Indicators and trend of Walker circulation

Walkerjeva cirkulacija predstavlja eno od tropskih cirkulacij, ki z medsebojno prepletenostjo tvorijo središče tropske konvekcije v območju zahodnega ekvatorialnega Pacifika. Celica Walkerjeve cirkulacije opisuje zonalno-vertikalno cirkulacijo, pri kateri se zrak dviguje nad ekvatorialnim zahodnim Pacifikom, v višji troposferi nad Pacifikom pihajo zahodni vetrovi, nad vzhodnim Pacifikom prevladuje spuščanje, celico pa zaključujejo vzhodni vetrovi v spodnji troposferi od vzhodnega proti zahodnem Pacifiku. V magistrski nalogi bodo predstavljeni možni indikatorji variabilnosti intenzitete Walkerjeve cirkulacije s stališča hitrostnega potenciala in inercijsko-težnostne komponente cirkulacije. Predstavljena bo analiza trenda Walkerjeve cirkulacije pri predpostavki, da je trend predvsem posledica odziva na spremembe v siljenju na območju Indijskega oceana in JV Azije v zadnjih 100 letih. Preučene bodo spremembe v Kelvinovem valu, ki je najznačilnejši val tropske cirkulacije in najbolj intenziven prav na območju zahodnega Pacifika.Walker circulation represents one of the components of tropical circulation which are tightly coupled with each other, producing strong convection centre around the Western equatorial Pacific. The Walker circulation cell describes the zonal-vertical circulation with air rising above equatorial Western Pacific, westerly winds in the upper troposphere above Pacific, sinking air above equatorial Eastern Pacific and easterly winds in the lower troposphere in direction towards Western Pacific. In this master\u27s thesis possible indicators of Walker circulation variability will be presented in terms of velocity potential and inertial-gravity components of flow. The trend analysis of the intensity of Walker circulation will be described assuming the trend as a consequence of differential forcing above Indian ocean and Southeastern Asia in the last century. Changes in Kelvin wave will be studied, due to Kelvin wave being the most significant wave in the tropics

Spatio-Temporal Analysis of the Universal Thermal Climate Index (UTCI) for the Summertime in the Period 2000–2021 in Slovenia: The Implication of Heat Stress for Agricultural Workers

Due to climate change crisis, the risk of occupational heat stress for agricultural workers has recently increased. The temporal and spatial biometeorological conditions in different climatic regions of Slovenia during summer were analyzed using the Universal Thermal Climate Index (UTCI), and additionally the water loss index (SW) and the accepted level of physical activity (MHR). Term values of air temperature, relative air humidity, wind speed at 10 m and cloud cover at 14:00 CEST were used as input for the BioKlima 2.6 software package and were retrieved from the Slovenian Environment Agency for the summer months in the period 2000–2021. The rise in the average UTCI values was shown to be positive and statistically significant for summer (0.7 °C/decade) as well as for all three months, the highest being for June (0.9 °C/decade). The percentage of summer days during 2000–2021 that were under strong or very strong heat stress varied widely by location, ranging from one-third to more than one-half. Average monthly UTCI values at 14:00 CEST were the highest in July, reaching 30 °C in a submediterranean climate, Črnomelj is the only station with this average higher than 32 °C. Daily highest UTCI value was 47 °C (Črnomelj). It was shown that conditions in the middle of a hot summer day are not suitable for moderate or severe agricultural workloads

Spatio-Temporal Analysis of the Universal Thermal Climate Index (UTCI) for the Summertime in the Period 2000–2021 in Slovenia: The Implication of Heat Stress for Agricultural Workers

Due to climate change crisis, the risk of occupational heat stress for agricultural workers has recently increased. The temporal and spatial biometeorological conditions in different climatic regions of Slovenia during summer were analyzed using the Universal Thermal Climate Index (UTCI), and additionally the water loss index (SW) and the accepted level of physical activity (MHR). Term values of air temperature, relative air humidity, wind speed at 10 m and cloud cover at 14:00 CEST were used as input for the BioKlima 2.6 software package and were retrieved from the Slovenian Environment Agency for the summer months in the period 2000–2021. The rise in the average UTCI values was shown to be positive and statistically significant for summer (0.7 °C/decade) as well as for all three months, the highest being for June (0.9 °C/decade). The percentage of summer days during 2000–2021 that were under strong or very strong heat stress varied widely by location, ranging from one-third to more than one-half. Average monthly UTCI values at 14:00 CEST were the highest in July, reaching 30 °C in a submediterranean climate, Črnomelj is the only station with this average higher than 32 °C. Daily highest UTCI value was 47 °C (Črnomelj). It was shown that conditions in the middle of a hot summer day are not suitable for moderate or severe agricultural workloads

Spatio-temporal analysis of the universal thermal climate index (UTCI) for the summertime in the period 2000–2021 in Slovenia

Due to climate change crisis, the risk of occupational heat stress for agricultural workers has recently increased. The temporal and spatial biometeorological conditions in different climatic regions of Slovenia during summer were analyzed using the Universal Thermal Climate Index (UTCI), and additionally the water loss index (SW) and the accepted level of physical activity (MHR). Term values of air temperature, relative air humidity, wind speed at 10 m and cloud cover at 14:00 CEST were used as input for the BioKlima 2.6 software package and were retrieved from the Slovenian Environment Agency for the summer months in the period 20002021. The rise in the average UTCI values was shown to be positive and statistically significant for summer (0.7 °C/decade) as well as for all three months, the highest being for June (0.9 °C/decade). The percentage of summer days during 20002021 that were under strong or very strong heat stress varied widely by location, ranging from one-third to more than one-half. Average monthly UTCI values at 14:00 CEST were the highest in July, reaching 30 °C in a submediterranean climate, Crnomelj is the only station with this average higher than 32 °C. Daily highest UTCI value was 47 °C (Crnomelj). It was shown that conditions in the middle of a hot summer day are not suitable for moderate or severe agricultural workloads

Climate projections of air temperature and precipitation for the Ledava, Pesnica and Vipava basins in the 21st century

V okviru raziskovalnega projekta ‘CeVoTak’, celovito upravljanje malih ukrepov za zadrževanje vode in preprečevanje erozije tal v kmetijskih povodjih, smo naredili oceno spremenjenih temperaturnih in padavinskih razmer do leta 2100. Raziskava je potekala na kmetijskih površinah v povodjih rek Ledave in Pesnice v omiljenem celinskem in reke Vipave v omiljenem sredozemskem podnebju. Za pripravo podnebnih projekcij smo uporabili skupno klimatsko podatkovno bazo - simulacije RCM (Regional Climate Model) iz projekta EURO--CORDEX in scenarije RCP (Representative Concentration Pathway), RCP2.6, 4.5 in 8.5. Projekcije so bile pripravljene za tri obdobja: 1-bližnja prihodnost: 2011–20402-sredina stoletja: 2041–2070 in 3-daljna prihodnost: 2071–2100 za 6 različnih regionalnih podnebnih modelov za povprečne, najnižje in najvišje temperature zraka ter količino padavin. Analiza ansambla modelskih simulacij za vse tri scenarije kaže podobne rezultate za porečje vseh treh rek, in sicer naraščanje temperature (največ pozimi, najmanj spomladi), zanesljivost spremembe je visoka za vse scenarije in obdobja. V primerjavi s temperaturami zraka so projekcije padavinskih razmer manj zanesljive, kažejo pa naraščanje letne količine padavin zaradi dviga pozimi. Uporaba projekcij podnebnih sprememb s strokovno razlago je nujna pri določanju ranljivosti posameznih območij in grajenju odpornosti z uvajanjem ukrepov prilagajanja na podnebne spremembe.As part of the project ‚CeVoTak‘, Integrated Management of Small Water Retention and Soil Erosion Prevention Measures in Agricultural Catchments, we studied changing temperature and precipitation conditions up to the year 2100. The study was conducted on agricultural lands in the catchments of the Ledava and Pesnica rivers in the sub-Pannonian region and the Vipava river in the sub-Mediterranean region. A common climate database was used to create the climate projections - RCM (Regional Climate Model) simulations from the project EURO-CORDEX and scenarios RCP (Representative Concentration Pathway), RCP2.6, 4.5 and 8.5. The projections were prepared for three time periods 2011-20402041-2070 and 2071-2100 for 6 different regional climate models for average, minimum and maximum air temperatures and precipitation. Analysis of the ensemble of model simulations for all scenarios shows similar results for the basin of all rivers, an increase in temperature (maximum in winter, minimum in spring), with high confidence for all scenarios and pe-riods. Projections of precipitation are less reliable, but show an increase in annual precipitation due to the winter increase. The use of climate change projections with expert interpretation is essential for determining the vulnerability of individual areas and building resilience through the implementation of climate change adaptation

Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

The invasive species Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), also known as fall armyworm (FAW), has emerged as a significant threat to agriculture globally, causing considerable economic losses and ecological disruptions. This paper examines the potential risk that FAW poses to Slovenian maize production. Using the maximum entropy algorithm, the climate suitability of Slovenia for FAW as well as for four of its parasitoids is calculated. The data used for the model calculations include species occurrence data, past climate data and regional climate projections for the 21st century. The climate suitability assessments in this study indicate an increasing risk of FAW occurrence in Slovenia in the 21st century, especially in regions with extensive maize cultivation. Projections under different climate change scenarios show that, the likelihood of FAW parasitoids thriving in Slovenia is particularly high, especially for Telenomus remus and Trichogramma pretiosum and overlaps with the regions with the largest areas of maize cultivation. In this context, pre-emptive biological control presents a promising approach. However, consideration of the full impacts associated with the introduction of non-native natural enemies is crucial, highlighting the need for further research and collaboration between stakeholders. Furthermore, this study lays the foundation for evidence-based decision making and emphasises the importance of integrated pest management strategies tailored to the Slovenian agricultural landscape

Frost risk assessment in Slovenia in the period of 1981–2020

As spring frost proves to be an increasing risk throughout Slovenia and Europe, a better assessment of frost risk is needed. The statistical approach presented in this article consists of the conditional probability that the last spring frost occurs before budburst or flowering. The analysis was conducted using two separate phenological models and phenological data of various grapevine (Vitis vinifera L.), apple (Malus domestica), and sweet cherry (Prunus avium L.) varieties in locations across Slovenia. The increase in risk of spring frost for grapevine ranged from 1 to 1980, from 0.06 to 12 for apple, and from 1 to 180 for sweet cherry. Overall, the varieties most prone to frost proved to be Refošk (Teran) and Merlot grapevine varieties as well as the Germersdorf sweet cherry variety. We have identified the location in the hilly region with moderate climate where the Bobovec apple variety is grown as the least exposed to frost. Although counterintuitive, the GDD generally proved somewhat more efficient than the two-phase phenological model BRIN, although not in all cases. For the purpose of the study, the phenological models were calibrated, and the model parameters can serve as invaluable information for further research of this topic

Steps towards comprehensive heat communication in the frame of a heat health warning system in Slovenia

Occupational heat stress has an important negative impact on the well-being, health and productivity of workers and shouldtherefore, be recognized as a public health issue in Europe. There is no comprehensive heat health warning system in Slovenia combining public health measures with meteorological forecasts. The aim of this research was to provide insight into the development of such a system in Slovenia, turning the communication from the current meteoalarm into a broader system that has more information for different social groups. To achieve this goal, the following steps were used: Analysis of summer temperatures and issued meteoalarms, a survey of the general knowledge about heat among the public, organization and management of two stakeholder symposia, and a final survey on workers’ opinions on heat stress and measures, supplemented by interviews with employers. Summer average daily temperature distributions in Slovenia changed during the investigated period (1961–2019) and the mean values increased over time by 2–3 °C. Additionally, the number of days with fulfilled yellow (potentially dangerous) and especially orange (dangerous) meteoalarm conditions increased significantly after 1990. The survey of the general public about heat stress and warnings showed that efforts to raise awareness of heat issues need to be intensified and that public health measures should effectively target vulnerable groups. Stakeholder symposia and further surveys have shown that awareness and understanding of the negative effects of heat stress on health and productivity are still quite low, so effective ways of disseminating information to different sectors while striking the best balance between efficiency, feasibility and economic cost have to be found