Theoretical Analysis of Sintering Process Relevant to the Maximum Temperature and the Propagation Speed of Heat Wave

Abstract. The purpose of this article is to show the extreme temperature regime of heat waves across Africa over recent years (1981–2015). Heat waves have been quantified using the Heat Wave Magnitude Index daily (HWMId), which merges the duration and the intensity of extreme temperature events into a single numerical index. The HWMId enables a comparison between heat waves with different timing and location, and it has been applied to maximum and minimum temperature records. The time series used in this study have been derived from (1) observations from the Global Summary of the Day (GSOD) and (2) reanalysis data from ERA-Interim. The analysis shows an increasing number of heat waves of both maxima and minima temperatures in the last decades. Results from heat wave analysis of maximum temperature (HWMIdtx) indicate an increase in intensity and frequency of extreme events. Specifically, from 1996 onwards it is possible to observe HWMIdtx spread with the maximum presence during 2006–2015. Between 2006 and 2015 the frequency (spatial coverage) of extreme heat waves had increased to 24.5 observations per year (60.1 % of land cover), as compared to 12.3 per year (37.3 % of land area) in the period from 1981 to 2005 for GSOD stations (reanalysis).

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Analysis of the extreme heat events in Iran

International Journal of Climate Change Strategies and Management ◽

10.1108/ijccsm-04-2016-0046 ◽

2017 ◽

Vol 9 (4) ◽

pp. 418-432 ◽

Cited By ~ 1

Author(s):

Hojjatollah Yazdanpanah ◽

Josef Eitzinger ◽

Marina Baldi

Keyword(s):

Trend Analysis ◽

Heat Wave ◽

Heat Waves ◽

Temporal Variations ◽

Maximum Temperature ◽

Daily Maximum Temperature ◽

Daily Maximum ◽

Positive Trend ◽

Content Type ◽

Hot Days

Purpose The purpose of this paper is to assess the spatial and temporal variations of extreme hot days (H*) and heat wave frequencies across Iran. Design/methodology/approach The authors used daily maximum temperature (Tmax) data of 27 synoptic stations in Iran. These data were standardized using the mean and the standard deviation of each day of the year. An extreme hot day was defined when the Z score of daily maximum temperature of that day was equal or more than a given threshold fixed at 1.7, while a heat wave event was considered to occur when the Z score exceeds the threshold for at least three continuous days. According to these criteria, the annual frequency of extreme hot days and the number of heat waves were determined for all stations. Findings The trend analysis of H* shows a positive trend during the past two decades in Iran, with the maximum number of H* (110 cases) observed in 2010. A significant trend of the number of heat waves per year was also detected during 1991-2013 in all the stations. Overall, results indicate that Iran has experienced heat waves in recent years more often than its long-term average. There will be more frequent and intense hot days and heat waves across Iran until 2050, due to estimated increase of mean air temperature between 0.5-1.1 and 0.8-1.6 degree centigrade for Rcp2.6 and Rcp8.8 scenarios, respectively. Originality/value The trend analysis of hot days and heat wave frequencies is a particularly original aspect of this paper. It is very important for policy- and decision-makers especially in agriculture and health sectors of Iran to make some adaptation strategies for future frequent and intense hot days over Iran.

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Immobilisation process for contaminated zeolitic ion exchangers from Fukushima

MRS Advances ◽

10.1557/adv.2017.194 ◽

2016 ◽

Vol 1 (62) ◽

pp. 4089-4094 ◽

Cited By ~ 1

Author(s):

D. Pletser ◽

R. K. Chinnam ◽

M. Kamoshida ◽

W.E. Lee

Keyword(s):

Composite Material ◽

Thermal Treatment ◽

Low Temperature ◽

Glass Composition ◽

Glass Frit ◽

Maximum Temperature ◽

Sintering Process ◽

Volatile Species ◽

Glass Composite ◽

Fukushima Daiichi

AbstractThe clean-up of the Fukushima Daiichi site, after the March 2011 earthquake and tsunami, continues to generate large amounts of spent adsorbents. These adsorbents need to be disposed of permanently in a low temperature immobilisation process to avoid volatilising radioactive Cs and Sr species. To this end an immobilisation process with a maximum temperature of 600 °C was developed by sintering model waste with glass frit to form a dense Glass Composite Material (GCM) wasteform. A zeolitic model wasteform, chabazite, was sintered with a lead borosilicate glass composition at a maximum temperature of 600 °C. The sintering process was optimised with various thermal treatment steps to ensure that volatile species, aqueous or otherwise, were released before full sintering to yield a dense final wasteform. With this process dense wasteforms of up to 40 wt. % chabazite have been achieved.

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A Stepwise-Clustered Simulation Approach for Projecting Future Heat Wave Over Guangdong Province

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.761251 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jiayan Ren ◽

Guohe Huang ◽

Yongping Li ◽

Xiong Zhou ◽

Jinliang Xu ◽

...

Keyword(s):

Heat Wave ◽

Climate Models ◽

Extreme Event ◽

Heat Waves ◽

Extreme Temperature ◽

Global Climate Models ◽

Maximum Temperature ◽

Daily Maximum Temperature ◽

Daily Maximum ◽

Simulation Approach

A heat wave is an important meteorological extreme event related to global warming, but little is known about the characteristics of future heat waves in Guangdong. Therefore, a stepwise-clustered simulation approach driven by multiple global climate models (i.e., GCMs) is developed for projecting future heat waves over Guangdong under two representative concentration pathways (RCPs). The temporal-spatial variations of four indicators (i.e., intensity, total intensity, frequency, and the longest duration) of projected heat waves, as well as the potential changes in daily maximum temperature (i.e., Tmax) for future (i.e., 2006–2095) and historical (i.e., 1976–2005) periods, were analyzed over Guangdong. The results indicated that Guangdong would endure a notable increasing annual trend in the projected Tmax (i.e., 0.016–0.03°C per year under RCP4.5 and 0.027–0.057°C per year under RCP8.5). Evaluations of the multiple GCMs and their ensemble suggested that the developed approach performed well, and the model ensemble was superior to any single GCM in capturing the features of heat waves. The spatial patterns and interannual trends displayed that Guangdong would undergo serious heat waves in the future. The variations of intensity, total intensity, frequency, and the longest duration of heat wave are likely to exceed 5.4°C per event, 24°C, 25 days, and 4 days in the 2080s under RCP8.5, respectively. Higher variation of those would concentrate in eastern and southwestern Guangdong. It also presented that severe heat waves with stronger intensity, higher frequency, and longer duration would have significant increasing tendencies over all Guangdong, which are expected to increase at a rate of 0.14, 0.83, and 0.21% per year under RCP8.5, respectively. Over 60% of Guangdong would suffer the moderate variation of heat waves to the end of this century under RCP8.5. The findings can provide decision makers with useful information to help mitigate the potential impacts of heat waves on pivotal regions as well as ecosystems that are sensitive to extreme temperature.

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A Consistent Methodology to Evaluate Temperature and Heat Wave Future Projections for Cities: A Case Study for Lisbon

Applied Sciences ◽

10.3390/app10031149 ◽

2020 ◽

Vol 10 (3) ◽

pp. 1149 ◽

Cited By ~ 1

Author(s):

Alfredo Rocha ◽

Susana C. Pereira ◽

Carolina Viceto ◽

Rui Silva ◽

Jorge Neto ◽

...

Keyword(s):

Climate Change ◽

Heat Wave ◽

Heat Waves ◽

Maximum Temperature ◽

Present Climate ◽

Average Maximum ◽

Recent Climate ◽

Average Maximum Temperature ◽

Accumulated Temperature

Heat waves are large-scale atmospheric phenomena that may cause heat stress in ecosystems and socio-economic activities. In cities, morbidity and mortality may increase during a heat wave, overloading health and emergency services. In the face of climate change and associated warming, cities need to adapt and mitigate the effects of heat waves. This study suggests a new method to evaluate heat waves’ impacts on cities by considering some aspects of heat waves that are not usually considered in other similar studies. The method devises heat wave quantities that are easy to calculate; it is relevant to assessing their impacts and permits the development of adaptation measures. This study applies the suggested method to quantify various aspects of heat waves in Lisbon for future climate projections considering future mid-term (2046–2065) and long-term (2081–2100) climates under the RCP8.5 greenhouse emission scenario. This is achieved through the analysis of various regional climate simulations performed with the WRF model and an ensemble of EURO-CORDEX models. This allows an estimation of uncertainty and confidence of the projections. To evaluate the climate change properties of heat waves, statistics for future climates are compared to those for a reference recent climate. Simulated temperatures are first bias corrected to minimize the model systematic errors relative to observations. The temperature for mid and long-term futures is expected to increase relative to the present by 1.6 °C and 3.6 °C, respectively, with late summer months registering the highest increases. The number of heat wave days per year will increase on average from 10, in the present climate, to 38 and 63 in mid and long-term climates, respectively. Heat wave duration, intensity, average maximum temperature, and accumulated temperature during a heat wave will also increase. Heat waves account for an annual average of accumulated temperature of 358 °C·day in the present climate, while in the mid and long-term, future climates account for 1270 °C·day and 2078 °C·day, respectively. The largest increases are expected to occur from July to October. Extreme intensity and long-duration heat waves with an average maximum temperature of more than 40 °C are expected to occur in the future climates.

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Model evaluation for Heatwaves over South Korea in CMIP6 models

10.5194/egusphere-egu2020-12919 ◽

2020 ◽

Author(s):

Ji-Seon Oh ◽

Maeng-Ki Kim ◽

Dae-Geun Yu ◽

Jeong Sang

Keyword(s):

Heat Wave ◽

Development Program ◽

Maximum Temperature ◽

Daily Maximum Temperature ◽

Daily Maximum ◽

Northwestern Pacific ◽

Circulation Index ◽

Convective Activity ◽

Simulation Performance ◽

Diagnostic Indices

In this study, we defined diagnostic indices to evaluate the CMIP6 models based on the heatwaves mechanisms of Korea presented in previous studies. Based on this, the simulation performance of the model was quantitatively evaluated using Relative Error (RE), Inter-annual Variability Skill-score (IVS), and Correlation Coefficient (CC). The REs in diagnostic indices are still large, especially in heat wave circulation index (HWCI) and Indian summer monsoon rainfall index (IMRI), which is mainly due to weak convective activity bias over the northwestern Pacific Ocean and the northwestern India. However, the IVSs in diagnostic indices have been improved overall in the CMIP6 compared to the CMIP5, especially in the IMRI. The CC between the daily maximum temperature (TMAX) and the diagnostic factors in the model is very higher in HWCI than other indices, indicating that the convective activity over the northwestern Pacific is very important in heat wave in Korea. As a result, the total ranking of the model performance for heatwaves in Korea suggested that EC-Earth3-Veg, EC-Earth3, and UKESM-1-0-LL ranked high in CMIP6.&#160;This work was funded by the Korea Meteorological Administration Research and Development Program under Grant KMI(KMI2018-03410)

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Database of major European heat waves from 1950 to present

10.5194/egusphere-egu2020-2973 ◽

2020 ◽

Author(s):

Ondřej Lhotka ◽

Jan Kyselý

Keyword(s):

Surface Energy ◽

Heat Wave ◽

Spatial Patterns ◽

Climate Models ◽

Heat Waves ◽

Surface Energy Budget ◽

Maximum Temperature ◽

Daily Maximum Temperature ◽

Human Society ◽

Driving Mechanisms

Europe experienced several major heat waves in the recent summers, substantially affecting human society and environment. Heat waves are generally related to joint effect of perturbed atmospheric circulation and anomalies in surface energy budget, and they are often linked to hydrological preconditioning. Contributions of these driving mechanisms, however, vary across European climatic zones. Climate models struggle to simulate the spatial differences properly, ultimately leading to large uncertainties in future heat waves&#8217; characteristics. As the first step towards identifying spatial patterns of differences between driving mechanisms of temperature extremes, a pan-European database of observed major heat waves has been created. Heat waves are studied using the E-OBS 20.0e dataset in 0.1&#176; horizontal grid spacing, which is analogous to that used in the ERA5 reanalysis and CORDEX regional climate models. Magnitude of heat waves is defined with respect to local daily maximum temperature (Tmax) variance, using multiples of standard deviation of Tmax summed across individual events. For each heat wave, circulation conditions and surface energy fluxes are analysed using the ERA5 reanalysis, in order to study their links to the heat wave magnitude and geographical location. In the next step, these findings are used for analyzing spatial patterns of heat wave mechanisms and as a source of reference data for evaluation of relevant processes in climate models.

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Study on the Influence of Heat Wave and Cold Wave Characteristics and Vulnerable Areas in Busan, Ulsan and Gyeongsangnam-do

10.5194/egusphere-egu2020-7045 ◽

2020 ◽

Author(s):

Miyeong Jo ◽

Jiyeun Ye ◽

Jihye Yun ◽

Jaeeun You ◽

Juyeong Kim ◽

...

Keyword(s):

Heat Wave ◽

Heat Waves ◽

Weather Conditions ◽

Cold Weather ◽

Current Status ◽

Maximum Temperature ◽

Cold Wave ◽

Observation Data ◽

Physical Damage ◽

Wave Impact

The frequency of extreme weather phenomena such as heat wave and cold wave has increased recently, and the intensity of weather has been strengthened, resulting in human and physical damage. The Republic of Korea has been working to reduce damage since 2018 by including heat and cold waves in natural disasters. The Korea Meteorological Administration (KMA) also provides impact-based forecasts, which requires research that suits local characteristics. In this study, weather observation data related to the summer heat wave in Busan, Ulsan and South Gyeongsang Province was analyzed to determine the weather conditions for the heat wave. In addition, in relation to the heat wave impact-based forecast that was provided regularly in 2019, the heat threshold was applied by comparing the current status of the heat-related patients with the maximum temperature, the number of consecutive days of the heat wave and the current status of the heat-related patients. The impacts of heat waves in different fields were analyzed, including livestock waste, fisheries food damage, and heat damage by crops. The cold wave also analyzed the number of days of cold wave in Busan, Ulsan, and South Gyeongsang Province by comparing the lowest temperature with the current status of cold-related patients. The impacts of cold weather conditions such as wind direction, wind speed and the number of consecutive days of the cold wave were also analyzed. Further, for regular provision of cold wave impact-based forecast to be implemented in 2020, the impacts of each cold wave vulnerable areas suitable for Busan, Ulsan, and South Gyeongsang Province were analyzed and referred to when applying cold wave thresholds.

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Neonates in Ahmedabad, India, during the 2010 Heat Wave: A Climate Change Adaptation Study

Journal of Environmental and Public Health ◽

10.1155/2014/946875 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 10

Author(s):

Khyati Kakkad ◽

Michelle L. Barzaga ◽

Sylvan Wallenstein ◽

Gulrez Shah Azhar ◽

Perry E. Sheffield

Keyword(s):

Climate Change ◽

Heat Wave ◽

Climate Change Adaptation ◽

Vulnerable Populations ◽

Urban Areas ◽

Neonatal Morbidity ◽

Maximum Temperature ◽

Daily Maximum Temperature ◽

Daily Maximum ◽

Maternity Ward

Health effects from climate change are an international concern with urban areas at particular risk due to urban heat island effects. The burden of disease on vulnerable populations in non-climate-controlled settings has not been well studied. This study compared neonatal morbidity in a non-air-conditioned hospital during the 2010 heat wave in Ahmedabad to morbidity in the prior and subsequent years. The outcome of interest was neonatal intensive care unit (NICU) admissions for heat. During the months of April, May, and June of 2010, 24 NICU admissions were for heat versus 8 and 4 in 2009 and 2011, respectively. Both the effect of moving the maternity ward and the effect of high temperatures were statistically significant, controlling for each other. Above 42 degrees Celsius, each daily maximum temperature increase of a degree was associated with 43% increase in heat-related admissions (95% CI 9.2–88%). Lower floor location of the maternity ward within hospital which occurred after the 2010 heat wave showed a protective effect. These findings demonstrate the importance of simple surveillance measures in motivating a hospital policy change for climate change adaptation—here relocating one ward—and the potential increasing health burden of heat in non-climate-controlled institutions on vulnerable populations.

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