Maximum Summer Temperatures Research Articles

Temperature and carotid intima-medial thickness: The coronary artery risk development in young adults (CARDIA) study

BackgroundFew studies have examined the role of long-term (≥1 year) ambient temperature with quantitative traits of early-stage cardiovascular disease (CVD) such as carotid intima-medial thickness (cIMT). Our objective was to examine associations between temperature and cIMT, a measure of subclinical atherosclerosis. MethodsThis study examined data from 3257 participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study, aged 18–30 years at baseline (1985–1986). We used North America Land Data Assimilation System data to derive 12 metrics of ambient daily temperature: Mean, minimum, maximum, and standard deviation temperature in summer, winter, and year-round. We examined associations with cIMT in separate cross-sectional multivariable models at CARDIA year 20 (2005–2006) as well as stratified analyses by self-reported race and sex. We also prospectively examined cumulative temperature by summing temperature variables from Y0-Y20. ResultsAccounting for study center attenuated most associations between cIMT and ambient temperature exposure, but the winter standard deviation remained associated (overall β = −0.0104 mm/°C, 95 % CI: −0.0150 to −0.0059). Minimum summer temperature was also associated with cIMT in the overall study population (β = 0.0020 mm/°C, 95 % CI: 0.0005–0.0035). Associations did not differ substantially by race, but women had stronger associations than men. Cumulative temperature was not associated with cIMT. ConclusionsOur findings suggest a role of geography, particularly ambient temperature in cIMT. Future research to address potential residual confounding is necessary, but if validated these findings have implications for policy and strategies to mitigate health impacts of climate change.

Interannual Variability in Seed Germination Response to Heat Shock in Cistus ladanifer

Mediterranean climates, characterised by hot and dry summers, have predictable fire regimes, and many species with physical seed dormancy (PY) thrive after wildfires. While it is well known that PY is released after heat shock in these species, intraspecific variation in seed response to heat is less understood. This research explores, for the first time, the variability in the traits of Cistus ladanifer seeds from the same central Spain population over eight years. It examines seed germination and viability under different heat shocks and the relationships among seed traits and climatic variables. While the response to heat shock remained constant over the years studied, achieving the highest germination percentages after heat shock at 100 °C, seed germination varied between years, and environmental conditions affected seed traits. Seed moisture content was negatively correlated with the maximum summer temperatures, and seed viability was positively related to annual precipitation. Germination at 100 °C was lower in warmer years as more seeds did not break their PY. In conclusion, despite the fact that PY appears to be genetically determined, it also depends on the environmental conditions experienced by the mother plant. This interannual phenotypic variability may help Cistus ladanifer to cope with the increasingly unpredictable conditions imposed by climate change.

Unraveling the ecological niche signals of Verticillium dahliae: Insights from Mediterranean landscapes.

Verticillium wilt (VW), caused by the soil-borne plant pathogenic fungus Verticillium dahliae, is a major disease impacting olive crops globally. In view of the lack of effective post-infection treatments, exclusion and avoidance strategies are essential in disease management. Assessing the risks posed by this pathogen is essential to prevent the spread and to ensure selection of suitable sites for new plantations. This study aimed to elucidate the environmental factors driving V. dahliae establishment in the Andalusia region, in southern Spain, an emblematic Mediterranean landscape for olive cultivation. To this end, we explored ecological niche signals for this fungal pathogen by analyzing 62 environmental variables across 1.6 million hectares dedicated to olive and cotton cultivation, using a 15-yr survey data on VW incidence on presence-absence from both olive and cotton fields. To ensure robust identification of ecological niche signals, we employed randomization-based, non-parametric univariate tests to compare presence records with the broader sampling universe (including absence records). Our findings identified key environmental variables that are associated significantly with V. dahliae presence, including temperature range seasonality (including mean diurnal and annual ranges), summer temperature (maximum of the warmest month, mean of the warmest quarter), and moisture and water availability (near-surface humidity, potential evapotranspiration, vapor pressure) as core niche variables for V. dahliae. Our results replicated the pathogen's known distribution, identifying the Guadalquivir Valley as a particularly high-risk area in view of its mild winters and distinct rainy seasons, providing new insights into the specific environmental conditions that facilitate the pathogen's survival and spread. Furthermore, this study introduces a novel approach to niche modeling that prioritizes variables with consistent effects and significant impact on the presence and distribution of V. dahliae and identifies potential data artifacts. This approach enhances our understanding of ecological requirements in V. dahliae and informs targeted management strategies.

Warming summer temperatures are rapidly restructuring North American bumble bee communities.

A rapidly warming climate is driving changes in biodiversity worldwide, and its impact on insect communities is critical given their outsized role in ecosystem function and services. We use a long-term dataset of North American bumble bee species occurrences to determine whether the community temperature index (CTI), a measure of the balance of warm- and cool-adapted species in a community, has increased given warming temperatures. CTI has increased by an average of 0.99°C in strong association with warming maximum summer temperatures over the last 30 years with the areas exhibiting the largest increases including mid- to high latitudes as well as low and high elevations-areas relatively shielded from other intensive global changes. CTI shifts have been driven by the decline of cold-adapted species and increases in warm-adapted species within bumble bee communities. Our results show the pervasive impacts and ecological implications warming temperatures pose to insects.

Amplification of temperature extremes in Arabian Peninsula under warmer worlds

The Paris Agreement and the Special Report on Global Warming of 1.5 °C from the Intergovernmental Panel on Climate Change (IPCC) highlighted the potential risks of climate change across different global warming levels (GWLs). The increasing occurrence of extreme high-temperature events is linked to a warmer climate that is particularly prevalent in the Arabian Peninsula (AP). This study investigates future changes in temperatures and related extremes over AP, under four GWLs, such as 1.5 °C, 2.0 °C, 3.0 °C, and 4.0 °C, with three different Shared Socioeconomic Pathways (SSPs: SSP1-2.6, SSP2-4.5, and SSP5-8.5). The study uses high-resolution datasets of 27 models from the NASA Earth Exchange Global Daily Downscaled Projections of the Coupled Model Intercomparison Project Phase 6 (NEX-GDDP-CMIP6). The results showed that the NEX-GDDP-CMIP6 individual models and their multi-model means reasonably captured the extreme temperature events. The summer maximum and winter minimum temperatures are projected to increase by 0.11–0.67 °C and 0.09–0.70 °C per decade under the selected SSPs. Likewise, the projected temperature extremes exhibit significant warming with varying degrees across the GWLs under the selected SSPs. The warm temperature extremes are projected to increase, while the cold extremes are projected to decrease under all GWLs and the selected SSPs. Overall, the findings provide a comprehensive assessment of temperature changes over AP in response to global warming, which can be helpful in the development of climate adaptation and mitigation strategies.

Meteorological data from Badwater, Death Valley National Park 1998 to 2019

AbstractWe installed a meteorological recording system at Badwater (elev. −75 m), the lowest point in Death Valley, California and recorded data over the period 1998–2019. A second station (the Outhouse Station) was established nearby from 2014 to 2019. Here, we report on and publicly archive the data from these two stations. Of interest was the comparison between two air temperature measurements at the Badwater Station, the first with an aspirated platinum resistance temperature device and the second with a thermistor probe in a passive sun shield. During the hottest periods of the summer when temperatures were typically between 30°C at night and 50°C daily peak, the passively shielded sensor indicated up to 0.5°C warmer than the aspirated temperature sensor due to radiative effects. The data suggest a correction for radiative heating of (T–35)/30, for T > 35°C, where, T, is the uncorrected temperature reading of a passively shielded sensor subtracted after any calibration at lower temperatures. Our station was the first precision temperature measurements at Badwater. A longer record exists for the reporting station near the visitor's centre at the Furnace Creek. The summer temperature maxima at the Badwater site correlate well with the values the same day from the Furnace Creek site. The daily maximum temperatures in winter at the Badwater site appear to be about 1°C lower than at the Furnace Creek site. The largest differences are in the minimum temperatures for which the Badwater site averages about 2–3°C warmer than the Furnace Creek site.

Reconstructed Late Summer Maximum Temperatures for the Southeastern United States From Tree‐Ring Blue Intensity

AbstractOver recent decades, the southeastern United States (Southeast) has become increasingly well represented by the terrestrial climate proxy record. However, while the paleo proxy records capture the region's hydroclimatic history over the last several centuries, the understanding of near surface air temperature variability is confined to the comparatively shorter observational period (1895‐present). Here, we detail the application of blue intensity (BI) methods on a network of tree‐ring collections and examine their utility for producing robust paleotemperature estimates. Results indicate that maximum latewood BI (LWBI) chronologies exhibit positive and temporally stable correlations (r = 0.28–0.54, p < 0.01) with summer maximum temperatures. As such, we use a network of LWBI chronologies to reconstruct August‐September average maximum temperatures for the Southeast spanning the period 1760–2010 CE. Our work demonstrates the utility of applying novel dendrochronological techniques to improve the understanding of the multi‐centennial temperature history of the Southeast.

Contrasting water-use strategies to climate warming in white birch and larch in a boreal permafrost region.

The effects of rising atmospheric CO2 concentrations (Ca) with climate warming on intrinsic water-use efficiency and radial growth in boreal forests are still poorly understood. We measured tree-ring cellulose δ13C, δ18O, and tree-ring width in Larix dahurica (larch) and Betula platyphylla (white birch), and analyzed their relationships with climate variables in a boreal permafrost region of northeast China over past 68years covering a pre-warming period (1951-1984; base period) and a warm period (1985-2018; warm period). We found that white birch but not larch significantly increased their radial growth over the warm period. The increased intrinsic water-use efficiency in both species was mainly driven by elevated Ca but not climate warming. White birch but not larch showed significantly positive correlations between tree-ring δ13C, δ18O and summer maximum temperature as well as vapor pressure deficit in the warm period, suggesting a strong stomatal response in the broad-leaved birch to temperature changes. The climate warming-induced radial growth enhancement in white birch is primarily associated with a conservative water-use strategy. In contrast, larch exhibits a profligate water-use strategy. It implies an advantage for white birch over larch in the warming permafrost regions.

Variation in the strength and stationarity of southern longleaf pine seasonwood climate-growth relationships

Climate change is predicted to cause asymmetric warming and increased precipitation variability across different seasons. These changes and their effects may be captured in subannual seasonwood measures of tree growth (i.e., earlywood, latewood). Longleaf pine is a foundational tree species throughout the broad southeastern U.S. Its latewood growth may be more variable and sensitive to climate change than earlywood, but prior studies have geographical and ecological sampling limitations. Here, we use dendroecological methods to develop ring-width and seasonwood (earlywood, latewood, and adjusted latewood) chronologies and analyze climate-growth relationships for longleaf pine from eight sites in the Southern Coastal Plain of Florida, USA. Sites spanned a range of environmental conditions to generate an ecologically representative dataset. We evaluated chronology strength and variability and determined monthly and seasonal correlations with precipitation and temperature. We furthermore evaluated climate-growth stationarity using a moving response function and bootstrapped transfer function stability tests. We found adjusted latewood chronologies were most climatically sensitive although totalwood chronologies had higher interseries correlations. Totalwood measurements were more variable than early- or latewood year to year. Tree growth was positively correlated with summer precipitation at six out of eight sites and negatively correlated with late summer maximum temperatures at six out of eight sites. Negative relationships between growth and maximum temperature occurred earlier in the year at southern sites and the positive effect of June precipitation on tree growth was notable, found at six out of eight sites. However, the strength and significance of climate-growth relationships were non-stationary through space and time, with shifts largely occurring post-1950s. Longleaf pine at its southern range extent was less sensitive to climate than more northern populations, which may indicate non-linear responses to warming captured at the species’ range margin. Our results highlight dynamic climate-growth relationships related to the broad range of environmental conditions where longleaf pine is found.

Influence of forest age, tree size, and climate factors on biomass and carbon storage allocation in Chinese fir forests

Biomass and carbon allocation among plant organs are influenced by the individual tree's development and climate conditions. Chinese fir forests play an important role in the carbon cycle and climate change mitigation in China. Understanding how forest age, tree size, and climate factors affect biomass and carbon allocation in Chinese fir forests is crucial to fully utilize the carbon sequestration potential. We analyzed the response of Chinese fir biomass allocation fractions (BAFs) and carbon stock allocation fractions (CAFs) to forest age, tree size, and climate factors, utilizing field survey data on biomass of 93 trees in Fujian, Sichuan, Guangxi, and Jiangxi provinces and carbon storage of 40 trees in Fujian, Sichuan, and Guangxi provinces in China. Our results showed that BAFs depend on individual development. In young and middle-aged forests, BAFs were unaffected by diameter at breast height (DBH), whereas branch and root biomass fractions displayed a significant positive correlation with DBH, and stem biomass fraction displayed a negative correlation with DBH in mature forests. Carbon concentration exhibited substantial variation among distinct components and regions. Overall, the carbon concentration of each organ ranked as Guangxi > Sichuan > Fujian. BAFs of dominant trees are almost independent of climatic factors, while suppressed trees will alter their strategies for biomass allocation in response to climate change. Stem biomass fraction exhibited a significant positive correlation with maximum growing season temperature, mean summer temperature, and maximum summer temperature, whereas leaf biomass fraction showed the opposite trend. Under future climate warming, Chinese fir will allocate more biomass to the stem, at the expense of leaf biomass. These findings support the idea that biomass allocation patterns serve as adaptive patterns to address fluctuations in internal and external conditions. The interaction between climate factors and tree size shows promise for predicting trends in forest biomass and carbon accumulation in the context of future climate change.

Present day and future urban cooling enabled by integrated water management

The process of urbanisation has increased public health risks due to urban heat, risks that will be further exacerbated in future decades by climate change. However, the growing adoption of integrated water management (IWM) practices (coordinated stormwater management of water, land, and resources) provides an opportunity to support urban heat amelioration through water supply provision and irrigated and vegetated infrastructure that can provide cooling benefits. This study examines the thermal impacts of future implementations of IWM for nine Australian cities based on a review of Government policy documents in the present and over two future time frames (2030 and 2050) under different greenhouse gas emission scenarios (SSPs 1.2-6, 3.7-0 and 5.8-5). Statistical analysis of the future climate data using historical data shows that future warming is nuanced, with changes variable in both time and place, and with extremes becoming more pronounced in future. We have developed a unique approach to morph the future climate projections onto historical data (derived from the ERA5 Reanalysis product) for the 2010-2020 period. Additionally, we use locally appropriate Local Climate Zones (LCZs) for Australian cities, resulting from a holistic and global approach that is widely adopted by the urban climate modelling community. We developed scenarios for business-as-usual as well as implementation of moderate and high levels of IWM across each of the Australian LCZs and modelled them using TARGET (The Air temperature Response to Green infrastructure Evaluation Tool). Results generated at the LCZ level are aggregated to Australian statistical areas (SA4, the largest sub-city area) and city-wide levels. The thermal impacts associated with the various degrees of IWM were marked and geographically differentiated, depending on the climatic characteristics of the various cities. For the current climate, high IWM intervention provided reductions in annual mean daily maximum temperature ranging from -0.77°C in Darwin, up to -1.86°C in Perth. Generally, the drier southern cities of Sydney, Canberra, Albury, Melbourne, Adelaide, and Perth produced the greatest thermal response to implementation of IWM and the more tropical cities with higher rainfalls the least response. For some southern cities cooling was > -3.0°C at the time of maximum summer temperatures. Interestingly high levels of IWM in winter produced modest warming of minimum overnight temperatures, especially for the cooler southern cities. The cooling benefits of IWM were seen across all future climate scenarios and are a real opportunity to offset-projected temperature increases resulting from climate change.

Forestry impacts on stream flows and temperatures: A quantitative synthesis of paired catchment studies across the Pacific salmon range

Abstract Forestry is pervasive across temperate North America and may influence aquatic environmental conditions such as flows and temperatures, as well as important species such as Pacific salmon (Oncorhynchus spp.). While there have been many large‐scale forestry experiments using paired catchment designs, these studies have yet to be quantitatively synthesized. Thus, it remains unclear whether forestry impacts are consistent, context‐dependent or unpredictable. This study aims to quantitatively synthesize forestry impacts on streamflow and temperature, through a systematic review and synthesis of paired catchment studies across the range of Pacific salmon. Specifically, we investigated whether generalizable relationships exist between forestry intensity (percent watershed harvested) and impacts to streamflow and temperature. We also examined whether watershed features (climate, hydrology and lithology) and harvest method mediated forestry impacts. We extracted information from 35 unique paired‐catchments from California to Alaska. Forestry had strong impacts on peak and low flows and maximum summer water temperatures, but responses were quite variable. Across all catchments, forestry elevated peak flows ~20% (n = 31 catchments), reduced low flows ~25% (n = 13 catchments) and increased maximum summer temperatures ~15% (n = 35 catchments) on average. However, these impacts were variable and were not predictable based on forestry intensity, thus broader stressor–response relationships were not supported. Forestry impacts on peak flows and maximum summer temperatures varied spatially. Peak flow impacts increased with northward latitude and temperature impacts decreased with eastward longitude. However, the magnitude of impacts were unrelated to other watershed attributes, which included climate (precipitation and aridity), rain versus snow hydrology, elevation and bedrock lithology. Harvest method and riparian buffer presence also had no detected effects on forestry impacts across studies and statistical models explained a low proportion of variation overall. Collectively, our results indicate that forestry can have substantial impacts on key environmental conditions; however, the magnitude of impact was variable and could not be clearly linked to easily measured watershed characteristics. This implies that forestry impacts may not be broadly predictable. Probabilistic risk models based on distributions of potential impacts may therefore be more useful for watershed management in data‐poor situations.

Annual performance study and optimization of concentrated photovoltaic-phase change material system

Concentrated photovoltaic (CPV) has the superiority of high efficiency and low cost. But the waste heat generated in PV cell has great effect on its performance. To study and optimize the real time photoelectric conversion performance, a two-dimensional PV model was firstly established. The impacts of concentration ratio and PV temperature on efficiency were investigated, and the correlation was derived. Based on that, phase change material (PCM) was utilized to realize temperature control of PV cell and a three-dimensional transient model for CPV-PCM system was established. The impacts of geometric parameters on the transient and annual performance were evaluated under the real climate conditions. The results show that concentration ratio has significant impacts on both thermal and electrical performance, and there exists an optimal concentration ratio to maximize the PV efficiency. At last, the system structure was optimized by orthogonal experimental method with annual average efficiency as the target. The optimal parameters combination was derived with concentration ratio of 300, PCM layer height of 60 mm, and fin number of 7. The validation results show that after optimizing, the maximum PV temperatures in summer and autumn are reduced by 9.4 °C and 7.4 °C, respectively, and the annual average efficiency of the system is improved by 1.83%.

A High‐Resolution, Daily Hindcast (1990–2021) of Alaskan River Discharge and Temperature From Coupled and Optimized Physical Models

AbstractWater quality and freshwater ecosystems are affected by river discharge and temperature. Models are frequently used to estimate river temperature on large spatial and temporal scales due to limited observations of discharge and temperature. In this study, we use physically based river routing and temperature models to simulate daily discharge and river temperature for rivers in 138 basins in Alaska, including the entire Yukon River basin, from 1990–2021. The river temperature model was optimized for ice free months using a surrogate‐based model optimization method, improving model performance at uncalibrated river gages. A common statistical model relating local air and water temperature was used as a benchmark. The physically based river temperature model exhibited superior performance compared to the benchmark statistical model after optimization, suggesting river temperature model optimization could become more routine. The river temperature model demonstrated high sensitivity to air temperature and model parameterization, and lower sensitivity to discharge. Validation of the models showed a Kling‐Gupta Efficiency of 0.46 for daily river discharge and a root mean square error of 2.04°C for daily river temperature, improving on the non‐optimized physical model and the benchmark statistical model, which had root mean square errors of 3.24 and 2.97°C, respectively. The simulation shows that rivers in northern Alaska have higher maximum summer temperatures and more variability than rivers in the Central and Southern regions. Furthermore, this framework can be readily adapted for use across models and regions.

ASSESSMENT OF ECOLOGICAL PROCESSES IN THE SVIYAGA RIVER (ULYANOVSK REGION)

The Sviyaga River is a water resource, and a recreational facility. It is rich in fish, therefore the assessment of ecological processes in the Sviyaga river is relevant and has theoretical and practical significance. The relevance and practical significance of research is increasing due to the plans to use the Sviyaga river bays for aquaculture development.
 The purpose of the study was to examine the nature and direction of ecological processes in the Sviyaga River bays on the territory of the Ulyanovsk region.
 Materials and Methods. The assessment of the bay water quality was carried out according to organoleptic, hydrochemical and hydrobiological parameters.
 Results. Organoleptic water parameters in both bays met the requirements for natural waters. The maximum water temperature in summer reached 24–26 ºС, the average temperature was 20.5 ºС. The amount of dissolved oxygen (6.5 mg/l) corresponded to the optimal values for the life of many fish species, and pH level showed weak water alkalinity. Hydrochemical bay water composition indicated high organic pollution. In both bays, and in the Sviyaga river itself, the content of heavy metals and petroleum products was several times higher than the threshold limit value. BOD5 level in the bays significantly exceeded the limit values. BOD20 and chemical oxygen demand exceeded the standards four times. The results of a microbiological study revealed significant water contamination with Escherichia coli. The species composition of the aquatic phytocenosis in both bays largely corresponded to the Sviyaga River phytocenosis structure. However, the bays are characterized by plant species and ecological processes that indicate the initial stages of their waterlogging.

Climate warming is significantly influenced by rising summer maximum temperatures: insights from tree-ring evidence of the Western Tianshan Mountains, China

Climate warming is significantly influenced by rising summer maximum temperatures: insights from tree-ring evidence of the Western Tianshan Mountains, China

Variations in Seed Dormancy Occurrence and Their Classifications in Thirteen Actinidia Species

As differences in seed dormancy between Actinidia species have not been reported previously, in this study we characterized the variation in the dormancy of seeds in 13 kiwifruit species that originated from different regions of China and Taiwan, and for which mature plants are now growing in New Zealand orchards. Dormancy-breaking treatments, including cold-moist stratification, seed coat scarification and soaking in water and gibberellic acid (GA3), were tested for their efficacy in alleviating dormancy and improving final germination and germination rates. In addition, we assessed seed viability using RNA integrity analysis to distinguish dead seeds from dormant seeds. This study identified that dormancy type in Actinidia seeds is species-specific and can be morphological, morphophysiological or a combination of physiological and physical, and that seed RNA integrity is a useful metric to incorporate into seed dormancy studies. Our results also suggest that species originating from colder climates that experience large differences between winter minimum and summer maximum temperatures exhibit physiological dormancy and require cold-moist stratification, contrasting with species originating in milder climates. Interestingly, although not all seeds from all the species were dormant, the proportion of dormant seeds in each species did not correlate to the climatic data of the region from which they originated. These findings provide new insights into mechanisms of seed dormancy in kiwifruit.

Influence of interactive effects on long-term population trajectories in multispecies reintroductions.

Reintroduced populations are typically considered to progress through establishment, growth, and regulatory phases. However, most reintroduction programs do not monitor intensively enough to test this conceptual model. We studied population indices derived from track activity of 4 threatened species (greater bilby [Macrotis lagotis], burrowing bettong [Bettongia lesueur], greater stick-nest rat [Leporillus conditor], and Shark Bay bandicoot [Perameles bougainville]) over 23years after multiple reintroductions of each species in arid Australia. We compared population trajectories among species and investigated the effect of time and environmental variables. All species bred immediately after release, and the growth phase lasted 3-16years, varying markedly among but not within species. The end of the growth phase was characterized by an obvious peak in population density followed by either a catastrophic decline and sustained low density (bettongs), a slow decline to extirpation after 20years (stick-nest rat), or a slight decline followed by irregular fluctuations (bilby and bandicoot). Minor fluctuations were related to environmental variables, including 12-month cumulative rainfall and lagged summer maximum temperatures. Three of the 4 species did not reach a regulation phase, even after 23years, possibly due to interspecific competition and trophic cascades triggered by predator removal and multispecies reintroductions. Bilbies and bandicoots exhibited a second growth phase 18years after reintroduction, likely caused by high rainfall and increased resources following the population crash of overabundant bettongs. Our results suggest that assemblages within multispecies reintroductions demonstrate high variability in population trajectories due to interactive effects. Intensive monitoring to assess population viability may require decades, particularly where multiple species are reintroduced, release sites are confined, and the climate is unpredictable. Intensive monitoring also allows for adaptive management to prevent precipitous population declines. Practitioners should not assume reintroduced species pass through predictable postrelease population phases or that viability is assured after a certain period.

Evaluation of climate change impact on plants and hydrology

Climate change (CC) is the menace of the hour impacting every facet of human existence. Regional CC and its impact studies are crucial in that they contribute to global change. The current study aims to investigate the prevalence of CC in Charsadda, Pakistan and its impact on vegetation and hydrology of the region to understand microclimate variability contribution to global CC. Utilizing local climate data for 20 years (2001–2020), Modified Mann-Kendall and Sen’s Slope statistics were employed to determine monthly and seasonal trends in climate variables. Significant changing climate variables were regressed on Moderate resolution Imaging Spectroradiometer (MODIS) satellite dataset viz. normalized difference vegetation index (NDVI). Due to the prominent climate factor impacting vegetation, NDVI was further correlated to MODIS land surface temperature (LST). Floods being the conspicuous climate calamity were mapped for 2005 and 2010 using satellites Landsat 5 and 7 dataset viz. normalized difference water index (NDWI) with flood risk assessment by watershed delineation. The findings revealed significant (p < 0.05) variability in climate variables (average monthly and summer maximum temperature, and average monthly and summer precipitation) that are driving CC and impacting vegetation and hydrology in the region. Temperature and solar radiation affect NDVI adversely while precipitation and relative humidity has positive impact on vegetation. NDVI varied greatly spatiotemporally, often increasing but worsening in some areas (Shabqadar, Abazai, Palai and Charsadda city with NDVI = 0.1–0.3) of the study region as a result of extreme weather events. Temporally, NDVI improved with an overall positive trend with a stage (2007–2016) of noticeable zigzag fluctuation. Spatial grids with higher LST (>40°C) were either devoid of or with sparse NDVI (<0.3) presenting global warming as peril to vegetation. NDWI maps (2005, 2010 floods) indicate that after floods wreaked havoc on the region altering the vegetation pattern revealing heavy irregular precipitation as the next to temperature in jeopardizing vegetation of the region. Lower elevation regions along the Swat and Kabul Rivers with a greater risk of flooding were identified by watershed delineation. The study suggests that local governments and stakeholders implement CC mitigation strategies and plans for vegetation restoration, flood alerts with post-flood management for regional sustainable development.

Monitoring the Extraordinary Ephemeral Emergence of Myriophyllum spicatum L. in the Coastal Lagoon Albufera of Valencia (Spain) and Assessing the Impact of Environmental Variables Using a Remote Sensing Approach

The Albufera of Valencia, a Mediterranean coastal lagoon, has been in a turbid state since 1974, with only four episodes of temporary water transparency in spring. Despite its average depth of 1 m and oligohaline waters, excessive turbidity, fish grazing, and toxic compounds have inhibited submerged macrophyte growth. In spring 2018, a significant area of Myriophyllum spicatum emerged and exhibited significant density until its complete disappearance in August 2018. Using Sentinel-2 and Landsat-8 imagery, we monitored water quality variables and vegetation density during these months. Our study revealed the first unique occurrence of M. spicatum in more than 40 years. A period of increased transparency from summer 2017 compared to previous years seems to be the cause of this appearance, while high summer temperatures caused its disappearance. While improving water quality may help restore submerged macrophyte meadows, our results suggest that summer maximum temperatures may inhibit recovery. Remote sensing, particularly the NDVI index, proved successful in monitoring aquatic vegetation and understanding species-environment relationships. This methodology can enhance future monitoring efforts for macrophyte colonization and expand knowledge of their occurrence and causes of disappearance in this and other similar areas.