Analysis of Extreme Temperature Events in North China Based on EMD Method

2013 ◽  
Vol 295-298 ◽  
pp. 854-858 ◽  
Author(s):  
Xiao Ying Chen ◽  
Yi Min Zhu ◽  
Lin Lin Xia ◽  
Wei Xing Zhang
Keyword(s):  
High Temperature ◽  
Temperature Variation ◽  
North China ◽  
Southern Oscillation ◽  
Extreme Temperature ◽  
Temporal Variations ◽  
Mode Decomposition ◽  
Extreme High Temperature ◽  
Spatio Temporal ◽  
Emd Method

The spatio-temporal variations of extreme temperature in North China during 1954-2008 are analyzed based on Empirical Mode Decomposition (EMD) method. The results show that the interannual-to-interdecadal variabilities of extreme temperature in North China. 3-4 years and 7-8 years interannual variabilities as well as a decreasing trend are dominant while 15 years oscillation takes second place in the extreme low temperature variation. Meanwhile, 3-4 year interannual variabilities are dominant while 6-7 years, 14-15 years 40 years oscillation as well as an increasing trend takes second place in the extreme high temperature variation. 3-4 years interannual variabilities of both extreme low and high temperature are closely related to El Nino-Southern Oscillation (ENSO), while interdecadal variabilities and trend of extreme temperature are obviously associated with the Pacific Decadal Oscillation (PDO). Besides, PDO plays an important role on interdecadal modulation of interannual to decadal variabilities of extreme temperature in North China.

scholarly journals Tropospheric temperature variation over India and links with the Indian summer monsoon : 1971-2000

MAUSAM ◽  
2022 ◽  
Vol 53 (3) ◽  
pp. 289-308
Author(s):  
D. R. KOTHAWALE ◽  
K. RUPA KUMAR
Keyword(s):  
Summer Monsoon ◽  
Southern Oscillation ◽  
Monsoon Season ◽  
Temporal Variations ◽  
Mean Annual Temperature ◽  
Tropospheric Temperature ◽  
Temperature Variations ◽  
Annual Cycles ◽  
The Mean ◽  
Spatio Temporal

In the context of the ever increasing interest in the regional aspects of global warming, understanding the spatio-temporal variations of tropospheric temperature over India is of great importance. The present study, based on the data from 19 well distributed radiosonde stations for the period 1971-2000, examines the seasonal and annual mean temperature variations at the surface and five selected upper levels, viz., 850, 700, 500, 200 and 150 hPa. An attempt has also been made to bring out the association between tropospheric temperature variations over India and the summer monsoon variability, including the role of its major teleconnection parameter, the El Niño/Southern Oscillation (ENSO).   Seasonal and annual mean all-India temperature series are analyzed for surface and five tropospheric levels.  The mean annual cycles of temperature at different tropospheric levels indicate that the pre-monsoon season is slightly warmer than the monsoon season at the surface, 850 hPa and 150 hPa levels, while it is relatively cooler at all intermediate levels.  The mean annual temperature shows a warming of 0.18° C and 0.3° C per 10 years at the surface and 850 hPa, respectively.   Tropospheric temperature anomaly composites of excess (deficient) monsoon rainfall years show pronounced positive (negative) anomalies during the month of May, at all the levels.  The pre-monsoon pressure of Darwin has significant positive correlation with the monsoon temperature at the surface and 850 hPa.

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.

Spatio-temporal variations in cropland phenology in North China over the past 20 years

2010 ◽  
Author(s):  
Mingwei Zhang ◽  
Jinlong Fan ◽  
Guicai Li ◽  
Jian Liu
Keyword(s):  
North China ◽  
Temporal Variations ◽  
The Past ◽  
Spatio Temporal

Analysis of Extreme High-Temperature Time Series Based on Empirical Mode Decomposition

2015 ◽  
Vol 733 ◽  
pp. 914-917
Author(s):  
Hao Ma
Keyword(s):  
Time Series ◽  
High Temperature ◽  
Empirical Mode Decomposition ◽  
Periodic Variation ◽  
Wave Pattern ◽  
Temperature Time Series ◽  
Mode Decomposition ◽  
Extreme High Temperature ◽  
Scale Characteristics ◽  
Temperature Time

In this paper, considering the nonlinear and non-stationary properties of extreme high-temperature time series, we introduce Empirical Mode Decomposition to analyze the extreme high-temperature time series from 1959 to 2012 in Fengxian district of Shanghai. The scale characteristics and oscillating mode characteristics were mainly investigated. The trend of extreme high-temperature also shows periodic variation from decreasing to increasing for the recent fifty years. Analyze the reconstructed modes with the wave pattern: It shows that variability are quite large from 1997 to 1999 and from 1977 to 1982, which shows extreme high-temperature rose and fell dramatically in these periods. The volatility from 2006 to 2008 is far more dramatic than the other times. And it is the most remarkable in the recent fifty years.

scholarly journals The association between extreme temperature and pulmonary tuberculosis in Shandong Province, China, 2005–2016: a mixed method evaluation

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Dongzhen Chen ◽  
Hua Lu ◽  
Shengyang Zhang ◽  
Jia Yin ◽  
Xuena Liu ◽  
...  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Pulmonary Tuberculosis ◽  
Incidence Rate ◽  
Meta Analysis ◽  
Extreme Temperature ◽  
Shandong Province ◽  
Effect Model ◽  
Extreme High Temperature ◽  
The Relationship

Abstract Background The effects of extreme temperature on infectious diseases are complex and far-reaching. There are few studies to access the relationship of pulmonary tuberculosis (PTB) with extreme temperature. The study aimed to identify whether there was association between extreme temperature and the reported morbidity of PTB in Shandong Province, China, from 2005 to 2016. Methods A generalized additive model (GAM) was firstly conducted to evaluate the relationship between daily reported incidence rate of PTB and extreme temperature events in the prefecture-level cities. Then, the effect estimates were pooled using meta-analysis at the provincial level. The fixed-effect model or random-effect model was selected based on the result of heterogeneity test. Results Among the 446,016 PTB reported cases, the majority of reported cases occurred in spring. The higher reported incidence rate areas were located in Liaocheng, Taian, Linyi and Heze. Extreme low temperature had an impact on the reported incidence of PTB in only one prefecture-level city, i.e., Binzhou (RR = 0.903, 95% CI: 0.817–0.999). While, extreme high temperature was found to have a positive effect on reported morbidity of PTB in Binzhou (RR = 0.924, 95% CI: 0.856–0.997) and Weihai (RR = 0.910, 95% CI: 0.843–0.982). Meta-analysis showed that extreme high temperature was associated with a decreased risk of PTB (RR = 0.982, 95% CI: 0.966–0.998). However, extreme low temperature was no relationship with the reported incidence of PTB. Conclusion Our findings are suggested that extreme high temperature has significantly decreased the risk of PTB at the provincial levels. The findings have implications for developing strategies to response to climate change.

scholarly journals North China Plain as a hot spot of ozone pollution exacerbated by extreme high temperatures

2021 ◽  
Author(s):  
Pinya Wang ◽  
Yang Yang ◽  
Huimin Li ◽  
Lei Chen ◽  
Ruijun Dang ◽  
...  
Keyword(s):  
High Temperature ◽  
North China Plain ◽  
North China ◽  
Transport Model ◽  
Hot Spot ◽  
Large Population ◽  
Atmospheric Condition ◽  
Pollutant Emission ◽  
Chemical Production ◽  
Extreme High Temperature

Abstract. A large population in China has been increasingly exposed to both severe ozone (O3) pollution and extreme heat under global warming. Here, the spatiotemporal characteristics of coupled extremes in surface O3 and heat (OPCs) over China are investigated using surface observations, a process-based chemical transport model (GEOS-Chem), and multi-model simulations from Phase 6 of the Coupled Model Intercomparison Project (CMIP6). North China Plain (NCP, 37–41° N; 114–120° E) is identified as a hot spot of OPCs, where more than half of the O3 pollution days are accompanied by high temperature extremes. OPCs over NCP exceed 40 days during 2014–2019, exhibiting an increasing trend. Both O3 concentrations and temperatures are elevated during OPCs compared to O3 pollution days occurring individually (OPIs). Therefore, OPCs impose more severe health impacts to human than OPIs, but the stronger health effects are mainly driven by the higher temperatures. GEOS-Chem simulations further reveal that enhanced chemical production resulting from hot and stable atmospheric condition under anomalous weather pattern primarily contributes to the exacerbated O3 levels during OPCs. In the future, CMIP6 projections suggest increased occurrences of OPCs over NCP in the middle of this century, but by the end of this century, OPCs may decrease or increase depending on the pollutant emission scenarios. However, for all future scenarios, extreme high temperature will play an increasingly important role in modulating O3 pollution in a warming climate.

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