), and Pacific/North American (PNA) teleconnection. Over the central United States, the correlation skill of TSI prediction reaches 0.75 with strong links to observed ENSO, NPO, and PNA, while the skill of seasonal SAT prediction is relatively low with a correlation of 0.36. As a first attempt of diagnosing the combined predictability of the first-order (the seasonal mean) and second-order (TSI) statistics for SAT, this study highlights the importance of the eddy-mean flow interaction perspective for understanding the seasonal climate predictability in the extra tropics. These results point toward providing skillful prediction of higher-order statistical information related to winter temperature extremes, thus enriching the seasonal forecast products for the research community and decision makers.

Restoring a keystone tree species for the future: American chestnut assisted migration plantings in an adaptive silviculture experiment

Species ranges are forecast to change in response to warming temperatures and altered precipitation patterns, yet tree migration rates fail to track the pace of climate change. In anticipation of these changes, various forest adaptation management strategies have been broadly proposed, including intentionally modifying species composition via assisted migration of future climate adapted species. Despite the potential utility of these adaptation measures, practical evaluations are limited, particularly those applied to meet other ecological objectives such as supporting vulnerable, underrepresented, or degraded populations of foundational species. In this study, we examined the 4-year seedling survival and morpho-physiological response of American chestnut (Castanea dentata (Marsh.) Borkh.; n = 959 seeds sown), a functionally extirpated species. American chestnuts were grown within sixteen replicated 0.1 and 0.4 ha harvest gaps as part of a 160 ha co-developed (manager-scientist designed), operational-scale silvicultural trial (conditions of sufficient scope to be representative of commercial forest operations) in a northern-hardwood forest in the northeastern US. Chestnut restoration and migration potential (e.g., survival, absolute and relative growth rates, photosynthetic capacity) was assessed against the biophysical controls exerted on seedlings (e.g., understory competition, injury associated with browse and extreme cold winter temperatures) and in comparison to seedlings planted from eight other tree species (n = 480 planted per species) identified for assisted migration. Our results show the performance of American chestnut seedlings is controlled by the strength of local competition (odds of survival increased 2.6 times between four understory competition classes, p < 0.001) and cumulative winter shoot injury (relative growth in aboveground biomass adjusted for injury R2 = -0.85, p < 0.001) associated with cold intolerance likely linked to northward movement of chestnut seedlings transferred outside of their parental range. Still, the combined survival-growth response for American chestnuts ranked among the highest (2nd out of 6 possible rankings) relative to the other species tested, and even outperformed other comparable assisted migration species introduced from outside of their parental range. The implications of these findings highlight the potential for American chestnut plantings to be incorporated within both restoration and broader climate adaptation frameworks. Despite these promising outcomes, important biophysical (e.g., vegetative competition, harvest treatment, and variability in insulative snowpack) and climatic barriers for the reestablishment of this species remain. Given the paucity of reproductively viable American chestnuts or disease resistant breeding programs along northern range limits, this may generate a reliance on plant material obtained from outside of historically recognized safe transfer distances; however, increasingly shifting climate and species ranges may lead to better climate matches in the long term. Nevertheless, the broader applicability of this work illustrates the potential for cultural and ecological keystone species restoration efforts to be incorporated within climate adaptation frameworks to assist in the establishment of compositionally diverse and future climate-adapted forests.

Winter severity affects occupancy of spring‐ and summer‐breeding anurans across the eastern United States

AbstractAimClimate change is an increasingly important driver of biodiversity loss. The ectothermic nature of amphibians may make them particularly sensitive to changes in temperature and precipitation regimes, adding to declines from other threats. While active season environmental conditions can influence growth and survival, effects of variation in winter conditions on population dynamics are less well‐studied. Given that extreme winter temperatures can influence amphibian survival and fitness, we expected that increased winter severity—as measured by variability in winter temperatures and snow cover—would be associated with decreased occupancy, and that populations that experience more severe winters would have the largest sensitivities and show the greatest declines.LocationEastern United States.Time period2001–2015.Major taxa studiedAnurans.MethodsWe used large‐scale citizen science data from the eastern half of the United States, a diverse biogeographic and climatic region, to assess how variation in winter severity influenced occupancy dynamics (i.e. presence or absence of species across sites and years) of 11 spring and summer breeding anuran species.ResultsMost species had increased occupancy in years with greater than average snow cover and warmer than average mean winter temperatures. Surprisingly, climatic conditions in winter affected occupancy dynamics of species with varying life history characteristics, including both spring and summer breeding species, those that overwinter under the soil, and those that overwinter in ponds and stream beds. For two wide‐ranging species (Lithobates catesbeianus and Lithobates clamitans), colder winter temperatures reduced occupancy more at northern latitudes, while the association between days of snow cover and latitude was equivocal.Main conclusionsAs the climate continues to change, expected reductions in snowpack may reduce occupancy of already declining anuran populations, while milder winters may improve overwinter survival for some species. The contradictory impacts of temperature and snow cover illustrate the importance of considering multi‐dimensional impacts of climate change on anuran populations.

Gongolaria barbata forest in the shallow lagoon on the southern Istrian Coast (northern Adriatic Sea)

Abstract The Gongolaria barbata forest inhabiting Šćuza lagoon on the southern Istrian coast (northern Adriatic) represents the last significant refuge for this species among the shallow waters of the Istrian Coast. The lagoon is characterised by extreme winter and summer temperatures. Moreover, the absence of certain grazers could be one of the main factors favouring the development and growth of G. barbata forest. Two morphologically distinct forms of G. barbata inhabit the lagoon: attached and detached. Abundance and morphological characteristics of each form were analysed in randomly sampled thalli. The wet weight, thallus length, number of cauloids and total cauloid length were significantly higher in the detached than in the attached form. Although the main cauloid was highly branched in both forms, its total length was up to three times higher in the detached than in the attached form. Our study suggests that this population of G. barbata can thrive in the extreme conditions found in the lagoon, while also exhibiting two distinct forms. Furthermore, this large population could serve as a donor for future restoration attempts on the western Istrian Coast where a decline of G. barbata has been confirmed in recent years.

Variation of Rodents’ Body Temperature across Elevation in Alps

AbstractUnderstanding the physiological adaptations of animals living in mountain landscapes is a key to predicting the responses of individuals to environmental changes, especially those imposed by climate. In this regard, the mechanism of body temperature regulation is particularly important in determining the physiological limits for activity under hypoxic and climatic stressful conditions. Numerous studies have shown that body temperature of rodents and other animals decreases with elevation and with extreme winter temperatures. But surprisingly, it is still not known how body temperature of wild animals varies along elevation during their reproductive seasons. We studied variation in core body temperature among individuals () of four rodent species (Apodemus flavicollis, Apodemus sylvaticus, Apodemus alpicola, Myodes glareolus) and its association with elevation (from 400 to 1,822 m asl), accounting for variation in environment temperature, microhabitat structure, body condition, and sex. Results showed a strong positive effect of elevation and a more limited effect of environmental temperature on rodents' body temperature during spring and summer. The effect of elevation on body temperature was influenced neither by interactions with environmental temperature or sex nor by the microhabitat structure. We suggest that in normothermic condition at high elevations, small mammals experiencing hypoxic exposure might show physiological adjustments for increasing efficiency of thermoregulation in low oxygen conditions.

Predictive Skill of Teleconnection Patterns in Twentieth Century Seasonal Hindcasts and Their Relationship to Extreme Winter Temperatures in Europe

European winter weather is dominated by several low-frequency teleconnection patterns, the main ones being the North Atlantic Oscillation, East Atlantic, East Atlantic/Western Russia and Scandinavian patterns. We analyze the century-long ERA-20C reanalysis and ASF-20C seasonal hindcast datasets and find that these patterns are subject to decadal variability and fluctuations in predictive skill. Using indices for determining periods of extreme cold or warm temperatures, we establish that the teleconnection patterns are, for some regions, significantly correlated or anti-correlated to cold or heat waves. The seasonal hindcasts are however only partly able to capture these relationships. There do not seem to be significant changes to the observed links between large-scale circulation patterns and extreme temperatures between periods of higher and lower predictive skill.

Influence of Rootstock on Yield Quantity and Quality, Contents of Biologically Active Compounds and Antioxidant Activity in Regent Grapevine Fruit.

The cultivation of vines in temperate climates poses many difficulties to be overcome. The soil and climatic conditions in Poland limit the choice of vine varieties that can be used in the field; therefore, growers are often limited to varieties that are tolerant to extreme winter temperatures and spring frosts and to cultivars that are able to achieve optimum berry maturity at the end of the season. The study evaluated the effect of six rootstock types and own-root bushes on yield quantity and quality and on the content of biologically active compounds and antioxidant activity in Regent grapevine fruit. The research was conducted in 2015 at NOBILIS Vineyard (50°39′ N; 21°34′ E) in the Sandomierz Upland. Among the evaluated rootstocks, 125AA turned out to exert the significantly best effect on the yield, grape and berry weight, and number of grapes per bush. The fruit from bushes grafted on the 5BB rootstock were characterised by the highest content of L-ascorbic acid and tannins.

Cyber-attacks and their implications for emergency management.

Emergency management has rightfully given attention to a variety of emergencies and disasters that have occurred throughout the United States over the past few years and months. Foremost among them is COVID-19, which underscores the need for improvements in public health preparedness and response. But the country has also been impacted by major hurricanes/tropical storms, damaging Derecho windstorms, devastating urban-wildland fires, significant floods, notable social unrest/riots, extreme winter temperatures and accompanying loss of electricity, and many other costly and deadly events including a disturbing building collapse in Surfside, Florida. This list is not comprehensive, of course. It excludes other concerns regarding rising social vulnerability, shortsighted development decisions, a degraded environment, and our inadequate and decaying infrastructure. It is understandable, therefore, that we are focused on the pressing issues of the day and needed changes in our policy priorities. Unfortunately, this may cause us to possibly overlook other potential risks.

Evaluating Postharvest Organic Nitrogen Fertilizer Applications in Early Fruiting Northern Highbush Blueberry

Bloom to fruit maturity is a period of rapid growth and nitrogen (N) uptake in northern highbush blueberry (Vaccinium corymbosum L.). Sufficient plant-available N is critical during this time, and growers often accomplish this through fertilizer applications from bloom through fruit development. For organic production in northern climates like Washington State, postharvest applications of N fertilizer are not recommended for northern highbush blueberry because they may stimulate excessive vegetative growth, reduce floral bud set, and increase the risk of winter injury through delayed acclimation. However, early fruiting cultivars with the potential for an extended growing season after harvest may benefit from postharvest N applications because the additional N may promote shoot and root growth that could support fruit production in future years while still allowing plants to form floral buds and acclimate to winter temperatures. The objective of this study was to evaluate the potential impacts of postharvest organic N fertilizer applications on ‘Duke’, an early fruiting northern highbush blueberry cultivar. Specific objectives were to determine the effects of postharvest organic N fertilizer application on plant growth, yield, floral bud set, fruit quality, cold hardiness, tissue macronutrient concentrations, and select soil properties. Four treatments varying in the timing of N application were evaluated in a commercial ‘Duke’ field in eastern Washington using a single fertilizer rate of 130 kg⋅ha−1 N from 2018 to 2020. The organic fertilizer N source was a liquid fertilizer derived from digested plant materials. The experimental design was a randomized complete block design with four replications and treatments included the following: control (100% of N applied preharvest); 80/20 (80% preharvest, 20% postharvest); 70/30 (70% preharvest, 30% postharvest); and 60/40 (60% preharvest, 40% postharvest). Although the year influenced measured variables, including yield, floral bud set, fruit quality, tissue nutrients, and soil properties, few treatment effects were observed across the 3-year study. Cold hardiness was only impacted once (8 Feb. 2020), and floral buds were overall hardy to extreme minimum winter temperatures for the region. This project showed that applying postharvest organic N as a liquid fertilizer had no negative consequences on productivity metrics for an early fruiting blueberry cultivar grown in a region with an extended growing season, thus providing growers with more flexibility when timing their fertilizer applications. Results may differ for other fertilizer sources, and further monitoring of soil NO3-N accumulation should be conducted to gain a better understanding of its dynamics and the potential for risks.