scholarly journals Spatial Distribution of, and Variations in, Cold Regions in China from 1961 to 2019

2022 ◽  
Vol 14 (1) ◽  
pp. 465
Author(s):  
Yumeng Wang ◽  
Jingyan Ma ◽  
Lijuan Zhang ◽  
Yutao Huang ◽  
Xihui Guo ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Spatial Interpolation ◽  
Global Scale ◽  
Rate Of Change ◽  
Spatial Change ◽  
Annual Average ◽  
Cold Regions ◽  
Average Temperature ◽  
Change Characteristics ◽  
Annual Average Temperature

In this study, on the basis of the temperature data collected at 612 meteorological stations in China from 1961 to 2019, cold regions were defined using three indicators: an average temperature of <−3.0 °C during the coldest month; less than five months with an average temperature of >10 °C; and an annual average temperature of ≤5 °C. Spatial interpolation, spatial superposition, a trend analysis, and a spatial similarity analysis were used to obtain the spatial distribution of the cold regions in China from 1961 to 2019. Then, the areas of the cold regions and the spatial change characteristics were analyzed. The results reveal that the average area of the cold regions in China from 1961 to 2019 was about 427.70 × 104 km2, accounting for about 44.5% of the total land area. The rate of change of the area of the cold regions from 1961 to 2019 was −14.272 × 104 km2/10 a, exhibiting a very significant decreasing trend. On the basis of the changes between 1991–2019 and 1961–1990, the area of China’s cold regions decreased by 49.32 × 104 km2. The findings of this study provide references for studying changes in the natural environment due to climate change, as well as for studying changes on a global scale.

scholarly journals Use of Historical Data to Assess Regional Climate Change

2019 ◽  
Vol 32 (14) ◽  
pp. 4299-4320 ◽  
Author(s):  
Yuchuan Lai ◽  
David A. Dzombak
Keyword(s):  
Climate Change ◽  
Time Series ◽  
The United States ◽  
Rate Of Change ◽  
Annual Average ◽  
Average Temperature ◽  
Historical Climate ◽  
Climate Records ◽  
Annual Average Temperature

Abstract Time series of historical annual average temperature, total precipitation, and extreme weather indices were constructed and analyzed for 103 (for temperature indices) and 115 (for precipitation indices) U.S. cities with climate records starting earlier than 1900. Mean rate of change and related 95% confidence bounds were calculated for each city using linear regression for the full periods of record. Box–Cox transformations of some time series of climate records were performed to address issues of non-normal distribution. Thirteen cities among the nine U.S. climate regions were selected and further evaluated with adequacy diagnoses and analyses for each month. The results show that many U.S. cities exhibit long-term historical increases in annual average temperature and precipitation, although there are spatial and temporal variations in the observed trends among the cities. Some cities in the Ohio Valley and Southeast regions exhibit decreasing or statistically nonsignificant increasing trends in temperatures. Many of the cities exhibiting statistically significant increases in precipitation are in the Northeast and Upper Midwest regions. The records for the cities are individually unique in both annual and monthly change, and cities within the same climate region sometimes exhibit substantially different changes. Within the full periods of record, discernible decade-long subtrends were observed for some cities; consequently, analysis of selected shorter periods can lead to inconclusive and biased results. These statistical analyses of constructed time series of city-specific long-term historical climate records provide detailed historical climate change information for cities across the United States.

scholarly journals The Spatial-temporal Variation of Precipitation and Temperature in Xinjiang in Recent 50 Years

2019 ◽  
Vol 1 ◽  
pp. 1-3
Author(s):  
Yuzhu Wang ◽  
Haowen Yan ◽  
Xiaoping Wang ◽  
Zhuo Wang
Keyword(s):  
Spatial Distribution ◽  
Temporal Variation ◽  
Annual Average ◽  
Northern Xinjiang ◽  
Average Temperature ◽  
Local Areas ◽  
Increasing Trend ◽  
Annual Average Temperature ◽  
Precipitation And Temperature ◽  
Southern Xinjiang

<p><strong>Abstract.</strong> Research purpose: To master the spatial-temporal evolution of precipitation and temperature in Xinjiang, and to provide reference for industrial, agricultural and transportation industries in the study area. Date and Rrsearch methods: Based on monthly precipitation and temperature data of 64 weather stations in Xinjiang in recent 50 years，the spatial-temporal variation of precipitation and temperature were analyzed by the methods of simple linear regression, 5-year moving average, radial basis function interpolation, sliding -t test, accumulated variance analysis, Mann-Kendall and morlet wavelet transform.</p><p>Research conclusion:</p><p>(1) The annual average precipitation (8.65&amp;thinsp;mm/10&amp;thinsp;a) in Xinjiang showed a significant increasing trend, and the increasing trend in local areas was:Northern Xinjiang (14.83&amp;thinsp;mm/10&amp;thinsp;a) &amp;gt; Southern Xinjiang(7.76&amp;thinsp;mm/10&amp;thinsp;a) &amp;gt; Eastern Xinjiang (3.37&amp;thinsp;mm/10&amp;thinsp;a).</p><p>(2) The spatial distribution of tendency rate of annual precipitation is basically the same as the spring, summer and autumn in Xinjiang, the tendency rate decreases from northwest to southeast, but the tendency rate of winter precipitation decreases from north to south.</p><p>(3) The precipitation of Xinjiang changed abruptly in 1989, Southern Xinjiang was relatively earlier (1986), Northern Xinjiang (1991) and Eastern Xinjiang (1990) were relatively delay.</p><p>(4) The main cycle of precipitation was 26&amp;ndash;30&amp;thinsp;a in Xinjiang and local areas, which predicts that the next 10 years will be a wet season.</p><p>(5) The annual average temperature (0.44&amp;thinsp;°C / 10&amp;thinsp;a) in Xinjiang is very significant, and the temperature increase trend in local areas is: Eastern Xinjiang (0.58&amp;thinsp;°C / 10&amp;thinsp;a) &amp;gt; Northern Xinjiang (0.45&amp;thinsp;°C / 10&amp;thinsp;a) &amp;gt; Southern Xinjiang (0.31&amp;thinsp;°C / 10&amp;thinsp;a).</p><p>(6) The spatial distribution of tendency rate of annual average temperature is basically the same as the four seasons in Xinjiang, and the tendency rate showed a decreasing trend from northeast to southwest.</p><p>(7) The temperature change of Xinjiang occurred in 1988,Northern Xinjiang was 1988 （relatively earlier), Southern Xinjiang and Eastern Xinjiang were 1992 (relatively delay).</p><p>(8) The main cycle of temperature in Xinjiang and local areas was 25&amp;ndash;30&amp;thinsp;a. It was predicted that the next 10 years would be high temperature period.</p>

Variations of Temperature in Hefei City in Recent 50 Years

2012 ◽  
Vol 616-618 ◽  
pp. 1496-1499
Author(s):  
Guo Wei Xu ◽  
Xin Tian Yuan ◽  
Shu Ling Huang ◽  
Yang Gao
Keyword(s):  
Statistical Analysis ◽  
Temperature Increase ◽  
Summer Temperature ◽  
Observation Data ◽  
Annual Average ◽  
Average Temperature ◽  
Four Seasons ◽  
Temperature Observation ◽  
Significant Temperature ◽  
Annual Average Temperature

Selecting 50 years temperature observation data from1959 to 2008 and using statistical analysis, this paper revealed the characteristics of temperature variation in Hefei city. The results show that in past 50 years, the annual average temperature in Hefei city greatly increased, tendency rate of temperature change was 0.246°C/10 a, especially after 1993, the temperature increased significantly; the temperature in four seasons all increased somewhat, warming was most prominent in spring. The most significant temperature increase was in spring, winter following behind, temperature increase in autumn was not obvious, and the average summer temperature increased the most unobvious.

scholarly journals Numerical simulation of formation and preservation of Ningwu ice cave, Shanxi, China

2015 ◽  
Vol 9 (2) ◽  
pp. 2367-2395 ◽  
Author(s):  
S. Yang ◽  
Y. Shi
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Process ◽  
Shanxi Province ◽  
Mechanism Of Formation ◽  
Annual Average ◽  
Average Temperature ◽  
Control Factors ◽  
Tourism Resource ◽  
Ice Water ◽  
Annual Average Temperature

Abstract. Ice caves exist in locations where annual average temperature in higher than 0 °C. An example is Ningwu ice cave, Shanxi Province, the largest ice cave in China. In order to quantitatively explain the mechanism of formation and preservation of the ice cave, we use Finite Element Method to simulate the heat transfer process at this ice cave. There are two major control factors. First, there is the seasonal asymmetric heat transfer. Heat is transferred into the ice cave from outside, very inefficiently by conduction in spring, summer and fall. In winter, thermal convection occurs that transfers heat very efficiently out of the ice cave, thus cooling it down. Secondly, ice–water phase change provides a heat barrier for heat transfer into the cave in summer. The calculation also helps to evaluate effects of global warming, tourists, etc. for sustainable development of ice cave as tourism resource. In some other ice caves in China, managers installed air-tight doors at these ice caves entrance intending to "protect" these caves, but this prevent cooling down these caves in winters and these cave ices will entirely melt within tens of years.

The Coincident Relationships between the Qehan Lake Area Fluctuation and the Climate Change in the Nearly 40 Years

2011 ◽  
Vol 137 ◽  
pp. 286-290 ◽  
Author(s):  
Xi Chun ◽  
Mei Jie Zhang ◽  
Mei Ping Liu
Keyword(s):  
Climate Change ◽  
Inner Mongolia ◽  
Climatic Factors ◽  
Annual Precipitation ◽  
Lake Area ◽  
Annual Average ◽  
Average Temperature ◽  
Changing Patterns ◽  
Annual Evaporation ◽  
Annual Average Temperature

The objective of this study is to analyse the climate changing patterns chronologically for exposing the coincident relationships between the lake area fluctuation and the climate change in Qehan lake of Abaga county of Inner Mongolia. The results show that there’s highly interrelation between the changes of the lake area and the climatic factors here, the annual average temperature and annual evaporation are negatively interrelate to the lake area fluctuation, and the annual precipitation interrelate to it is positive. The lake area has descended about 75 km2 during the nearly past 40 years. There were about two considerable lake expansions in 1973, 1998 through the generally lake area descending process.

scholarly journals Effects of solar activity and galactic cosmic ray cycles on the modulation of the annual average temperature at two sites in southern Brazil

2018 ◽  
Vol 36 (2) ◽  
pp. 555-564 ◽  
Author(s):  
Everton Frigo ◽  
Francesco Antonelli ◽  
Djeniffer S. S. da Silva ◽  
Pedro C. M. Lima ◽  
Igor I. G. Pacca ◽  
...  
Keyword(s):  
Solar Activity ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
Galactic Cosmic Rays ◽  
Southern Brazil ◽  
Solar Cycles ◽  
Annual Average ◽  
Average Temperature ◽  
Weather Stations ◽  
Annual Average Temperature

Abstract. Quasi-periodic variations in solar activity and galactic cosmic rays (GCRs) on decadal and bidecadal timescales have been suggested as a climate forcing mechanism for many regions on Earth. One of these regions is southern Brazil, where the lowest values during the last century were observed for the total geomagnetic field intensity at the Earth's surface. These low values are due to the passage of the center of the South Atlantic Magnetic Anomaly (SAMA), which crosses the Brazilian territory from east to west following a latitude of ∼ 26∘. In areas with low geomagnetic intensity, such as the SAMA, the incidence of GCRs is increased. Consequently, possible climatic effects related to the GCRs tend to be maximized in this region. In this work, we investigate the relationship between the ∼ 11-year and ∼ 22-year cycles that are related to solar activity and GCRs and the annual average temperature recorded between 1936 and 2014 at two weather stations, both located near a latitude of 26∘ S but at different longitudes. The first of these stations (Torres – TOR) is located in the coastal region, and the other (Iraí – IRA) is located in the interior, around 450 km from the Atlantic Ocean. Sunspot data and the solar modulation potential for cosmic rays were used as proxies for the solar activity and the GCRs, respectively. Our investigation of the influence of decadal and bidecadal cycles in temperature data was carried out using the wavelet transform coherence (WTC) spectrum. The results indicate that periodicities of 11 years may have continuously modulated the climate at TOR via a nonlinear mechanism, while at IRA, the effects of this 11-year modulation period were intermittent. Four temperature maxima, separated by around 20 years, were detected in the same years at both weather stations. These temperature maxima are almost coincident with the maxima of the odd solar cycles. Furthermore, these maxima occur after transitions from even to odd solar cycles, that is, after some years of intense GCR flux. The obtained results offer indirect mathematical evidence that solar activity and GCR variations contributed to climatic changes in southern Brazil during the last century. A comparison of the results obtained for the two weather stations indicates that the SAMA also contributes indirectly to these temperature variations. The contribution of other mechanisms also related to solar activity cannot be excluded. Keywords. Meteorology and atmospheric dynamics (climatology)

Feasibility Assessment for ORC Generation System Development Using Low Temperature Geothermal Water

2014 ◽  
Author(s):  
Seonghee Kho ◽  
Jayoung Ki ◽  
Myoungcheol Kang
Keyword(s):  
Hot Springs ◽  
System Development ◽  
Exceptional Case ◽  
Economic Feasibility ◽  
Geothermal Water ◽  
Operational Environment ◽  
Generation System ◽  
Annual Average ◽  
Average Temperature ◽  
Annual Average Temperature

Since around 70°C of geothermal water exists in Seokmo-do of Republic of Korea, this study is to assess the feasibility of electricity generation by utilizing ORC system, and the pertinent economic impact. It is generally believed that economic feasibility can be secured only when the source of geothermal water is above 100°C in order to generate electricity by operating ORC system. However, there was an exceptional case that ORC system was commercialized by Pratt-Whitney for around 70 °C of geothermal water in the hot springs of Chena, Alaska. The annual average temperature in the hot springs of Chena, Alaska is approximately 1°C whereas that of Seokmo-do is around 11°C, which makes 10°C of annual average temperature difference in operational environment between the two. Thus, the 2 phases of absorption refrigerating machine is considered for the ORC generation system. With establishing ORC system in consideration of operational environment, the feasibility of the development of ORC system in Seokmo-do is assessed by performance analysis and economic feasibility. As a result of the assessment, it is identified that the economic feasibility can be secured if the price of electricity is over $0.42/kWh same as that of photovoltaic generation as an incentive of the RPS program granted by the Korean government.

scholarly journals INFLUENCE OF TEMPERATURE AND ALTITUDE ON THE EXPANSION OF COFFEE CROPS IN MATAS DE MINAS, BRAZIL

2020 ◽  
Vol 28 ◽  
pp. 157-165
Author(s):  
Karine Rabelo Oliveira ◽  
Williams Pinto Marques Ferreira ◽  
Humberto Paiva Fonseca ◽  
Cecília Fátima Souza
Keyword(s):  
Area Under The Curve ◽  
Growth Potential ◽  
Maximum Temperature ◽  
Annual Average ◽  
Jackknife Test ◽  
Average Temperature ◽  
Annual Minimum Temperature ◽  
Precipitation Seasonality ◽  
Omission Rate ◽  
Annual Average Temperature

Coffee is among the most significant products in Brazil. Minas Gerais is the largest state producer of Arabica coffee. Coffee activity has excellent growth potential, which justifies the identification of new areas for expansion of the culture. This study aimed to determine factors that affect the spatial distribution of coffee plantations the most, as well as to identify areas with a greater aptitude for its expansion in the region of the Matas de Minas (63 municipalities). The MaxEnt software was used to elaborate a model capable of describing the area with the highest potential for estimating the probability of coffee adequacy. The elaboration of the model considered the records of occurrence, climatic and topographic variables of Matas de Minas, the second largest state producing region. The area under the curve (AUC), the omission rate and the Jackknife test were used for validation and analysis of the model. The model was accurate with an AUC of 0.816 and omission rate of 0.54% for the ‘test’. It was identified that the potential distribution of coffee in Matas de Minas is determined by changes in the annual maximum temperature, although it did not generate a significant gain when omitted, accounting for a considerable loss in the model. However, the most influential variables on the delineation of distribution were, the altitude and the annual average temperature. The most favorable areas for expansion of coffee culture in the Matas de Minas were found in the vicinity of the region of Alto Caparaó.Abbreviations used: A1 (altitude); A2 (maximum annual temperature); A3 (annual minimum temperature); BIO 1 (annual average temperature 1); BIO 4 (temperature seasonality), BIO 12 (annual precipitation); BIO 15 (precipitation seasonality); csv (comma-separated values); AUC (area under the curve).

scholarly journals Catálogo florístico del Macizo de Líbar (Parques Naturales Sierra de Grazalema y Los Alcornocales, Málaga-Cádiz, España).

2007 ◽  
Vol 32 ◽  
pp. 161-200 ◽  
Author(s):  
Manuel Becerra Parra ◽  
Estrella Robles Domínguez
Keyword(s):  
Red List ◽  
Nerium Oleander ◽  
Mountainous Area ◽  
Annual Average ◽  
Average Temperature ◽  
Natural Parks ◽  
Fraxinus Angustifolia ◽  
Annual Average Temperature ◽  
Quercus Rotundifolia ◽  
Península Ibérica

RESUMEN. Catálogo florístico del macizo de Líbar (Parques Naturales Sierra de Grazalema y losAlconocales, Málaga-Cádiz, España). El Macizo de Líbar es uno de los conjuntos montañosos másimportantes de la Serranía de Ronda y Andalucía Occidental. Su principal característica orográficaes la presencia de dos alineaciones montañosas que encierran una gran depresión intramontañosadenominada genéricamente los Llanos de Líbar. La vegetación dominante en los terrenos de naturalezacaliza la constituye el encinar, mientras que el alcornocal lo es de aquellas zonas donde afloran lasareniscas del Aljibe. A estas formaciones vegetales se suman otras como los quejigales, acebuchales,algarrobales, fresnedas, olmedas, adelfares y diversas formaciones de matorral. La climatología quedamarcada por ser una de las zonas con mayor precipitación de la Península Ibérica y por unastemperaturas bastante suaves durante todo el año, aunque en las zonas más altas la media anual seaproxima a los 10 ºC. Para llevar a cabo el estudio florístico del Macizo de Líbar se han realizadorecolecciones durante cinco años, en las que se ha pretendido herborizar la mayor parte del macizo,además de una revisión bibliográfica y consultas de los pliegos depositados en herbarios. El catálogoflorístico del Macizo de Líbar está formado por 826 taxones. De estos, 128 son endemismos, repartidosen endemismos ibéricos, ibero-mauritanos, bético, béticos-mauritanos, y rondeños. Son endemismosRondeños Linaria platycalyx, Reseda gayana subsp. undata, Saxifraga bourgeana, entre otros. Treceespecies están protegidas según la Ley de Flora y Fauna Silvestres de Andalucía y 32 taxones estánincluidos en la lista Roja de la Flora Vascular de Andalucía.Palabras claves. Flora, Catálogo, Macizo de Líbar, Sierra de Grazalema, Los Alcornocales, Málaga,Cádiz.ABSTRACT. Floristic catalogue of the Macizo of Libar (Natural Parks of Sierra de Grazalema andLos Alcornocales. Malaga-Cadiz, Spain). The Mountain of Líbar is one of the most important rangesof the mountainous area of Ronda and Western Andalusia. Its main orographic characteristic is thepresence of two mountainous alignments that delimit a great intramountainous depression denominatedLlanos de Líbar. The Quercus rotundifolia wood is the main vegetation in limestone lands, whereasthe Q. suber forest is dominant in sandstone zones. Other plants communities present in this area aredominated by Q. faginea, Olea europaea, Ceratonia siliqua, Fraxinus angustifolia, Ulmus minor,Nerium oleander and other shrublands. This is one of the zones with highest rainfall in the IberianPeninsula and with mild temperatures, although in the summits, the annual average temperature, decreases near 10 ºC. In order to carry out the botanical study, samplings have been made during fiveyears, in addition to a bibliographical revision and review of biodiversity databases. The botanicalcatalogue of Líbar is composed by 826 species, 128 are endemic species with different distributionarea. Linaria platycalyx, Reseda gayana subsp. undata or Saxifraga bourgeana are endemic from thearea of Ronda. 13 species are protected according to the Law of Wild Flora and Fauna of Andalusiaand 32 species are included in the plants Red List of Andalusia.Key words. Flora, Catalogue, Macizo de Líbar, Sierra de Grazalema, Los Alcornocales, Málaga,Cádiz.

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