Recent observed changes in extreme high‐temperature events and associated meteorological conditions over Africa

2021 ◽  
Author(s):  
Vedaste Iyakaremye ◽  
Gang Zeng ◽  
Irfan Ullah ◽  
Aimable Gahigi ◽  
Richard Mumo ◽  
...  
Keyword(s):  
High Temperature ◽  
Meteorological Conditions ◽  
Extreme High Temperature

Host choice, settling and folding leaf behaviors of the larval rice leaf folder under heat stress

2016 ◽  
Vol 106 (6) ◽  
pp. 809-817 ◽  
Author(s):  
M.A. Bodlah ◽  
A.-X. Zhu ◽  
X.-D. Liu
Keyword(s):  
Heat Stress ◽  
High Temperature ◽  
Host Choice ◽  
Cnaphalocrocis Medinalis ◽  
Behavioral Traits ◽  
The Third ◽  
Rice Leaf ◽  
Rice Leaf Folder ◽  
Extreme High Temperature ◽  
Third Instar Larvae

AbstractExtreme high-temperature events are the key factor to determine population dynamics of the rice leaf folder,Cnaphalocrocis medinalis(Guenée), in summer. Although we know that adult of this insect can migrate to avoid heat stress, the behavioral response of larva to high temperature is still unclear. Therefore, impacts of high temperature on behavioral traits ofC. medinalisincluding host choice, settling and folding leaf were observed. The results revealed that these behavioral traits were clearly influenced by high temperature. The larvae preferred maize leaves rather than rice and wheat at normal temperature of 27°C, but larvae experienced a higher temperature of 37 or 40°C for 4 h preferred rice leaves rather than maize and wheat. Capacity of young larvae to find host leaves or settle on the upper surface of leaves significantly reduced when they were treated by high temperature. High temperature of 40°C reduced the leaf-folding capacity of the third instar larvae, but no effects were observed on the fourth and fifth instar larvae. Short-term heat acclimation could not improve the capacity of the third instar larvae to make leaf fold under 40°C.

Different responses of scleractinian coral Acropora pruinosa from Weizhou Island during extreme high temperature events

Coral Reefs ◽  
2021 ◽  
Author(s):  
Xiaopeng Yu ◽  
Kefu Yu ◽  
Biao Chen ◽  
Zhiheng Liao ◽  
Jiayuan Liang ◽  
...  
Keyword(s):  
High Temperature ◽  
Scleractinian Coral ◽  
Extreme High Temperature

scholarly journals Comparison of Atmospheric Circulation Anomalies between Dry and Wet Extreme High-Temperature Days in the Middle and Lower Reaches of the Yellow River

Atmosphere ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1265
Author(s):  
Hangcheng Ge ◽  
Gang Zeng ◽  
Vedaste Iyakaremye ◽  
Xiaoye Yang ◽  
Zongming Wang
Keyword(s):  
High Temperature ◽  
Atmospheric Circulation ◽  
Yellow River ◽  
Wave Train ◽  
The Yellow River ◽  
South Asian High ◽  
Opposite Pattern ◽  
Extreme High Temperature ◽  
Circulation Anomalies ◽  
Atmospheric Circulation Anomalies

Many previous studies have reported that atmospheric circulation anomalies are generally the direct cause of extreme high-temperature (EHT). However, the atmospheric circulation anomalies of EHT days with different humidity and the differences between them are less often discussed, while humidity plays an important role in how people feel in a high-temperature environment. Therefore, this study uses 1961–2016 CN05.1 daily observational data and NCEP/NCAR reanalysis data to classify summer EHT days in China into dry and wet. Furthermore, we investigate the atmospheric circulation anomalies associated with the dry and wet EHT days in the middle and lower reaches of the Yellow River (MLRYR). The results reveal that dry EHT days are likely to be caused by adiabatic heating from anomalous subsidence, while wet EHT days are more likely caused by the low-latitude water vapor and heat anomalies brought by the Western Pacific Subtropical High (WPSH). This may be due to a remarkable westward/southward/narrowed extension of the Continental High (CH)/WPSH/South Asian High (SAH) accompanied by an occurrence of dry EHT day. The opposite pattern is observed for wet EHT days. Moreover, a wave train like the Silk Road pattern from the midlatitudes could affect the dry EHT days, while wet EHT days are more likely to be affected by a wave train from high latitudes. Knowing the specific characteristics of dry and wet EHT days and their associated atmospheric circulations could offer new insights into disaster risk prevention and reduction.

scholarly journals Extreme High‐Temperature Events Over East Asia in 1.5°C and 2°C Warmer Futures: Analysis of NCAR CESM Low‐Warming Experiments

2018 ◽  
Vol 45 (3) ◽  
pp. 1541-1550 ◽  
Author(s):  
Donghuan Li ◽  
Tianjun Zhou ◽  
Liwei Zou ◽  
Wenxia Zhang ◽  
Lixia Zhang
Keyword(s):  
High Temperature ◽  
East Asia ◽  
Extreme High Temperature

scholarly journals Spatial Assessment of Heat Exposure in Bay Cities: A Case of Xiamen in China

2018 ◽  
Vol 53 ◽  
pp. 03065
Author(s):  
Haifeng Yang ◽  
Ya'nan Wang ◽  
Wei Shui
Keyword(s):  
High Temperature ◽  
Index System ◽  
Heat Exposure ◽  
Spatial Differentiation ◽  
Evaluation Index System ◽  
Theoretical Development ◽  
Evaluation Index ◽  
Rapid Urbanization ◽  
Extreme High Temperature ◽  
Exposure Evaluation

With the global warming, the rapid urbanization process and the increasing intensity and scope of human activities, extreme high temperature and cooresponding high temperature events were frequent, meanwhile, the degree of urban exposure to high temperatures was growing. The research constructed the heat exposure evaluation index system by taking the heat exposure evaluation index system in Xiamen, a gulf-based city with high-temperature. This study evaluated the influence factors, spatial differentiation features and hotspots of the heat exposure based on the methods of geo-spatial analysis, emergy accounting theory, expert consultation and analytic hierarchy process in Xiamen. The research results were expected to promote the theoretical development of urban heat exposure researches, and to provide decision-making reference for heat exposure assessment, regulation and adaptation in Xiamen and similar high temperature cities.

scholarly journals Experimental Study of the Temperature Distribution in CRTS-II Ballastless Tracks on a High-Speed Railway Bridge

2020 ◽  
Vol 10 (6) ◽  
pp. 1980 ◽  
Author(s):  
Lei Zhao ◽  
Ling-Yu Zhou ◽  
Guang-Chao Zhang ◽  
Tian-Yu Wei ◽  
Akim D. Mahunon ◽  
...  
Keyword(s):  
High Temperature ◽  
Temperature Distribution ◽  
Temperature Gradient ◽  
High Speed ◽  
Railway Track ◽  
Vertical Temperature ◽  
High Speed Railway ◽  
Extreme High Temperature ◽  
Transverse Temperature ◽  
Temperature Test

To study the temperature distribution in the China Railway Track System Type II ballastless slab track on a high-speed railway (HSR) bridge, a 1:4 scaled specimen of a simply-supported concrete box girder bridge with a ballastless track was constructed in laboratory. Through a rapid, extreme high temperature test in winter and a conventional high temperature test in summer, the temperature distribution laws in the track on the HSR bridge were studied, and the vertical and transverse temperature distribution trend was suggested for the track. Firstly, the extreme high temperature test results showed that the vertical temperature and the vertical temperature difference distribution in the track on HSR bridge were all nonlinear with three stages. Secondly, the extreme high temperature test showed that the transverse temperature distribution in the track was of quadratic parabolic nonlinear form, and the transverse temperature gradient in the bottom base was significantly higher than that of the other layers of the track. Thirdly, the three-dimensional temperature distribution in the track on HSR bridge was a nonlinear, three-stage surface. Furthermore, similar regularities were also obtained in the conventional high temperature test, in which the temperature span ranges were different from those of the extreme high temperature test. In addition, the conventional high temperature test also showed that under the natural environment conditions, the internal temperature gradient in the track layers changed periodically (over a period of 24 h).

scholarly journals Optimization of SAW Devices with LGS/Pt Structure for Sensing Temperature

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2441
Author(s):  
Xueling Li ◽  
Wen Wang ◽  
Shuyao Fan ◽  
Yining Yin ◽  
Yana Jia ◽  
...  
Keyword(s):  
High Temperature ◽  
Quality Factor ◽  
Short Pulse ◽  
Extreme Temperature ◽  
Parameters Optimization ◽  
Design Parameters ◽  
Q Value ◽  
Element Analysis ◽  
Saw Devices ◽  
Extreme High Temperature

Research has shown that SAW (surface acoustic wave) devices with an LGS/Pt (langasite La3Ga5SiO14/platinum) structure are useful in high-temperature sensor applications. Extreme high temperature brings great acoustic attenuation because of the thermal radiation loss, which requires that the sensing device offer a sufficiently high quality factor (Q) and a low loss. Therefore, it is necessary to improve the performance of the quality factor as much as possible so as to better meet the application of high-temperature sensors. Based on these reasons, the main work of this paper was to extract accurate simulation parameters to optimize the Pt/LGS device and obtain Q-value device parameters. Optimization of SAW devices with LGS/Pt structure for sensing extreme high temperature was addressed by employing a typical coupling of modes (COM) model in this work. Using the short pulse method, the reflection coefficient of Pt electrodes on LGS substrate was extracted accurately by characterizing the prepared SAW device with strategic design. Other relevant parameters for COM simulation were determined by finite element analysis. To determine the optimal design parameters, the COM simulation was conducted on the SAW sensing device with a one-port resonator pattern for sensing extreme temperature, which allows for a larger Q-value and low insertion loss. Experimental results validate the theoretical simulation. In addition, the corresponding high-temperature characteristics of the prepared sensing device were investigated.

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