Effect of the extreme summer heat waves on isolated populations of two orophitic plants in the north Apennines (Italy)

AbstractThis study applies the maximum temperatures at more than 2000 Chinese stations to investigate the dominant modes of China summer heat waves (HWs). The first empirical orthogonal function (EOF) mode of the HW days reflects an increased frequency of HWs in northern China (NC), while the second and third modes represent two distinct interannual modes, with key regions over the Yangtze River valley (YRV) and southern China (SC), respectively. The NC HWs are possibly associated with the Atlantic–Eurasian teleconnection, showing zonally propagating wave trains over the North Atlantic and Eurasian continent. The YRV HWs are proposed to be linked to the North Atlantic Oscillation, which may trigger a southeastward-propagating wave train over northern Russia and East Asia that results in a high pressure anomaly over the YRV. The SC HWs are obviously dominated by the Indian Ocean and northwest Pacific warm SSTs owing to the transition from the preceding El Niño to La Niña, which excites above-normal highs over SC. The anomalously high pressures over NC, the YRV, and SC are usually accompanied by descending air motions, clear skies, decreased precipitation, and increased solar radiation, which jointly cause a drier and hotter soil condition that favors the emergence of HWs. The GFDL HiRAM experiments are able to reproduce the historical evolution of NC and SC HWs, but fail to capture the YRV HWs. The correlation coefficient between model PC1 (PC2) and observed PC1 (PC3) for the period of 1979–2008 is 0.65 (0.38), which significantly exceeds the 95% (90%) confidence level, indicating that this model has a more faithful representation for the SST-forced HWs.

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Summer Eurasian Heat Wave and its linkage to SST anomalies over North Atlantic and Barents-Kara Seas

10.5194/egusphere-egu2020-1218 ◽

2020 ◽

Author(s):

Hejing Wang ◽

Dehai Luo

Keyword(s):

Heat Wave ◽

North Atlantic ◽

High Latitude ◽

Heat Waves ◽

Wave Train ◽

Atmospheric Circulation Patterns ◽

The North ◽

Summer Heat ◽

The North Atlantic ◽

Sst Anomalies

In our study, we aim to examine what factors lead to the summer heat waves over Eurasia and their variability. The analysis reveals that the summer heat waves over Eurasia show two kinds of spatial patterns: midlatitude and high latitude types. The mid-latitude heat wave mainly occurred over west Russia in the west of 55&#176;E and in the south of 60&#176;N, whereas the high-latitude type mainly occurred over west Russia in the east of 55&#176;E and in the north of 55&#176;N. We further analyzed the relationship of the two kinds of heat waves with atmospheric circulation patterns in the Atlantic-Eurasian sector and sea surface temperature (SST) anomalies over the North Atlantic and Arctic. The results show that the cold or warm SST anomalies over Barents-Kara Seas (BKS) can significantly influence the latitude and longitude of Russian heat waves, while the heat waves are also related to the latitude of positive SST anomalies over North Atlantic.A mid-latitude wave train propagating into Eurasia and mid-latitude Russian heat waves, which are related to the positive phase of the North Atlantic Oscillation (NAO), are seen when there are strong SST warming in the North Atlantic mid-high latitudes south of 60&#176;N and SST cooling over BKS. In contrast, a high-latitude Russian heat wave can occur over west Russia when there are positive SST anomalies over Baffin Bay, Davis Strait and Labrador Sea north of 60&#176;N and BKS, while this high-latitude wave train is related to the decay of Greenland blocking or the negative NAO phase via high-latitude wave train propagation.

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An ultrastructural study of sertoli cells in two geographically isolated populations of Aphanius dispar

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123143 ◽

1992 ◽

Vol 50 (1) ◽

pp. 548-549

Author(s):

Taber A. Ba-Omar ◽

Philip F. Prentis

Keyword(s):

Ultrastructural Level ◽

Uranyl Acetate ◽

Freshwater Teleost ◽

Isolated Populations ◽

En Bloc ◽

The North ◽

Group A ◽

Ultrathin Sections ◽

Group B ◽

Geographically Isolated

We have recently carried out a study of spermiogenic differentiation in two geographically isolated populations of Aphanius dispar (freshwater teleost), with a view to ascertaining variation at the ultrastructural level. The sampling areas were the Jebel Al Akhdar in the north (Group A) and the Dhofar region (Group B) in the south. Specimens from each group were collected, the testes removed, fixed in Karnovsky solution, post fixed in OsO, en bloc stained with uranyl acetate and then routinely processed to Agar 100 resin, semi and ultrathin sections were prepared for study.

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Urban Heat Islands and Thermal Comfort: A Case Study of Zorrotzaurre Island in Bilbao

Sustainability ◽

10.3390/su13116106 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6106

Author(s):

Irantzu Alvarez ◽

Laura Quesada-Ganuza ◽

Estibaliz Briz ◽

Leire Garmendia

Keyword(s):

Thermal Comfort ◽

Heat Waves ◽

Urban Environments ◽

Urban Heat Islands ◽

Extreme Weather Events ◽

Climate Index ◽

Physiological Equivalent Temperature ◽

Heat Islands ◽

The North ◽

The Impact

This study assesses the impact of a heat wave on the thermal comfort of an unconstructed area: the North Zone of the Island of Zorrotzaurre (Bilbao, Spain). In this study, the impact of urban planning as proposed in the master plan on thermal comfort is modeled using the ENVI-met program. Likewise, the question of whether the urbanistic proposals are designed to create more resilient urban environments is analyzed in the face of increasingly frequent extreme weather events, especially heat waves. The study is centered on the analysis of temperature variables (air temperature and average radiant temperature) as well as wind speed and relative humidity. This was completed with the parameters of thermal comfort, the physiological equivalent temperature (PET) and the Universal Temperature Climate Index (UTCI) for the hours of the maximum and minimum daily temperatures. The results demonstrated the viability of analyzing thermal comfort through simulations with the ENVI-met program in order to analyze the behavior of urban spaces in various climate scenarios.

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Modeling Northern Hemisphere Summer Heat Extreme Changes and Their Uncertainties Using a Physics Ensemble of Climate Sensitivity Experiments

Journal of Climate ◽

10.1175/jcli3877.1 ◽

2006 ◽

Vol 19 (17) ◽

pp. 4418-4435 ◽

Cited By ~ 81

Author(s):

Robin T. Clark ◽

Simon J. Brown ◽

James M. Murphy

Keyword(s):

Structural Changes ◽

Heat Waves ◽

Full Range ◽

Daily Maximum ◽

Model Parameters ◽

Mean Values ◽

Summer Heat ◽

Modeling Uncertainties ◽

Physics Ensemble ◽

Projected Changes

Abstract Changes in extreme daily temperature events are examined using a perturbed physics ensemble of global model simulations under present-day and doubled CO2 climates where ensemble members differ in their representation of various physical processes. Modeling uncertainties are quantified by varying poorly constrained model parameters that control atmospheric processes and feedbacks and analyzing the ensemble spread of simulated changes. In general, uncertainty is up to 50% of projected changes in extreme heat events of the type that occur only once per year. Large changes are seen in distributions of daily maximum temperatures for June, July, and August with significant shifts to warmer conditions. Changes in extremely hot days are shown to be significantly larger than changes in mean values in some regions. The intensity, duration, and frequency of summer heat waves are expected to be substantially greater over all continents. The largest changes are found over Europe, North and South America, and East Asia. Reductions in soil moisture, number of wet days, and nocturnal cooling are identified as significant factors responsible for the changes. Although uncertainty associated with the magnitude of expected changes is large in places, it does not bring into question the sign or nature of the projected changes. Even with the most conservative simulations, hot extreme events are still expected to substantially increase in intensity, duration, and frequency. This ensemble, however, does not represent the full range of uncertainty associated with future projections; for example, the effects of multiple parameter perturbations are neglected, as are the effects of structural changes to the basic nature of the parameterization schemes in the model.

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Heat Events in the Indian Subcontinent under a warming climate scenario: Detection and its Drivers

10.5194/egusphere-egu21-12972 ◽

2021 ◽

Author(s):

Ritika Kapoor ◽

Carmen Alvarez-Castro ◽

Enrico Scoccimarro ◽

Stefano Materia ◽

Silvio Gualdi

Keyword(s):

North Atlantic ◽

Heat Waves ◽

Heat Index ◽

World Population ◽

Western Coast ◽

Positive Correlation ◽

Preliminary Results ◽

The North ◽

The North Atlantic ◽

Heat Events

Rising global temperatures are a potential cause for increase of extreme climate events, such as heat waves, both in severity and frequency. Under an increasing extreme event scenario, the world population of mid- and low-latitude countries is more vulnerable to heat related mortality and morbidity.In India, the events occurred in recent years have made this vulnerability clear, since the numbers of heat-related deaths are on a rise, and heat waves can impact various sectors including health, agriculture, ecosystems and the national economy.Preliminary results show the prevalence of heat events in seven different regions of India during the pre-monsoon (March, April, May) and transitional (May, June, July) months. We consider daily maximum temperatures (Tmax) and the NOAA&#8217;s Heat Index (HI), a combination of temperature and relative humidity that gives an insight into the discomfort because of increment in humidity.We look into various drivers behind the heat events in the seven different clusters, in particular ENSO and the North Atlantic Regimes that have been linked to the generation of heat waves in different parts of India. The preliminary results indicate Nino 3.4 SST anomalies show positive correlation with Tmax anomalies only in the western coast during pre-monsoon season, while in the transitional months positive correlation extends to central and east India. The Tmax composite anomalies for the cold, warm and neutral phases of ENSO show positive anomalies for only warm years and negative anomalies for the cool and neutral years. Heat Index shows similar spatial patterns for correlation analysis and composite anomaly analysis. The Mean Sea Level Pressure (MSLP) composite associated with heat waves (days exceeding 95th percentile=>3 days) show a persistent ridge over the North Atlantic region.&#160;

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More frequent summer heat waves in southwestern China linked to the recent declining of Arctic sea ice

Environmental Research Letters ◽

10.1088/1748-9326/ab8335 ◽

2020 ◽

Vol 15 (7) ◽

pp. 074011

Author(s):

Kaiqiang Deng ◽

Xingwen Jiang ◽

Chundi Hu ◽

Deliang Chen

Keyword(s):

Sea Ice ◽

Heat Waves ◽

Arctic Sea Ice ◽

Southwestern China ◽

Summer Heat ◽

Arctic Sea

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Farmers’ Willingness to Pay for Index-Based Livestock Insurance in the North West of South Africa

Climate ◽

10.3390/cli8030047 ◽

2020 ◽

Vol 8 (3) ◽

pp. 47

Author(s):

Oluwaseun Samuel Oduniyi ◽

Michael Akwasi Antwi ◽

Sibongile Sylvia Tekana

Keyword(s):

South Africa ◽

Willingness To Pay ◽

Heat Waves ◽

Contingent Valuation Method ◽

Sample Selection ◽

Rural Livelihoods ◽

African Countries ◽

Cross Sectional ◽

North West ◽

The North

Rural livelihoods in most developing countries are threatened by climate-related risks such as drought, flood, heat waves, storms, and so on. Although farmers have adopted several adaptation strategies, they have proven less effective than hoped. Hence, index-based livestock insurance, an innovation that significantly assists farmers to acclimatise to climate-related risks, has been proposed; and its adaptability has attracted a notable increase in other African countries. However, the success of its adoption is dependent on the inclination of the farmers to pay for the service. Accordingly, this study investigates their willingness to pay for index-based livestock insurance and its determinants, and the factors influencing the total livestock units to be insured in the North West province of South Africa. Cross-sectional data were obtained from 277 cattle farmers, drawn randomly from the study area. The contingent valuation method was applied to determine the farmers’ willingness to pay; and only 10.8% were willing to pay. Simultaneously, the Heckit sample selection model was used to analyse the data to identify the factors responsible for farmers’ willingness to pay and total livestock units to insure. The findings revealed that farmer’s experience, age, education, marital status, awareness of insurance and household dependents were statistically significant, and influenced the maximum price R600 ($42, max willingness to pay, WTP) of those who accepted index-based livestock insurance. However, by implication, the study concluded that to adopt index-based livestock insurance in the study area among the livestock farmers, there should be policies to cater for the aforementioned factors.

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The Origin of Isolated Populations of the Mountain Weevil, Liparus glabrirostris—The Flagship Species for Riparian Habitats

Journal of Heredity ◽

10.1093/jhered/esaa018 ◽

2020 ◽

Author(s):

Dorota Lachowska-Cierlik ◽

Krzysztof Zając ◽

Miłosz A Mazur ◽

Arkadiusz Sikora ◽

Daniel Kubisz ◽

...

Keyword(s):

Genetic Diversity ◽

Glacial Refugia ◽

Species Range ◽

Flagship Species ◽

Isolated Populations ◽

The Carpathians ◽

The North ◽

Baltic Coast ◽

Riparian Habitats ◽

The Baltic

Abstract Liparus glabrirostris is one of the largest European weevils, and it has been recently proposed as the flagship species for threatened riparian habitats in the mountains. For effective conservation of its populations (and associated habitats), it is crucial to understand its history, contemporary distribution, genetic diversity and predict changes in the range, including its highly isolated populations on the Baltic coast. Here, we examined numerous populations of L. glabrirostris across almost the entire species range using phylogeography and species niche modeling (SNM) approaches. Analyses of mtDNA and nucDNA markers revealed the existence of 2 major mitochondrial lineages generally separated between 1) the Alpine region and 2) the Bohemian Massif, the Carpathians, and the Baltic coast areas. Genetic diversity in nuclear genes was more complicated with no clear division between populations. The origin of Baltic populations was derived from the Carpathians, but there were probably multiple expansion events to the north. SNM suggested the existence of glacial refugia for L. glabrirostris, mainly in the Alps and the Southern Carpathians. Current predictions of species range were found to be generally congruent with zoogeographic data; however, the Baltic coast was not really supported as a suitable area for L. glabrirostris. An important prediction of future distribution (2050–2070 CE) suggests a shrinkage of the L. glabrirostris range and extinction of some of its populations (particularly those isolated on lower altitudes). Based on the aforementioned data, proposals for the protection of this species are proposed, including the designation of several evolutionary units of conservation importance.

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California Central Valley Summer Heat Waves Form Two Ways*

Journal of Climate ◽

10.1175/jcli-d-15-0270.1 ◽

2016 ◽

Vol 29 (3) ◽

pp. 1201-1217 ◽

Cited By ~ 17

Author(s):

Yun-Young Lee ◽

Richard Grotjahn

Keyword(s):

North Pacific ◽

Heat Waves ◽

Central Valley ◽

Maximum Temperature ◽

Northern California ◽

Long Distance ◽

The West ◽

California Coast ◽

The North ◽

The North Pacific

Abstract California Central Valley (CCV) heat waves are grouped into two types based on the temporal and spatial evolution of the large-scale meteorological patterns (LSMPs) prior to onset. The k-means clustering of key features in the anomalous temperature and zonal wind identifies the two groups. Composite analyses show different evolution prior to developing a similar ridge–trough–ridge pattern spanning the North Pacific at the onset of CCV hot spells. Backward trajectories show adiabatic heating of air enhanced by anomalous sinking plus horizontal advection as the main mechanisms to create hot lower-tropospheric air just off the Northern California coast, although the paths differ between clusters. The first cluster develops the ridge at the west coast on the day before onset, consistent with wave activity flux traveling across the North Pacific. Air parcels that arrive at the maximum temperature anomaly (just off the Northern California coast) tend to travel a long distance across the Pacific from the west. The second cluster has the ridge in place for several days prior to extreme CCV heat, but this ridge is located farther north, with heat anomaly over the northwestern United States. This ridge expands south as air parcels at midtropospheric levels descend from the northwest while lower-level parcels over land tend to bring hot air from directions ranging from the hot area to the northeast to the desert areas to the southeast. These two types reveal unexpected dynamical complexity, hint at different remote associations, and expand the assessment needed of climate models’ simulations of these heat waves.

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