Warm Years Research Articles

Climate Change and Urban Climate in the Western Balkans

Global climate change is a process that inevitably affects the European continent, and thus the countries of the Western Balkans, i.e. Bosnia and Herzegovina, which is located in Southeast Europe. Increasingly intense and long-lasting heat waves (especially during the summer period), the occurrence of intense cold waves in winter, intense short-term precipitation periods, as well as long-term dry periods are the consequences of climate change characteristic of the Western Balkans, and thus Bosnia and Herzegovina. Such temperature and precipitation extremes have become more frequent in the last twenty‒thirty years, as evidenced by the annual air temperatures in all Western Balkan countries, i.e. it is clear that most of the last few years are the warmest years since the beginning of the 20th century. Due to such extreme weather events, it is clear that urban areas in the Western Balkans are under stronger, primarily thermal pressure, due to the already modified micro and local climate due to the characteristics of surface geometry. As a result, even higher temperatures and a significantly higher number of tropical nights occur during the heat waves, and have a direct threat to the health of the population and the economy in urban areas. This study analyzed 49 publications that directly or indirectly analyze, primarily thermal values and indices, in urban areas in the Western Balkans, in Banja Luka, Novi Sad, Belgrade, Tirana and Skopje. The results clearly show higher thermal pressure in urban areas, when it comes to temperatures and indices of thermal comfort, and maximum differences in relation to the natural environment occur in the most urbanized and industrial parts of the city. Also, analyzes of thermal risk on the quality and mortality of the population in urban areas show that increased mortality is in the category of residents over 65 years of age.

Seasonal evolution of the supraglacial drainage network at Humboldt Glacier, northern Greenland, between 2016 and 2020

Abstract. Supraglacial rivers and lakes are important for the routing and storage of surface meltwater during the summer melt season across the Greenland Ice Sheet (GrIS) but remain poorly mapped and quantified across the northern part of the ice sheet, which is rapidly losing mass. Here we produce, for the first time, a high-resolution record of the supraglacial drainage network (including both rivers and lakes) and its seasonal behaviour at Humboldt Glacier, a wide-outlet glacier draining a large melt-prone hydrologic catchment (13 488 km2), spanning the period 2016 to 2020 using 10 m spatial resolution Sentinel-2 imagery. Our results reveal a perennially extensive yet interannually variable supraglacial network extending from an elevation of 200 m a.s.l. to a maximum of ∼ 1440 m a.s.l. recorded in 2020, with limited development of the network observed in the low-melt years of 2017 and 2018. The supraglacial drainage network is shown to cover an area ranging between 966 km2 (2018) and 1566 km2 (2019) at its maximum seasonal extent, with spatial coverage of up to 2685 km2 recorded during the early phases of the melt season when a slush zone is most prominent. Up-glacier expansion and the development of an efficient supraglacial drainage network as surface runoff increases and the snowline retreats is clearly visible. Preconditioning of the ice surface following a high-melt year is also observed, with an extreme and long-lasting 2019 melt season and over-winter persistence of liquid lakes, followed by low snow accumulation the following spring, culminating in earlier widespread exposure of the supraglacial drainage network in 2020 compared to other years. This preconditioning is predicted to become more common with persistent warmer years into the future. Overall, this study provides evidence of a persistent, yet dynamic, supraglacial drainage network at this prominent northern GrIS outlet glacier and advances our understanding of such hydrologic processes, particularly under ongoing climatic warming and enhanced runoff.

Europe's energy security: From Russian dependence to renewable reliance

This paper examines the impact of EU energy policies, namely the National Energy and Climate Plans (NECP19) and REPowerEU (2022), on the European natural gas security of supply. Our analysis shows that the REPowerEU plan significantly cuts gas demand by 133 bcm compared to NECP19. This shift can make Europe independent from Russian gas by 2030. Executing REPowerEU requires faster, clean technology deployment. The EU needs to catch up in installations to reach REPowerEU targets, while NECP19 maintains high gas demand (423 bcm till 2030), potentially exacerbating gas import dependence. NECP19 not only raises gas demand but also brings substantial inter-annual variation (IAV) of demand. In cold years (twice in ten years), demand spikes by 39 bcm, and warm years (three in ten years) decrease it by 23 bcm. REPowerEU, while moderately increasing gas demand variation (around 7% versus NECP19), does not solve the demand variability issue. In extremely cold years (one in forty years), Europe may face a 46 bcm gap, around a quarter of the spot LNG market. Failing REPowerEU not only heightens gas import risk but also risks price spikes under varying climates and global market conditions. We offer policy recommendations to address potential price spikes related to IAV demand.

Climate warming could free cold-adapted trees from C-conservative allocation strategy of storage over growth.

Carbon allocation has been fundamental for long-lived trees to survive cold stress at their upper elevation range limit. Although carbon allocation between non-structural carbohydrate (NSC) storage and structural growth is well-documented, it still remains unclear how ongoing climate warming influences these processes, particularly whether these two processes will shift in parallel or respond divergently to warming. Using a combination of an insitu downward-transplant warming experiment and an ex situ chamber warming treatment, we investigated how subalpine fir trees at their upper elevation limit coordinated carbon allocation priority among different sinks (e.g., NSC storage and structural growth) at whole-tree level in response to elevated temperature. We found that transplanted individuals from the upper elevation limit to lower elevations generally induced an increase in specific leaf area, but there was no detected evidence of warming effect on leaf-level saturated photosynthetic rates. Additionally, our results challenged the expectation that climate warming will accelerate structural carbon accumulation while maintaining NSC constant. Instead, individuals favored allocating available carbon to NSC storage over structural growth after 1 year of warming, despite the amplification in total biomass encouraged by both insitu and ex situ experimental warming. Unexpectedly, continued warming drove a regime shift in carbon allocation priority, which was manifested in the increase of NSC storage in synchrony to structural growth enhancement. These findings imply that climate warming would release trees at their cold edge from C-conservative allocation strategy of storage over structural growth. Thus, understanding the strategical regulation of the carbon allocation priority and the distinctive function of carbon sink components is of great implication for predicting tree fate in the future climate warming.

Spring temperature predicts upstream migration timing of invasive Sacramento pikeminnow within its introduced range

Rapid climate change and invasive species introductions threaten ecological communities across the globe. Freshwaters are particularly vulnerable and impacted, especially when these stresses coincide. We document the migration of an invasive piscine predator, the Sacramento pikeminnow (Ptychocheilus grandis), within its introduced range, the South Fork Eel River, California, USA. Snorkel surveys and temperature monitoring in 2015–2019 showed that pikeminnow migrate upstream during spring and early summer, with earlier migration in warmer years. We developed a statistical temperature model to forecast the timing and extent of upstream migration by pikeminnow under varying combinations of discharge and air temperature. Modeled river temperature increased with air temperature and downstream and decreased with discharge. In years with low discharge and high air temperature, we predict pikeminnow will move upstream earlier, increasing spatial and temporal overlap in their summer range with native fishes. Managing conditions that reduce pikeminnow co-occurrence with native fishes (i.e., decreasing river temperature) could increase amount and duration of predator-free habitat for native fishes. We predict invasive pikeminnow will have larger impacts on invaded riverine communities with global warming and increasing drought severity. Knowledge of life history and phenology, for pikeminnow and other organisms, can guide effective management as conditions change and help to limit adverse impacts of introduced organisms on native species.

Fishery catch records support machine learning-based prediction of illegal fishing off US West Coast.

Illegal, unreported, and unregulated (IUU) fishing is a major problem worldwide, often made more challenging by a lack of at-sea and shoreside monitoring of commercial fishery catches. Off the US West Coast, as in many places, a primary concern for enforcement and management is whether vessels are illegally fishing in locations where they are not permitted to fish. We explored the use of supervised machine learning analysis in a partially observed fishery to identify potentially illicit behaviors when vessels did not have observers on board. We built classification models (random forest and gradient boosting ensemble tree estimators) using labeled data from nearly 10,000 fishing trips for which we had landing records (i.e., catch data) and observer data. We identified a set of variables related to catch (e.g., catch weights and species) and delivery port that could predict, with 97% accuracy, whether vessels fished in state versus federal waters. Notably, our model performances were robust to inter-annual variability in the fishery environments during recent anomalously warm years. We applied these models to nearly 60,000 unobserved landing records and identified more than 500 instances in which vessels may have illegally fished in federal waters. This project was developed at the request of fisheries enforcement investigators, and now an automated system analyzes all new unobserved landings records to identify those in need of additional investigation for potential violations. Similar approaches informed by the spatial preferences of species landed may support monitoring and enforcement efforts in any number of partially observed, or even totally unobserved, fisheries globally.

Teplá období duben až říjen v Česku 1961 až 2022

The article compares selected periods in the warm half year based on the areal average of daily air temperature maxima and the number of summer and hot days from 1961 to 2022. Several characteristics have been proposed to evaluate the exceptionality of these periods. The highest M-day averages, averages for selected periods, and the number of summer and hot days in those periods were compared. For comparison, an assessment was also included on the total rainfall and total runoff for the territory of the Czech Republic.

Combined effects of Arctic tropospheric warming and La Niña events on enhanced Eurasian cold anomalies

This study investigates the combined effects of Arctic tropospheric warming and La Niña events on climate variations in Eurasia during boreal winter by utilizing the reanalysis data and the output of CMIP6 models. Results show that the “Warm Arctic-Cold Eurasia” pattern emerges with enhanced intensity under the combined effects compared with the individual effect of Arctic tropospheric warming or La Niña events. The significantly intensified Eurasian cold anomaly is observed in the north of Lake Baikal during the combined years. However, this cold anomaly shrinks substantially in warm Arctic years while shifting southwestward with a weaker intensity in La Niña years. Additionally, the winter atmospheric variability under the combined effects is much stronger than that under the individual effect of these two factors. Further investigation reveals that the La Niña event is probably crucial to dominating the basic distribution of winter temperature variability and the associated tropospheric circulation anomalies. Recent Arctic tropospheric warm anomalies are also essential, possibly amplifying the impact of the La Niña event on Eurasia through the weakened stratospheric polar vortex. These two factors jointly contribute to the enhanced “+−+” wave train that displays over mid-high latitudes under the combined effects. This “+−+” wave train exhibits alternative anticyclonic, cyclonic, and anticyclonic circulation anomalies over the Ural Mountains, Lake Baikal, and North Pacific, respectively. It guides wave energy from the Barents-Kara Seas (BKS) along the Ural Mountains to Lake Baikal and promotes the development of the Ural blocking anomaly that favors the intensified extreme cold temperature in Eurasia. The results of the CMIP6 models largely replicate some major features of the combined effects in the observations.

An analytical study of the climatic elements in Bazian region - Sulaymaniyah for the period from 1985 - 2022 and its impact on the planting dates of some crops

During a field study in Bazian Plain which is one of the most important agricultural areas in Sulaymaniyah it became clear that current scenario is linked to rapid climate change directly. Arid and semi-arid ecosystems are likely to be particularly affected by changes in wind speed and vapour pressure regimes, changes in those regimes may show from climate data that vapour pressure has clearly increased during these years. For instance, in January and February of 2017 wind speed reached 8 and 9 (m. sec.-1). Sulaymaniyah Meteorology Department reported a lesser speed of 0.1 (m. sec.-1) in the months 4, 5, 6 and 9, on average the greatest rates of 3.1 and 2.2 (m. sec.-1) in 1985 and 1992. on the other hand, in 1991 recorded the lowest rate of (1 m. sec.-1) amounts and times of precipitation during the study years, floods occurred in some seasons the dry seasons less than 300 (ml) were very few, while the remaining seasons were more than 450 (ml) rainfall amounts in the seasons 2006-2007, 2007-2008 and 2008-2009 were among the driest seasons during the years of the study Which was straight (66000, 87000, 86000) dunam. as the agricultural areas were reduced to their lowest levels, although the levels of precipitation were acceptable. The data gathered found that the average annual temperature rate has increased by over 1.3(°C) with the warmest year for this time being recorded in 2010 at 21.55(°C). Sunshine was the lowest in terms of the number of daylight hours in December with total annual averages for the period 1985-2022 for December being 184.4 (hours) 1996 was the lowest with 2.3 (hr.) and 2018 was also the second lowest with a value of 3.3 (hr.) During the decades of the study period, wheat growing seasons advanced mostly to November, and in recent decades (2011-2020) (2010-2009) 20 farmers plant in December to ensure rainfall.

Extreme marine heatwaves and cold-spells events in the Southern North Sea: classifications, patterns, and trends

In this study, we examined the long-term spatiotemporal trend of marine heatwaves (MHW) and marine cold spells (MCS) characteristics in the southern North Sea over the last four decades (1982-2021). We then estimated the difference between their annual mean values and the possible relationship with the large-scale climate modes of natural sea surface temperature (SST) and atmospheric variability using satellite SST data. The SST warming rate was 0.33 ± 0.06°C/decade and was associated with an increase in MHW frequency (0.85 ± 0.39 events/decade) and a decrease in MCS frequency (-0.92 ± 0.40 events/decade) over the entire period. We found a distinct difference between the annual mean values of MHW and MCS characteristics, with a rapid increase in total MHW days (14.36 ± 8.16 days/decade), whereas MCS showed an opposite trend (-16.54 ± 9.06 days/decade). The highest MHW frequency was observed in the last two decades, especially in 2014 (8 events), 2020 (5 events), and 2007 (4 events), which were also the warmest years during the study period. Only two years (2010 and 2013) in the last two decades had higher MCS frequency, which was attributed to the strong negative phase of the North Atlantic Oscillation (NAO). Our results also show that on the annual scale, both the East Atlantic Pattern (EAP) and the Atlantic Multidecadal Oscillation (AMO) play a more important role in the formation of the MHW in the southern North Sea than the other teleconnections (e.g., the NAO). However, the NAO made the largest contribution only in the winter. Strong significant (p < 0.05) positive/negative correlations were found between oceanic and atmospheric temperatures and the frequency of MHW/MCS. This suggests that with global warming, we can expect an increase/decrease in MHW/MCS occurrences in the future.

Regional polar warming linked to poleward moisture transport variability

Polar warming, ice melt and strong precipitation events are strongly affected by episodic poleward advection of warm and moist air (Woods and Caballero 2016 J. Clim. 29 4473–85; Wille et al 2019 Nat. Geosci. 12 911–6), which, in turn, is linked to variability in poleward moisture transport (PMT) (Nash et al 2018 J. Geophys. Res. Atmos. 123 6804–21). However, processes governing regional impacts of PMT as well as long-term trends remain largely unknown. Here we use an ensemble of state-of-the-art global climate models in standardized scenario simulations (1850–2100) to show that both the Arctic and the Antarctic exhibit distinct geographical patterns of PMT-related warming. Specifically, years with high PMT experience considerable warming over subarctic Eurasia and West-Antarctica (Raphael et al 2016 Bull. Am. Meteorol. Soc. 97 111–21), whereas precipitation is distributed more evenly over the polar regions. The warming patterns indicate preferred routes of atmospheric rivers (Woods and Caballero 2016 J. Clim. 29 4473–85), which may regionally enhance atmospheric moisture content, cloud cover, and downward longwave radiative heating in years with comparatively high PMT (Scott et al 2019 J. Clim. 32 665–84). Trend-analyses reveal that the link between PMT-variability and regional precipitation patterns will weaken in both polar regions. Even though uncertainties associated with intermodel differences are considerable, the advection of warm and moist air associated with PMT-variability is likely to increasingly cause mild conditions in both polar regions, which in the Arctic will reinforce sea-ice melt. Similarly, the results suggest that warm years in West-Antarctica disproportionally contribute to ice sheet melt (Trusel et al 2015 Nat. Geosci. 8 927–32), enhancing the risk of ice-sheet instabilities causing accelerated and sudden sea-level rise.

Effects of deterministic assembly of communities caused by global warming on coexistence patterns and ecosystem functions

Seasonal rhythms in biological and ecological dynamics are fundamental in regulating the structuring of microbial communities. Evaluating the seasonal rhythms of microorganisms in response to climate change could provide information on their variability and stability over longer timescales (>20-year). However, information on temporal variability in microorganism responses to medium- and long-term global warming is limited. In this study, we aimed to elucidate the temporal dynamics of microbial communities in response to global warming; to this end, we integrated data on the maintenance of species diversity, community composition, temporal turnover rates (v), and community assembly process in two typical ecosystems (meadows and shrub habitat) on the Qinghai-Tibet Plateau. Our results showed that 21 years of global warming would increase the importance of the deterministic process for microorganisms in both ecosystems across all seasons (R2 of grassland (GL) control: 0.524, R2 of GL warming: 0.467; R2 of shrubland (SL) control: 0.556, R2 of SL warming: 0.543), reducing species diversity and altering community composition. Due to environmental filtration pressure from 21 years of warming, the low turnover rate (v of warming: −3.13/-2.00, v of control: −2.44/−1.48) of soil microorganisms reduces the resistance and resilience of ecological communities, which could lead to higher community similarity and more clustered taxonomic assemblages occurring across years. Changes to temperature might increase selection pressure on specialist taxa, which directly causes dominant species (v of warming: −1.63, v of control: −2.49) primarily comprising these taxa to be more strongly impacted by changing temperature than conditionally (v of warming: −1.47, v of control: −1.75) or always rare taxa (v of warming: −0.57, v of control: −1.33). Evaluation of the seasonal rhythms of microorganisms in response to global warming revealed that the variability and stability of different microbial communities in different habitats had dissimilar biological and ecological performances when challenged with an external disturbance. The balance of competition and cooperation, because of environmental selection, also influenced ecosystem function in complex terrestrial ecosystems. Overall, our study enriches the limited information on the temporal variability in microorganism responses to 21 years of global warming, and provides a scientific basis for evaluating the impact of climate warming on the temporal stability of soil ecosystems.

АГРОНОМИЧЕСКИЕ РИСКИ ЗИМНЕГО ПЕРИОДА В УСЛОВИЯХ СОВРЕМЕННЫХ КЛИМАТИЧЕСКИХ ИЗМЕНЕНИЙ

The paper reveals the causes and consequences of unfavorable conditions for overwintering of winter grain crops on the example of the Moscow region. Unstable winter periods in the recent decades resulting from climate change have often led to the damage or loss of winter grain crops (winter wheat, winter rye, and triticale). Using the difference integral curve of average annual temperatures for the entire year, the growing season (May-September), and the period from September to April, including the winter season, it is shown that warm years and warm seasons have been generally observed since 1987. The sum of negative temperatures, snow depth, frost depth, the number of days with snow cover, the duration of cold periods with air temperatures below 0, -5, -10°C, etc. are analyzed for assessment of the changes in overwintering conditions.

Seasonal and spatial dynamics of the phytoplankton community in the Salish Sea, 2015–2019

A chemotaxonomic approach (HPLC) was used to determine the phytoplankton composition for the Salish Sea (coastal NE Pacific Ocean). The method was applied to 721 samples collected between 2015 and 2019. Microscopy was used to build then verify the CHEMTAX matrix and CHEMTAX outputs. Statistical methods were used to describe the patterns of phytoplankton composition over space and time. HPLC produced a more complete picture of the phytoplankton community than previous studies relying on microscopy. Nine taxonomic groups and four phytoplankton functional types were identified: (1) centric diatoms were present year round and were dominant during the spring bloom; (2) small flagellates (cryptophytes, haptophytes, prasinophytes) and pennate diatoms were ubiquitous but generally not bloom-forming; (3) large flagellates (dinoflagellates, dictyochophytes, raphidophytes) were mostly absent but with occasional very large blooms; and (4) cyanobacteria were rare. The pigment violaxanthin was diagnostic for Heterosigma akashiwo, which formed the largest bloom observed in our study (75 μg/L Tchl a). Cluster and network analyses identified three regions based on similarities in phytoplankton composition: (1) Juan de Fuca Strait and tidally mixed areas, (2) central Strait of Georgia, and (3) northern Strait of Georgia. Seasonally, significant differences in taxonomic composition occurred between winter and spring, and interannually between 2015 (a warmer year) and 2017 (a cooler year). Centric diatoms were associated with stronger vertical mixing, whereas haptophytes were associated with higher temperatures, reduced vertical mixing and lower nutrients. The CHEMTAX matrix we present is robust and useful for future studies in this area.

Quantitative attribution of the temperature associated with winter extreme cold events in China

Extreme cold events exert enormous impacts on the ecosystems and human health. A quantitative attribution analysis of the surface temperature anomalies associated with extreme cold events in China is conducted using an updated version of the coupled atmosphere-surface climate feedback response analysis method. For both extreme warm and cold years, the effects of anomalous surface albedo, water vapor, atmospheric dynamics, and aerosols are the major positive contributors, and the processes associated with surface dynamics provide a major negative effect. Specifically, the effect of surface albedo (water vapor) is directly linked to the change in local snow cover (precipitable water) over China. More local snow cover (precipitable water) provides a cooling (warming) effect and vice versa. The process associated with atmospheric dynamics exhibits an asymmetric contribution for the extreme warm and cold years. It provides a warming effect over most of China in the extreme warm years, which is possibly related to the nation-wide warm air advection. On the other hand, the effect of atmospheric dynamics displays large regional and year-to-year variations for the cold cases. In addition, a considerable impact of anthropogenic aerosols is detected over central-southern China, which is possibly related to the emission reduction policies in China since 2013. Although clouds show only a moderate impact on the national-averaged temperature anomalies, they provide a considerable effect over southern China.

Triggers for multiple glacier detachments from a low-angle valley glacier in the Amney Machen Range, eastern Tibetan Plateau

Large-scale ice avalanches initiated from low-angle glaciers (also known as glacier detachment) remain a scarcely studied and poorly understood phenomenon. Here we re-evaluated the repeat glacier detachments of a low angle (~14°) surging valley glacier in the Amney Machen Range, eastern Tibetan Plateau. Four glacier detachments recorded over a 15-year period (2004–2019) are described in detail based on the combination of satellite image analyses, additional terrain profile analyses and field data. To identify what triggered these high magnitude events, the glacier fluctuations, seismicity, lithology, and regional climate were examined. We find that the factors favouring glacier detachments were anomalous warming, subglacial hydrology, repeated glacier surging, a soft glacier bed, and ice-rock loading from the glacier headwall, though the relative influence of each factor varied in the four events we studied. We confirmed the observation of Paul (2019) that additional ice-rock debris loadings from the headwall were the most important factor for all events. The 2004 event probably was a delayed response to ice-rock loading during the preceding months. The latter three events may have been affected by short-term climate anomalies. The events of 2007 and 2016 were associated with anomalously high temperature: abrupt warming preceded the 2007 event and 2016 was the warmest year on record. The 2019 event followed sustained precipitation and high summer temperatures. Based on the spatial patterns in glacier change, we suggest that climate warming played a limited role in initiation.

Drivers of soil nitrogen availability and carbon exchange processes in a High Arctic wetland

Increased soil nutrient availability, and associated increases in vegetation productivity, could create a negative feedback between Arctic ecosystems and the climate system, thereby reducing the contribution of Arctic ecosystems to future climate change. To predict whether this feedback will develop, it is important to understand the environmental controls over nutrient cycling in High Arctic ecosystems and their impact on carbon cycling processes. Here, we examined the environmental controls over soil nitrogen availability in a High Arctic wet sedge meadow and how abiotic factors and soil nitrogen influenced carbon dioxide exchange processes. The importance of environmental variables was consistent over the 3 years, but the magnitudes of their effect varied depending on climate conditions. Ammonium availability was higher in warmer years and wetter conditions, while drier areas within the wetland had higher nitrate availability. Carbon uptake was driven by soil moisture, active layer depth, and variability between sampling sites and years ( R2 = 0.753), while ecosystem respiration was influenced by nitrogen availability, soil temperature, active layer depth, and sampling year ( R2 = 0.848). Considered together, the future carbon dioxide source or sink potential of high latitude wetlands will largely depend on climate-induced changes in moisture and subsequent impacts on nutrient availability.

Magnetic Seed Treatment Modulates Phenolic and Fatty Acid Metabolism of Sunflower under Water Scarcity

Environmental and anthropogenic activities are pushing the earth towards warmer years, which is reducing agricultural land and causing water scarcity. It is well documented that sunflower (being drought tolerant) crops can be grown under water deficit conditions with some additional supportive priming applications to compensate for drought-induced challenges. However, finding the most efficient and eco-friendly priming tools is always a top priority among researchers to improve plant growth, adaptive traits, and productivity. In this study, an experiment was performed on oil-producing crops (sunflower) using seed magnetic treatment. The seeds were subjected to 0.1, 0.2, and 0.3 Tesla for 20 min, respectively. Plants were exposed to water limitation (100 and 50%) after 30 days of germination. Sunflower showed its tolerance to water limitation by maintaining the majority of growth parameters, nutritive value, metabolizable energy, and higher proline content. Nevertheless, a reduction in the achene number per capitulum, capitulum weight, chlorophyll, catalase activity, unsaturated to saturated fatty acids, anthocyanin, and hydroxyl derivatives of cinnamic acid supported our hypothesis about the need for some supportive techniques. Better metabolic adjustment and percentage of oil yield were manifested by 0.3 T magnetic seed treatment, which was used for phenolic and fatty acid profiling. To conclude, magnetic treatment of seeds may improve their primary metabolic capacity and antioxidation potential, which in turn may activate their secondary metabolism as evidenced by an excess of gallic acid, quercetin, benzoic acid, curcumin acid, sinapic acid, and chlorogenic acid.

Influence of extreme cold and warm oceanographic events on larval fish assemblages in the southern region of the California Current

The larval fish community in the southern region of the California Current (CC) was analyzed to test the hypothesis of a northward expansion of tropical species for the summer-fall seasons of La Niña (LN) 2010-2011, The Blob 2014, and El Niño (EN) 2015-2016. Interannual temperature anomalies (-5 to +2°C), as well as decreases in chlorophyll a (68%) and zooplankton density (71%), resulted in dramatic changes in the larval fish community, such as an 82% decline in larval fish density, unprecedented for the CC. Tropical species richness increased in the north by 46%, while temperate species decreased by 65% in the south. Mesopelagic species richness and relative abundance increased in the north by 53 and 92%, respectively. In the south, the species richness of the demersal component increased up to 39%, although demersal species were co-dominant with mesopelagic species, accounting for 47% of the relative abundance compared to 49% for the mesopelagic species. The magnitude of the changes in the community was unparalleled when compared with other warming events, such as EN 1983-1984 or EN 1997-1998. The differences were probably related to the presence of The Blob, which favored the transport of oceanic species into the neritic region of the CC. In both cold and warm years, fronts and mesoscale eddies in the middle part of the Baja California Peninsula represented barriers to the latitudinal distribution of species, even during intense tropicalization processes, since no latitudinal extensions in species distribution occurred.

Little directional change in the timing of Arctic spring phenology over the past 25 years

With the global change in climate, the Arctic has been pinpointed as the region experiencing the fastest rates of change. As a result, Arctic biological responses-such as shifts in phenology-are expected to outpace those at lower latitudes. 15 years ago, a decade-long dataset from Zackenberg in High Arctic Greenland revealed rapid rates of phenological change.1 To explore how the timing of spring phenology has developed since, we revisit the Zackenberg time series on flowering plants, arthropods, and birds. Drawing on the full 25-year period of 1996-2020, we find little directional change in the timing of events despite ongoing climatic change. We attribute this finding to a shift in the temporal patterns of climate conditions, from previous directional change to current high inter-annual variability. Additionally, some taxa appear to have reached the limits of their phenological responses, resulting in a leveling off in their phenological responses in warm years. Our findings demonstrate the importance of long-term monitoring of taxa from across trophic levels within the community, allowing for detecting shifts in sensitivities and responses and thus for updated inference in the light of added information.