scholarly journals Variation characteristics of extreme temperature in Yunnan province and Guizhou province

2021 ◽  
Vol 257 ◽  
pp. 03007
Author(s):  
Li Xirong ◽  
Yang Dong ◽  
Yi Wei
Keyword(s):  
Yunnan Province ◽  
Extreme Temperature ◽  
Daily Basis ◽  
Guizhou Province ◽  
Maximum Temperature ◽  
Cold Night ◽  
Temperature Index ◽  
Abrupt Changes ◽  
Variation Characteristics ◽  
Temporal And Spatial Characteristics

Using the daily temperature data from meteorological stations in Yunnan province and Guizhou province and Guizhou province from 2000 to 2019, NCEP/NCAR re-analyzed the data on a daily basis, and analyzed the temporal and spatial characteristics of extreme temperature events in the study area. Research shows that the extreme temperature in Yunnan province and Guizhou province region is warming; the extreme temperature index is different in spatial tendency, and all have abrupt changes; the maximum monthly maximum temperature and the heat persistence index will continue to increase in the future, the number of cold night days and the cold persistence index are on a strong and continuous decreasing trend.

scholarly journals Change in mean and extreme temperature at Yingkou station in Northeast China from 1904 to 2017

2021 ◽  
Vol 164 (3-4) ◽  
Author(s):  
Xiaoying Xue ◽  
Guoyu Ren ◽  
Xiubao Sun ◽  
Panfeng Zhang ◽  
Yuyu Ren ◽  
...  
Keyword(s):  
Northeast China ◽  
Extreme Temperature ◽  
Maximum Temperature ◽  
Data Set ◽  
The Past ◽  
Significant Downward Trend ◽  
Cold Events ◽  
Temperature Indices ◽  
Increasing Trends ◽  
Change In Mean

AbstractThe understanding of centennial trends of extreme temperature has been impeded due to the lack of early-year observations. In this paper, we collect and digitize the daily temperature data set of Northeast China Yingkou meteorological station since 1904. After quality control and homogenization, we analyze the changes of mean and extreme temperature in the past 114 years. The results show that mean temperature (Tmean), maximum temperature (Tmax), and minimum temperature (Tmin) all have increasing trends during 1904–2017. The increase of Tmin is the most obvious with the rate of 0.34 °C/decade. The most significant warming occurs in spring and winter with the rate of Tmean reaching 0.32 °C/decade and 0.31 °C/decade, respectively. Most of the extreme temperature indices as defined using absolute and relative thresholds of Tmax and Tmin also show significant changes, with cold events witnessing a more significant downward trend. The change is similar to that reported for global land and China for the past six decades. It is also found that the extreme highest temperature (1958) and lowest temperature (1920) records all occurred in the first half of the whole period, and the change of extreme temperature indices before 1950 is different from that of the recent decades, in particular for diurnal temperature range (DTR), which shows an opposite trend in the two time periods.

scholarly journals Assessment of Seasonal Variability of Extreme Temperature in Mainland China under Climate Change

2021 ◽  
Vol 13 (22) ◽  
pp. 12462
Author(s):  
Wei-Xiong Yan ◽  
Jun-Fang Zhao ◽  
Jian-Ping Li ◽  
Yun-Xia Wang
Keyword(s):  
Annual Cycle ◽  
Seasonal Cycle ◽  
Mainland China ◽  
Extreme Temperature ◽  
Spatial Characteristic ◽  
Maximum Temperature ◽  
Positive Trend ◽  
Extreme Temperatures ◽  
Annual Average ◽  
Temperature Seasonality

Some studies have suggested that variations in the seasonal cycle of temperature and season onset could affect the efficiency in the use of radiation by plants, which would then affect yield. However, the study of the temporal variation in extreme climatic variables is not sufficient in China. Using seasonal trend analysis (STA), this article evaluates the distribution of extreme temperature seasonality trends in mainland China, describes the trends in the seasonal cycle, and detects changes in extreme temperature characterized by the number of hot days (HD) and frost days (FD), the frequency of warm days (TX90p), cold days (TX10p), warm nights (TN90p), and cold nights (TN10p). The results show a statistically significant positive trend in the annual average amplitudes of extreme temperatures. The amplitude and phase of the annual cycle experience less variation than that of the annual average amplitude for extreme temperatures. The phase of the annual cycle in maximum temperature mainly shows a significant negative trend, accounting for approximately 30% of the total area of China, which is distributed across the regions except for northeast and southwest. The amplitude of the annual cycle indicates that the minimum temperature underwent slightly greater variation than the maximum temperature, and its distribution has a spatial characteristic that is almost bounded by the 400 mm isohyet, increasing in the northwest and decreasing in the southeast. In terms of the extreme air temperature indices, HD, TX90p, and TN90p show an increasing trend, FD, TX10p, and TN10p show a decreasing trend. They are statistically significant (p < 0.05). This number of days also suggests that temperature has increased over mainland China in the past 42 years.

scholarly journals Heat waves in Africa 1981–2015, observations and reanalysis

2017 ◽  
Vol 17 (1) ◽  
pp. 115-125 ◽  
Author(s):  
Guido Ceccherini ◽  
Simone Russo ◽  
Iban Ameztoy ◽  
Andrea Francesco Marchese ◽  
Cesar Carmona-Moreno
Keyword(s):  
Heat Wave ◽  
Heat Waves ◽  
Extreme Temperature ◽  
Reanalysis Data ◽  
Maximum Temperature ◽  
Wave Analysis ◽  
Land Area ◽  
Spatial Coverage ◽  
Temperature Records ◽  
Numerical Index

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).

scholarly journals Analysis of changes in daily temperature and precipitation extreme in Jakarta on period of 1986-2014

2018 ◽  
Vol 229 ◽  
pp. 02017
Author(s):  
Aulia N. Khoir ◽  
R. Mamlu’atur ◽  
Agus Safril ◽  
Akhmad Fadholi
Keyword(s):  
Climate Change ◽  
Maximum Temperature ◽  
Temperature Index ◽  
Extreme Climate ◽  
Rainfall Index ◽  
Temperature And Precipitation ◽  
Precipitation Characteristics ◽  
Expert Team ◽  
Weather Stations ◽  
Climate Events

Climate change due to an increase in greenhouse gas concentrations has led to changes in extreme climate events. IPCC 2007 already predicted that average global temperatures would reach 0.74⁰ C in the last 100 years (1906-2005). A study on the temperature index trends and extreme precipitation in the period of 1986-2014 in Jakarta are represented by 5 weather stations. Daily of maximum temperature, minimum temperature, and precipitation data are calculated using RClimDex Software so that temperature and rainfall index data are obtained. The indexes are extreme climate indexes defined by ETCCDMI (Expert Team for Climate Change Detection Monitoring and Indices). The indexes consist of TN10p, TN90p, TX10p, TX90p, TNn, TNx, TXn, TXx, DTR, RX1day, RX5day, RCPTOT, CDD, CWD, and R95p. The purpose of this research is to know the change of temperature and precipitation characteristics from observation result in Jakarta by using index calculation. The results show that Jakarta has number of hot days according to the trends which are generally increasing. It can cause the temperature in Jakarta to get hotter. However, for the rainfall, the upward or downward trend is not significant, so it can be said there is no change in precipitation in Jakarta during 1986-2014.

scholarly journals Effects of Urbanization on Regional Extreme-Temperature Changes in China, 1960–2016

2020 ◽  
Vol 12 (16) ◽  
pp. 6560 ◽  
Author(s):  
Junliang Qiu ◽  
Xiankun Yang ◽  
Bowen Cao ◽  
Zhilong Chen ◽  
Yuxuan Li
Keyword(s):  
Northeast China ◽  
Urban Climate ◽  
Extreme Temperature ◽  
Maximum Temperature ◽  
Temperature Changes ◽  
Low Latitudes ◽  
Different Seasons ◽  
Extreme Minimum Temperature ◽  
Temperature Indices ◽  
Urbanization In China

Urbanization in China has been expanding dramatically since 1978, significantly affecting the extreme temperature changes in cities, which is a vital indicator of urban climate change. To assess urban-related effect on regional extreme-temperature changes in China, this study employed high-resolution land use data to divide meteorological stations into rural stations, suburban stations, and urban stations, and evaluated the annual and seasonal changes in extreme minimum temperature (TNN), mean temperature (Tavg) and extreme maximum temperature (TXX) at each meteorological station. The result revealed that extreme temperature indices (TNN, TXX) and Tavg increased significantly from 1960 to 2016 with varied degrees in different seasons and different regions. Extreme temperature indices in high latitudes increased more rapidly than in low latitudes; while the trends in summer are slower than in other seasons. Urbanization effects on the trends of TNN, Tavg and TXX were all statistically significant, but urbanization effects on TNN and Tavg were more significant than TXX. The urbanization effects were more significant in low altitudes, especially in North, South, Northwest and Northeast China. In North, Northwest and Northeast China, the urban-related effects on temperature increase were mainly observed in spring and winter, but in South China, the urban-related effects were more evident in summer. This study is valuable for sustainable urban planning in China.

Indices for daily temperature and precipitation based on quality controlled and homogenized data in Madagascar

2020 ◽  
Author(s):  
Luc Yannick Andréas Randriamarolaza ◽  
Enric Aguilar ◽  
Oleg Skrynyk
Keyword(s):  
Climate Change ◽  
Missing Data ◽  
Extreme Temperature ◽  
Maximum Temperature ◽  
Daily Minimum Temperature ◽  
Daily Maximum Temperature ◽  
Climate Indices ◽  
Low Density ◽  
Climate Data ◽  
Temperature And Precipitation

&lt;p&gt;Madagascar is an Island in Western Indian Ocean Region. It is mainly exposed to the easterly trade winds and has a rugged topography, which promote different local climates and biodiversity. Climate change inflicts a challenge on Madagascar socio-economic activities. However, Madagascar has low density station and sparse networks on observational weather stations to detect changes in climate. On average, one station covers more than 20 000 km&lt;sup&gt;2&lt;/sup&gt; and closer neighbor stations are less correlated. Previous studies have demonstrated the changes on Madagascar climate, but this paper contributes and enhances the approach to assess the quality control and homogeneity of Madagascar daily climate data before developing climate indices over 1950 &amp;#8211; 2018 on 28 synoptic stations. Daily climate data of minimum and maximum temperature and precipitation are exploited.&lt;/p&gt;&lt;p&gt;Firstly, the quality of daily climate data is controlled by INQC developed and maintained by Center for Climate Change (C3) of Rovira i Virgili University, Spain. It ascertains and improves error detections by using six flag categories. Most errors detected are due to digitalization and measurement.&lt;/p&gt;&lt;p&gt;Secondly, daily quality controlled data are homogenized by using CLIMATOL. It uses relative homogenization methods, chooses candidate reference series automatically and infills the missing data in the original data. It has ability to manage low density stations and low inter-station correlations and is tolerable for missing data. Monthly break points are detected by CLIMATOL and used to split daily climate data to be homogenized.&lt;/p&gt;&lt;p&gt;Finally, climate indices are calculated by using CLIMIND package which is developed by INDECIS&lt;sup&gt;*&lt;/sup&gt; project. Compared to previous works done, data period is updated to 10 years before and after and 15 new climate indices mostly related to extremes are computed. On temperature, significant increasing and decreasing decade trends of day-to-day and extreme temperature ranges are important in western and eastern areas respectively. On average decade trends of temperature extremes, significant increasing of daily minimum temperature is greater than daily maximum temperature. Many stations indicate significant decreasing in very cold nights than significant increasing in very warm days. Their trends are almost 1 day per decade over 1950 &amp;#8211; 2018. Warming is mainly felt during nighttime and daytime in Oriental and Occidental parts respectively. In contrast, central uplands are warming all the time but tropical nights do not appear yet. On rainfall, no major significant findings are found but intense precipitation might be possible at central uplands due to shortening of longest wet period and occurrence of heavy precipitation. However, no influence detected on total precipitation which is still decreasing over 1950 - 2018. Future works focus on merging of relative homogenization methodologies to ameliorate the results.&lt;/p&gt;&lt;p&gt;-------------------&lt;/p&gt;&lt;p&gt;*INDECIS is a part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant 690462).&lt;/p&gt;

scholarly journals A Study of Intraseasonal Temperature Variability in Southeastern South America

2012 ◽  
Vol 25 (17) ◽  
pp. 5892-5903 ◽  
Author(s):  
Gustavo Naumann ◽  
Walter M. Vargas
Keyword(s):  
Principal Component ◽  
Bimodal Distribution ◽  
Daily Basis ◽  
First Century ◽  
Maximum Temperature ◽  
Daily Maximum ◽  
South American ◽  
Regional Variability ◽  
Temperature Forecasting

Abstract The main goal of this work was to conduct an intraseasonal climate variability analysis using wavelet and principal component analysis over a southeastern South American daily maximum and minimum temperature series from the end of the nineteenth until the beginning of the twenty-first century. The analysis showed that there is a definite and coherent signal in the intraseasonal maximum and minimum temperatures. The most noticeable signal was observed during the winter months. The frequency of the intraseasonal signal was more complex for the maximum temperature, and in some stations, it displayed a bimodal distribution. A defined pattern that described a coherent variability between 30 and 60 days throughout the entire region was observed. This pattern potentially allows classification of the regional variability and adjustments to the temperature forecasting models on a daily basis.

scholarly journals Recent trends in daily temperature extremes over northeastern Spain (1960–2006)

2011 ◽  
Vol 11 (9) ◽  
pp. 2583-2603 ◽  
Author(s):  
A. El Kenawy ◽  
J. I. López-Moreno ◽  
S. M. Vicente-Serrano
Keyword(s):  
Land Use Planning ◽  
Crop Yields ◽  
Extreme Temperature ◽  
Daily Temperature ◽  
Maximum Temperature ◽  
Daily Maximum ◽  
Temperature Extremes ◽  
Growing Season Length ◽  
Cold Extremes

Abstract. Spatial and temporal characteristics of extreme temperature events in northeastern Spain have been investigated. The analysis is based on long-term, high-quality, and homogenous daily maximum and minimum temperature of 128 observatories spanning the period from 1960 to 2006. A total of 21 indices were used to assess changes in both the cold and hot tails of the daily temperature distributions. The presence of trends in temperature extremes was assessed by means of the Mann-Kendall test. However, the autocorrelation function (ACF) and a bootstrap methodology were used to account for the influence of serial correlation and cross-correlation on the trend assessment. In general, the observed changes are more prevalent in hot extremes than in cold extremes. This finding can largely be linked to the increase found in the mean maximum temperature during the last few decades. The results indicate a significant increase in the frequency and intensity of most of the hot temperature extremes. An increase in warm nights (TN90p: 3.3 days decade−1), warm days (TX90p: 2.7 days decade−1), tropical nights (TR20: 0.6 days decade−1) and the annual high maximum temperature (TXx: 0.27 °C decade−1) was detected in the 47-yr period. In contrast, most of the indices related to cold temperature extremes (e.g. cold days (TX10p), cold nights (TN10p), very cold days (TN1p), and frost days (FD0)) demonstrated a decreasing but statistically insignificant trend. Although there is no evidence of a long-term trend in cold extremes, significant interdecadal variations were noted. Almost no significant trends in temperature variability indices (e.g. diurnal temperature range (DTR) and growing season length (GSL)) are detected. Spatially, the coastal areas along the Mediterranean Sea and the Cantabrian Sea experienced stronger warming compared with mainland areas. Given that only few earlier studies analyzed observed changes in temperature extremes at fine spatial resolution across the Iberian Peninsula, the results of this work can improve our understanding of climatology of temperature extremes. Also, these findings can have different hydrological, ecological and agricultural implications (e.g. crop yields, energy consumption, land use planning and water resources management).

Qualification of Subsea Thermal Insulation for Extreme Temperatures

2004 ◽  
Author(s):  
Bjo̸rn Melve ◽  
Dana Ali ◽  
Jan-Christian Hu¨bert ◽  
Steinar Hommedal
Keyword(s):  
Thermal Insulation ◽  
Elevated Temperatures ◽  
Syntactic Foam ◽  
Extreme Temperature ◽  
Maximum Temperature ◽  
Accelerated Ageing ◽  
Critical Test ◽  
Insulation System ◽  
Hot Plate Test ◽  
Norwegian Sea

The Kristin field in the Norwegian Sea have a flowing wellhead temperature of 162 °C. This is believed to be the maximum temperature for an insulated subsea wellhead experienced to date. An extensive qualification program for the corrosion coating and thermal insulation was performed including accelerated ageing in water at elevated temperatures. The most critical test was the insulated hot plate test with holes down to the steel surface. For the extreme temperature of 162 °C a phenolic syntactic foam system showed the “least worse” results, and was chosen as the insulation system.

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